title: Posterior femoral translation in medial pivot total knee arthroplasty of posterior cruciate ligament retaining type. Responsiveness and clinically important differences for the WOMAC and SF-36 after total knee replacement. No difference between double-high insert and medial-pivot insert in TKA No differences in functional results and quality of life after single-radius or multiradius TKA Patient preferences in knee prostheses. Long-term comparison of fixed-bearing and mobile-bearing total knee replacements in patients younger than fifty-one years of age with osteoarthritis. Validation study of WOMAC: a health status instrument for measuring clinically important patient relevant outcomes to antirheumatic drug therapy in patients with osteoarthritis of the hip or knee. Fixed versus rotating platform total knee arthroplasty: a prospective, randomized, single-blind study. Knee Arthroplasty With a Medially Conforming Ball-and-Socket Tibiofemoral Articulation Provides Better Function A mid-term clinical outcome study of the Advance Medial Pivot knee arthroplasty.
abstract: PURPOSE To report clinical results and demonstrate posterior femoral translation ( PFT ) in medial pivot total knee arthroplasty ( TKA ) of posterior cruciate ligament ( PCL ) retaining type . MATERIAL S AND METHODS A prospect i ve study was performed upon thirty consecutive subjects who were operated on with medial pivot TKA of PCL retaining type between March 2009 and March 2010 and had been followed up for at least 2 years . Clinical ly , the knee society knee score and function score were used . In full extension and active flexion lateral radiograph , anteroposterior ( AP ) condylar position and magnitude of PFT was determined . RESULTS At last follow-up , the mean knee society knee score and function score improved significantly compared to preoperative scores . The AP condylar positions were consistently posterior to midline throughout the entire range of flexion . The PFTs averaged 0.31 ( ±0.12 ) of half length of tibial base plate and were greater in higher flexion cases ( r = 0.56 , p = 0.0012 ) . There were no cases having either component migration or radiolucent line wider than 2 mm except for one case showing instability related to trauma . CONCLUSIONS In medial pivot TKA of PCL retaining type , clinical outcomes were satisfactory and posterior femoral translations were consistently observed during progressive flexions of knees at two- to three-year follow-up OBJECTIVES To study responsiveness and establish the minimal clinical ly important differences ( MCIDs ) and minimal detectable change ( MDC ) in patients undergoing total knee replacement ( TKR ) using the Short Form 36 ( SF-36 ) and Western Ontario and McMaster Universities Osteoarthritis Index ( WOMAC ) . METHODS Prospect i ve observational study in three public hospitals of all consecutive patients on waiting lists to undergo TKR intervention with diagnosis of knee osteoarthritis ( OA ) . Patients were asked to complete before the intervention and at 6 months and 2 years afterward the  SF-36 and the WOMAC health-related quality of life question naires ( HRQoL ) , and additional transition questions which measured the changes in their joint at 6 months . In both question naires the possible range of values is from 0 to 100 points . RESULTS In WOMAC improvement at 6 months after a TKR was between 27 ( stiffness ) and 31 points ( pain ) . The SF-36 showed improvements between the 28.3 points of role physical and 2.79 of general health . From 6 months to 2 years , WOMAC improvements were between 2 and 6 points . The MCID ranged from 14.52 ( stiffness ) to 22.87 ( pain ) on the WOMAC and in the physical domains of SF-36 from 11.56 ( physical function ) to 16.86 ( bodily pain ) . On the WOMAC , the MDC ranged from 13.11 ( function ) to 29.12 ( stiffness ) , and on SF-36 from 19.50 ( physical function ) to 41.23 ( social functioning ) . CONCLUSIONS The MCID for TKR is around 15 on WOMAC , while with the SF-36 of at least 10 points . These values should not be considered as absolute thresholds Abstract Purpose To compare the clinical midterm results in ADVANCE total knee arthroplasty ( TKA ) with double-high ( DH ) insert , with same type implant with medial-pivot ( MP ) insert . Method Forty ADVANCE TKAs were r and omly divided into two groups , and two different design insert , DH insert , and MP insert were used in each group . At midterm , 4–5 years after surgery , Knee Society Scores ( KSS ) , Knee Society Functional Scores ( KSFS ) , range of motion ( ROM ) , and UCLA activity score were assessed and reported in this study . Results Midterm clinical results , including ROM and KSS , were comparable with both groups . KSFS and UCLA activity score were equally good between the two groups . Conclusion The results in this study revealed equally good clinical results with these types of implants at midterm follow-up , although the significant better ROM has not achieved by using DH insert . We concluded that the selection of inserts only could not achieve the better clinical results , including ROM and activity level in this study .Level of evidence Therapeutic studies —investigating the results of treatment , Level II Abstract Purpose The main objective of this study was to compare the functional results and the impact on quality of life after a  single-radius or a multiradius TKA implantation .  The secondary objectives were to compare range of motion , satisfaction and the ability to perform daily life activities with both types of implant . It was hypothesized that the single-radius TKA would lead to better functional results and better quality of life than the multiradius TKA . Methods This is a prospect i ve non-r and omized study that included 250 cases of a single-radius TKA and 224 of a multiradius posterior-stabilized TKA implanted with the same surgical and rehabilitation protocol .  Results In the 1- and 5-year follow-up , we found similar knee KSS scores ( 89.7 ± 12.1 in the multiradius group and 90.3 ± 11.7 in the single-radius group ) and functional KSS scores ( 78.6 ± 21.4 in the multiradius group and 75.8 ± 20.9 in the single-radius group ) . The pain and the Physical SF-36 scores were also similar . Range of motion ( 112 ° ± 12 ° in the multiradius group and 112 ± 12 ° in the single-radius group ) , patients ’ satisfaction and the ability to perform daily life activities were also similar in both groups . Conclusion The use of a single-radius or a multiradius posterior-stabilized knee prosthesis can improve the function of the knee and the patients ’ quality of life in a similar way at the short-term and midterm follow-up . Moreover , range of motion , patient satisfaction and the ability to perform daily life activities are similar with both types of prosthesis . As both types of prosthesis can improve the function and quality of life of the patients in a similar way , the sagittal radius of the femoral component should not be considered the main factor when choosing the model of TKA.Level of evidence Therapeutic study : Prospect i ve comparative study , Level A total of 344 patients underwent bilateral total knee replacement ( TKR ) using a different prosthesis on each side . Four knee prostheses were used : anterior and posterior cruciate-retaining ( ACL-PCL ) , posterior cruciate-retaining ( PCL ) , medial or lateral pivot ( MLP ) , and posterior cruciate-substituting ( PS ) . All patients had good or excellent results . The range of movement , relief from pain , alignment , and stability did not vary among any of the prostheses . Forty-one of 46 patients ( 89 % ) preferred the ACL-PCL to the PS knee and 27 of 35 patients ( 77 % ) the MLP knee to the PS knee . Of the patients with an ACL-PCL knee on one side and a MLP on the other , an equal number preferred each type . The MLP knee was preferred to the PCL by 34 ( 79 % ) patients . PS and PCL knees were preferred equally . Patients with bilateral TKRs preferred retention of both their cruciate ligaments or substitution with a medial or lateral pivot prosthesis BACKGROUND There is limited information comparing the results of fixed-bearing total knee replacement and mobile-bearing total knee replacement in patients with osteoarthritis who are younger than fifty-one years and who have a fixed-bearing implant in one knee and a mobile-bearing implant  in the other . The purpose of this study was to compare our long-term clinical and radiographic results of fixed-bearing total knee replacement and mobile-bearing total knee replacement in a group of patients from this population . METHODS We prospect ively compared the results of 108 patients with osteoarthritis who were younger than fifty-one years ( mean age , forty-five years ) who had received a fixed-bearing prosthesis in one knee and a rotating platform mobile-bearing prosthesis in the other .  The mean follow-up was 16.8 years ( range , fifteen to eighteen years ) . The patients were assessed clinical ly and radiographically . Knee motion and function were assessed as a primary outcome . Patients were assessed with question naires , and each knee was assessed separately . RESULTS Although there was significant improvement in both groups of knees , there was no significant difference between the groups ( i.e. , fixed-bearing and mobile-bearing knees ) with regard to the mean postoperative knee motion ( 126 ° and 128 ° , respectively ; p = 0.79 ) , the mean Knee Society knee clinical score ( 95 and 94 points , respectively ; p = 0.79 ) , or the Knee Society knee functional score ( 84 and 85 points , respectively ; p = 0.19 ) at the latest follow-up . In the fixed-bearing group , one knee was revised because of infection , two for aseptic loosening of the tibial component , and two because of wear of the tibial polyethylene insert . In the rotating platform mobile-bearing group , two knees were revised because of instability and one because of infection . The Kaplan-Meier survivorship for revision at 16.8 years of follow-up was 95 % ( 95 % confidence interval , 91 to 100 ) for the fixed-bearing prosthesis and 97 % ( 95 % confidence interval , 93 to 100 ) for the rotating platform mobile-bearing prosthesis . CONCLUSIONS Long-term results of both fixed and mobile-bearing total knee arthroplasties were encouraging in patients who were younger than fifty-one years of age with osteoarthritis . However , we found no superiority of the mobile-bearing total knee prosthesis over the fixed-bearing total knee prosthesis Within the context of a double blind r and omized controlled parallel trial of 2 nonsteroidal antiinflammatory drugs , we vali date d WOMAC , a new multidimensional , self-administered health status instrument for patients with osteoarthritis of the hip or knee . The pain , stiffness and physical function subscales fulfil conventional criteria for face , content and construct validity , reliability , responsiveness and relative efficiency . WOMAC is a disease-specific purpose built high performance instrument for evaluative research in osteoarthritis clinical trials The purpose of this r and omized , single-blind clinical trial was to compare a rotating platform ( RP ) total knee arthroplasty to a fixed-bearing ( FB ) total knee arthroplasty . Ninety-five knees in 69 patients were implanted by 2 surgeons . There were no significant differences in the preoperative demographics . At a minimum of 2-year follow-up , clinical outcomes and complication rates were similar , with the exception that the RP group had significantly better stair-climbing scores ( P = .04 ) . Postoperative range of motion was equally good in both groups ( FB knees , 1 ° -125 ° ; RP knees , 1 - 126 ° ) . There were no bearing dislocations in the RP group . In conclusion , this RP design performs at least as well as the FB version , and the RP patients reported better stair-climbing ability . Enthusiasm for this finding should be tempered by the relatively small sample size Background A knee design with a ball- and -socket articulation of the medial compartment has a femoral rollback profile similar to the native knee . Compared to a conventional , posterior-stabilized knee design , it provides AP stability throughout the entire ROM . However , it is unclear whether this design difference translates to clinical and functional improvement . Questions / purpose sWe asked whether the medially conforming ball- and -socket design differences would be associated with ( 1 ) improved ROM ; and ( 2 ) improved American Knee Society , WOMAC , Oxford Knee , SF-36 , and Total Knee Function Question naire scores compared to a conventional , fixed-bearing posterior-stabilized TKA . Patients and Methods We enrolled 82 patients in a single-center , single-blinded , r and omized , controlled trial comparing the medially conforming ball- and -socket design knee prosthesis to a posterior-stabilized total knee prosthesis .  Our primary end point was ROM . Our secondary end points were American Knee Society , WOMAC , Oxford Knee , SF-36 , and Total Knee Function Question naire scores . All patients were followed at 1 and 2 years . Results The mean ROM was 100.1 ° and 114.9 ° in the posterior-stabilized and medially conforming ball- and -socket groups , respectively . The physical component scores of SF-36 and Total Knee Function Question naire were better in the medially conforming ball- and -socket group . We found no difference in American Knee Society , WOMAC , and Oxford Knee scores . Conclusions Both implant design s similarly relieved pain and improved function . The medially conforming ball- and -socket articulation provided better high-end function as reflected by the Total Knee Function Question naire . Level of Evidence Level I , therapeutic study . See Guidelines for Authors for a complete description of levels of evidence The Advance Medial Pivot Total Knee Arthroplasty ( Wright Medical Technology , Arlington , Tennessee , USA ) has been design ed to reproduce modern ideas of knee kinematics . We report a prospect i ve clinical outcome study of 284 arthroplasties in 225 consecutive patients with a mean follow-up of 6.7 years ( range 4 to 9 years ) . For evaluation , both  objective and subjective clinical rating systems  and serial radiographs were used . At final follow-up , 10 ( 4.4 % ) patients ( 10 knees ) only were lost from follow-up and four ( 1.8 % ) patients ( five knees ) had died for reasons unrelated to the surgery with their knees performing well . There was an 82 % compliance in the intervals of follow-up evaluation . All patients showed a statistically significant improvement ( p=0.01 ) in the Knee Society clinical rating system , WOMAC question naire , SF-12 question naire , and Oxford knee score . The majority of patients ( 92 % ) were able to perform age-appropriate activities with a mean knee flexion of 117 degrees ( range 85 degrees to 135 degrees ) at final follow-up . Survival analysis showed a cumulative success rate of 99.1 % at 5 years . Two ( 0.7 % ) arthoplasties , in which patient selection and surgical errors were identified , were revised due to aseptic loosening , one due to infection and one due to a traumatic dislocation . This study demonstrates satisfactory mid-term clinical results for this knee design
target: Conclusion Based on the small number of studies with appropriate statistical analysis , we are unable to reach a clear conclusion in the clinical performance of medial stabilized knee replacement construct .
background: Background Medial stabilized  total knee joint replacement ( TKJR ) construct is design ed to closely replicate the kinematics of the knee .
  Little is known regarding comparison of clinical functional outcomes of patients utilising vali date d patient reported outcome measures ( PROM ) after medial stabilized TKJR and other construct design s. Purpose To perform a systematic review of the available literature related to the assessment of clinical functional outcomes following a  TKJR  employing a medial stabilized construct design .