[Minimally Invasive Stryker-Osteonics unicondylar knee prosthesis with metal-backed tibia component: a 5-year follow-up].
BACKGROUND
The aim of this study was to evaluate the medium-term results of minimally invasive unicompartmental knee joint arthroplasty with a metal-backed tibia component.


METHODS
Ninety-one unicompartmental knee replacements with a metal-backed tibia component, type SCR-Stryker Osteonics, were implanted in a minimally invasive technique in 91 patients between 1997 and 1999. The evaluation of medium-term results was based on The Knee Society Clinical Rating System by Insall and Scott and was done at 6 weeks, 1, 3 and 5 years after surgery. This rating system is based on the clinical and symptoms of the patient (maximum score 100).


RESULTS
Preoperatively, the average knee score was 57.6 (44-66), the function score 63.3 (48-71). Throughout the period of investigation all patients had an increased knee and function score. One year after surgery the knee and function scores increased to 94.8 (39-100) and 93.6 (75-100). Five years post-implantation only 64 patients could be re-evaluated but they also had a knee and function score corresponding to the 3-year results [knee score: 98.2 (94-100); function score: 98.9 (85-100)]. Revision surgery using a total knee prosthesis was performed in 3 cases.


CONCLUSIONS
The unicompartmental knee arthroplasty was a good surgical method for managing medial, unicompartmental arthritis of the knee joint. The results presented by the authors and corroborated by many literature data provide evidence that unicompartmental arthroplasty is of great importance in the treatment of unicompartmental knee arthritis. The results achieved by the minimally invasive technique of a unicompartmental knee arthroplasty with a metal-backed tibia component of the type Stryker-Osteonics were equal to the conventional surgical technique in literature. Good indications were patients older than 60 years with normal weight and normal sports activity. Well-functioning collateral and cruciate ligaments were mandatory. Moreover, the minimally invasive technique may lead to a shorter time of rehabilitation because of the reduced soft tissue damage.
Endres
S
S
Klinik für Orthopädie und Rheumatologie der Philipps-Universität Marburg. endres@med.uni-marburg.de
Steinheiser
E
E
Wilke
A
A
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000295:instrumentation* / Q000706:statistics & numerical data*; D005260:Female; D005500:Follow-Up Studies; D005858:Germany / Q000453:epidemiology; D006801:Humans; D007720:Knee Prosthesis / Q000706:statistics & numerical data*; D008137:Longitudinal Studies; D008297:Male; D008670:Metals; D008875:Middle Aged; D019060:Minimally Invasive Surgical Procedures / Q000295:instrumentation* / Q000706:statistics & numerical data*; D020370:Osteoarthritis, Knee / Q000453:epidemiology* / Q000601:surgery*; D011379:Prognosis; D020127:Recovery of Function; D012086:Reoperation / Q000706:statistics & numerical data; D018570:Risk Assessment / Q000379:methods; D012307:Risk Factors; D013977:Tibia / Q000601:surgery; D016896:Treatment Outcome
D008670:Metals