What have we learned from LCS mobile-bearing knee system?
Three hundred and sixty-four low contact stress (LCS) total knee arthroplasties that could be followed up for more than 5 years were clinically and radiographically analyzed. The median postoperative Hospital for Special Surgery score improved from 56 (range 32-77) to 91 (range 64-100) points, but median range of motion did not change from 120° (range 50°-135°) to 120° (range 85°-135°). Complications occurred in 16 cases (4%), and included postoperative polyethylene dislocation and intraoperative tibial condylar fracture, while five knees (1%) required revision surgery due to mechanical reasons. The overall prosthesis survival rate was 91% at 12 years. Although the LCS mobile-bearing knee system has theoretical advantages in terms of wear and loosening, the problem of polyethylene dislocation, intraoperative tibial fracture, and radiolucent lines should be solved for long survival. The clinical relevance of this study is that the LCS system provided good clinical and survival results.
Cho
Woo-Shin
WS
Department of Orthopedic Surgery, Asan Medical Center, Ulsan University College of Medicine, 388-1 Pungnap-dong, Songpa-gu, Seoul 138-736, Korea. wscho@amc.seoul.kr
Youm
Yoon-Seok
YS
Ahn
Sung-Chan
SC
Sohn
Dong-Wook
DW
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D001172:Arthritis, Rheumatoid / Q000000981:diagnostic imaging / Q000601:surgery; D019645:Arthroplasty, Replacement, Knee / Q000379:methods*; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007720:Knee Prosthesis; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000000981:diagnostic imaging / Q000601:surgery; D010020:Osteonecrosis / Q000000981:diagnostic imaging / Q000601:surgery; D011183:Postoperative Complications / Q000503:physiopathology; D011474:Prosthesis Design; D011475:Prosthesis Failure; D011859:Radiography; D016059:Range of Motion, Articular / Q000502:physiology*; D012086:Reoperation / Q000706:statistics & numerical data; D012189:Retrospective Studies; D012720:Severity of Illness Index; D018709:Statistics, Nonparametric; D013314:Stress, Mechanical; D013997:Time Factors; D016896:Treatment Outcome