Unicompartmental total knee arthroplasty. A five- to nine-year follow-up study of 42 procedures.

Unicompartmental total knee arthroplasty is a controversial procedure, and only with long-term follow-up studies can its validity be appreciated. Thirty-six patients (42 knee procedures) were followed up for a period of 61 to 97 months (average, 67 months). Of the 42 knee procedures performed, 13 failures occurred, requiring revision. These failures resulted from loosening, primarily of the tibial component and in a great majority of the cases, were related to technique and prosthetic design. However, 62% of the patient population gained lasting pain relief, range of motion, and functional capacity.