A "lipo-protective" effect of a fixed combination of captopril and hydrochlorothiazide in antihypertensive therapy.

Increases of triglycerides and total cholesterol have been reported during treatment with antihypertensive drugs, most notably with beta blockers and diuretics. ACE inhibitors, on the other hand, are not known for having a negative effect on lipid profile. To evaluate the effects of a fixed combination of captopril and hydrochlorothiazide on lipid metabolism, blood pressure, and quality of life, we performed an open prospective study. A total of 2,154 patients with or without hypercholesterolemia, but not receiving lipid lowering drugs, were enrolled. Of the 1891 evaluable patients at baseline, 34.1% had a moderate risk with total cholesterol between 5.2 and 6.5 mmol/l (mean 5.8 mmol/l) and 41.3% had a high coronary heart disease (CHD) risk with total cholesterol higher than 6.5 mmol/l (mean 7.3 mmol/l). After six months of treatment, the median cholesterol level in the moderate risk group decreased from 5.8 to 5.4 mmol/l (p less than 0.0003) and in the high risk group from 7.3 to 6.3 mmol/l (p less than 0.0001). Triglycerides also decreased, whereas high density lipoprotein (HDL) increased in both risk groups. Systolic and diastolic blood pressure fell as expected and quality of life improved. The fixed combination was well tolerated. We observed a significant improvement of lipid profile in patients with mild to moderate hypertension while undergoing treatment with the fixed combination of captopril and hydrochlorothiazide. We suggest that captopril may balance the negative effects of hydrochlorothiazide on lipid metabolism in patients with hypertension and concomitant hyperlipidemia.


Noninvasive evaluation of left ventricular performance by the shortest distance between mitral leaflets coaptation and interventricular septum at end-systole.

We attempted to evaluate left ventricular performance from the shortest distance between the mitral leaflets coaptation and the interventricular septum at end-systole (MVC-IVS distance). The subjects were 37 patients with coronary artery disease (CAD) with prior myocardial infarction (MI), 8 with CAD without prior MI, 22 with atypical chest pain, and 4 with aortic regurgitation. The MVC-IVS distance was measured on a two-dimensional echocardiogram obtained from the parasternal or apical long-axis view and frozen at end-systole. Left ventricular end-systolic volume and end-diastolic volume were obtained by left ventriculography, and the left ventricular ejection fraction was calculated. A significant positive correlation was observed between the MVC-IVS distance and the end-systolic volume (r = 0.83, p less than 0.001); a close correlation was observed between the MVC-IVS distance end-systolic volume and ejection fraction by monoexponential fitting (r = -0.91, p less than 0.001). Thus, a significant negative correlation was observed between the MVC-IVS distance and the left ventricular ejection fraction (LVEF) (r = -0.83, p less than 0.001). An MVC-IVS distance of greater than or equal to 30 mm suggests diagnosis of left ventricular dysfunction (LVEF less than 50%) with high sensitivity (94.4%) and specificity (90.6%), while a value less than 30 mm suggests that the left ventricular performance is likely to be normal. Thus one can easily evaluate the left ventricular performance noninvasively using this new index.


Myocardial alterations induced by prolonged noradrenaline administration in various doses.

Prolonged noradrenaline administration to rats in steadily increasing dosages for a period of one to four weeks (cumulative doses 25-35 mg/kg) resulted in the development of focal necrotic areas with abundant collagen fibers and marked hypertrophy of cardiomyocytes. Cellular diameter was higher by 37-44% and extracellular space area by 70-100%. A combination of overcontracted and overdistended sarcomeres in some cardiomyocytes and a twofold rise in serum creatine kinase presumably reflected cellular calcium overload. Myocardial high energy phosphate content was depleted to 50-62% of the control level. The extent of this depletion positively correlated with a decrease in heart rate and cardiac output of the isolated heart. The latter may be attributed to limited left ventricular filling caused by elevated LV diastolic pressure and stiffness. Minimal metabolic and functional changes were observed after lowest noradrenaline dose (5 mg/kg for nine days) that was followed by only moderate depletion of myocardial phosphocreatine content and moderate rise in LV diastolic stiffness. Results suggest that energy-deficient increase in myofibrillar stiffness may form the basis for decreased myocardial distensibility and cardiac pump failure.


Electrophysiologic studies in atrial flutter.

The clinical electrophysiologic approaches to atrial flutter (F) have been activation mapping and the observation of changes induced by programmed stimulation. Sequential endocardial activation mapping has recently yielded information indicating that common F is produced by a large right atrial (RA) reentry circuit, with counterclockwise rotation in the frontal plane, including the inferior vena cava in its center. Functional block in the crista terminalis and conduction slowing in the approaches to the atrioventricular node seem to be important to support reentry. F inscribing positive deflections in the inferior leads usually follows the same path, but in a clockwise direction. Atypical F may be produced by left atrial circuits. Atrial stimulation during F entrains the circuit, resetting it with each stimulus. Collision between antidromic and orthodromic activation during entrainment produces fusion that can be identified in the surface electrocardiogram. The last paced activation restarts F, unless circuit penetration has been enough to modify it by block or disorganization. Entrainment may result in F acceleration, with changes in activation sequence, suggesting a different type of reentry, possibly based on functional factors.


Anatomy, histology, and pathology of coronary arteries: a review relevant to new interventional and imaging techniques--Part IV.

In the last 15 years, intense interest has focused on various interventional pharmacologic and mechanical forms of therapy for the treatment of atherosclerosis coronary artery disease. Many techniques and devices (dilating balloons, perfusion catheters, thermal probes and balloons, lasers, atherectomy devices, stents, intravascular ultrasound) have been used or are under study for future use. Many of these techniques and devices require an understanding of histologic and pathologic features of the coronary arteries and diseases which affect them. This article reviews selective areas of anatomy, histology, and pathology relevant to the use of various new interventional techniques. Part IV of this review will focus on congenital coronary artery anomalies, myocardial bridges, coronary aneurysm, emboli, and dissection and clinical implications regarding echocardiographic imaging techniques.


Triggered activity as arrhythmogenic mechanism after myocardial infarction: clinical and electrophysiologic study of one case.

In a woman with an old infarction and sustained ventricular tachycardia, tachycardias were only inducible after short-long RR sequences. After isoprenaline, tachycardias became incessant and all were preceded by short-long RR sequences. This strongly suggests that triggered activity plays a role in initiation of ventricular tachycardias in postinfarction patients.


His bundle ablation for supraventricular arrhythmias to avoid spurious shocks of an implanted defibrillator.

Atrial fibrillation with fast ventricular response remains a matter of concern in patients treated with an implantable cardioverter defibrillator (ICD). A patient with dilated cardiomyopathy, suffering from atrial arrhythmias and recurrent cardiac arrest due to both ventricular tachycardia and ventricular fibrillation, is presented. Ablation of the AV node by means of low-energy direct-current shocks with subsequent pacemaker implantation was performed before ICD implantation. The patient received shocks after four months, when he had recurrence of AV conduction with a slow ventricular rate. Pacemaker interaction was excluded, and no short ventricular arrhythmias were observed. During electrophysiologic study after electrical conversion of atrial fibrillation, persistent second degree heart block was documented, giving further evidence that atrial arrhythmias were not responsible for the shocks. The patient's functional status remains good after more than 18 months of follow-up.


Splenic infarction: a complication of cardiac catheterization.

Patients with extensive atherosclerosis are at increased risk of developing embolic complications during cardiac catheterization. We describe a 51-year-old man with unstable angina and bilateral leg claudication who developed fever and right upper abdominal pain shortly after cardiac catheterization. Liver-spleen scintigraphy demonstrated a wedge-shaped filling defect compatible with splenic infarction, and serial scans performed over a period of five months showed resolution of this finding. Splenic infarction tends to be under-diagnosed, and physicians should be aware of this potentially serious complication of cardiac catheterization.


A case of accessory mitral valve leaflet associated with solitary mitral cleft.

Accessory mitral valve leaflet is a rare congenital anomaly. More than half of the cases show other congenital cardiac defects and almost all of the cases show subaortic obstruction. We report a case of an accessory mitral valve tissue without outflow obstruction associated with mitral cleft of the posterior mitral leaflet. To our knowledge, this is the first reported case of the combination of these two congenital anomalies.


Clinical significance and management of arrhythmias in the heart failure patient.

Congestive heart failure (CHF) is a common manifestation of hypertension, coronary artery disease, and dilated cardiomyopathy. The Framingham study showed that the incidence of CHF increases twofold with each decade of age. The presence of CHF increases the age-adjusted death rate 5.5-fold for women and 8-fold for men, and it increases the sudden death rate 5.5-fold in both men and women. Ventricular arrhythmias are a common accompaniment of CHF. Ambient ventricular premature complexes occur in most of these patients, and nearly one half of all CHF patients will have nonsustained ventricular tachycardia on a 24-h ambulatory electrocardiographic (Holter) recording. In addition, low left ventricular ejection fraction (LVEF) predicts inducible sustained ventricular tachycardia on electrophysiologic study. One-year mortality increases with worsening New York Heart Association (NYHA) Functional Class and decreasing LVEF. As the overall yearly mortality increases, the proportion of patients who die of arrhythmias decreases. The precise mechanism of death is frequently difficult to assess. Nonarrhythmic causes of death include CHF, shock, electromechanical dissociation, and myocardial rupture. Arrhythmic causes are most commonly due to ventricular tachycardia/ventricular fibrillation. Bradycardic events (asystole or heart block) are usually associated with progressively worsening CHF. Noncardiac causes that may confuse classification include pulmonary embolus and cerebrovascular accident. Because many patients have ischemic heart disease as the etiology of the CHF, a recurrent ischemic event can likewise make classification difficult. Overall, approximately one half of all deaths in CHF are arrhythmic and one half are nonarrhythmic.


Congestive heart failure: new therapeutic strategies.

Angiotensin converting enzyme inhibitors (ACE-I) are widely used in patients with severe heart failure on the basis of the significant improvement in mortality in the CONSENSUS-I trial in patients with Class IV heart failure. Recent data from the 5-year clinical trial Studies of Left Ventricular Dysfunction (SOLVD) suggest a role for ACE-I in patients with mild to moderate heart failure as well as in those with asymptomatic left ventricular dysfunction. The SOLVD treatment trial in patients with a left ventricular ejection fraction (LVEF) less than or equal to 35% and treated for heart failure with conventional therapy including digitalis, diuretics, or vasodilators demonstrated that the addition of enalapril resulted in a significant reduction in mortality from heart failure as well as in the combined end point of death plus hospitalization from heart failure. These data suggest that ACE-I should be the base of therapy for patients with mild to moderate heart failure, as well as for those with severe heart failure.


Management of heart failure in valve regurgitation.

Heart failure from valve regurgitation usually results from aortic and/or mitral valve dysfunction. Heart failure resulting from acute and chronic valve regurgitation should be considered separately.


Management of the patient awaiting cardiac transplantation.

The spectacular clinical success of heart transplantation (HTTX) in the cyclosporine era has engendered challenging new clinical problems that include long-term management of patients with severely compromised systolic function, preparation of potential HTTX recipients for major surgery followed by immunosuppression, and ethical and rational distribution of limited numbers of donated organs. The magnitude of these challenges may seem overwhelming. Fortunately, clinicians have the luxury of dealing with the issues involved one patient, and one step, at a time. The continued efforts of clinical investigators have clarified important management principles. There is a growing appreciation of the pivotal importance of mitral valve function in determining the response to medical therapy and long-term prognosis in this patient population. Enthusiasm for pharmacologic control of asymptomatic ventricular ectopy has waned; instead, the restoration and maintenance of normal atrial function has clearly taken precedence. In preparation for surgery, new endoscopic techniques offer great advantages. The use of high-technology support devices as "bridges to transplantation" has been re-examined in view of the relatively poorer short- and long-term prognosis of patients managed with these devices. Increasingly, the optimal scenario for HTTX entails transplantation of a severely compromised but medically stable patient. As specific therapy, HTTX today has relatively limited application to the vast majority of patients with heart failure (HF). Seventeen hundred heart transplants will do little to directly affect the 400,000 patients in the United States who each year develop symptomatic HF.(ABSTRACT TRUNCATED AT 250 WORDS)


Strategies to manage the heart failure patient after transplantation.

Cardiac transplantation has emerged as an effective form of therapy for end-stage congestive heart failure (CHF), but patients are predisposed to both dilated and restrictive congestive physiology. The etiologies of post-transplant CHF are unique and complicated, most certainly reflecting a chronic rejection process that has yet to be elucidated. Successful identification of underlying pathophysiologic mechanisms and subsequent therapeutic approaches will require close coordination among cardiologists, cardiac surgeons, and immunobiologists.


Pathophysiology of congestive heart failure.

Congestive heart failure is a syndrome common in the United States, especially in elderly patients. The most common etiology is coronary artery disease. A number of general factors contribute to the heart failure syndrome, including loss of muscle, decreased myocardial contractility, pressure or volume overload, or restricted filling. All of these factors may play a role in a given patient as, for example, with coronary artery disease. Although systolic dysfunction with a reduced ejection fraction is the most common heart failure syndrome, up to 40% of patients may have a relatively preserved ejection fraction with diastolic dysfunction. As the heart begins to fail, a number of compensatory mechanisms are activated. These include increased heart rate, the Frank-Starling mechanism, increased catecholamines, activation of the renin-angiotensin system, and release of atrial natriuretic peptides. Although these mechanisms are initially helpful to the cardiovascular system, they frequently overshoot, initiating a vicious cycle. For example, with a decrease in cardiac output, there is a reflex increase in systemic vascular resistance in order to maintain perfusion pressure. This increase in resistance, however, acts as a load on the left ventricle and further reduces cardiac output. The best evidence for the existence of this vicious cycle is the beneficial change in hemodynamics produced by vasodilator drugs and the ACE inhibitors. Thus, an understanding of pathophysiology allows for the selection of rational therapy. An unresolved problem in heart failure patients is how best to reduce the high incidence of sudden death, which is one of the major challenges for the future.


Tiopronine-induced reduction of rheumatoid factor functional affinity and asialylated IgG in patients with rheumatoid arthritis.

Serum and synovial fluid (SF) from 16 rheumatoid arthritis patients were evaluated before and after a 2-month treatment with tiopronine (TP). The levels of rheumatoid factor (RF) declined, as did the functional affinity of the remaining RF (p less than 0.01 in serum and p less than 0.05 in SF). Concomitant restoration of the sialylation of IgG was observed (p less than 0.05 in serum and SF). Following an initial increase, a significant reduction was observed in the level of soluble interleukin-2 receptors in serum (p less than 0.05) and SF (p less than 0.05) after treatment with TP.


Sjögren's syndrome and mixed connective tissue disease.

We investigated the clinical significance of the close association of Sjögren's syndrome (SS) with mixed connective tissue disease (MCTD) by analyzing the clinical manifestations, sialographic findings and immunological parameters of MCTD and primary SS. The prevalence of sialectasia or SS in MCTD was significantly higher than in any other connective tissue diseases. The prevalence of Raynaud's phenomenon, swollen fingers, arthralgias, lymphadenopathy, sclerodactyly, muscle weakness, fever and erythema was significantly higher in MCTD than in primary SS. There were no significant differences between these manifestations in MCTD patients with sialectasia or SS, and those in MCTD patients without sialectasia or SS. Although the levels or prevalence of the erythrocyte sedimentation rate, CRP, antinuclear factor, anti-DNA antibody and anti-RNP antibody were significantly greater in MCTD than in primary SS, there were no significant differences in the levels or the prevalence of laboratory abnormalities between MCTD with sialectasia or SS, and MCTD without sialectasia or SS. Moreover, there was a strict dissociation between the occurrence of anti-RNP antibody and anti-SS-B antibody both in MCTD and primary SS. These results suggest that the association of secondary SS or sialectasia in MCTD, although more common than in other connective tissue diseases, is merely a consequence of MCTD and does not influence the clinical course of MCTD.


The effects of 20 weeks of physical fitness training in female patients with fibromyalgia.

During a period of 20 weeks 18 female patients with fibromyalgia participated in a 60-minute exercise program twice a week. A control group, comprising 17 patients, was told not to change their physical activity level. Eleven patients in the training group and fourteen in the control group completed the study. The results at entry were compared to those after 20 weeks, as well as being compared to the results of the control group. No statistically significant changes or differences in general pain, pain coping and fatigue were seen after 20 weeks. Improved dynamic endurance work performance for the upper extremity was found, however, in the training group, measured as the strength of the first (p = 0.01) and the last repetition (p = 0.003). These results differed from the results of the control group (p = 0.02 and p = 0.003). It is concluded that fibromyalgia patients may undergo low-intensity dynamic endurance training without experiencing exacerbation of their general pain and fatigue symptoms.


Salivary gland echography in primary and secondary Sjögren's syndrome.

A series of different ultrasonographic abnormalities detected by salivary gland echography (SGE) were investigated for their discriminant power for Sjögren's syndrome (SS) in 53 patients with either primary SS (n = 27) or secondary SS (n = 26), as well as in 90 controls. Among the controls, 26 suffered from dry mouth and/or recurrent or persistent swelling of at least one parotid or submandibular gland due to other selected disorders, while 64 were healthy, asymptomatic subjects. Mild, evident or gross inhomogeneous parenchymal patterns were the only variables selected by stepwise discriminant analysis, when comparing patients to controls. However, a mild submandibular inhomogeneity did not prove useful for such a discrimination. Based on these data, a simplified evaluation and standardised quantification of salivary involvement, as detected by SGE, is proposed using an echographic score (range 0 to 6) which assigns points to the different degrees of glandular inhomogeneity. Score values above 0 showed a sensitivity of 88.8% in primary SS and of 53.8% in secondary SS, as well as a specificity of 84.6% and of 92.2% with respect to either symptomatic or healthy controls. The lower sensitivity of SGE for patients with secondary SS presumably was a result of their milder salivary involvement.


Reflex sympathetic dystrophy syndrome: a review.

Reflex sympathetic dystrophy syndrome is a serious and potentially disabling condition. Early diagnosis and treatment are essential to control the disorder and restore the patient's quality of life. The cardinal clinical features, radiological changes, etiopathologic advances, and current approaches to proper diagnosis and treatment will be discussed.


Successful treatment of psychosis secondary to SLE with high dose intravenous immunoglobulin.

A 23-year-old woman with SLE was admitted because of severe psychosis manifested by depression, delusions and the inability to perform minimal daily activities. The patient refused treatment with steroids, but was later convinced to try treatment with intravenous immunoglobulin (IVIG). Following treatment with IVIG a marked improvement was noted in her mental status and she was discharged. During a follow-up period of 18 months she resumed normal life; she does not receive any drugs currently and no psychiatric abnormalities have been noted. It is suggested that IVIG may be considered in the treatment of lupus cerebritis, especially when serious complications develop and other treatment modalities are ineffective.


Spondyloepiphyseal dysplasia tarda simulating juvenile arthritis: clinical and molecular genetic observations.

A sibship is reported in which two of three children developed a symmetrical polyarthropathy associated with a mild spondyloepiphyseal dysplasia. Although the physical findings resembled juvenile arthritis, laboratory investigations for inflammatory disease were entirely negative. Molecular studies in members of this family showed that none of them had any structural rearrangements or other major abnormality of the type II procollagen gene (COL2A1). The laboratory findings in this family with "pseudo-rheumatoid arthritis" do not exclude the possibility of a minor mutation of the type II procollagen gene or a defect in the processing of articular cartilage collagens.


Synovial extracellular matrix II. Specific incorporation of immunoglobulin into the cell-free matrix of pannus.

To determine whether immune complex-like material is incorporated into the extracellular matrix (ECM) of proliferated RA synovium, cell-free matrices were isolated from pannus removed at joint replacement surgery, and were subjected to differential extraction. When the IgG and albumin concentrations in the ECM extracts were compared to those in simultaneously obtained synovial fluids, the IgG was found to be enriched 8.8-fold. Approximately 95% of the IgG was extractable with 6M Guanidine-HCl and 8 M Urea-B-ME. Further extraction with collagenase and low-pH buffers did not result in any additional recovery of IgG. Matrix-associated IgG demonstrated a restricted mobility on IEF with a pI of 4.8. The extracellular matrix of RA pannus is enriched in an acidic IgG species. Incorporation of IgG appears to be secondary to non-covalent interactions and may represent an additional reservoir of immune complex material in the rheumatoid joint.


Scintimetric study of the bone response around noncemented knee prosthesis. Preliminary results.

The bone response to a noncemented knee prosthesis was observed by quantified isotopic gammagraphy. One hundred six sequential scintimetric explorations were performed in 36 patients with total knee arthroplasty. Fifteen areas of interest were taken into consideration and their gammagraphic analyses were compared with radiologic findings during a postsurgery period of 24 months. Starting with a very high radionuclide uptake level obtained in the first postsurgery level, a gradual decrease was correlated with osteoblastic activity. In this first evaluation, the gammagraphic response around the implant is different in biologic prostheses than in cemented ones. These data may be useful for evaluating implants in orthopedic surgery.


Molecular detection of persistent Borrelia burgdorferi in a man with dermatomyositis.

A 40-year-old white man with a several year history of various immunologic disorders, including anti-Jo-1 autoantibody positive dermatomyositis, developed clinical Lyme disease after being biten by a tick. The patient was treated with oral tetracycline and his initial symptoms resolved; however, he suffered an exacerbation of his muscle disease which was difficult to control despite cytotoxic therapy. Antibiotic therapy was reinstituted after Borrelia burgdorferi was detected in the patient's peripheral blood leukocytes by the polymerase chain reaction (PCR). All serologic, T-cell stimulation, and western blot analyses, however, were negative. The patient's disease responded to oral ampicillin, probenecid therapy and concurrent cytotoxic therapy. Subsequent leukocyte PCR testing has been negative for the causative agent of Lyme disease. This case may provide an example of the in vivo immuno-modulatory effects of spirochetes in human autoimmune disease. In addition, this case emphasizes the potential clinical utility of PCR technology in evaluating the persistent sero-negative Lyme disease which may occur in immunocompromised individuals.


Intact articular cartilage cryopreservation. In vivo evaluation.

By varying the parameters that determine the cryopreservation process (freezing rate, storage temperature, cryoprotective agents, storage time), various protocols have been designed for preservation of osteochondral allografts of rabbit femoral condyles. The grafts were implanted orthotopically for three months. After harvesting, the results were evaluated by optical microscopy, histochemistry, and electron microscopy (scanning and transmission). A quantitative study and statistical analysis was performed using a gradation scale of chondral degeneration. Synovial reaction was higher in the fresh allograft than in the cryopreservation groups. Glycerol yielded better results than DMSO as a cryoprotective agent. No cryopreservation protocols produced the results equal to the control groups of either fresh auto- or allografts. Optimal preservation was achieved with either the group with hypothermic storage at 4 degrees for no more than 48 hours or the group with slow freezing to -80 degrees and preparative exposure to 15% glycerol at 4 degrees for 60 minutes. No statistically significant differences were found in these two groups.


Ilizarov technique. Results and difficulties.

Of 100 cases treated by the Ilizarov method, 91 patients were reviewed from February 1985 to March 1990. There were 32 tibial fractures (29 open) and 21 nonunions (nine infected). There were 47 cases of limb lengthening (28 tibia and 19 femur). The results were as follows: good, 83%; fair, 13%; and poor, 4%. Slight and intermittent pain in some wire of the device was frequent (69%). Average bone healing time in tibial fractures was 4.95 months and 5.83 months in tibial nonunions. In bone-lengthening operations, the average lengthening index in the tibia was 1.02 months/cm (lengthenings ranged from 3 cm to 10 cm, with a mean of 5.71 cm), whereas in the femur, the average lengthening index was 1.14 months/cm (lengthenings ranged from 3 cm to 7 cm, with a mean of 5.34 cm). Manually-tensed wires produced frequent problems (24.5%), whereas wire tensed by the dynamometric tensioner produced problems in only 7.8% of the cases. Despite good results, the Ilizarov technique requires adequate training to reduce an overall complication rate (approximately 30%).


The value of preemployment roentgenographs for predicting acute back injury claims and chronic back pain disability.

Preemployment roentgenographs have long been used in industry to screen job applicants. Roentgenographs have had little effect, however, in curbing the cost of back problems in industry. This study evaluates the capabilities of preemployment roentgenographs for predicting acute back injury claims within the longshoring industry and for predicting back problems that lead to back disability of more than six months. The data indicate that lumbosacral roentgenographs are not helpful in predicting who is more likely to make a back injury claim, or those few who make up the vast majority of the costs for industrial back pain by becoming disabled for more than six months. Lumbosacral roentgenographs have little link to back disorders and may be viewed as discriminatory. The radiation exposure is not justified by their predictive value as a preemployment screening tool.


Does the combined ventral derotation system (VDS) followed by Harrington instrumentation improve the vital capacity in patients with idiopathic double major curve pattern scoliosis? An analysis of 33 cases and review of the literature.

A young, homogenous population of 33 patients with idiopathic scoliosis of double major curve pattern (DMC), a mean thoracic curve of 70.6 degrees (standard deviation [SD] = 20.6), and a mean lumbar curve of 72.9 degrees (SD = 15), had a measurement of the vital capacity (VC) at rest before and at a minimum of one year after combined ventral derotation system (VDS). This was followed by Harrington instrumentation and fusion to evaluate the effect of scoliosis, kyphosis, and their surgical correction on VC at rest. A regression analysis showed that the VC was significantly lowered before operation to 69.6% of predicted value, whereas individuals with thoracic curvatures greater than 70 degrees had a lower VC. The surgical correction of the thoracic curve of 50.8% and the lumbar curve of 68.4% was permanent in the follow-up evaluation, and the functional improvement in postoperative VC was 4.36%, statistically not very significant. The time between the two evaluations did have a significant statistical correlation with the observed improvement of the VC. The longer the interval between the two evaluations, the better the improvement of the VC. The age of the patient at the time of the first (VDS) operation influences the changes of the observed VC, significantly favoring the younger patients. The number of the functional vertebral segments included by the spinal instrumentation and fusion does not improve the VC.(ABSTRACT TRUNCATED AT 250 WORDS)


Fracture of the body, neck, or spine of the scapula. A long-term follow-up study.

Fractures of the scapula are often considered benign lesions with a favorable outcome. The aim of the current study was to analyze the long-term results after fracture of the muscle-covered parts of the scapula: its body, neck, and spine. Sixty-eight patients were available for clinical examination 14 years after they had sustained a fracture of the scapula. The fractures had been treated with immobilization and early active motion. The follow-up rating was based on patient satisfaction and shoulder motion. Fifty-one patients were rated good, 15 were rated fair, and two were rated poor. Forty-eight shoulders were roentgenographically reexamined. Fourteen had a moderate and six had a pronounced deformity of the scapula. Scapula deformity was associated with pain in eight of the shoulders. The results of the current study suggest that the long-term course after fracture of the scapula is not uniformly favorable. Fifty percent of the patients with residual scapula deformity have shoulder symptoms. In most cases, however, the shoulder disablement is slight or moderate.


Glenoid dysplasia. A case report and review of the literature.

Glenoid dysplasia is a rare congenital abnormality that may be associated with vague shoulder pain, limitation of motion, and weakness of the upper extremity. In many cases it is an incidental finding on chest roentgenogram, and high-level function is usually possible before the onset of symptoms or degenerative changes. The case of an 18-year-old collegiate football offensive lineman who developed symptoms secondary to previously undetected bilateral glenoid dysplasia is reported. Roentgenograms demonstrated dysplastic scapular necks, and arthrography showed a deformed, constricted shoulder capsule. Magnetic resonance imaging defined the extent of the cartilaginous anlage, and arthroscopy demonstrated progressive articular cartilage degeneration. Although treatment alleviated the shoulder symptoms at low-level activities, the patient was unable to successfully compete under the extreme demands of an American football lineman.


Acetabular roof reinforcement rings.

A series of 30 total hip arthroplasties was performed in 29 patients with the use of the Mueller roof reinforcement ring (RRR). The mean follow-up observation time was 30 months (standard deviation [SD] = 7.6). The clinical and radiologic results were evaluated according to the Mayo Clinic scoring system. The overall preoperative clinical score of 21.963 (SD = 18.776) points improved to a follow-up examination score of 69.533 (SD = 11.599), a correction of 68.41%. The authors' goal in this series was to implant the ring together with the polyethylene socket as close to the anatomic position of the acetabulum as possible. There was no loosening of the RRR or the polyethylene sockets, nor was there material failure in the last evaluation of the hips. No statistically significant difference was found when the differences between the follow-up scores of the primary versus the revisionary procedures were compared. The roof replacement ring has been helpful for primary and revision arthroplasties of acetabular deficiencies occurring within five years after operation.


Long-term results of total arthroplasty in adolescents with debilitating polyarthropathy.

The authors retrospectively reviewed 29 hip and 13 knee arthroplasties performed in 17 adolescents and young adults from 1973 through 1979. Most patients had severe multiple joint involvement; 16 had juvenile rheumatoid arthritis. Clinical and roentgenographic evaluations were performed before operation and at routine intervals for up to 11 years after operation. The average final follow-up evaluation was at ten years seven months. The modified Harris rating improved from 17 before operation to 68 at final evaluation. A dramatic improvement was noted in the ambulatory ability of 13 patients in whom increased joint motion and reduced deformity was observed at follow-up evaluation. At the 11-year roentgenographic review, 32% of hips had gross loosening, and an additional 39% had radiolucent lines greater than 2 mm in thickness in more than two radiographic zones. No lucency greater than 2 mm was noted in any of the knee replacements. Complications included one immediate collapse of the medial tibial plateau, four femoral fractures, one hip dislocation, and one case of arthrofibrosis. Despite untoward roentgenographic results and the high incidence of complications, total arthroplasty has dramatically improved the quality of life for these patients with multiple joint pathology. For this reason, the authors continue to recommend joint replacement in these individuals and the use of new prosthetic designs and surgical techniques.


Tissue growth into porous-coated acetabular components in 42 patients. Effects of adjunct fixation.

Histologic examination was performed on 42 uncemented, porous-coated acetabular components removed for reasons not related to fixation. Included were 20 devices that had fixed pegs or spikes to aid in initial fixation and 22 devices that used screws through the component. The diagnoses and patient ages at insertion, times in situ, and reasons for removal were comparable for the two groups. Bone ingrowth was observed in 28 of the 42 acetabular components (67%). Of the 20 components with pegs or spikes, nine had no bone ingrowth, six had minimal bone ingrowth, four had moderate ingrowth, and one had extensive bone ingrowth. Of the 22 components with screws, five had no bone ingrowth, six had minimal bone ingrowth, six had moderate bone ingrowth, and five had extensive bone ingrowth. Two of the devices with screws also had external threads on the metallic shell; neither had any bone ingrowth, and the two accounted for two of the five devices having no bone ingrowth in this group. Bone ingrowth occurred more frequently, in greater amounts and was more evenly distributed anatomically in cups using screws for initial adjunct fixation. Roentgenographic and clinical findings were unreliable in predicting ingrowth of bone.


Efficacy of alumina ceramic heads for cemented total hip arthroplasty.

Fifty-seven cemented total hip arthroplasties (THAs) were reviewed in cases of osteoarthrosis secondary to congenital dysplasia or dislocation. The bearing surface of the prosthesis used in this series consists of a polyethylene acetabular component on an alumina ceramic head. All acetabular components were positioned at the same level as the original acetabulum, and an autologous femoral head graft was performed for 18 hips. The follow-up period ranged from five to eight years, averaging six years two months. The latest survey showed excellent and good results for 53 hips (92.9%). Four acetabular components (7%) and two femoral components (3.5%) showed roentgenographic evidence of loosening. Only one hip (1.8%) had to be treated with revision surgery for femoral component loosening. None of the cases suffered a broken ceramic head. The use of a total hip prosthesis with an alumina ceramic head in THA is likely to lead to excellent results for patients with osteoarthrosis of the hip.


Osteon morphometry in females with femoral neck fractures.

The authors measured osteon dimensions and number in specimens of cortical bone obtained from the medial femoral neck (calcar) from nine female patients treated with hemiarthroplasty for femoral neck fractures, and from 12 (seven women, five men) age-matched cadavers without fractures. Specimens from the same location in 14 (seven women, seven men) younger patients treated with total hip arthroplasty (THA) for osteoarthrosis were also studied. There were fewer osteons per unit area and the osteons and their Haversian canals were bigger in the fracture group than in the nonfracture or osteoarthritic groups. Patients with femoral neck fractures also exhibited a decreased Singh index and an increased intracortical porosity compared with age-matched normal controls. By contrast, the osteoarthritic group showed no difference in osteon or Haversian dimensions, osteon number per unit area, Singh index, or in porosity compared with the nonfracture group. These morphometric differences found in the cortical bone of the medial femoral neck may play a role in the incidence of fractures.


Tibial tunnel placement in anterior cruciate ligament reconstructions and graft impingement.

Fifty-six anterior cruciate ligament (ACL) reconstructions had a magnetic resonance scan of the ACL graft six months after operation. The impingement-free grafts (n = 26) had a low magnetic resonance signal from origin to insertion. Impinged grafts (n = 30) had an increased magnetic resonance signal confined to the distal two thirds of the graft. The location of the tibial tunnel (TT) was determined from a lateral roentgenogram. Positioning the center of the TT 12-23 mm from the anterior edge of the tibia consistently produced graft impingement and flexion contractures. Roof impingement was avoided and hyperextension was regained when the TT was centered more posteriorly within a 6-mm impingement-free zone (22-28 mm from the anterior edge of the tibia). Stability and knee extension were significantly better when the center of the TT was 2-3 mm posterior to the center of the normal ACL insertion.


Open and arthroscopic synovectomy in hemophilic arthropathy of the knee.

Open and arthroscopic synovectomies of the knee in patients with classic hemophilia were evaluated with regard to effectiveness in reducing bleeding episodes, the effect on range of motion (ROM), and roentgenographic progression of hemophilic arthropathy. Eleven patients underwent 13 synovectomies (eight open, five arthroscopic). The average follow-up periods were 7.9 years and 2.2 years for the open and arthroscopic groups, respectively. Both procedures significantly reduced recurrent hemarthroses. Knee ROM in the open synovectomy group was decreased or unchanged in 75% and minimally increased in 25%, whereas there was an increased in 80% and a decrease in 20% of the knees in the arthroscopic group. Furthermore, 62.5% of the knees required manipulation to improve ROM in the open synovectomy group, versus 0% in the arthroscopic group. Hemophilic arthropathy progressed in most knees in both groups. The arthroscopic group had a longer operative procedure (122 versus 59 minutes), but required less hospitalization (9.4 versus 23.1 days) and 25.6% less Factor VIII replacement. Both techniques reduce hemarthroses. There is usually a net loss of ROM with the open versus a net gain with the arthroscopic procedure, and roentgenographic progression hemophilic arthropathy is slowed but not halted after synovectomy.


The snapping biceps femoris syndrome.

Snapping of tendons is a well-described entity in the literature, occurring mostly in athletes around the hip, ankle, shoulder, and elbow, but rarely the knee. A case of snapping of the biceps femoris tendon (BFT) in a patient with a painful knee and no history of trauma is described. An abnormal anterior insertion of the BFT was found to be the cause of the pain and snapping. Surgical treatment, reinsertion of the tendon in its anatomic position, completely corrected the abnormality, whereas conservative treatment failed.


The long-term course of various meniscal treatments in anterior cruciate ligament deficient knees.

One hundred thirty-five patients were reviewed six to 16 years after anterior cruciate ligament repair or reconstruction. At follow-up evaluation, 60% of the patients demonstrated significant residual laxity on objective testing. Thirty percent of the patients reduced activity levels because of instability. Degenerative arthritis was noted to be more frequent in those patients who had been treated with total open meniscectomy than in those treated with arthroscopic partial meniscectomy, and it was more severe than in patients with intact menisci. Continued participation in high-stress sporting activities generally led to a high rate of further injuries, reoperations, and progression of osteoarthrosis.


Semitendinosus Kennedy ligament augmentation device anterior cruciate ligament reconstruction.

This is a prospective study of 78 chronic unilateral isolated anterior cruciate ligament (ACL) patients who were treated with an arthroscopically-assisted reconstruction technique using the semitendinosus tendon, occasionally associated with the gracilis, augmented with the Kennedy-ligament augmentation device (LAD). There was a minimum two-year follow-up period (mean, 34.3 months; range, 24-50 months). Ligamentous surgery was always restricted to the ACL intraarticular reconstruction. Preoperative, intraoperative, and postoperative examinations at three, six, 12, 18, and 24 months, and every year thereafter, including subjective and objective evaluation with KT 1000 arthrometer laxity measurements, were completed. Two-year examination data were available on 77 (98.7%) of the 78 patients compared with preoperative data. The pivot shift (side-to-side difference) improved from 49.3% with Grade 0-1 to 92.2% with Grade 0-1. KT 1000 20-pound anterior drawer (greater than 5 mm side-to-side difference) improved from 49.3% (mean, 6 mm) to 91.1% (mean, 0.55 mm). KT 1000 maximum manual anterior drawer (greater than 5 mm side-to-side difference) improved from 21.9% (mean, 7.8 mm) to 97.4% (mean, 0.55 mm). After ACL reconstruction, 89.6% of patients had a full range of motion and only 10.3% had flexion contractures of less than 5 degrees; 5.2% of patients had mild effusion. Functional Lysholm knee scoring of 100 points improved from 7.7% scoring over 85 points preoperatively (mean, 66.5) to 92.1% postoperatively (mean, 95.6). Instability was controlled in 89.4% of the patients, and 71.4% have been involved in sports after injury. Anterior cruciate ligament reconstruction reduces pathologic laxity, improves lower-leg function, and minimizes flexion contracture and effusion.


The Leeds-Keio prosthesis in chronic anterior cruciate deficiency.

A woven polyester graft is used in chronic anterior cruciate instability. Twenty-five patients were reviewed with an average follow-up period of almost five years. The patients were assessed in terms of function, clinical examination, and residual laxity. The results showed that four could be classified as excellent, 16 good, and four poor. Fifty-two percent of patients returned to their preaccident level of activity, and there did not appear to be any evidence of increasing laxity with time. All patients had a good range of flexion with no extension loss. This prosthesis, along with its unique method of fixation, offers a simple alternative to patellar tendon or soft tissue reconstructions in the chronic anterior cruciate-deficient knee.


Revision surgery in clubfeet.

The reoperated clubfeet of 29 children aged one to 12 years were reviewed. The surgical procedure most often used in revision surgery was recomplete soft-tissue release alone or combined with plantar release, calcaneocuboid fusion, and capsulotomies of the navicular-first cuneiform-first metatarsal joint. In 27 of 29 feet, acceptable results were achieved. Nineteen were excellent and good results. An algorithm that suggests surgical solutions to a variety of clubfoot deformities in different age groups has been developed, as well as an objective rating system, to evaluate the long-term results of revision surgery of clubfeet.


Subtrochanteric fractures of the femur. Results of treatment by interlocking nailing.

Ninety-five subtrochanteric femoral fractures were treated with an interlocking nail. There were 69 closed and 26 open fractures. This injury was the result of high-energy trauma in 77% of the cases. The average time to healing was 25 weeks. There were three delayed unions, one nonunion, and six malunions. Essentially all nonpathologic, subtrochanteric femur fractures can be stabilized by interlocking nailing, regardless of the fracture pattern or degree of comminution. Favorable mechanical characteristics of interlocking nails have eliminated the requirement of surgically reconstituting the medial femoral cortex. Closed interlocking nailing is the preferred treatment for subtrochanteric fractures of the femur resulting from trauma.


Proximal femoral bone density and its correlation to fracture load and hip-screw penetration load.

The bone mineral density of 22 random, fresh proximal human femora was estimated by roentgenography using the Singh index (SI) and measured using a regional bone mineral density computed tomographic protocol. Uniaxial compression was used to produce an impacted subcapital fracture. The femoral heads then were isolated and mounted on a sliding screw plate compression device and loaded to failure in a push-out or hip-screw penetration mode. Wide intraobserver variation, poor reproducibility, and poor prediction of the experimental fracture properties of the proximal femur were noted for SI values. Regional bone mineral density provided a reliable estimate of both the gross fracture loads and hip-screw penetration loads. In addition, there was a high correlation between trabecular density and the experimental fracture properties of the proximal femur. Therefore, The validity of the SI as an indicator of the mechanical properties of the proximal femur should be reconsidered.


Rupture of the symphysis pubis during labor.

Two cases of spontaneous rupture of the symphysis pubis (SP) during delivery are reported. The separations were associated with considerable pain, swelling, and tenderness over the symphysis pubis and were confirmed roentgenographically. Both patients were treated conservatively with bed rest, mostly in the lateral decubitus position, within pelvic binders. Immobilization was discontinued when they were pain free. The SP separations remained in reduced positions. The patients were essentially asymptomatic and walked normally. Conservative treatment followed by early mobilization is adequate treatment for SP separations.


Femoral artery thrombosis after open reduction of an acetabular fracture.

The increasingly popular ilioinguinal anterior approach for select fractures of the acetabulum provides excellent exposure with minimal soft tissue dissection. Vascular complications reported with this procedure, although infrequent, are usually quite pronounced in their presentation. The authors encountered a more subtle case of femoral artery thrombosis secondary to vessel retraction while using this approach. The susceptibility of major vessels to thrombus formation is noteworthy. The precautions, and the close postoperative monitoring necessary to detect such vascular lesions, are emphasized.


Reversible vasospasm in association with the use of heparin and dihydroergotamine.

A case of reversible vasospasm is reported in a 54-year-old man with a closed bimalleolar ankle fracture. On admission the patient had normal distal pulses and laboratory studies. He was a heavy smoker who continued to smoke in the hospital. Deep venous thrombosis (DVT) prophylaxis included dihydroergotamine and heparin (DHE-H). In the early postoperative period, marked spasm of all three arteries developed on the operative side. Smoking privileges and DHE-H were discontinued. The vasospasm resolved after intraarterial nitroglycerin. This case suggests an infrequent but potentially limb-threatening complication of DHE-H.


A simultaneous distal phalanx avulsion fracture with profundus tendon avulsion. A case report and review of the literature.

Avulsion injuries of the flexor digitorum profundus are fairly common injuries, yet simultaneous avulsion fractures of the insertion of this tendon associated with rupture of the tendon from the bony fragment is rarely described and is more complicated. In the 24-year-old athlete, the injury was classified according to the system of Leddy and Packer. The authors' method of treatment is also described. Similar cases presented in the literature are reported, with emphasis on pathomechanism, physical findings, and surgical repair method. In this rare injury, stabilization of the distal interphalangeal joint is necessary even at the expense of early motion.


Proximal tibial skeletal traction for femoral shaft fractures in children. Treatment to discard or retain.

A proximal tibial skeletal traction in the treatment of femoral shaft fractures in the growing child has been reported to result in complications such as knee pain, knee joint subluxation, and growth disturbance. For the last 15 years, the authors used a single screw (instead of the Kirschner wire) inserted in the tibia perpendicular to the surface and well below the tibial tubercle physis. With the traction applied to this screw and the leg in a 90-90 position or resting on a Braun splint, none of the previously described complications were observed. This modification of the proximal tibial skeletal traction is a simple, quick, and safe method in the treatment of femoral shaft fractures in children.


Primary Hodgkin's disease of bone. A report of two cases in adolescents and review of the literature.

The presentation of Hodgkin's disease as a primary bony lesion is unusual. Seventeen such cases have been reported, only three of which appear in the orthopedic literature. The prognosis for survival in these patients is poor, possibly because of difficulty in arriving at the correct early diagnosis. In two adolescent girls (ages 12 and 17) with primary Hodgkin's disease of bone, the diagnosis was made with uncertainty or delay. One of the patients died and the other has progressive disease, two and one-half years after the diagnosis was established. Earlier recognition may lead to better outcomes.


Magnetic resonance imaging of pigmented villonodular synovitis in subtalar joint. Report of a case.

Pigmented villonodular synovitis (PVNS) is rare in the foot; however, it developed in the subtalar joint extending around the ankle of a 24-year-old man. The diagnosis was made by a combination of clinical findings, most notably the aspiration of the synovial fluid. Magnetic resonance imaging was most useful in showing the extent of the soft-tissue mass before surgery. Low-signal intensity of the mass, featured on both T1- and T2-weighted images, was suggestive of PVNS.


Tibial rotational osteotomy for idiopathic torsion. A comparison of the proximal and distal osteotomy levels.

A retrospective analysis was done of 52 rotational tibial osteotomies (RTOs) performed on 35 patients with severe idiopathic tibial torsion. Thirty-nine osteotomies were performed at the proximal or midtibial level. Thirteen were performed at the distal tibial level with a technique previously described by one of the authors. Serious complications occurred in five (13%) of the proximal and in none of the distal RTOs. For severe and persisting idiopathic tibial torsion, the authors recommend correction by RTO at the distal level. Proximal level osteotomy is indicated only when a varus or valgus deformity required concurrent correction.


Why do most surgical incisions require lengthening? How to avoid it.

When an incision is retracted, it shortens because skin does not actually stretch--it only shifts. A mathematical model accurately predicted operating room experience. Average retraction of 30-50% shortens an incision by 15%. Therefore, an incision to expose fixed bony landmarks should be 15% longer than the distance between them.


Biomechanical effects of a new point configuration and a modified cross-sectional configuration in Kirschner-wire fixation.

Kirschner-type wires (K-wires) comprising three different point configurations and two cross-sectional shaft configurations were drilled into bone to determine the insertional force required and the holding power achieved with each type. Round K-wires with either a diamond point or a high rake-angle trocar point were compared with each other and with C-wires, which have a rounded square cross section and a short diamond point. The K-wires performed superiorly to C-wires with respect to bone penetration. The K-wires demonstrated about twice as much holding power as the C-wires. No significant differences in performance were detected between the diamond-tipped and trocar-tipped K-wires with respect to either insertion or pull-out. For all three wire-tip combinations, insertion was facilitated by faster drill speed, but holding strength was superior with slower speed. For ease of insertion, even at oblique angles, and for maximum holding strength, the high-rake angle, trocar-tipped K wire is best.


Effect of electrostimulation on denervated muscle.

The influence of electrostimulation on denervated and reinnervated muscle was investigated. First, the left peroneal nerve was severed in rats. Wet weight and muscle fiber diameter of denervated anterior tibial muscle was compared as a percentage of contralateral muscle in stimulated and non-stimulated rats. In a second experiment, four weeks after the peroneal nerve was severed, the tibial nerve was cross-sutured to the distal stump of the peroneal nerve. Electrostimulation was continued in rats that had electrostimulation before nerve-crossing. Recovery of wet weight was assessed at eight weeks and at one year after nerve-crossing. The mean decrease in weight and fiber diameter of the denervated muscle was significantly less in the group that was electrostimulated for eight weeks. Recovery of weight of reinnervated muscle was significantly better in the electrostimulated group. Electrostimulation of denervated muscle retarded denervation atrophy and improved recovery after reinnervation.


Articular cartilage thickness and glycosaminoglycan distribution in the canine knee joint after strenuous running exercise.

The influences of the strenuous running training program on the knee joint articular cartilage was studied in six female beagle dogs. At the age of 15 weeks, the dogs started running on a treadmill inclined 15 degrees uphill. Thereafter, the dogs were trained for 40 weeks, five times a week. For the final 15 weeks, the dogs ran 20 km/day. Six age-matched female beagles served as controls. The cartilage surfaces were intact after the running exercise. The training reduced the thickness of the uncalcified cartilage by 6% in the medial femoral condyle. The glycosaminoglycan concentration was reduced an average of 11% on the summits of the femoral condyles. The reduction was most pronounced (41%) in the superficial 50-micron cartilage zone. In other regions of the knee, such a decrease of glycosaminoglycans was not observed. A shift to strenuous running voided the increase in cartilage thickness and proteoglycan content previously observed after moderate running. Strenuous running induced marked depletion of proteoglycans from the superficial layer of the femoral condyles at sites subjected to highest impact loads.


Surgical treatment of the child's flatfoot.

A series of 234 surgically treated flatfoot in children were treated by means of a double incision and by the placing of an orthosis in the sinus tarsi.


LD hip arthroplasty. Design concepts and first clinical trials of a new modular system.

The new LD modular hip arthroplasty is made of Ti6A14V. The acetabular component has a hemispheric expansive metallic ring and a polyethylene nucleus in the shape of a cone segment. Since June 1988, when the clinical trials began, 352 arthroplasties have been performed with 112 total hip arthroplasties among them. Only 60 noncemented total hip arthroplasties, with the longest follow-up evaluation reaching 24 months, were analyzed. Patients with revision operations were excluded. The results have been evaluated using the Merle D'Aubigne scoring scale. Good results were found in 86% of cases. Pain improved markedly at three months in the postoperative period. At six months, the Trendelenburg sign was negative in 76% and positive in 12%. The Duchenne sign was positive in 11%. Major complications included three dislocations, two acetabular component revisions caused by initial malposition, one external popliteal nerve palsy, one deep infection, and two periprosthetic fractures. No acetabular migrations have been found. There are six femoral sinkings of less than 1 cm. Heterotopic ossifications Grade II-III appear in 24% of cases. The results to date are evaluated clinically and radiologically. The acetabular design has proved efficient, and the femoral components show a low incidence of stress shielding.


Five-year follow-up evaluation of the noncemented press-fit titanium hip-joint endoprosthesis.

A series of 260 noncemented total hip arthroplasties with a titanium alloy stem and fixation by the Zweymüller press-fit and an Endler polyethylene threaded cup was reviewed in detail. The minimum follow-up period was 48 months and the maximum 72 months, with an average of 60 months. A scale from zero to five points was applied to evaluate pain, mobility, and motion for a total possible accumulation of 15 points. The global results of the different etiologic groups (arthrosis, femoral head necrosis, rheumatoid arthritis, and subcapital hip fractures) have been very good and good (12-15 points) in 67.5% of the cases and fairly good and bad in 32.3%. These results have been better in femoral head necrosis than in arthrosis or rheumatoid arthritis, but not as good in subcapital hip fractures. The age groups below 60 had better results than the above 60 groups. The Singh index higher than 3 was correlated with better-than-average results. The polyethylene cup migrated horizontally (more than 4 mm) in 7.6% of the cases and vertically (more than 5 mm) in 10%. The non-evolutionary cortical remodelation of the femur does not influence the results. Prosthetic stem sinking less than 4 mm has been found in 62% of the cases, from 4 to 9 mm in 21%, and greater than 9 mm in 6%. No alterations with clinical consequences attributable to stress-shielding have been detected.


Occipital-cervical instability.

A retrospective clinicoroentgenographic study was done on 26 patients with atlantoaxial instability, 17 traumatic and nine nontraumatic. All were treated by means of surgical C1-C2 and occipital-C2 stabilization. The traumatic instability was associated with lesions of the odontoid process and the atlas transverse ligament. Instability may be endogenous or associated with fracture of the atlas. Surgical indication was determined by the level of the fracture line, neurologic symptoms, age, and presence of multiple lesions. C1-C2 stabilization by means of wiring and iliac graft was the selected treatment. Fusion between the occipital and C2 segment was indicated in case of irreducible dens pseudoarthrosis. Fracture on the os odontoideum was very unstable and required greater C1-C2 fusion. Nontraumatic C1-C2 instability was either congenital or secondary to pathologic fractures. Rheumatoid arthritis, which produces anterior displacement of the atlas over the dens to more than 10 mm, neurologic symptoms, or untreatable pain must be stabilized by means of C1-C2 fusion. When elevation of the dens or irreducible displacement of the atlas exists, the results were relatively poor. Tumorous instability produced pathologic fracture of the body of the axis and had to be treated with C1-C2 wiring on bone cement. Down's syndrome instability required occipitoaxial fusion and strict postoperative immobilization.


Clinical and ultrastructural analysis of failures in chemonucleolysis.

A series of 12 patients with failed chemonucleolysis were analyzed to determine the various causes of such failures. The ultrastructural findings observed in laminectomy specimens did not account for the failure in the enzyme treatment. The findings suggested deficient cellular nutrition secondary to enzymatic histolysis of the nucleus pulposus.


Internal fixation of ulnar fractures by locking nail.

Fractures and dislocations of the forearm are commonly observed in trauma clinics. With time, there will probably be significant increases in fractures of the forearm associated with traffic and sports. The efficacy of the treatment of ulnar fractures by a new locking nail, developed by Lefevre in Strasbourg, was tested in 20 patients. The fractures were severely displaced ulnae or both bones of the forearm. The minimum follow-up period was six months. The average age of the patients was 33.5 years (range, 14-77 years). The nail is placed into the ulna proximally. Locking is achieved by two screws placed at the proximal and distal end of the nail. The healing time for the fractures of both bones of the forearm ranged from 75 days to 20 weeks, with an average of 15 weeks. Healing time for the ulnar fractures ranged from eight to 20 weeks, with an average of ten weeks. The advantages of this nail were easy closed technique, compression effects at the fracture site, and enough stability so that an external support and tourniquet, in isolated ulnar fractures, were not necessary.


Treatment of the femoral and tibial fractures with Grosse and Kempf locking nails.

In a series of 104 femoral and 50 tibioendomedullary nailings using Grosse-Kempf (G-F) locking nails, 24% of femoral fractures and 12% of tibial fractures were comminuted; 48% of the patients had multiple injuries. The nail was locked at proximal and distal levels in 54% of the cases for the femur. Dynamization of the nail was carried out at an average of 12 weeks. Nonweight-bearing was imposed for both series from three weeks to three months. Bone healing was achieved before six months in 100% of tibial fractures. Following Thoressen criteria, the results of femoral cases were all excellent and good; the percentage reached 96% for tibial cases. The G-F nail is suitable for high-energy, comminuted fractures.


Condylocephalic nailing in pertrochanteric fractures.

Because of the spectacular increase in the number of fractures of the proximal end of the femur, especially in the elderly, there is a great interest to find surgical techniques that are simple, decrease mortality, and restore early the functional status of the patients, thus reducing the hospital stay. From 1969 until 1989, 2660 fractures were treated with the Küntscher condylocephalic (KC) nail. The mean age of patients was 79 years, and the general condition was considered to be good in only 23%. Death in the ensuing three months occurred in 12.5%. Complications of the technique were supracondylar fractures (1.8%) and migrations of the nails (17.4%). Bone healing occurred at eight to 12 weeks. Only 15% of patients failed to walk. Mean cervicodiaphyseal postoperative angle was 155 degrees. As compared with other surgical techniques, the KC nail was easier to insert, in relatively less operating time, and knee problems of Ender's nail operations can be avoided. The KC nail was most suitable for the treatment of pertrochanteric fractures in elderly patients.


Correction of angular deformities by physeal distraction.

Physeal distraction is an alternative to more conventional treatments for the correction of angular deformities of the long bones. Twenty deformities of the femur and tibia, nine of which also involved associated shortening, were partially or completely corrected. In eight cases, there was physeal bony bridge. Complete correction of the angular deformity was achieved in 17 patients, and in seven patients, more than 80% correction was achieved. There were complications in four patients that hindered complete correction of the deformity, or shortening, or both. The external control of the correction until consolidation occurs is progressive and fairly noninvasive. The method allows external control of the correction until consolidation; it acts at the site of the deformity itself and permits lengthening and angular correction during therapy. In deformities with a physeal bony bridge, correction can be achieved with physeal distraction alone, prior resection of the bridge is not unnecessary. The technique is indicated in cases of angular deformities in patients nearing skeletal maturity and particularly in subjects in whom there is associated shortening.


Complications of anterior cervical disk removal and fusion.

Surgeons favoring fusion believe that removal of the disk alone can result in painful spondylosis, eventually requiring fusion. Surgeons not favoring fusion eliminate painful neuralgia from damage to the anterior femoral cutaneous nerve as well as painful donor site scars. Also eliminated are painful pseudarthrosis and degenerative problems. Graft collapse and displacement are uncommon if three-sided iliac grafts are used. Rarely, if ever, is it necessary to fix the graft in place with wire silk sutures. Fortunately, complications of cervical spine surgery are uncommon.


Posterolateral lumbar and lumbosacral fusion with and without pedicle screw internal fixation.

Forty-seven patients who had lumbar or lumbosacral fusion with or without pedicle screw internal fixation by one surgeon for treatment of degenerative lumbar disease with clinical instability were retrospectively reviewed by an independent observer. Eighteen of the 21 patients whose fusions were internally fixed with the Variable Spinal Plating (VSP) system were available for review. A control group consisted of 27 patients who had fusion without internal fixation. The rate of pseudarthrosis did not significantly differ between the two groups (VSP group, 22%; versus control group, 26%). Twelve (67%) of the 18 patients treated with fusion and VSP instrumentation were considered to have had a good or excellent outcome, whereas 19 (70%) of the 27 patients treated by fusion without internal fixation had good or excellent results. Two VSP-instrumented patients had postoperative leg dysesthesias, whereas this complication was not observed in the control group. Bilateral posterolateral lumbar or lumbosacral fusion without internal fixation is as effective as and safer than fusion with pedicle screw instrumentation.


An electromyographic analysis of the shoulder during cones and planes of arm motion.

Shoulder motion has traditionally been described in reference to arbitrarily defined planes of motion (e.g., sagittal/flexion, coronal/abduction). This study examined shoulder muscle recruitment during conical arm movements, which include all planes of motion. Electromyographic (EMG) data was collected with intramuscular wire electrodes from ten muscles in five normal volunteers. Each muscle showed peak EMG activity in association with a direction of action consistent with its anatomic alignment. These findings were similar for movements in both the sagittal and coronal planes, calling into question conventionally held designations of shoulder muscles as flexors and abductors. Muscle recruitment was as follows: Clavicular pectoralis major, to move the arm medially along the horizontal; anterior deltoid, to move the arm obliquely upward inclined toward the midline; middle deltoid, to move the arm obliquely upward inclined away from the midline; posterior deltoid, to move the arm laterally along the horizontal; and teres major and latissimus dorsi, to move the arm obliquely downward away from the midline. Rotator cuff muscles were maximally active during elevation, consistent with the concept of a force couple.


Incomplete rotator cuff tears. Results of operative treatment.

Thirty-eight shoulders of 36 patients with incomplete rotator cuff tears surgically repaired were evaluated, with an average follow-up period of 4.9 years. The average age at operation was 52.2 years. Three types of incomplete tears were identified: superficial (12 shoulders), intratendinous (three), and deep surface tears (23). Full-thickness cuff involving the lesion was resected and repaired by side-to-side suture (13 shoulders), side-to-bone suture (eight), fascial patch grafting (16), or side-to-bone suture with fascial patch grafting (one). The overall results were satisfactory in 31 shoulders (82%). The results were not affected by the tear types, operative methods, or follow-up period. The patients with poor results were associated with major complications other than rotator cuff tears or with insufficient resection of the damaged cuff. When the full-thickness cuff involving the lesion is completely resected and repaired, long-term satisfactory results can be anticipated in a high percentage of patients regardless of tear types.


Autotraction stress roentgenography for demonstration anterior and inferior instability of the shoulder joint.

A form of stress roentgenography is presented for the diagnosis of anterior and inferior shoulder instabilities. Stress is induced by anterioinferior traction concentrated on the shoulder during extension of the flexed hip, when patients hold their legs on the side being examined, with both hands. The anterior and inferior shifts of the humeral head in relation to the glenoid fossa then are measured from anteroposterior and modified axillary roentgenograms. This method was employed in 16 shoulders with recurrent anterior dislocation, 11 recurrent anterior subluxations, nine multidirectional instabilities, and 19 control shoulders. Mean anterior translations were 3 mm and 5 mm, and inferior translations were 7 mm and 10 mm for the control and recurrent dislocation groups, respectively. There were statistically no significant differences between those groups. In the recurrent anterior subluxations, the corresponding translations were of a completely different order, 21 mm and 19 mm, respectively, allowing the distinction from the controls and recurrent anterior dislocations in most cases. The shifts found in multidirectional instabilities, averaging 27 mm and 26 mm, respectively, were significantly greater than for the recurrent subluxations, but the differences were not great enough for accurate differential diagnosis in individual cases. Autotraction stress roentgenography of the shoulder may be of use in the diagnosis of recurrent anterior subluxations and anteroinferior multidirectional instabilities. It also gives good general views of the looseness of the glenohumeral joint.


Neurologic complications and lumbar laminectomy. A standardized approach to the multiply-operated lumbar spine.

Even the careful and knowledgeable spine surgeon will encounter a variety of neurologic complications during and after routine lumbar laminectomy. These include dural and nerve root injuries; cauda equina syndrome; and formation of scar tissue, extradural and intradural (arachnoiditis). The surgeon must be prepared to identify each of these problems and deal with them effectively at the time of the procedure and in the immediate postoperative and follow-up periods. The physician evaluating the multiply-operated lumbar spine patient must use an organized approach. The origin of the problem in most instances is a faulty decision to perform the original operative procedure. Further surgery on an "exploratory" basis is not warranted in any situation and most likely will lead only to further disability. There should be definite objective findings to substantiate the patient's symptoms. The etiology of each patient's symptoms. must be accurately localized and identified. Medical status and psychosocial situation--as well as orthopedic and neurologic findings--should be evaluated at the time of the initial consultation. Once the spine is identified as the probable source of symptoms, specific features should be sought in the patient's clinical history, physical examination, and roentgenographic studies. The number of previous operations, length of pain-free interval, and predominance of leg versus back pain are the major historic signposts. The presence of a tension sign and the neurologic findings are the focal points of the physical examination. Plain roentgenograms, motion films, water-soluble myelogram, computed axial tomography, and magnetic resonance imaging with contrast have specific roles in the workup.(ABSTRACT TRUNCATED AT 250 WORDS)


Fluoroscopic comparison of kinematic patterns in massive rotator cuff tears. A suspension bridge model.

Twelve shoulders with known massive rotator cuff tears were imaged fluoroscopically. The observed kinematic patterns were correlated with the known locations of the rotator cuff tears. Three kinematic patterns emerged: Type I, stable fulcrum kinematics associated with tears of the superior rotator cuff (supraspinatus and a portion of the infraspinatus); Type II, unstable fulcrum kinematics associated with tears that involved virtually all of the superior and posterior rotator cuff; and Type III, captured fulcrum kinematics associated with massive tears that involved the supraspinatus, a major portion of the posterior rotator cuff, and a major portion of the subscapularis. In Type III, an "awning effect" of the acromion was observed to influence active motion. Based on the recorded kinematic patterns, a biomechanical model was developed comparing the rotator cuff tear to a suspension bridge (loaded cable). A biomechanical analysis of forces acting on the rotator cuff according to this model yielded data that supported the contention that certain rotator cuff tears in older individuals may be adequately treated with debridement and decompression, without repair.


Irreducible "pulled elbow" in a child. A case report.

"Pulled elbow" is a common pediatric injury that occurs when axial traction is applied to an arm that is extended while the forearm is pronated. These forces can create a transverse tear in the annular ligament, which permits subluxation of the radial head. In most cases, closed reduction can be performed by supinating the forearm and flexing the elbow. In the case of a five-year-old boy, surgical reduction of this injury was necessary to reduce the subluxated radial head.


Osteochondritis dissecans of the elbow. A long-term follow-up study.

Thirty-one patients with osteochondritis dissecans of the capitellum humeri were followed for an average of 23 years. There were symptoms in about half of the elbows at the follow-up examination. Impaired motion and pain on effort were the most common complaints. Roentgenographic signs of degenerative joint disease were present in more than half of the elbows and correlated with a reduced range of motion. The diameter of the radial head increased in comparison with the contralateral elbow in two thirds of the patients.


The fallen wire sign. An indicator of hip prosthetic loosening.

Trochanteric osteotomy is commonly performed during total hip arthroplasty. Subsequent fatigue fracture of the osteotomy wires, although common, usually has no clinical sequelae. In four cases, wire fragments migrated down the medullary cavity of the femur, in the space created by a loosened femoral component. This roentgenographic observation seems not to have been previously reported and is a definitive sign of femoral prosthesis loosening.


Cementless total hip arthroplasty in renal transplant patients.

Twenty-seven cementless total hip arthroplasties were performed in 17 steroid-dependent renal transplant patients. The average age at operation was 39 years, and the average daily dose of prednisone was 10.9 mg. At a mean of 48 months post-surgery, all patients had good to excellent hip ratings on clinical examination and the results compared favorably with 235 non-steroid-dependent age-matched patients using the identical prosthetic hip system. The results of this study suggest that long-term immunosuppression does not prevent bone ingrowth. Noncemented total hip arthroplasty appears to be a reasonable therapeutic option for end-stage osteonecrosis in steroid-dependent renal transplant patients.


Hip fracture-dislocation with transepiphyseal separation. Case report and literature review.

Fracture-dislocation of the hip is an infrequent injury in adolescence. In combination with transepiphyseal separation of the capital femoral epiphysis, the injury is rare and catastrophic. A review of orthopaedic literature shows varied recommendations as to treatment approaches. The most recent articles have suggested that open reduction through a posterior approach and internal fixation is the best way to treat this problem initially. Later reconstructive measures are usually required because this injury often leads to avascular necrosis of the femoral head. The patient and family should be advised that the prognosis after such a fracture-dislocation is not good. Potential reconstructive measures after collapse of the femoral head include total hip arthroplasty and hip arthrodesis. Total hip arthroplasty is not a reliable means of providing a long-term painless joint in an active adolescent with one-joint disease. Hip arthrodesis has been shown to be a good alternative treatment for patients who develop avascular necrosis after this severe injury.


Hip pain caused by buttock claudication. Relief of symptoms by transluminal angioplasty.

Two patients with severe hip pain proved to have buttock claudication resulting from isolated stenosis of the hypogastric artery. This diagnosis may be elusive if distal pulses are palpable, directing the clinician's suspicion away from vascular pathology. Diagnosis requires angiography. The patients were successfully treated by transluminal angioplasty. Angioplasty is the initial treatment of choice for these patients because the hypogastric artery is usually readily and safely accessible from either the femoral or axillary artery.


Effect of functional neuromuscular stimulation on anterior tibial compartment pressure.

Intramuscular pressures in the anterior tibial compartment were measured in five paraplegic subjects who used functional neuromuscular stimulation (FNS) by percutaneous intramuscular electrodes for exercise and walking. Effects of two types of stimulation pattern were tested: continuous stimulation for 15 minutes and cyclic stimulation for 60 minutes, with duty cycle and stimulation levels similar to that used in walking. Resting compartment pressure levels before stimulation were less than 7 mm Hg in all subjects. Continuous stimulation at maximum parameters produced compartment pressure levels up to 116 mm Hg, but these were not sustained. They decreased to below 40 mm Hg within one minute in all except one subject, who was having repeated spasms. Cyclical stimulation raised mean muscle pressure to between 70 and 80 mm Hg in two patients. Muscle contraction pressure increased to 153 mm Hg in one patient, but was below 100 mm Hg in all patients after two minutes, except during spasms. Muscle relaxation pressure stayed below 30 mm Hg in four subjects. After stimulation, the pressure returned to prestimulation levels within 15 minutes. These results suggest that FNS subjects are not in danger of developing compartment syndrome. Nevertheless, occasional testing of compartment pressures is recommended, especially when activity levels rise significantly.


Forced march-induced peroneal compartment syndrome. A report of two cases.

Isolated exertional peroneal compartment syndrome is rare. Two cases are described after prolonged forced march in highly conditioned United States Marines. Measured compartment pressures were over 100 mm Hg. No permanent impairment resulted after surgical decompression.


Posterior tibial subluxation of the posterior cruciate-deficient knee.

Ten subjects with unilateral posterior cruciate ligament-deficient knees were studied, comparing the knee mechanics of the affected knee with the mechanics of the opposite normal knee. The static squat test was used to determine knee forces and moments through measurements made on roentgenograms. Statistically significant increases occurred in posterior translation of the tibia in all knees at high knee flexion angles, but not uniformly at low knee flexion angles. The results suggest that posterior tibial subluxation occurs in vivo during certain activities of daily living. Posterior tibial subluxation occurred in positions of knee flexion near 70 degrees, establishing a new equilibrium for the system where tibiofemoral joint compression force (approximately four times one-half body weight) remained an order of magnitude greater than tibiofemoral shear forces (approximately 10% of one-half body weight).


Results following treatment of traumatic dislocations of the knee joint.

In a retrospective study, 31 patients were identified over a period of 25 years as having sustained traumatic knee dislocations without associated fractures. Three patients had early amputation secondary to vascular complications. Ten popliteal artery disruptions and five peroneal nerve palsies were diagnosed. At the time of follow-up evaluation (average, 40 months), 16 patients were examined. Operatively treated patients (n = 6) tended to have better motion (129 degrees) than nonoperatively treated patients (108 degrees). Varus instability was seen in only two patients treated nonoperatively. All patients except one experienced persistent functional limitations. Roentgenographic follow-up examination showed similar degenerative changes in both groups.


Uncemented intramedullary fixation of implants using polyethylene sleeves. A roentgenographic study.

Forty-three prostheses with noncemented, high-molecular-weight, polyethylene-sleeved components were used in the treatment of bone tumors around the knee in growing children. The average age of the patients was 11 years. There were 27 boys and 16 girls. There were 17 sleeved components in the distal femur and 26 in the proximal tibia. The average follow-up time was 27 months. The roentgenograms were nominally obtained at three, six, 12, 18, and 24 months, and irregularly thereafter, and were assessed using a zonal evaluation scheme. A sclerotic interface around the polyethylene sleeves invariably developed and progressed in density up to 28 months postoperatively. There were significant zonal differences in sclerosis, particularly between the plateau and the mid-sleeve zone. Only in one patient did a sleeve become loose and require revision.


The cemented unicondylar knee arthroplasty. An in vitro comparison of three cement techniques.

Three cementation techniques were investigated to determine their effect on initial fixation of unicondylar tibial components. Twenty-one anatomic specimens were divided into three groups. In Groups A and B, the medial tibial plateau was minimally resected. Group A was drill interdigitated and pulse lavaged, Group B was left "as cut". In Group C, the articular cartilage was curetted, exposing the subchondral bone entirely. An Ortholoc II unicondylar prosthesis was cemented onto the tibias, after which a 981-N load was applied anteromedially at 1 Hz for 10,000 cycles. Measurements for anterior and posterior micromotion were taken at the first cycle, every ten cycles for the first 100 cycles, every 100 cycles for the first 1000, and every 250 cycles thereafter. Measurements for anterior subsidence and posterior liftoff were taken after every 1000 cycles. Group A was found to be significantly better than Group B in anterior micromotion, posterior micromotion, and posterior liftoff in all load cycles. Group A was also found to be significantly better than Group C in anterior micromotion, posterior micromotion, and posterior liftoff in all load cycles. The performance of Groups B and C was highly variable. Both groups had specimens with extreme micromotions in response to low loads. Group A provided consistent and superior results. This study shows that cementation techniques employing multiple-drill-hole interdigitation and pulse lavage produce rigid initial fixation and consistent excellent results. Cementing to the smooth subchondral bone or unlavaged cancellous bone was unreliable.


The management of fixed flexion contractures during total knee arthroplasty.

Fifty-one knees in 40 patients with joint surface degeneration accompanied by fixed flexion contractures (FFC) greater than 20 degrees were treated with total knee arthroplasty using a minimally constrained posterior cruciate ligament retaining prosthesis. Special techniques were employed in an attempt to achieve maximal correction at the time of surgery. The residual FFC measured 3.1 degrees at the completion of the arthroplasty, 10.1 degrees at three months, and 7 degrees at two years. At 55 months postoperatively, the FFC for the osteoarthrotic group had improved from 25.5 degrees to 3.6 degrees, whereas the rheumatoid group improved from 28.7 degrees to 8.6 degrees. The average knee score for the osteoarthrotic group was 89 compared with 81 for the rheumatoid group. Knees that were left with greater residual FFC at the completion of the arthroplasty were found to have greater residual FFC at the latest review.


Complete knee dislocation without posterior cruciate ligament disruption. A report of four cases and review of the literature.

Complete knee dislocation usually causes disruption of both the anterior and posterior cruciate ligaments. Four cases of complete knee dislocation without posterior cruciate ligament (PCL) disruption are reported. All cases involved either anterior or anteromedial dislocation with anterior cruciate ligament disruption and collateral ligament injury, but without posterior cruciate disruption. This is an uncommon finding in complete dislocation of the knee. The PCL may occasionally be spared significant injury in anterior type dislocations, however, thus favorably affecting treatment options.


Surgical excision of hemophilic pseudotumor of the ilium.

The iliac hemophilic pseudotumor is a rare complication of hemophilia occurring in 1-2% of patients with Factor VIII or Factor IX deficiency. It is frequently disabling and life threatening. This report presents a comparative study of postoperative results of two cases of hemophilic pseudotumor of ilium. One patient undergoing partial resection showed a favorable postoperative course, whereas the patient with complete resection of the pseudotumor died of postoperative bleeding and sepsis. Studies on the postoperative results of these two cases indicate that careful preoperative consideration of tumor size and degree of infiltration is of the utmost importance in operative management. Early excision of tumors eliminates the possibility of endogenous infection. Even partial resection of huge tumors, leaving the lateral wall intact for compression, can promote recovery of functions.


Lower-limb proprioception in above-knee amputees.

A proprioception measurement system was designed and constructed to evaluate lower-limb knee joint proprioception in ten above-knee amputees. The system permitted the testing of subjects in a position simulating late swing phase of gait. The threshold for detection of slow passive motion and the ability to reproduce specified lower-limb positions were recorded for the sound and the prosthetic limbs of the subjects. A significant difference was detected between prosthetic and sound limb passive motion detection threshold; however, no difference was found between prosthetic and sound limb passive motion reproduction. This finding suggests the importance of hip joint motion appreciation in the amputees' proprioception of the prosthetic knee joint when these motions are associated. Prosthetic limb passive motion reproduction error decreased with age, suggesting that the amputees may improve their ability to use remaining lower limb proprioceptive mechanisms to compensate for the loss of anatomic knee joint structures.


Managing complications of posterior spinal instrumentation and fusion.

Complications of posterior spinal instrumentation for adolescent idiopathic scoliosis are often preventable. Preoperative planning helps to minimize intraoperative and postoperative problems. Late recurrence of rotational deformity (crankshaft) in skeletally immature patients can be prevented by adding anterior surgery. Intraoperative complications are minimized by controlled hypotensive anesthesia and sequencing of surgical steps to allow for autocoagulation, reducing blood loss. Use of spinal cord monitoring, Stagnara wakeup test, and careful distraction decreases the risk of neurologic deficit. Good hook-site preparation helps avoid dural tears. The incidence of postoperative pneumothorax and hemothorax is decreased by careful hook attachment, avoiding pleural penetration, judicious use of rib excision thoracoplasty, and roentgenographic verification of central venous pressure line position. Postoperative recommendations include bed position at 30 degrees, frequent log rolling, incentive spirometry, early sitting and standing, early Foley catheter and nasogastric tube removal, prophylactic antibiotics, and prompt attention to wound infections. Postoperative orthotic wear, prescribed exercise, and activity restriction decrease the risk of early instrumentation failure and help correct early postoperative trunk imbalance. The late complications include suspected pseudarthrosis; this should be surgically treated again if there is persistent pain or marked loss of curve correction.


Force- and moment-generating capacity of lower-extremity muscles before and after tendon lengthening.

A computer model of the human lower extremity was developed to study how surgical lengthening of tendon affects the force- and moment-generating capacity of the muscles. This model computes the maximum isometric force and the resulting joint moments that each muscle-tendon complex can develop at any body position. Tendon lengthenings were simulated by increasing the tendon length of each muscle-tendon complex and computing the change in the maximum isometric muscle force and joint moments at a specific body position. These simulations showed that the forces and moments developed by the ankle plantarflexors are extremely sensitive to changes in tendon length. For example, at a body position corresponding to the midstance phase of gait, the maximum isometric moment generated by soleus decreased 30% with a 1-cm increase in tendon length, and 85% with a 2-cm increase in tendon length. In contrast, 1- and 2-cm increases in iliopsoas tendon length decreased its hip flexion moment by only 4% and 9%, respectively. This article quantifies the sensitivity of muscle force and joint moments to changes in tendon length for the most commonly lengthened lower-extremity tendons. These results indicate how much each of these tendons should be lengthened to achieve an incremental decrease in muscle force or joint moment.


Holding power and reinforcement of cancellous screws in human bone.

The authors report an in vitro biomechanical evaluation of a biodegradable material that might be used for the reinforcement of surgical screws in fractures involving severely osteoporotic bone. The material is a particulate composite with a matrix phase consisting of a hydrolyzable prepolymer, polypropylene fumarate (PPF), crosslinked with methacrylate monomer, and a particulate phase consisting of tricalcium phosphate and calcium carbonate. Pullout force and stripping load of cancellous screws were determined along with screw pullout force before and after reinforcement with either polymethylmethacrylate (PMMA) or PPF composite. Pullout force was moderately correlated (R2 = 0.59) with apparent density by a power law relationship of the form 0.065p1.37-1.77. Stripping load was strongly correlated (R2 = 0.91) with apparent density by a power law of the form 0.13p1.35-93.8. Mean pullout force before and after reinforcement with PMMA was 382 +/- 100 N (mean +/- standard deviation) and 879 +/- 315 N, respectively. Mean pullout force before and after reinforcement with PPF composite was 571 +/- 294 N and 829 +/- 354 N, respectively. Although the increase in pullout force with cement reinforcement was highly significant in both cases, the magnitude of the increase did not depend on the type of cement. Thus PPF seems to provide reinforcement that is equivalent to that provided by PMMA.


A reproducible porcine vertebral fracture for biomechanical testing of spinal fixation devices.

To evaluate vertebral fracture fixation devices in the laboratory, it is necessary to produce identical and unstable fractures either in anatomic specimen or animal models. Consistent achievement of this goal has not been reported in the literature. This report presents a technique for the study of reproducibility for a particular vertebral fracture model. A precise anterior defect was created in a vertebra of each specimen drawn from a homogeneous population of mature sow spines. The spines were loaded to failure. Fracture reproducibility was shown by measurement of load and displacement, and confirmed by roentgenographic evaluation. The technique is easily applied to human specimens. Because there is a plethora of fracture fixation devices based on hooks, wires, or, more recently, plates and pedicle screws, the reliability of comparative testing of these devices in the laboratory requires an appropriate and reproducible fracture.


Rapidly destructive arthropathy of the hip. Studies on bone resorptive factors in joint fluid with a theory of pathogenesis.

The mechanism of joint destruction in rapidly destructive coxopathy was studied by analyzing bone resorptive factors in the joint fluid. Prostaglandins were found to play a partial role in joint destruction. Some cases of rapidly destructive coxopathy revealed elevated levels of interleukin-1 beta (IL-1 beta) in the joint fluid. Electrophoretic analysis of proteolytic enzymes in polyacrylamide gel containing sodium dodecyl sulfate and copolymerized gelatin demonstrated that the resorptively active peptides have relative molecular weights (M(r)) of approximately 92,000, 72,000, and lower than 60,000. Cultured cells from synovia obtained perioperatively secreted matrix metalloproteinase 2 (MMP-2) with an M(r) of 72,000 and matrix metalloproteinase 3(MMP-3) with an M(r) of 57,000. Synovial cells from the patients with coxarthrosis secreted fewer proteolytic enzymes. Prostaglandins, IL-1 beta, MMP-2, and MMP-3 could act synergetically as promotors in the rapid destruction of the hip joint.