REVISION OF FAILED UNICOMPARTMENTAL KNEE REPLACEMENTS TO TOTAL KNEE REPLACEMENTS

Abstract

Unicompartmental knee replacements have been performed since the 1970’s. Controversy still exists as to the indications and contra-indications for these procedures, and there is still no clarity as to whether the patient should have a high tibial osteotomy, a unicompartmental knee replacement, or a total knee replacement. It has been suggested that unicompartmental knee replacements are preferable to high tibial osteotomies, as conversion to a total knee replacement is easier following a unicompartmental replacement.

Ten patients with unicompartmental knee replacements presented to the author requiring revision. All were revised to total knee replacements. In four a primary knee replacement could be performed, but the remaining six required a revision prosthesis on the tibial side, using stems and wedges. No revision prostheses were required on the femoral side.

Revision of a unicompartmental total knee replacement is technically easier than the revision of a total knee replacement. Revision of a high tibial osteotomy to a total knee replacement can be difficult, particularly if a poorly performed HTO had been done, with residual significant ligament imbalance.

The author feels that any type of revision surgery can be difficult. The author concludes that there is still no clarity as to whether one should do a unicompartmental knee replacement or a high tibial osteotomy, and that currently it is still the Surgeon’s choice as to which procedure he is going to perform.