Mini-midvastus versus medial parapatellar approach in TKA: muscle damage and inflammation markers. Mini-midvastus versus mini-medial parapatellar approach for minimally invasive total knee arthroplasty: outcomes pendulum is at equilibrium. Comparison of the mini-midvastus with the mini-medial parapatellar approach in primary TKA. Mini-midvastus vs standard medial parapatellar approach: a prospective, randomized, double-blinded study in patients undergoing bilateral total knee arthroplasty. Mini-subvastus versus medial parapatellar approach for total knee arthroplasty: a prospective randomized controlled study A comparison of subvastus and midvastus approaches in minimally invasive total knee arthroplasty. Comparison of Early Postoperative Rehabilitation Outcome following Total Knee Arthroplasty Using Different Surgical Approaches and Instrumentation Patellar Tracking and Anterior Knee Pain are Similar After Medial Parapatellar and Midvastus Approaches in Minimally Invasive TKA A midvastus muscle-splitting approach for total knee arthroplasty. Quadriceps-sparing, minimal-incision total knee arthroplasty: a comparative study. Subvastus versus medial parapatellar approach in total knee arthroplasty Midvastus approach in total knee arthroplasty: a randomized, double-blinded study on early rehabilitation The John Insall Award: No Benefit of Minimally Invasive TKA on Gait and Strength Outcomes: A Randomized Controlled Trial Computer-assisted total knee arthroplasty using mini midvastus or medial parapatellar approach technique [Functional Comparison of the Outcome after Midvastus and Medial Parapatellar Surgical Approach in Total Knee Arthroplasty]. Better quadriceps recovery after minimally invasive total knee arthroplasty Differences between midvastus and subvastus TKA surgical approaches in the tasks of sitting and standing. Functional and radiological outcome after total knee replacement performed with mini-midvastus or conventional arthrotomy: controlled randomised trial Comparison of two minimally invasive implantation instrument-sets for total knee arthroplasty The effect of surgical approaches and tourniquet application on patellofemoral tracking in total knee arthroplasty. Comparison of Mini-Midvastus and Conventional Total Knee Arthroplasty with Clinical and Radiographic Evaluation: A Prospective Randomized Clinical Trial with 5-Year Follow-up. Approach to Total Knee Replacement: A Randomized Double Blind Study between Medial Parapatellar and Midvastus Approach in the Early Postoperative Period in Asian Population Early results of subvastus versus medial parapatellar approach in primary total knee arthroplasty The medial trivector approach in total knee arthroplasty. Quadriceps-sparing versus Mini-subvastus Approach in Total Knee Arthroplasty Comparison of quadriceps-sparing minimally invasive and medial parapatellar total knee arthroplasty: a 2-year follow-up study. Lateral subvastus approach with osteotomy of the tibial tubercle for total knee replacement: a two-year prospective, randomised, blinded controlled trial. Short Term Recovery of Function following Total Knee Arthroplasty: A Randomised Study of the Medial Parapatellar and Midvastus Approaches Factors affecting wound ooze in total knee replacement. Simultaneous Bilateral MIS-TKA Results in Faster Functional Recovery Sub-vastus approach is more effective than a medial parapatellar approach in primary total knee arthroplasty: a randomized controlled trial. Faster recovery after minimally invasive surgery in total knee arthroplasty Comparison of the subvastus and paramedian surgical approaches in bilateral knee arthroplasty. Mini-subvastus versus a Standard Approach in Total Knee Arthroplasty: A Prospective, Randomized, Controlled Study Comparison of the early results of minimally invasive vs standard approaches to total knee arthroplasty: a prospective, randomized study. Minimally invasive Oxford medial unicompartmental knee arthroplasty. A note of caution! Patellar eversion does not adversely affect quadriceps recovery following total knee arthroplasty. Total knee replacement performed with either a mini-midvastus or a standard approach: a prospective randomised clinical and radiological trial. Pain management after total knee arthroplasty using a multimodal approach. Patient-matched instruments versus standard instrumentation in total knee arthroplasty: a prospective randomized study
The purpose of this prospect i ve study was to analyze the biochemical markers of muscle damage and inflammation in patients treated with the mini-midvastus approach or the medial parapatellar approach for total knee arthroplasty . Of 60 patients who underwent unilateral total knee arthroplasty , 30 were treated with the mini-midvastus approach ( MMV group ) and 30 were treated with the  medial parapatellar approach ( MPP group ) . Serum creatine kinase , myoglobin , lactate dehydrogenase , glutamic oxaloacetic transaminase , C-reactive protein , interleukin-6 , and interleukin-1β levels were measured preoperatively , immediately postoperatively ( except for C-reactive protein level ) , and on postoperative days 1 , 2 , and 3 . Student 's t test , Pearson 's chi-square test , and Fisher 's exact test were used to compare the outcomes between the 2 groups . Compared with the MPP group , a significant increase in serum creatine kinase level existed in the MMV group on postoperative days 2 ( P=.08 ) and 3 ( P=.09 ) and cumulatively ( P=.02 ) . However , significantly elevated C-reactive protein and interleukin-6 levels existed in the MPP group . According to the serum creatine kinase levels , the mini-midvastus approach has no superiority over the medial parapatellar approach in terms of sparing muscle and may cause more muscle damage . Further study is warranted to determine the correlation between biochemical markers and functional deficits Comparisons between mini-midvastus ( mMV ) and mini-medial parapatellar approach ( mMPP ) for total knee arthroplasty ( TKA ) have reported variable results . We compared two approaches with minimum two year follow up . Forty consecutive patients who underwent staged bilateral TKA were prospect ively r and omized for mMPP approach in one knee and mMV approach in the other . Clinical parameters ( muscle strength , pain , ROM , Knee Society Score ) and surgic.l parameters ( duration of surgery , blood loss , lateral releases ) were assessed at 2 , 6 , 12 weeks and 6 , 12 , 24 months postoperatively . Clinical outcomes revealed inconsistent pattern of differences at various intervals . Surgical outcomes were not different . There were no major differences in outcomes between the two approaches . We recommend someone use surgical approach with which they are most familiar A prospect i ve r and omized study was performed to compare the clinical and radiological results of primary total knee arthroplasties ( TKAs ) using a mini-midvastus approach or a mini-medial parapatellar approach in 134 patients . The mini-midvastus approach was used on 68 patients ( group A ) and the mini-medial parapatellar approach on 66 patients ( group B ) . All knees were implanted with the same posterior-stabilized prosthesis by the same surgeon ( T.-S.T. ) with the same set of downsized instruments . Mean follow-up in both groups was 30.5 months ( range , 24 - 48 months ) . Patients in group A achieved an active straight-leg raise and 90 ° of flexion significantly earlier ( P=.017 and P=.025 , respectively ) . However , no significant difference was detected between the groups with respect to range of movement and Knee Society scores at all the postoperative visits and at final follow-up ( all , P>.05 ) . In contrast , the tourniquet time was significantly longer in group A ( P=.015 ) , with a higher incidence of medialized tibial component ( P=.031 ) . We believe that the early clinical results are similar between the mini-midvastus and mini-medial parapatellar approach . The mini-medial parapatellar approach is easier to initially apply and provides better visualization for TKA The purpose of this study was to determine whether the mini-midvastus approach to total knee arthroplasty ( TKA ) results in differences in quadriceps muscle strength as well as previously cited advantages in a double blind prospect i ve r and omized trial . Twenty-seven patients ( 54 TKAs ) scheduled for bilateral TKA were r and omized to undergo mini-midvastus approach on one knee and st and ard approach on the other . Incision lengths were the same . Postoperative strength was determined by isokinetic and isometric peak torque testing . Range of motion , pain Visual analog scale , side-preference , and gait analysis were assessed preoperatively and postoperatively . The only significant difference in strength testing was increased isokinetic and isometric extension torque at 3 weeks postoperatively for the mini-midvastus approach . No differences between the mini-midvastus and st and ard approach were observed for stride length , stance time , pain Visual analog scale , or knee range of motion . The mini-midvastus approach has limited benefit compared to the st and ard approach for TKA Purpose Whether minimally invasive total knee arthroplasty ( MIS-TKA ) could offer better and faster recovery without the deviation of post-operative prosthesis position and limb alignment is still controversial . This prospect i ve and r and omized study was conducted to compare the clinical and radiological outcomes between patients who underwent the mini-subvastus approach of MIS-TKA and those who underwent the medial parapatellar approach of traditional TKA .  Methods Fifty patients , including 50 knees , who required TKA due to osteoarthritis were r and omized to the mini-subvastus group ( group I ) or the medial parapatellar group ( group II ) . All patients accepted the same method of anaesthesia , equal support therapy and identical rehabilitation exercise after surgery . The evaluation system included operation time , tourniquet time , blood loss , skin incision length in flexion , straight leg raising time , the time of lower limb muscle strength up to grade 4 , the time of walking with aid or without aid , the time of walking up and down the stairs , the active flexion angle , range of movement ( ROM ) , the Knee Society Scores ( KSS ) , visual analogue score for pain ( VAS ) , hospital stays and radiographic outcomes . Results The mini-subvastus approach offered smaller skin incision length in flexion , but at the cost of operation time ( P < 0.001 ) . No significant difference was found in tourniquet time and blood loss . The patients in group I could achieve straight leg raising , the lower limb muscle strength up to grade 4 , walking with or without aid , and walking up and down the stairs earlier ( P < 0.001 ) . The active flexion angle , ROM , VAS and KSS in group I were superior to those in group II until six months post-operatively ( P < 0.001 ) , but the differences was not apparent at 12 months post-operatively . More importantly , there was no significant difference between the two groups on radiological outcomes ( P > 0.05 ) . Conclusions The mini-subvastus approach could offer faster recovery , less pain and shorter hospital stays without compromising the principles of proper prosthesis position and limb alignment compared with the medial parapatellar approach BACKGROUND The mini-subvastus and the mini-midvastus approaches are among the most common alternatives to the medial parapatellar approach for total knee arthroplasty . The purpose of this study was to compare the early clinical outcomes of these two approaches . METHODS In this prospect i ve , r and omized study of fifty-one patients who underwent bilateral total knee arthroplasty , the mini-subvastus approach was used in one knee and the mini-midvastus approach , in the contralateral knee . There were forty-two women and nine men who had a mean age of seventy years at the time of the index arthroplasties , and they were followed for two years postoperatively . Clinical outcome was assessed and compared with use of the Knee Society pain and function scores , the straight-leg-raising test , range of motion , and isokinetic strength testing . Operating time and blood loss for each approach were also compared . In addition , patients were surveyed concerning which knee they preferred . RESULTS Comparisons of postoperative Knee Society scores between both approaches at the time of the two-year follow-up did not yield a significant difference in outcome . Isokinetic strength testing at twelve weeks postoperatively revealed no significant differences in muscle strength , with a mean extensor peak torque-to-body weight ratio of 0.14 Nm/kg for both groups . No significant difference was found with respect to total blood loss , straight-leg-raising test , range of motion , or patient preference . There was no clinical ly relevant difference in operative times between the two approaches . CONCLUSIONS The minimally invasive subvastus and midvastus approaches for total knee arthroplasty were both associated with excellent short-term clinical results . Some surgeons believe that the subvastus approach completely avoids damage to the quadriceps mechanism and therefore would be associated with improved muscle function . This prospect i ve series did not identify a substantive difference between the two approaches . We believe that the decision between these surgical approaches should be based on surgeon preference and experience Purpose . To assess early postoperative rehabilitation outcome following  computer-assisted total knee arthroplasty ( TKA )  or st and ard instrumentation TKA using a medial parapatellar or subvastus approach . Methods . A prospect i ve controlled trial of 70 consecutive patients undergoing TKA with a low contact stress rotating platform prosthesis was conducted . Patients were r and omised to receive surgery with either computer navigation or st and ard instrumentation .  A medial parapatellar or subvastus approach was used according to the surgeons ' preference . Outcome measures included preoperative knee function , intra-operative factors , and postoperative rehabilitation . Results . Duration of surgery was significantly longer when using computer navigation ; however , operating time decreased with greater experience . A higher incidence and duration of early postoperative quadriceps dysfunction was associated with computer-assisted TKA through the medial parapatellar approach than through the subvastus approach or TKA performed with st and ard instrumentation . No patient who received surgery through the subvastus approach had a lag of more than 20 degrees , at 48 hours postoperatively , regardless of the instrumentation used . Conclusion . Computer-assisted TKA through a medial parapatellar approach was associated with delayed recovery of the quadriceps during early postoperative rehabilitation . This was due to the additional quadriceps dissection required to place the femoral tracking array . The subvastus approach is therefore recommended for computer-assisted TKA Background Since the medial parapatellar ( MPP ) approach in conventional TKA can cause patellar maltracking and anterior knee pain , some orthopaedic surgeons use the midvastus ( MV ) approach instead of the MPP approach to reduce patellar maltracking . Minimally invasive surgical ( MIS ) TKA has been developed to limit the damage to the surrounding muscle and reduce the necessity of patellar eversion during surgery . Thus , MIS TKA might be associated with proper patellar tracking and a low incidence of anterior knee pain . However , this presumption has not been confirmed . Questions / purpose sWe asked whether the incidence of patellar maltracking and anterior knee pain differed with the MV and MPP in association with MIS TKA . Methods We prospect ively followed 59 patients ( 60 knees ) treated with 60 primary cemented MIS TKAs from August 2009 to September 2010 . We r and omized the patients into two groups : 30 who had a limited MPP approach and 30 who had a mini-MV approach . We recorded the occurrence of anterior knee pain , patellar tilting , and subluxation . The minimum followup was 12 months ( mean , 18.03 months ; range , 12.00–25.08 months ) . Results We found no differences in anterior knee pain ( two of 30 , 7 % versus two of 30 , 7 % ) , mean patellar tilt ( 3.4º ± 2.9º versus 3.0 ± 2.3º ) , and mean patellar subluxation ( 1.5 ± 1.1 mm versus 1.1 ± 0.7 mm ) between the limited MPP and mini-MV groups , respectively . Conclusions MIS TKA using either the MPP or MV approach has a low incidence of patellar maltracking and anterior knee pain . Level of Evidence Level I , therapeutic study . See the Guidelines for Authors for a complete description of the levels of evidence This study presents a modification of the medial parapatellar surgical approach for total knee arthroplasty . This approach separates the vastus medialis muscle in the direction of its fibers beginning at the superior pole of the patella . One hundred eighteen consecutive total knee arthroplasty cases , performed by a single surgeon , were r and omized prospect ively to receive a medial parapatellar or midvastus muscle-splitting surgical approach . The frequency of lateral retinacular releases was recorded , patellar tilt and translation were measured , and quadriceps strength was tested . The midvastus muscle-splitting approach provided excellent exposure to all knees . Patellar stability and quadriceps strength were equivalent for the two approaches . It is concluded that the midvastus muscle-splitting approach is an efficacious alternative to the medial parapatellar approach for primary total knee arthroplasties Our study was conducted to compare radiographic alignments and functional outcomes with 2 approaches to minimal-incision total knee arthroplasty ( TKA ) : the minimal-incision medial parapatellar ( MP ) approach and the quadriceps-sparing ( QS ) approach with side-cutting instruments . Sixty patients ( 80 knees ) with primary osteoarthritis were r and omly assigned to receive MP or QS TKA .  Postoperative alignment of the femoral component was significantly less valgus , and postoperative alignment of the tibial component was significantly more varus with the QS approach than with the MP approach . One tibial outlier and 3 femoral outliers were observed with QS TKA . The overall postoperative hip-knee-ankle axis was more varus , and surgical time was longer with QS TKA .  Short-term isokinetic peak muscle torque , postoperative pain , and functional outcomes did not differ between the approaches Abstract . The subvastus approach for total knee replacement was compared with the st and ard medial parapatellar approach in terms of postoperative knee scores and quadriceps strength . Two groups of patients with similar characteristics were formed : the first group consisted of 12 knees of 9 patients who were implanted via the medial parapatellar approach , and for the second group the subvastus approach was used in 10 knees of 10 patients . The groups ' knee scores and quadriceps strength were compared preoperatively and postoperatively at week 6 , months 3 and 6 . The knee scores improved similarly in both groups , but the change was more pronounced in the subvastus group . Quadriceps strength was greater in the subvastus group at postoperative week 6 , but there was no significant difference between the groups in months 3 and 6 . It was concluded that although the subvastus approach offers greater quadriceps strength in the early postoperative period , it has no significant advantage in this aspect over the medial parapatellar approach The medial parapatellar approach has become the st and ard technique in total knee arthroplasty ( TKA ) . However , recent studies have reported superior results regarding functional recovery when using the midvastus approach . It was the aim of this study to evaluate the early functional outcome of both surgical techniques . In a prospect i ve , double-blinded , r and omized study , 50 patients for TKA were consecutively operated on either by the medial parapatellar or the midvastus approach . Exclusion criteria were defined as previous open knee surgery and leg deformity of more than 10 ° varus or valgus . TKA was performed in all patients by one surgeon using the same type of implants in both groups . Pain scores ( VAS ) were documented and follow-up data including quadriceps strength and proprioception were obtained 3 weeks and 6 weeks postoperatively . Both groups were comparable in preoperative demographic data . Postoperatively , patients in the midvastus group demonstrated significantly lower pain in rest ( VAS : mean 2.25 vs. 3.03 ) and under movement ( VAS : mean 2.92 vs. 3.13 ) . Further , they showed superior isometric quadriceps strength at 3 weeks ( 41.4 vs. 27.6 Nm ) and 6 weeks ( 47.6 vs. 35.5 Nm ) . Moreover , this group showed a superior postoperative proprioception , while the range of motion was similar in both groups . The midvastus approach offers advantages over the st and ard parapatellar arthrotomy , in the early rehabilitation period . No adverse effects were observed associated with this approach . Therefore , the midvastus approach should be considered as a valuable alternative in TKA Background While some clinical reports suggest minimally invasive surgical ( MIS ) techniques improve recovery and reduce pain in the first months after TKA , it is unclear whether it improves gait and thigh muscle strength . Questions / Purpose sWe hypothesized TKA performed through a mini-subvastus approach would improve subjective and objective and subjective function compared to a st and ard medial parapatellar approach 2 months after surgery . Methods We r and omized 40 patients into two groups using either the mini-subvastus approach or st and ard medial parapatellar approach .  Patients were evaluated preoperatively and 2 months after surgery . We assessed subjective functional outcome and quality of life ( QOL ) using routine question naires ( SF-12 , Knee Society Score [ KSS ] , Knee Injury and Osteoarthritis Outcome Score [ KOOS ] , UCLA activity , patient milestone diary of activities ) . We determined isometric strength of the thigh muscles and assessed gait with a three-dimensional ( 3-D ) analysis during level walking and stair climbing . Results We observed improvements from preoperatively to 2 months postoperatively in functional scores , QOL , and knee kinematic and kinetic gait parameters during level and stair walking . Isometric quadriceps strength increased in both groups , although remaining lower when compared to sound limbs . We found no differences between the groups in KSS , SF-12 , KOOS , UCLA activity , patient milestone diary of activities , isometric quadriceps strength , or 3-D gait parameters , except a marginally higher speed of stair ascent in the MIS group . Conclusions Our observations suggest an MIS approach does not confer a substantial advantage in early function after TKA.Level of Evidence Level I , therapeutic study . See Instructions to Authors for a complete description of levels of evidence 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 There are various approaches for total knee arthroplasty ( TKA ) . On the basis of an analysis of the clinical results , it has been demonstrated that the midvastus approach ( MV ) is advantageous in the early postoperative period compared to the medial parapatellar surgical approach ( MPP ) . The aim of this investigation was therefore to investigate whether the clinical advantage of MV is reflected in the functional outcome . This single blinded , prospect i ve , r and omised study was based on a power analysis . Selected r and omised patients ( MPP = 10 , MV = 11 ) were examined using an instrumental gait analysis system ( VICON ) preoperatively , and 5 weeks ( 5 W ) and 6 months ( 6 M ) after implantation . The results were compared to a healthy control group ( CG = 53 ) . Besides clinical parameters , the primary objective of this study was to measure objective gait parameters ; the secondary objective was to record self- assessment ( Knee Society score , WOMAC ) . In both treatment groups , the measurements improved during the investigation period , although most parameters did not reach the CG levels . MV gave better values for the kinetic parameters sagittal knee moment ( 5 W ) and knee power ( 5 W , 6 M ) , as well as self- assessment ( WOMAC , 6 M ) . Other clinical parameters were similar in the two groups . In summary , in the early postoperative period , MV led to advantages in function and in subjective behaviour in daily life . From the biomechanical point of view , the MV approach is preferable Purpose The proponents of  minimally invasive total knee arthroplasty ( TKA )  have reported better functional recovery than conventional TKA . In most of the previous studies , the results were shown with the relatively subjective methods . We investigated the objective results with a dynamometry in this prospect i ve r and omized study . It was hypothesized that minimally invasive TKA would have a better and earlier recovery of quadriceps force in terms of the objective numeric data . Methods Sixty-six TKAs were prospect ively r and omized into two groups . Thirty-three knees underwent minimally invasive TKA using mini-midvastus approach and 33 knees underwent conventional TKA using medial parapatellar approach .  The quadriceps force was assessed using a dynamometer . The data were collected preoperatively and at postoperative 6 weeks , 3 months , 6 months and 1 year consecutively . Results The mean of quadriceps force in minimally invasive TKA group at postoperative 6 weeks was greater than conventional TKA after removing the covariate ( preoperative quadriceps force ) with analysis of covariance ( P = 0.002 ) , but thereafter , the difference was not significant till 1 year . Meanwhile , with repeated measures analysis of variance , conventional TKA group had greater quadriceps recovery than minimally invasive TKA group during postoperative 6 weeks to 3 months ( P = 0.035 ) . The proportion of patients unable to recover the quadriceps force to their preoperative levels by 1 year postoperatively was similar in two groups . Conclusion Minimally invasive TKA has benefit in quadriceps recovery at earlier rehabilitation period although catch-up recovery in conventional TKA was accelerated from the postoperative 6 weeks to 3 months . It may support the concept of early return to full activity after minimally invasive TKA , and patients might get back early to normal life . Level of evidence Therapeutic study , Level The mini-midvastus ( MV ) approach to total knee arthroplasty ( TKA ) minimizes damage to the extensor mechanism ; however , the mini-subvastus ( SV ) approach is design ed to avoid such damage . Quadriceps weakness following TKA can have a significant impact on the activities of daily living , particularly st and -to-sit down ( STSD ) and sit-to-st and up ( STSU ) activities . Fifty-three subjects diagnosed with primary osteoarthritis and scheduled to undergo TKA were r and omized to receive an MV or SV surgical approach and were given identical postoperative orders . Compared with age-matched controls , the SV group had a quicker return of normal peak knee extension moment during STSU , whereas the MV group had a quicker return of normal movement patterns in hip , knee , and ankle parameters during STSD yet represented the higher functioning subjects as more MV subjects had difficulty completing the task as instructed . Considering both movements are required for daily living , neither surgical group was found to have a significant advantage over the other in functional outcome through 6 months post-TKA The results of minimally invasive techniques used for total knee replacement are controversial . Despite reported advantages such as faster recovery , there are some concerns regarding component positioning . We compared mini-midvastus versus medial parapatellar arthrotomy with respect to component position and functional results . We included 70 osteoarthritis total knee replacement patients in our study . Patients were r and omised for the approach . We recorded Knee Society scores before and after the surgery and radiological component position . Patients were followed up to 12 weeks after the surgery . We found that the mini-midvastus approach was associated with better Knee Society scores six weeks after surgery ; after 12 weeks the difference was not statistically significant . We found no difference related to the approach in radiological component position . The mini-midvastus approach is associated with faster recovery and reproduces the same accuracy in component positioning as the medial parapatellar approach . RésuméLes techniques de chirurgie mini-invasives sont controversées dans les prothèses totales du genou . En dépit d’une récupération plus rapide , il est nécessaire de bien observer la position des implants . Nous avons comparé un abord mini-midvastus versus à un abord parapatellaire médian sur les critères position des implants et sur les résultats fonctionnels . Matériel et méthode : 70 approches du genou avec remplacement total ont été étudiés . Les patients ont été r and omisés selon la voie d’abord . Le score de la Knee Society et l’étude radiologique ont permis l’évaluation de ces prothèses . Les patients ont été suivis 12 semaines après l’intervention chirurgicale . Résultats : nous avons trouvé que l’abord mini-midvastus était associé à un meilleur score fonctionnel 6 semaines après l’intervention . Après 12 semaines , la différence n’est pas statistiquement significative . Nous n’avons pas trouvé de différence en ce qui concerne la position des implants . En conclusion : l’abord mini-midvastus est associé à une récupération plus rapide et , permet de positionner les implants de façon aussi efficace que lors d’un abord parapatellaire médian Several choices of instrument systems are available for minimally invasive surgical approaches . There are reports that one alternative , the quadriceps sparing , side-cutting instrumentation , results in diminished implantation accuracy . A total of 108 patients were r and omized to undergo TKA either using side-cutting implant instrumentation ( Group A ) or anterior – posterior mini-incision instrumentation ( Group B ) . All TKAs were operated on with a minimal invasive , mini-midvastus surgical approach . 50 % of the TKAs were performed with computer-assistance in each cohort . The radiographic parameters , clinical outcomes and knee scores were evaluated preoperatively and 3 months postoperative . In Group B , we found significantly higher accuracy for the mechanical axis of the limb ( range ±3 ° : Group A 54 % versus Group B 89 % , p = < 0.001 ) , medial proximal tibial angle ( range ±3 ° : Group A 85 % versus Group B 98 % , p = < 0.027 ) and tibial slope ( range ±3 ° : Group A 59 % versus Group B 85 % , p = < 0.007 ) . The application of the navigation system could only significantly reduce outliers ( accuracy > 3 ° ) in Group B. Clinical outcomes and knee scores were similar in both groups and were not influenced by computer-assistance . Using the anterior – posterior , mini-incision instruments for minimally invasive TKA will lead to higher implantation accuracy when compared to the quadriceps sparing side-cutting instrumentation . The navigation technique could not compensate for shortcomings of the side-cutting instrumentation . The clinical relevance of this study is that the quadriceps sparing side-cutting instrumentation should not be used for TKA because of unacceptable reduced implantation accuracy The purpose of this study was to assess the influences of surgical approaches and tourniquet application on the lateral retinacular tension ( LRT ) .  Single- setting bilateral total knee arthroplasty was performed in 10 patients , and the medial parapatellar and midvastus approaches were r and omly performed on each knee using tourniquet application . The LRT was measured using the buckle transducer before and after each approach . Next , the tourniquet was deflated and the measurement was repeated . After the parapatellar approach , LRT was significantly decreased . Conversely , no significant change was seen after the midvastus approach with the tourniquet inflated . However , in the midvastus approach , LRT was significantly decreased after tourniquet deflation . We concluded that both the parapatellar and midvastus approaches influence patellar tracking and LRT BACKGROUND The main objective of this prospect i ve r and omized study was to compare the clinical and radiographic outcomes of the mini-midvastus ( MMV ) approach with the conventional approach for total knee arthroplasty at the 5-year follow-up . METHODS Ninety-seven patients ( 100 knees ) with osteoarthritis were assigned to the MMV  group or to a group receiving conventional total knee arthroplasty .  Intraoperative and postoperative clinical data were collected . At 6 weeks and at 1 , 2 , and 5 years postoperatively , the Knee Injury and Osteoarthritis Outcome Score ( KOOS ) , the Oxford Knee Score ( OKS ) , the Knee Society Score ( KSS ) , and the Short Form (SF)-12 were completed . Radiographs of the knee were made preoperatively and at 1 day and 1 and 5 years postoperatively . Computed tomography ( CT ) scans were performed 2 years postoperatively . RESULTS In the MMV group , the mean skin incision was 2.5 cm shorter ( p < 0.001 ) and the mean duration of the operation was 6 minutes longer than in the conventional total knee arthroplasty group ( p < 0.05 ) . Eight patients in the conventional group had a lateral parapatellar retinacular release compared with 1 in the MMV group ; the difference was significant ( p = 0.01 ) . Three intraoperative complications , including 2 small lateral femoral condylar fractures and 1 partial patellar tendon laceration , occurred in the MMV group . Seven patients in the MMV group had postoperative blisters ; all of them had a relatively large femoral component and 4 of them were large men . The radiographs and CT scans of the prostheses showed no significant differences between the MMV and conventional groups except for the posterior slope of the tibial component . In addition , no significance differences were detected between the groups with respect to the KOOS , OKS , KSS , and SF-12 scores determined at the 6-week and the 1 , 2 , and 5-year follow-up evaluations . CONCLUSIONS In the rehabilitation period and at the short and mid-term follow-up , no relevant clinical and radiographic differences were found between the MMV and the conventional approach for total knee arthroplasty , making the advantage of MMV total knee arthroplasty cosmetic . We discourage the use of the MMV approach in large male patients because of the increased number of intraoperative complications and skin blisters postoperatively . LEVEL OF EVIDENCE Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence & NA ; The purpose of this r and omized study was to compare clinical and surgical outcomes of total knee replacements ( TKRs ) in the early postoperative period using midvastus approach versus medial parapatellar approach in Asian population in a double blind manner . Forty‐two knees each were operated using midvastus approach and the medial parapatellar approach .  Clinical parameters that were evaluated included Knee Society score ( KSS ) ; knee pain using visual analogue scale ( VAS ) on day 1 , 1 week , and 1 month ; time required to straight leg raise ( SLR ) ; patellar tracking ; mean extensor lag at 1 week and 1 month ; and time of discharge from the hospital . Surgical parameters that were evaluated included tourniquet time , incidence of lateral retinacular release , estimated blood loss , and any complications during the surgery . KSS at 1 week and 1 month postoperatively were significantly higher in the midvastus group as compared with medial parapatellar group ; though similar at 3 months , 6 months , and 1 year . The patients in midvastus group required fewer number of lateral retinacular releases ; achieved SLR earlier ; had less mean extensor lag at 1 week ; had less mean VAS score at day 1 , 1 week , and 1 month ; and had shorter hospital stay . There was no significant difference in the mean tourniquet time and estimated blood loss . One patient had patellar maltracking in the medial parapatellar group as compared with none in midvastus group . Midvastus approach to TKR results in quicker functional recovery with early discharge and rehabilitation in the Asian population as compared with medial parapatellar approach Introduction To evaluate the clinical and radiographic results immediately after total knee arthroplasty , we compared the parapatellar and subvastus approach . Material s and methods Fifty-two patients with osteoarthritis were r and omly assigned to two groups . The measurement was based on clinical and radiographic features . Results There was a significant difference in passive range of motion . Patients in the subvastus approach group revealed a full knee extension and flexion of 90 ° significantly earlier than those in the parapatellar group . However , on the day of discharge , both groups were comparable . Radiological assessment revealed analogous results in both groups . Correction of varus or valgus deformity was required in 48 patients . Conclusion Regardless of the surgical approach , the anteroposterior tibial femoral angle improved significantly in both groups . Concerning pain , operation time , blood loss , blood substitution and complications , no major differences could be seen This study compares the clinical results of the medial trivector approach to the st and ard parapatellar approach in primary total knee arthroplasty . Ten patients undergoing simultaneous bilateral total knee arthroplasty were included in this study . Right and left knees were r and omized for a st and ard medial parapatellar arthrotomy or a medial trivector approach . Patients were assessed by the number of days to achieve straight leg raising and range of motion at discharge . In addition , knee scores were obtained at 6 weeks and 6 months with careful assessment of any pain or tenderness around the quadriceps mechanism . At 6 months , patients were tested on a KINCOM machine assessing their concentric and eccentric quadriceps strength . While there was no difference in total range of motion at the time of discharge , patients undergoing a medial trivector approach achieved independent straight-leg raising 2 days sooner than patients undergoing a st and ard medial parapatellar arthrotomy . No significant differences existed in knee scores , pain scores , or range of motion at 6 weeks or 6 months . KINCOM testing at 6 months revealed the knees undergoing trivector approach to be 15 % stronger in concentric contractions . No complications were encountered with the use of the medial trivector approach in these patients . Subjectively , patients reported less discomfort and more strength in the knees having undergone a medial trivector approach . The medial trivector approach may enhance postoperative recovery without adversely affecting the quadriceps function following total knee arthroplasty . The medial trivector approach to the knee does not weaken quadriceps muscle function or adversely affect clinical results of total knee arthroplasty In a prospect i ve r and omized double-blind study we compared the postoperative recovery and early results of two groups of 30 patients having total knee arthroplasty with minimally invasive techniques using either a mini-subvastus or a modified “ quadriceps-sparing ” approach .  All knees were implanted with the same posterior-stabilized prosthesis ( LPS-Flex , Zimmer , Warsaw , IN ) by the same surgeon with the same dedicated set of downsized instruments . Epidural anesthesia with the same postoperative analgesia and rehabilitation protocol was used in all patients . Evaluation was performed preoperatively , postoperatively in the first week , and at 1 and 3 months . In five cases in the “ quadriceps- sparing ” group , the incision was extended a few cm to facilitate exposure . Tourniquet time , estimated blood loss , and postoperative pain were similar in the two groups . Active straight leg raising was achieved half a day earlier , on average , in the mini-subvastus group ( 1.9 vs 1.4 days ) . Average maximum active flexion was similar in the two groups at each interval , and reached 117 ° and 119 ° at 3 months for the mini-subvastus and “ quadriceps-sparing ” group , respectively . We believe there was no difference between the mini- subvastus and “ quadriceps-sparing ” approach in relation to short term recovery or early results . Level of Evidence : Level I , therapeutic study . See Guidelines for Authors for a complete description of levels of evidence BACKGROUND / PURPOSE Quadriceps-sparing minimally invasive total knee arthroplasty ( TKA ) has been proposed to limit surgical dissection without compromising surgical outcome . We conducted a prospect i ve and r and omized study to compare the outcomes of patients who underwent quadriceps-sparing TKA  with the outcomes of those who underwent st and ard medial parapatellar TKA  , after a 2-year follow-up period . METHODS Eighty primary TKA procedures that were to be performed in 60 osteoarthritis patients were r and omly assigned to either a  quadriceps-sparing ( 40 knees ) or a  st and ard medial parapatellar ( 40 knees ) group . All surgeries were design ed to set the prosthesis with a femoral component alignment of 7 ° valgus and a tibial component alignment that was perpendicular to the tibial shaft . Surgical time and  tourniquet time were recorded . Outcome variables included knee function , as defined by a hospital for special surgery knee score ; quadriceps muscle strength , which was measured by an isokinetic dynamometer ; pain , as indicated on a visual analog scale ; prosthetic position , which was measured on plain radiograph ; and range of motion . RESULTS Patients who underwent the 38 quadriceps-sparing and 37 st and ard TKA  procedures completed the 2-year follow-up period without any infection or revision . The mean surgical time and tourniquet time were significantly longer in the quadriceps-sparing group . The mean peak quadriceps muscle strength , hamstring muscle strength , normalized muscle balance ( hamstring/quadriceps ratio ) , pain score , function score , and range of motion were comparable in both groups at 2 months and 2 years . In the quadriceps-sparing group , both the femoral and the tibial components were significantly more varus-deviated from the expected position . CONCLUSIONS Patients undergoing quadriceps-sparing and st and ard medial parapatellar TKA  had comparable outcomes for quadriceps muscle strength , hamstring-quadriceps balance , and knee function ; however , the quadriceps-sparing TKA was more time consuming surgically and result ed in a less accurate prosthesis position The lateral subvastus approach combined with an osteotomy of the tibial tubercle is a recognised , but rarely used approach for total knee replacement ( TKR ) . A total of 32 patients undergoing primary TKR was r and omised into two groups , in one of which the lateral subvastus approach combined with a tibial tubercle osteotomy and in the other the medial parapatellar approach were used . The patients were assessed radiologically and clinical ly using measurement of the range of movement , a visual analogue patient satisfaction score , the Western Ontario McMasters University Osteoarthritis Index and the American Knee Society score . Four patients were lost to the complete follow-up at two years . At two years there were no significant differences between the groups in any of the parameters for clinical outcome . In the lateral approach group there was one complication due to displacement of the tibial tubercle osteotomy and two osteotomies took more than six months to unite . In the medial approach group , one patient had a partial tear of the quadriceps . There was a significantly greater incidence of lateral patellar subluxation in the medial approach group ( 3 of 12 ) compared with the lateral approach group ( 0 of 16 ) ( p = 0.034 ) , but without any apparent clinical detriment . We conclude that the lateral approach with tibial tubercle osteotomy is a safe technique with an outcome comparable with that of the medial parapatellar approach for TKR , but the increased surgical time and its specific complications do not support its routine use . It would seem to be more appropriate to reserve this technique for patients in whom problems with patellar tracking are anticipated This pilot double blind r and omised controlled study aim ed to investigate whether the midvastus ( MV ) approach without patellar eversion in total knee arthroplasty ( TKA ) result ed in improved recovery of function compared to the medial parapatellar ( MP ) approach . Patients were r and omly allocated to either the MV approach or the MP approach . Achievements of inpatient mobility milestones were recorded . Knee kinematics , muscle strength , Timed Up and Go , WOMAC , and daily step count were assessed before and up to six months after surgery . Cohen 's effect size d was calculated to inform the sample size in future trials . Twenty-eight participants ( 16 males , 12 females ) participated .  Patient mobility milestones such as straight leg raise were achieved on average 1.3 days ( 95 % CI −3.4 to 0.7 , d = 0.63 ) earlier in the MV group . Knee extensor strength at 6 weeks after surgery was higher ( 95 % CI −0.38 to 0.61 , d = 0.73 ) in the MV group . No trends for differences between the groups were observed in knee kinematics , TUG , WOMAC , or step count . Our results suggest a short term advantage in the first 6 weeks after surgery of the MV approach over the MP approach , but a larger study is required to confirm these findings . This trial is registered with NCT056445 INTRODUCTION Wound ooze is common following total knee arthroplasty ( TKA ) and persistent wound infection is a risk factor for infection , and increased length and cost of hospitalisation . PATIENTS AND METHODS We undertook a prospect i ve study to assess the effect of tourniquet time , peri-articular local anaesthesia and surgical approach on wound oozing after TKA . RESULTS The medial parapatellar approach was used in 59 patients ( 77 % ) and subvastus in 18 patients ( 23 % ) .  Peri-articular local anaesthesia ( 0.25 % Bupivacaine with 1:1,000,000 adrenalin ) was used in 34 patients ( 44 % ) . The mean tourniquet time was 83 min ( range , 38 - 125 min ) . We found a significant association between cessation of oozing and peri-articular local anaesthesia ( P = 0.003 ) , length of the tourniquet time ( P = 0.03 ) and the subvastus approach ( P = 0.01 ) . CONCLUSIONS Peri-articular local anaesthesia , the subvastus approach and shorter tourniquet time were all associated with less wound oozing after total knee arthroplasty Abstract Simultaneous bilateral TKAs subject patients to more arduous and painful functional recovery and increased risk of hemodynamic complications than staged bilateral TKAs . Minimally invasive TKA ( MIS-TKA ) reportedly results in more rapid return of function by limiting the amount of soft tissue disruption . We asked whether bilateral MIS-TKA had advantages over conventional TKA with respect to faster functional recovery . We prospect ively r and omized 30 patients into an MIS group ( mini-medial parapatellar approach , 15 patients ) and a conventional group ( conventional medial parapatellar approach , 15 patients ) . We recorded range of motion and the time required to regain the ability to walk without assistance . Functional recovery in the MIS group was faster in rehabilitation milestones of walking without assistance and gain in range of motion .  Minimally invasive TKA may benefit patients undergoing simultaneous bilateral procedures with faster functional recovery . Level of Evidence : Level II , therapeutic study . See the Guidelines for Authors for a complete description of levels of evidence In a prospect i ve single-centre longitudinal r and omized controlled trial 116 patients were allocated to the sub-vastus approach , and 115 to the medial parapatellar approach .  At one week follow-up , compared to baseline , range of motion , Knee Society ( KS ) global , KS knee , and KS pain scores were significantly better in the sub-vastus group . At the one year follow-up , WOMAC global and pain scores , SF36 physical function and role-physical scores , and EuroQol utility and pain score were significantly better in the sub-vastus group . The ease of exposure in the sub-vastus approach was significantly worse . There was no significant difference in length of stay or analgesia intake . The sub-vastus approach to total knee arthroplasty was more effective than a medial parapatellar approach at both one week and one year post-operatively , but surgeons reported a less easy exposure in the sub-vastus group Purpose The aim of the study was to identify whether less soft tissue and muscle damage during surgery will allow faster recovery after total knee arthroplasty in comparison with the conventional technique . A limited medial parapatellar approach without tibial medial collateral ligament ( MCL ) desinsertion was compared with the conventional parapatellar approach . Methods Three hundred patients were r and omized either into the minimally invasive group ( MIS group ) or into the conventional group ( CON group ) . The evaluation was based on the Knee Society Score , range of motion , blood loss , period of hospitalization and postoperative hemoglobin level . Results The MIS group showed faster recovery with immediate postoperative full weight-bearing and shorter length of stay ( 5 vs 10 days ) . Comparable Knee Society Scores ( 87.5 vs 88 ) , function scores ( 90 ) and alignment ( 5.5 ° vs 5.2 ° ) between the CON and MIS group were observed at a follow-up of 24 months . No increase in operative times ( 52 vs 51 min tourniquet time ) or no complications were observed . Reduced blood loss was observed in the MIS group ( 590 vs 989 ml ) . Conclusion The MCL sparing limited medial parapatellar approach allows good surgical exposure , easy extension proximally if necessary , contained closure after surgery with less bleeding , faster recovery , full weight-bearing without aid and most importantly no radiological malalignment . Level of evidence Therapeutic study , Level II A prospect i ve r and omized study was performed on 20 patients undergoing one-stage bilateral knee arthroplasty . One knee was exposed using a st and ard median parapatellar arthrotomy and the other knee with a subvastus arthrotomy . All patients underwent quantitative strength testing before surgery and at 1 week , 1 month , and 3 months after surgery . The knees were also evaluated for range of motion , and patients , who were blinded as to the approach used , completed question naires at each evaluation period as to their preference , if any , regarding knee pain and level of function . There was no difference in the range of motion between knees exposed with the paramedian or subvastus arthrotomy at any time period . The subvastus knees demonstrated significantly greater strength at the 1-week and 1-month intervals , but there was no strength difference at the 3-month interval . There were more lateral releases performed in the paramedium knees , and three minor complications were related to the subvastus approach . Patients who expressed a preference chose the subvastus knee 4:1 over the paramedian knee . The subvastus approach offers a reasonable alternative to the paramedian arthrotomy and preserves greater quadriceps strength in the early postoperative period This prospect i ve r and omized study compared the clinical and radiological results of primary total knee arthropasty ( TKA ) using a mini-subvastus approach ( group I ; n = 35 ) or a st and ard approach ( group II ; n = 33 ) .  A posterior-stabilized prosthesis was used in both groups by the same surgeon . Mean follow-up was 18 months ( range 14 − 26 months ) . Patients in group I lost less blood and experienced less pain 1 day post-operatively . They achieved an active straight leg raise earlier and underwent less lateral retinacular releases . Functional outcome and the range of knee movements were significantly better in group I up to 9 months post-operatively , but there was no significant difference between the groups at 1 year post-operatively or at final follow-up . Reduced access and visibility in group I prolonged the operation time and result ed in five technical errors on radiographic evaluation . Based on these results , the authors currently only use the mini-subvastus approach for minimally invasive TKA in selected cases A prospect i ve , r and omized study was performed to compare early clinical and radiographic outcomes of total knee arthroplasty using either st and ard or minimally invasive surgical approaches . Fifty-nine patients were r and omized into 3 groups : a st and ard median parapatellar incision ( n = 19 ) , a " mini mid-vastus " ( n = 20 ) , or a " quad sparing " group ( n = 20 ) . The procedures were performed by a single surgeon using similar perioperative protocol s at 1 hospital . Postoperatively , the quad sparing group demonstrated some statistically significant ( P < .05 ) improvement in week 2 and greater but not in weeks 1 and 6 compared to the other groups . No significant differences occurred regarding postoperative complications or radiographic alignment of the implants . In conclusion , our study demonstrated that the quad sparing group had some improved early results without compromising safety or efficacy We present the peak outcome results of the Oxford medial unicompartmental arthroplasty through a minimally invasive surgical incision . This prospect i ve study included 78 Oxford medial unicompartmental knee replacements in 68 patients . At the 2 year review the patients achieved a mean Oxford Knee Score of 38.3 . This was not significantly different to the 2 year results of the phase 2 Oxford knee carried out using a st and ard parapatellar approach when patients achieved a mean OKS of 36.0 . Four unicompartmental knee replacements required revision for unexplained pain , deep infection , aseptic loosening and bearing dislocation .  Minimally invasive joint replacement is attractive to both patients and surgeons , but is technically dem and ing with complications inherent to limited access Although avoiding patellar eversion during a total knee arthroplasty ( TKA ) has theoretical benefit in quadriceps recovery , there has been paucity of supportive objective clinical results . We prospect ively design ed the study whether TKA without patellar eversion has better quadriceps recovery in an objective , dynamometer study . Seventy-two knees undergoing TKA with midvastus approach  were r and omized into two groups according to patellar eversion or not . Clinical data and objective quadriceps recovery using a dynamometer were investigated preoperatively and postoperative at 6weeks , 3months , 6months and 1year . There were no statistical differences between two groups throughout the follow-up periods in recovery of quadriceps force or power and clinical data . Choosing to evert patella during TKA using midvastus approach would not adversely affect postoperative quadriceps recovery We report the clinical and radiological results of a two- to three-year prospect i ve r and omised study which was design ed to compare a minimally-invasive technique with a st and ard technique in  total knee replacement  and was undertaken between January 2004 and May 2007 . The  mini-midvastus approach was used on 50 patients ( group A ) and a st and ard approach on 50 patients ( group B ) . The mean follow-up in both groups was 23 months ( 24 to 35 ) . The functional outcome was better in group A up to nine months after operation , as shown by statistically significant differences in the mean function score , mean total score and the mean Oxford knee score ( all , p = 0.05 ) . Patients in group A had statistically significant greater early flexion ( p = 0.04 ) and reached their greatest mean knee flexion of 126.5 degrees ( 95 degrees to 135 degrees ) 21 days after operation . However , at final follow-up there was no significant difference in the mean maximum flexion between the groups ( p = 0.08 ) . Technical errors were identified in six patients from group A ( 12 % ) on radiological evaluation . Based on these results , the authors currently use minimally-invasive techniques in total knee replacement in selected cases only Improvements in pain management techniques over the past decade have had a significant impact on the outcomes of total knee arthroplasty . Of these techniques , multimodal approaches have shown potential . The purpose of this study was to compare the results of periarticular injection ( PAI ) to a combination of patient-controlled epidural analgesia and femoral nerve block ( PCEA/FNB ) .  Ninety patients undergoing primary unilateral total knee arthroplasty between June 2010 and March 2011 were r and omized into 2 groups . The first group received the PCEA/FNB protocol , whereas the second group received the PAI .  Mean patient age was 66.1 ± 8.7 years . All patients were operated on using a similar st and ard medial parapatellar approach , and all received preemptive analgesia and postoperative pain protocol s. All patients were interviewed twice daily for the first 3 days postoperatively , once on day 7 , and once in month 6 . The 2 groups had similar readiness for discharge ( PCEA/FNB group , 3.3 ± 1.2 days ; PAI group , 3.2 ± 1.9 days ) . The results indicated no statistical difference between the 2 groups in 3 of 4 categories ( rest in the morning , rest in the evening , and ambulation in the morning ) . Pain on ambulation was the only category that was statistically lower in the PCEA/FNB group than in the PAI group . Although the study demonstrates similar results between the 2 groups , PAI can play a major role in postoperative pain control in institutions that may not have appropriately trained individuals , equipment , and re sources for PCEA/FNB . It also reduces many of the side effects and complications associated with regional anesthesia Summary Background Optimal positioning of implants and restoration of neutral mechanical axis are two primary surgical goals in total knee arthroplasty ( TKA ) . Despite modern instruments and improved surgical techniques , malalignment remains an important cause of early failure after TKA . The aim of this prospect i ve r and omized study was to compare the value of a new patient-matched instrument system ( PMI ) ( SignatureTM ; Biomet , Inc , Warsaw , Indiana ) to that of st and ard TKA surgical instrumentation ( STD ) in terms of coronal mechanical alignment , time of operation and blood loss . Patients and methods A total of 38 patients waiting for primary TKA were enrolled and r and omized into two groups ( 19 PMI and 19 STD ) . Magnetic resonance imaging was performed in all patients in the PMI group , and specific instruments for the femur and tibia were design ed preoperatively . All patients were operated on using the st and ard medial parapatellar approach with no use of tourniquet . Mechanical axis , time for the operation , and blood loss were evaluated . Results Patients in both groups had comparable age , body mass index , preoperative mechanical axis , Knee Society Score , and level of hemoglobin . Postoperative results showed that the PMI group fell significantly closer to neutral mechanical axis ( STD : 2.7 ± 1.7 , PMI : 1.7 ± 0.9 ; P = 0.013 ) with no outliers and a reduced time for the operation . There was no difference in the evaluation blood loss . Conclusions The use of PMI can contribute in achieving better mechanical axis with reduction in outliers and decreased operation time . Due to small differences between PMI and st and ard instruments , additional research are needed to confirm these preliminary results , and to discover potential benefits and functional improvements in the long-term outcome
The MSV approach ranked better concerning clinical scores ( the lowest visual analogic scale , the higher KSS and KSFS ) and functional outcomes ( the shortest straight leg raise , the greatest degree of flexion and range of motion ) .
Concerning perioperative data , the MSV evidence d the shortest hospital stay , while the MPP the shortest surgical duration and lowest estimated blood loss .
According to the main findings of the present study , the mini-subvastus approach for total knee arthroplasty demonstrated superior overall compared to the other approaches .
Alternatives to the classical medial parapatellar ( MPP ) approach for total knee arthroplasty ( TKA ) include the mini-medial parapatellar ( MMPP ) , mini-subvastus ( MSV ) , mini-midvastus ( MMV ) and quadriceps-sparing ( QS ) approaches .
The best approach has been not fully clarified .
The purpose of the present study was to conduct a Bayesian network meta- analysis comparing these approaches .