Unicompartmental knee arthroplasty: is it durable?
OBJECTIVE
To analyse the long-term durability of unicompartmental knee arthroplasties using the Marmor/Mod 2 prosthetic.


METHODS
Survivorship analysis was used to retrospectively evaluate 113 medial unicompartmental knee arthroplasties performed between 1974 and 1989 in two New Plymouth hospitals. An outcome was determined for every case.


RESULTS
The survival rate was 95% at 10 years and 85% at 15 years. All 27 knees surviving at the time of the study were assessed clinically using the Knee Society Score, and 25 of the 27 knees underwent radiographic evaluation. The Knee Society Knee and Knee Society Functional scores were 72 points and 56 points respectively for the group of 27 surviving prostheses, and the 25 knees X-rayed showed no loosening or fracture of the prosthesis.


CONCLUSIONS
Unicompartmental knee arthroplasty with the Marmor/Mod 2 prosthesis has provided satisfactory long-term durability in this cohort of elderly patients, in comparison with similar published studies featuring other prostheses.
Auckland Hospital, Auckland, New Zealand.
Steven
S
Yang
Simon
S
Hadlow
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000379:methods; D005260:Female; D006801:Humans; D007720:Knee Prosthesis; D008297:Male; D008875:Middle Aged; D011475:Prosthesis Failure; D012189:Retrospective Studies; D016896:Treatment Outcome