Early failure of unicompartmental knee arthroplasty

We are reporting the relatively poor results obtained in patients receiving a unicompartmental knee arthroplasty (UKA). Thirty-six patients underwent 39 UKAs from December 2002 to June 2004. All received a DePuy Preservation design (DePuy, Warsaw, In) with an all-poly tibial component. The patients' mean age was 60 years, with an equal distribution of men to women. Of the 39 UKAs, 15 (38%) failed at 9 to 12 months postoperative. All the failures were secondary to loosening of the femoral component. No correlation to failure was found between preoperative anteroposterior (AP) angle, postoperative AP angle, amount of correction obtained, postoperative posterior tibial slope, lateral femoral component alignment, postoperative range of motion, sex, or size of the patient.