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Objective To determine the effects of gender on distal femoral aspect ratio (DFAR),femoral component fit,and clinical outcomes at 2 years after total knee arthroplasty (TKA).Methods From December 2012 to December 2014,the clinical and radiographic characteristics of 107 consecutive patients (109 knees) were studied prospectively.All patients were divided into two groups according to gender:33 cases (33 knees) were male and 74 cases (76 knees) were female.These subjectives underwent unilateral primary TKAs for end-stage osteoarthritis by using Vanguard high-flex open-box posterior-stabilized fixed-bearing prosthesis.The anterior-posterior size increment of the Vanguard femoral components was 2 mm.The clinical outcomes (Knee Society Score,Western Ontario and McMasters University osteoarthritis index,time-up-to-go test,chair rise test,stair-climbing test,range of flexion,extensor lag,flexion contracture,anterior knee pain score and patient satisfaction) between two groups were compared at 2 years postoperatively.The femoral component fit and two kinds of DFARs were also compared intraoperatively.Results The total overhang value in zone 2 was-5.51±4.46 mm in male and-3.24±3.93 mm in female,respectively.That in zone 3 was-5.99±4.73 mm in male and-3.45±3.98 mm in female.The total underhang value in male was significantly higher than that in female (P＜0.05).The rate of significant underhang in zone 3 was significantly higher in male than that in female (60.6％,23.7％,P＜O.05).Two kinds of DFARs in male were significantly higher than those in female (1.56±0.12 vs.1.51±0.12,1.28±0.08 vs.1.24±0.11,P＜0.05).Compared with intra-operative range of flexion (ROF) in the condition of 90° hip flexion after prosthesis implantation,the loss of ROF against gravity and the loss of passive ROF at 2 years postoperatively were statistically significant higher than those in female (-8.73°±7.71° vs.-4.82°±6.67°,-11.45°±8.78° vs.-7.34°±8.71°,P＜0.05).In the male group,the natural ROF after capsule closed (132.85°±6.01°) was significantly larger than that of the female group (128.78°±6.34°),but there was no significant difference in passive flexion.The change of non-weight-bearing passive ROF (1.67°± 14.76°),the Knee Society stairclimbing score (45.15±7.12) and the proportion of being able to squat and rise (97.0％) in male group were greater than those in female group,postoperatively.Conclusion Although DFAR is different within gender;it has little effects on early outcomes after unisex posterior-stabilized TKA.The loss of ROF in male is more prominent than that in female.Increased size offerings of femoral components improve fit in female distal femur.However,distal femur of male still exist obvious underhang.
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Objective To compare the effect of preservation or complete excision of infrapatellar fat pad (IPFP) on clinical outcomes after total knee arthroplasty (TKA) at one year follow-up.Methods We randomized 100 patients (100 knees) undergoing TKA into two groups from June 2014 to August 2015,16 male and 78 female,with the average of 62.37 years old (range from 48 to 75).In excision group,50 patients underwent TKA with complete IPFP excision and in preservation group,50 patients received TKA without IPFP excision.We compared the outcome at postoperative 1 year between the two groups.Wound complication rate and patellar tendon injury rate were also evaluated.Results Complete follow-up data were available on 94 patients (46in preservation group and 48 in excision group).There were no intraoperative patellar tendon injury and postoperative wound complication cases.The patellar tendon length of excision group and preservation group at 1 week was (40.35±6.05) mm and (40.56±6.17) mm,and at 1 year were (36.18±7.09) mm and (38.75±6.23) mm,there were no statistical differences between the two groups.The patellar tendon shortening at postoperative 1 year in excision group was (-4.18±3.52) mm,more than preservation group which was (-1.81±2.08) mm,and there was statistically significant difference between the two groups.One year postoperatively,the anterior knee pain score in preservation group 2.42±2.19 was lower than excision group excision group 0.93± 1.40,and anterior knee pain rate was 2.2％ and 18.8％ in each group,the difference were all statistically significant.The Knee Society (KS) scores,knee flexion,flexion contracture,patient satisfaction score,and patient satisfaction rate had no statistical differences between the two groups.Conclusion Complete resection of IPFP results in a significant patellar tendon shortening and a higher probability of occurrence of knee pain after 1 year of TKA.Retention of IPFP did not increase the risk of patellar tendon injury and should therefore be kept as much as possible for complete IPFP.
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Objective To detail our early experience on a modified two-stage revison using articulating antibiotic-loaded cement spacer (AALCS) for late periprosthetic infection of total knee arthroplasty (TKA).Methods From January 2006 to February 2009,a series of 21 patients (21 knees) underwent twostage revision knee arthroplasty for late infected TKA.There were 8 males and 13 females,aged from 56 to 83 years (average,64.4 years).In the first stage,each patient underwent radical debridement,removal of all components and cement,and implantation of articulating cement spacer containing vancomycin.Graduated knee motion and partial weight bearing activity were encouraged in the interval period.Each patient received an individual systemic organism-sensitive antimicrobial therapy for 4.9 weeks (range,2-8 weeks) followed by a second-stage revision TKA.All the patients were regularly followed-up using the American Knee Society Scoring System.Results All patients were followed up for 17 to 54 months (average,32.2 months).At final follow-up,the knee society score,function score,pain score and range of motion (ROM) of knee were significantly improved compared with those before operation.Meanwhile,there was no significant increase in the degree of extension lag.The average interval period was 11.5 weeks (range,6-32 weeks).No change of bone defect volume was found between two stages.There were no complications such as recurrent infection,hepatic and renal dysfunction,and deep venous thrombosis.Conclusion Treating infected TKA with AALCS can avoid spacer-related bone loss,preserve knee function between two stages,and eradicate infection effectively without significant complications.The early clinical results are inspiring.Radical debridement,individual application of systemic antibiotics,and reasonable juncture for the second revision are all key factors related to a successful outcome.
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[Objective]To investigate the advantages, risks and kye points of minimally invasive total knee arthroplasty with subvastus approach. [Method] From April 2005 to December 2006, 204 primary total knee arthroplasties were performed, among them 146 cases with convention incision (CI), 58 cases with minimally invasive subvastus approach(MIS). All knees were implanted with the same prosthesis (NEXGEN-LPS, Zimmer).The anesthesia time,operation time, hospitalization time were recorded.The first walking time, walking distance, active knee range of motion, preoperative and postoperative HSS Score and the complications were compared. [Result] Totally 204 cases were followed up and the mean follow-up time was 22 months (range, 13-36 months). The difference of anesthesia time, length of incision, operation time, hospitalization time, walking time had significance between the CI and MIS groups ( u test, P0.05). The difference of active range of motion in 24 hours, 1 week, 2 weeks postoperation had significance between the two groups ( u test, P0.05).The difference of HSS score in 24 hours, 1 week, 2 weeks after operation had significance between the two groups ( u test, P0.05). [Conclusion] The minimally invasive total knee arthroplasty with subvastus approach reduces the quadriceps injury, offers early active knee motion and quickly recovery of knee function. However there is no significant difference in long-term walking distance, range of motion and HSS score.