Comparison of gait in patients following a computer-navigated minimally invasive anterior approach and a conventional posterolateral approach for total hip arthroplasty: a randomized controlled trial. Comparative study between computer assisted-navigation and conventional technique in minimally invasive surgery total knee arthroplasty, prospective control study. Midterm outcomes of electromagnetic computer-assisted navigation in minimally invasive total knee arthroplasty New two-incision minimally invasive total hip arthroplasty: comparison with the one-incision method Minimally Invasive versus Classic Procedures in Total Hip Arthroplasty: A Double-blind Randomized Controlled Trial Time course and extent of functional recovery during the first postoperative year after minimally invasive total hip arthroplasty with two different surgical approaches--a randomized controlled trial. Reduction in variability of acetabular cup abduction using computer assisted surgery: a prospective and randomized study. Computer-assisted total knee arthroplasty using mini midvastus or medial parapatellar approach technique Five-year follow-up of minimally invasive computer assisted total knee arthroplasty (MICATKA) versus conventional computer assisted total knee arthroplasty (CATKA) - A population matched study. Tackling the learning curve: comparison between the anterior, minimally invasive (Micro-hip®) and the lateral, transgluteal (Bauer) approach for primary total hip replacement Early thromboembolic events ≤1week after fast-track total hip and knee arthroplasty. Myocardial infarction following fast-track total hip and knee arthroplasty—incidence, time course, and risk factors: a prospective cohort study of 24,862 procedures Surgical access and damage extent after total hip arthroplasty influence early gait pattern and guide rehabilitation treatment. Robot‐assisted total hip arthroplasty: Clinical outcomes and complication rate Minimal invasive and computer-assisted total knee replacement compared with the minimal invasive technique: a prospective, randomized trial with short-term outcomes Minimally invasive total hip arthroplasty--our clinical experience. Minimal-invasive posterior approach for total hip arthroplasty versus standard lateral approach. Minimally invasive intermuscular approach does not improve outcomes in bipolar hemiarthroplasty for femoral neck fracture Radiographic Analysis of One-level Minimally Invasive Transforaminal Lumbar Interbody Fusion (MI-TLIF) With Unilateral Pedicle Screw Fixation for Lumbar Degenerative Diseases Comparison of radiographic alignment of imageless computer-assisted surgery vs conventional instrumentation in primary total knee arthroplasty. Antero-lateral minimal invasive (ALMI) approach for total hip arthroplasty technique and early results Randomized trial of computer-assisted knee arthroplasty: impact on clinical and radiographic outcomes.
Minimally invasive total hip arthroplasty ( MIS THA ) aims at minimizing damage to muscles and tendons to accelerate postoperative recovery . Computer navigation allows a precise prosthesis alignment without complete visualization of the bony l and marks during MIS THA . A r and omized controlled trial ( RCT ) was conducted to determine the effectiveness of a computer-navigated MIS anterior approach for THA compared to a conventional posterolateral THA technique on the restoration of physical functioning during recovery following surgery . Thirty-five patients underwent computer-navigated MIS THA via the anterior approach , and 40 patients underwent conventional THA using the conventional posterolateral approach .  Gait analysis was performed preoperatively , 6 weeks , and 3 and 6 months postoperatively using a body-fixed-sensor based gait analysis system . Walking speed , step length , cadence , and frontal plane angular movements of the pelvis and thorax were assessed . The same data were obtained from 30 healthy subjects . No differences were found in the recovery of spatiotemporal parameters or in angular movements of the pelvis and thorax following the computer-navigated MIS anterior approach or the conventional posterolateral approach . Although gait improved after surgery , small differences in several spatiotemporal parameters and angular movements of the trunk remained at 6 months postoperatively between both patient groups and healthy subjects BACKGROUND Both Minimally Invasive surgery ( MIS ) and Computer-Assisted Surgery ( CAS ) are useful in Total Knee Arthroplasty ( TKA ) . Minimally invasive total knee arthroplasty was associated with decreased blood loss , shorter hospital stays , and increased range of motion .  Computer-assisted surgery in total knee arthroplasty was developed to improve the positioning of implants during surgery . OBJECTIVE To evaluate radiographic results relative to component position and limb alignment when using a navigation system compared with conventional technique in MIS-TKA . MATERIAL AND METHOD A prospect i ve control study was performed in 180 patients who underwent total knee arthroplasty by one surgeon . All patients were r and omly divided into two groups , Conventional and Navigation TKA .  Intra- , post-operative data , and postoperative limb alignment were recorded for comparison in both groups . RESULTS The postoperative mechanical axis was within 3 degrees of neutral mechanical alignment in 94 % of the navigation group and 87 % in conventional group ( p = 0.13 ) . Registration time of navigation group is 13.58 minutes . No statistical significant difference was found in tourniquet time and postoperative blood loss in both groups . CONCLUSION The use of navigation in total knee arthroplasty increases accuracy in limb and implants alignment , and does not increase complications and surgical times Background A combination of two emerging technologies , computer-assisted navigation and minimally invasive surgery , in total knee arthroplasty has gained increasing interests from orthopedic surgeons around the world . To date , there has never been any midterm study for clinical and radiographic outcomes from using an electromagnetic computer-assisted navigation system . In this study , we aim ed to systematic ally compare clinical and radiographic outcomes of minimally invasive surgery in total knee arthroplasty ( MIS-TKA ) performed with and without electromagnetic computer-assisted navigation at immediate and midterm follow-ups . Methods A total of 151 patients ( 160 knees ) who underwent MIS-TKA were r and omized to be operated with electromagnetic computer-assisted navigation ( group I : 75 patients , 80 knees ) or without the navigation ( group II : 76 patients , 80 knees ) . The clinical and radiographic outcomes of immediate , 6-week postoperative follow-up and average 6.1-year follow-up were compared . Results On immediate , 6-week postoperative follow-up , clinical and radiographic outcomes did not reveal any difference between the two groups except for the fact that the operative time was longer in the navigation group . On 6.1-year follow-up , a total of 58 patients ( 63 knees ) from group I and 58 patients ( 61 knees ) from group II were reevaluated . There were no significant differences in clinical and radiographic loosening and in complications between the two groups . Conclusion In this study , no significant differences of clinical and radiographic outcomes were found for immediate and midterm follow-ups of MIS-TKA performed with and without electromagnetic computer-assisted navigation except for the additional operating time in the navigation group Background There has been increasing interest in performing total hip arthroplasty ( THA ) with minimally invasive surgery ( MIS ) . This study was conducted to examine the effectiveness of MIS-THA using the new two-incision technique versus the one-incision technique . Methods A consecutive series of 113 patients who underwent MIS-THAs ( 63 one-incision cases , 50 two-incision cases ) were studied .  One-incision THA was performed with a posterolateral approach . For the two-incision , the first incision for cup insertion was made over the anterolateral side of the hip . Intermuscular dissection was performed between the gluteus medius and the tensor fascia lata . The second incision , for stem insertion , was made on the posterolateral side of the hip along the fiber of the gluteus maximus . Intermuscular dissection was made between the gluteus medius and the piriformis . Results Postoperative rehabilitation was significantly more rapid in the new two-incision group compared to the group with one incision . Postoperatively , the Harris Hip Score and the Western Ontario and the McMaster Universities Osteoarthritis Index score were significantly different between the two groups , especially the functional sections . Conclusions The findings of this study show that our new two-incision MIS-THA is an excellent surgical modality that allows early rehabilitation Background For total hip arthroplasty ( THA ) , minimally invasive surgery ( MIS ) uses a smaller incision and less muscle dissection than the classic approach ( CLASS ) , and may lead to faster rehabilitation . Questions / purpose sDoes minimally invasive hip arthroplasty result in superior clinical outcomes ? Patients and Methods In this double-blind r and omized controlled trial , 120 consecutive primary noncemented THAs in 120 patients were assigned to one of two groups ( MIS or CLASS ) . The r and omization sequence was stratified for two groups of surgeons , ie , those using a posterolateral approach ( PL-CLASS or PL-MIS ) and those using an anterolateral approach ( AL-CLASS or AL-MIS ) . Length of the incisions was 18 cm for the CLASS procedures . MIS incisions were extended at the skin level to 18 cm at the end of the procedure . The primary end point was the Harris hip score ( HHS ) at 6 weeks postoperatively . Patient-centered question naires were obtained preoperatively and after 6 weeks and 1 year . Results For the patients in the MIS group ( average 7.8 cm incision length ) , statistically significant increased mean HHSs were seen compared with the CLASS group at 6 weeks and 1 year . This difference was small and mainly caused by the favorable results of the PL-MIS . In the MIS group , surgical time was longer . A learning curve was observed based on operation time and complication rate . Although not statistically significant , the perioperative complication rate was rather high in the ( anterolateral ) MIS group . Conclusions The minimal invasive approach in THA did not show a clinical ly relevant superior outcome in the first postoperative year . Level of Evidence Level I , therapeutic study . See Guidelines for Authors for a complete description of levels of evidence UNLABELLED While others have reported short-term comparisons between various minimally invasive surgical ( MIS ) approaches to  total hip arthroplasty ( THA ) and their conventional analogues , longer-term data is lacking , as is information indicating whether MIS approaches to THA provide a biomechanically complete recovery . Furthermore , different MIS approaches have not been compared . Our approaches of interest were a one-incision modified Watson-Jones , and a two-incision approach . HYPOTHESES ( 1 ) There are significant differences in gait recovery patterns between the two surgical groups and ( 2 ) THA subjects have significant differences in function one year after surgery compared to control subjects . To test these hypotheses , THA c and i date s ( n=26 ) were r and omized to receive one of these MIS approaches and evaluated preoperatively , and postoperatively at 3 weeks , and at 3 , 6 and 12 months . Evaluations included three-dimensional gait analysis and 24-hour step-counts . The same data were obtained from 25 control subjects .  Recovery time-course was assessed using repeated measures ANOVA . T-tests were used to compare controls with the pooled group of THA subjects . We found no differences between the two THA surgical groups regarding the time-course of recovery ( p≥0.591 ) . Although recovery was statistically complete by 3 months postoperatively for all variables , there were significant differences from controls at 12 months . Most notably , the external hip adduction moment , which reflects hip abductor function , was more than one st and ard deviation below normal ( p<0.001 ) . THA subject inactivity could not explain the gait differences , since one year after surgery daily step counts were not significantly different from controls ( p=0.346 ) . More work is necessary to determine ways to improve biomechanical outcomes for today 's patients with high expectations for function and implant longevity Optimal orientation of the acetabular component of a  total hip prosthesis  is an important factor in determining the early and long-term result of a  total hip arthroplasty ( THA ) . Conventional positioning of the cup component is usually done using a free-h and method , or with the help of a mechanical acetabular alignment guide . However , these methods have proven to be inaccurate , and a great variation in orientation of the cup is found postoperatively . In this study , we wished to determine if the variability of the abduction angle of acetabular cups could be reduced with the use of computer navigation . The abduction angles of the acetabular components of three groups of 50 THAs were assessed . In the first group , a free-h and method was used to position the cup component . This group was operated in the period before we started using computer navigation for hip surgery . In the second group , CT-based computer navigation was used to plan and help position the cup . The third group consisted of 50 THA cases in which a free-h and method was used to position the cup , although these procedures were performed in the period after we had begun using the Computer Assisted Surgery ( CAS ) system . The variability in cup abduction angle was assessed in all three groups and compared . There was a significant reduction in variability in the CAS group compared to the first group . There was also a reduction in variability in the CAS group compared to the third group , although this was not statistically significant . It is concluded that the use of computer navigation helped the surgeon to place the cup component with less variability of the abduction angle , and , more importantly , we found that no cups were placed in the more extreme positions ( outliers ) Background Despite the growing evidence in the literature there is still a lack of consensus regarding the use of minimally invasive surgical technique ( MIS ) in total knee arthroplasty ( TKA ) . Methods A prospect i ve , r and omized , international multicentre trial including 69 patients was performed to compare computer-assisted TKA ( CAS-TKA ) using either mini-midvastus ( MIS group ) or st and ard medial parapatellar approach ( conventional group ) .  Patients from 3 centers ( Maastricht , Zwickau , Adelaide ) with end-stage osteoarthritis of the knee were r and omized to either an MIS group with dedicated instrumentation or a conventional group to receive cruciate retaining CAS-TKA without patella resurfacing .  The primary outcome was to compare post operative pain and range of motion ( ROM ) . The secondary outcome was to measure the duration of surgery , blood loss , chair rise test , quadriceps strength , anterior knee pain , Knee Society Score (KSS),WOMAC scores , mechanical leg axis and component alignment . Results Patients in the MIS group ( 3.97 ± 2.16 ) had significant more pain at 2 weeks than patients in the conventional group ( 2.77 ± 1.43 ) p = 0.003 . There was no significant difference in any of the other primary outcome parameters . Surgery time was significantly longer ( p < 0.001 ) and there were significantly higher blood loss ( p = 0.002 ) in the MIS group as compared to the conventional group . The difference of the mean mechanical leg alignment between the groups was not statistically significant ( –0.43 ° ( 95 % CI –1.50 – 0.64 ) ; p = 0.43).There was no significant difference of component alignment between the two surgical groups with respect to flexion/extension ( p = 0.269 ) , varus/valgus ( p = 0.653 ) or rotational alignment ( p = 0.485 ) of the femur component and varus valgus alignment ( p = 0.778 ) or posterior slope ( p = 0.164 ) of the tibial component . Conclusion There was no advantage of the MIS approach compared to a conventional approach CAS-TKA in any of the primary outcome measurements assessed , however the MIS approach was associated with longer surgical time and greater blood loss . MIS-TKA in combination with computer navigation is safe in terms of implant positioning . Trial registration number Clinical Trials.gov NCT02625311 8 December BACKGROUND Minimally invasive surgery ( MIS ) has perceived advantages in the early post-operative stage such as reduced blood loss , decreased pain , earlier return to function and earlier discharge . The aim of our study was to confirm that longer term clinical outcome of TKA is not compromised when MIS is combined with computer assisted surgery . METHODS Eighty patients matched for age , gender , pre-operative Knee Society Score ( KSS ) and mechanical axis were prospect ively studied . Forty patients underwent minimally invasive computer assisted total knee arthroplasty ( MICATKA ) and 40 patients underwent conventional computer assisted TKA ( CATKA ) .  Functional scores were determined at 6 weeks , 6 , 12 , 18 , and 24 months and 5 years post-surgery . Long-leg alignment views were obtained 3 months post-operatively . RESULTS KSSs in the short term were significantly better in the MICATKA group than in the CATKA group ( p<000.1 ) . Tourniquet-time was 58 min in the MICTKA group and 60 min in the CATKA group ( p=0.3 ) . Straight leg raise was achieved by day one in 93 % of the MICATKA group compared to 30 % of the CATKA group ( p<0.001 ) . Length of stay for the MICATKA group has a mean of 3.25 days and a mean of 6 days for the CATKA group ( p<0.001 ) . KSSs up to 2-years were significantly better in the MICTKA group ( p<0.001 ) . At 5-years there was no significant difference in KSSs ( p=0.46 ) in the MICATKA and CATKA groups . CONCLUSION We confirm that the use of navigation in minimally invasive TKA permits a number of early post-operative advantages and that longer-term functional outcome is not compromised with its usage . LEVEL OF EVIDENCE Level II Background and purpose There is still conflicting evidence about the true benefit of minimally invasive ( MI ) techniques in total hip replacement ( THR ) . The aim of this prospect i ve study was to evaluate the safeness of a MI approach during the learning curve of a single surgeon . Second , clinical and radiographic results among the  MI THR group were compared with the results using a st and ard transgluteal ( Bauer ) approach . Methods 86 primary unilateral total hip arthroplasties ( THAs ) through a MI , anterior ( Micro-hip ® ) approach were performed by a single senior surgeon ( ES ) , representing a consecutive series of patients after beginning with the MI technique . Cases were compared to a matched cohort of patients who were treated with a st and ard transgluteal ( Bauer ) approach .  Operation time , incision length , perioperative blood loss , haemoglobin level and blood transfusions were monitored . Complications were documented and followed up 1 year postoperatively . The Harris Hip Score ( HHS ) , range of motion , use of analgetics , the Trendelenburg sign , sensibility of the lateral femoral cutaneous nerve and the acetabular/femoral component placement as well as potential heterotopic ossifications were analysed in both the groups after 12 months postoperatively . Results 74 MI THR patients and 60 st and ard THR patients were available for the one year follow-up . Operative time was significantly longer in the MI group , reduction in the haemoglobin level during the first 24 h was significant and the length of skin incision was significantly shorter . No significant differences were found for HHS , range of motion , use of analgetics , the Trendelenburg sign , and the acetabular/femoral component placement , heterotopic ossifications and intra- and postoperative complications . Sensibility of the lateral femoral cutaneous nerve was affected in three patients in the MI group . Radiographic evaluation revealed no component migration , implant subsidence or radiolucency signs in both the groups . DicussionConsistent with recent meta- analysis we found reduced blood loss , similar clinical /radiographic outcome and similar complication rates compared to st and ard THA . Our study shows , that MI THR is a safe procedure during the learning curve of an experienced surgeon INTRODUCTION Thromboembolic events ( TEE ) are serious complications after total hip ( THA ) and knee arthroplasty ( TKA ) , with reported in-hospital incidences of about 0.5 - 1 % for venous thromboembolic events ( VTE ) and 0.2 % for myocardial infa rct ions ( MI ) and stroke . However , little data exist on in-hospital TEE when using a st and ardized fast-track protocol with early mobilization . MATERIAL S AND METHODS A large detailed cohort study in primary unilateral THA and TKAs on " early " ( in-hospital or after discharge but within 1week of surgery ) and 30-days TEEs , including prospect i ve recording of patient characteristics , complete follow-up through the Danish National Patient Register , and detailed evaluation on disposing factors and consequences of " early " TEEs through review of medical records . RESULTS In 13,775 procedures with a median LOS of 2days , 43 ( 0.32 % ; 95 % CI : 0.23 - 0.42 ) " early " and 90 ( 0.65 % ; 95 % CI : 0.53 - 0.80 ) 30-day TEEs were recorded . " Early " TEEs consisted of 9 ( 0.07 % ; 95 % CI : 0.04 - 0.13 ) MI , 10 ( 0.08 % 95 % CI : 0.04 - 0.13 ) strokes , 13 ( 0.09 % ; 95 % CI : 0.05 - 0.16 ) pulmonary embolisms and 11 ( 0.08 % ; 95 % CI : 0.04 - 0.15 ) deep venous thromboses . Most TEEs were in patients with irreversible dispositions ( e.g. previous TEE , high age and cardiac disease ) , but 5 of 9 MIs were associated with postoperative anemia . All in-hospital VTE ( n : 16 ) occurred while patients received recommended thromboprophylaxis . CONCLUSIONS Incidence of " early " TEEs after fast-track THA and THA is low , but MIs may be further reduced by improving perioperative treatment of anemia . Further research is needed regarding interventions for prevention of " early " TEE in disposed patients Background and purpose — Acute myocardial infa rct ion ( MI ) is a leading cause of mortality following total hip and knee arthroplasty ( THA/TKA ) . The reported 30-day incidence of MI varies from 0.3 % to 0.9 % . However , most data derive from administration and insurance data bases or large RCTs with potential confounding factors . We studied the incidence of and potential modifiable risk factors for postoperative MI in a large , multicenter optimized “ fast-track ” THA/TKA setting . Patients and methods — A prospect i ve cohort study was conducted on consecutive unselected elective primary unilateral THA and TKA  , using prospect i ve information on comorbidities and complete 90-day follow-up from the Danish National Patient Registry . Evaluation of discharge summaries and medical records was undertaken in cases of suspected MI . Logistic regression analyses were carried out for identification of preoperative risk factors . Results — Of 24,862 procedures with a median length of stay 2 ( IQR 2–3 ) days , 30- and 90-day incidence of MI was 31 ( 0.12 % ) and 48 ( 0.19 % ) . Preoperative risk factors for MI ≤30 days were age > 85 years ( OR 7.4 , 95 % CI 2.3–24 ) , insulin-dependent diabetes mellitus ( IDDM ) ( 3.6 , CI 1.1–12 ) , cardiovascular disease ( 2.4 , CI 1.1–5.0 ) and hypercholesterolemia ( 2.3 , CI 1.1–5.1 ) . Of 31 patients with MI ≤30 days 9 were treated with vasopressors for intraoperative hypotension and 27 had postoperative anemia . Interpretation — Fast-track THA and TKA had a low 30-day MI incidence . Focus on patients with age > 85 , IDDM , cardiovascular disease , and hypercholesterolemia may further reduce the 30-day incidence of MI . The role of postoperative anemia and intraoperative hypotension are other areas for further AIM Different surgical approaches are used in total hip arthroplasty . The present study confronted two surgical techniques , analysing functional recovery in terms of activities of daily living , and ambulation using gait analysis , after a st and ardized rehabilitation protocol . Our hypothesis was that the increased surgical damage could modify the gait pattern and functional recovery . METHODS Thirty patients were r and omly assigned to two homogeneous groups : Group A was treated with intermuscular minimally invasive surgery ( MIS ) ; Group B was treated with st and ard lateral transmuscular approach . Follow up was planned at 30 and 90 days . Instrumental evaluation using gait analysis and functional evaluation using vali date d scales were performed at follow up . RESULTS No differences could be found as for functional scales . At the first follow up , the MIS approach proved to be the most favourable : data showed a longer duration of the swing phase , an improved range of motion of the non-treated hip , a reduced adduction ( all P<0.005 ) and a correct timing of activation of the gluteus medium muscle on the treated side . At the second evaluation , gait analysis demonstrated some benefits of the intermuscular approach ( a better flexion of both hips , and a minor obliquity of the pelvis during the terminal stance ) , but also advantages in the transmuscular group ( better hip extension ) . CONCLUSION Gait pattern after THA seems to be strictly dependent on surgical access and on the extent and location of surgical damage . It appears important to consider these elements in order to correctly manage the rehabilitation treatment after surgery BACKGROUND The purpose of this study was to report minimum 2-year outcomes and complications for robotic-arm-assisted total hip arthroplasty ( THA )  . METHODS Data were prospect ively collected and retrospectively review ed between June 2011 and April 2014 . Inclusion criteria were primary robotic-arm-assisted THAs treating idiopathic osteoarthritis with ≥ 2-year follow-up .  Demographics , operating time , complications , 2-year outcome scores and satisfaction , and subsequent surgeries were recorded . RESULTS There were 181 cases eligible for inclusion , of which 162 ( 89.5 % ) had minimum 2-year follow-up . At the latest follow-up , the mean visual analogue scale was 0.7 , satisfaction was 9.3 , Harris hip score was 91.1 and forgotten joint score was 83.1 . Six ( 3.7 % ) intraoperative complications and six ( 3.7 % ) postoperative complications were reported . No leg length discrepancies ( LLDs ) or dislocations were reported . CONCLUSIONS Robotic-arm-assisted THA demonstrates favourable short-term outcomes and does not result in a higher complication rate compared to non-robotic THA as reported by the literature Abstract Introduction Up to now , no prospect i ve , r and omized comparisons between minimal invasive and computer-assisted total knee arthroplasty ( MICA-TKA ) , and minimal invasive technique ( MI-TKA ) has been documented to evaluate not only clinical , but also radiologic results of the MICA-TKA . This prospect i ve , r and omized study was performed to compare the short-term results of MICA-TKA with minimal invasive technique MI-TKA for 6-month follow-up . Patients and methods We reported the clinical and radiological results of 80 subjects who had cruciate-substituting , TKA-implanted primary total knee arthroplasties using either minimal invasive and computer-assisted technique ( 40 patients Group I ) or minimal invasive technique ( 40 patients , Group II ) .  Tourniquet time , length of skin incision , and total blood loss were compared . Knee society scores ( KSSs ) , knee society functional scores ( KSFSs ) , range of motion ( ROM ) , and radiographic results were assessed and reported preoperatively and at 6-month follow-up . Results The accuracy of the implantations in relation to the coronal mechanical axis in Group I was superior to that of Group II ( P < 0.05 ) . The femoral rotational profile revealed the prosthesis in Group I that was implanted with significantly less internal rotation than in Group II . The average blood loss in patients of Group I was significantly reduced as compared to patients of Group II . No significant difference was detected in terms of tourniquet time or length of skin incision . Clinical results , with regard to ROMs and KSSs , as well as KSFSs were equally good in both the groups . Conclusions Better alignment and similarity of good clinical results at short-term follow-up may provide subjects who receive MICA-TKA with long-term endurance of their implants . Further studies on longer-term outcomes and functional improvements are required to vali date these possibilities BACKGROUND Minimally invasive prosthetic hip surgery ( MIS ) attempts to minimise the extent of the operation . The aim of the study was to describe minimally invasive hip surgery and to present early clinical experience of the authors . MATERIAL AND METHODS 41 minimally invasive hip replacements through a posterior approach were carried out at the Orthopaedic Department of the Postgraduate Medical Education Centre in Otwock between 2004 and 2006 . 29 of those patients were included into the study , of whom 23 presented for follow-up . A control group consisted of 29 r and omly selected patients operated on using the classical method . Patients qualified for MIS had a BMI below 30 and a structurally normal hip joint with a good range of motion .  RESULTS Early results were subjected to a statistical analysis of 20 parameters . CONCLUSION 1 . The analysis showed that statistically significant baseline differences between MIS and traditionally treated patients included only BMI scores , structure of the hip joint and range of motion . 2 . Implantation of a hip endoprosthesis in a MIS procedure does not differ from the traditional operation utilising a posterior access except for skin incision length In this prospect i ve study we compared clinical and radiological results and rehabilitation progress of 64 patients who underwent total hip arthroplasty using the st and ard lateral approach with 64 patients operated with a minimal-invasive ( MIS ) posterior approach .  The outcome of our study did not show any significant differences with regard to patient 's safety such as complication rate and radiological assessment of the cup position . There was no difference in the duration of surgery , blood loss , hospital stay and postoperative leg length discrepancy . Rehabilitation milestones were achieved earlier by MIS patients and three and six months postoperatively , the Harris Hip Score of the MIS group was significantly higher Background Minimally invasive surgery ( MIS ) can lead to early recovery , but its postoperative effect is short after total hip arthroplasty for osteoarthritis . Because bipolar hemiarthroplasty ( BHA ) for femoral neck fractures is preferred for elderly patients , early functional recovery may prevent the rapid progression of disuse atrophy , and an MIS surgical approach may improve subsequent hip joint function . Methods MIS-BHA was performed using the direct anterior approach , without muscle or tendon detachment . A total of 83 patients who underwent BHA from April 2007 to February 2009 were assigned to MIS-BHA or conventional BHA . Selection of patients for MIS-BHA was not r and omized . Hip joint function was evaluated with the Hospital for Special Surgery ( HSS ) system at 1 month and 1 year after surgery . Results There were no significant differences in age , sex , height , weight , body mass index , time from admission to surgery , or preinjury HSS scores between two groups . HSS scores were higher with MIS-BHA ( 24.2 vs. 20.2 ; P = 0.01 ) at 1 month but were similar 1 year after surgery ( 29.9 vs. 27.2 ; P = 0.10 ) . Conclusions The effectiveness of MIS-BHA for femoral neck fracture is limited to the early postoperative period . Therefore , MIS-BHA does not appear to be appropriate for treatment of femoral neck fractures Study Design : A prospect i ve r and omized study was conducted . Objective : The purpose of this study was to assess the radiographic outcomes of one-level minimally invasive transforaminal lumbar interbody fusion ( MI-TLIF ) with unilateral pedicle screw instrumentation for degenerative lumbar spine disease . Summary of Background Data : MI-TLIF has become an increasingly popular method of lumbar arthrodesis . Recent technological advances in spinal instrumentation have culminated in the development of MI-TLIF with unilateral pedicle screw fixation . However , there are few published studies on radiographic outcomes of the MI-TLIF with unilateral pedicle screw fixation . Methods : A total of 65 patients with one-level degenerative lumbar spine disease were enrolled in this study . Patients were r and omized into the unilateral or bilateral fixation group based on a computer-generated number list . Thirty-one patients ( 17 men and 14 women ; average age , 57.3 y ) were r and omized to the unilateral group ( group A ) and 34 patients ( 16 men and 18 women ; average age , 58.9 y ) to the bilateral group ( group B ) . All patients underwent minimally invasive decompression , interbody fusion , and pedicle screw fixation with the assistance of microscopic tubular retractor system ( METRx-MD ) and Sextant system . All patients were asked to follow-up at 3 , 6 , and thereafter once every 6 months after surgery . The visual analog scale ( VAS ) , Oswestry disability index ( ODI ) , and modified Prolo ( mProlo ) scores were obtained for all patients 24 hours before the operation and at each follow-up visit . The whole lumbar lordosis ( WL ) , the segmental lordosis ( SL ) , fusion level disk space angle , lumbar scoliosis angle , and segmental scoliosis angle were determined before and after surgery on st and ard x-rays . The disk height index ( DI ) and the lumber curvature index ( LI ) were also evaluated . Results : The mean follow-up was 26.6 months , with a range of 18–36 months . All patients showed evidence of fusion at 12 months postoperatively . Statistically , there was no significant difference between the 2 groups in terms of demographic data . The average postoperative VAS , ODI , and mProlo scores improved significantly in each group . No significant differences were found between the 2 groups in relation to VAS , ODI , and mProlo scores at each follow-up time point . There were no significant differences between the 2 groups in relation to WL , SL , disk space angle , lumbar scoliosis angle , segmental scoliosis angle , DI , and LI . There was also no difference between postoperative different follow-up visits in terms of these radiographic parameters in both groups . There was a positive linear correlation between the LI and WL in both groups . Conclusions : One-level unilateral pedicle screw instrumented MI-TLIF provided similar radiologic and clinical outcomes to bilateral pedicle screw instrumented MI-TLIF . This study showed that MIS-TLIF with unilateral pedicle screw fixation would be sufficient in the management of preoperatively stable patients with lumbar degenerative disease A total of 208 patients were enrolled in a multicenter , prospect i ve r and omized , institutional review board-approved study that compared preoperative surgical plan to postoperative 2-dimensional radiographic alignment measured by a blinded review er for  primary total knee arthroplasty ( TKA ) implanted using computer-assisted surgery ( CAS ) compared with conventional TKA instrumentation . The results demonstrated a statistically significant improvement in the coronal tibial component alignment ( P < .03 ) and failed to demonstrate a statistically significant improvement in the mechanical axis , femoral coronal/sagittal , and tibial sagittal alignment . Knee Society Score knee and function scores and 6-minute walk test were equivalent between the 2 treatment groups at all postoperative intervals . There was a statistically significant increase in the skin-skin time ( P < .0001 ) and the time until first bone cut ( P < .0001 ) for the CAS knees compared with those implanted with conventional instrumentation . The use of CAS in this r and omized clinical trial conducted at high-volume centers did not offer a clinical ly meaningful improvement in postoperative alignment , clinical , functional , or safety outcomes compared with conventional TKA Introduction : Minimally invasive surgery represents one of the most recent techniques to have emerged within THA . In conventional THA , the incision typically measures 15–20 cm . Minimal invasive approach defined as less invasive to the skin , muscles , or bone may reduce complications and improve recovery time . A number of different approaches and methods have been described in literature . Purpose : This is a prospect i ve study describing the technique and early results of the modified antero-lateral minimal invasive ( ALMI ) approach and comparing our results to the results of other investigators interested in minimal invasive THA . Material s and methods : Seventy-five consecutive primary total hip arthroplasties ( cemented and cementless ) were done through a modified ALMI approach ( 6–8 cm ) , in which we kept the hip abductors intact . Neither special instruments nor specially design ed prostheses were needed . Minimum follow-up was 12 months . Results : The mean Harris hip score for patients after 12-month follow-up was 90 while the mean Merle d’Abugine mean score was 16.5 . Both scores reached almost the maximum values within 3 months after surgery . The cup abduction angle for 70 % patients was between 35 ° and 45 ° . No femoral stem mal-alignment was recorded . The mean operative time of cemented prosthesis was 65 min while that of the cementless prosthesis was 55 min . No wound complications or dislocations were recorded . All the patients were allowed to weight bear in the second post-operative day and involved in an early rehabilitation program . Conclusion : ALMI hip approach with sparing of hip abductors is safe and gives excellent orientation for positioning of prosthesis components . It also allows early and smooth post-operative rehabilitation with fast recovery of the patient in terms of weight bearing Computer-assisted surgery in knee arthroplasty is gaining popularity ; however , the result ing outcome improvement is controversial . A double-blinded trial was performed with subjects r and omized to undergo surgery with either computer-assisted or nonassisted instruments .  Postoperatively , limb and implant alignment and rotation were assessed using both full-length radiographs and computed tomography in addition to clinical scores . One hundred twenty patients ( 141 knees ) were r and omized . No differences in Western Ontario MacMaster Osteoarthritis Score , Short Form-36 , or flexion were seen . More varus limb alignment was seen in the computer-assisted group ( 1.9 ° ) vs the nonassisted group ( 0.9 ° , P = .04 ) with no improvement in alignment precision . Rotational alignment of the components did not differ between groups . Computer-assisted surgery appeared to have minimal effect on knee implant arthroplasty with no improvement in limb alignment or early functional outcome
Strong evidence was found for a decrease in operative time and intraoperative blood loss for MIS THA , with no difference in complication rates and risk for acetabular outliers .
Strong evidence exists that there is no difference in physical functioning , measured either by question naires or by gait analysis .
Moderate evidence was found for a shorter length of hospital stay after MIS THA .
Conflicting evidence was found for a positive effect of MIS THA on pain in the early postoperative period , but that effect diminished after three months postoperatively .
Strong evidence was found for an increase in operative time for CAS THA , and limited evidence was found for a decrease in intraoperative blood loss .
Furthermore , strong evidence was found for no difference in complication rates , as well as for a significantly lower risk for acetabular outliers .
Conclusions The results indicate that MIS THA is a safe surgical procedure , without increases in operative time , blood loss , operative complication rates and component malposition rates .
However , the beneficial effect of MIS THA on functional recovery has to be proven .
The results also indicate that CAS THA , though result ing in an increase in operative time , may have a positive effect on operative blood loss and operative complication rates .
More importantly , the use of CAS results in better positioning of acetabular component of the prosthesis
Background Both minimally invasive surgery ( MIS ) and computer-assisted surgery ( CAS ) for total hip arthroplasty ( THA ) have gained popularity in recent years .
We conducted a qualitative and systematic review to assess the effectiveness of MIS , CAS and computer-assisted MIS for THA .