Abstract
Introduction: Medial unicompartmental knee replacement (UKR) is a successful procedure in the management of early osteoarthrosis. This procedure is not usually indicated in patients who have insufficiency of the anterior cruciate ligament (ACL). However, a problem arises when, after a UKR, an ACL rupture occurs, and instability develops. A technique is described to stabilise the knee and possibly avoid conversion to total knee replacement.
Methods: Three patients underwent arthroscopic ACL reconstruction. Only semitendinosus tendon was used. The proximal fixation was with a Mulch screw (Biomet) and the distal fixation was with two screws and washers. A post-operative, standard, accelerated rehabilitation programme was used in all three.
Results: After two years, two patients continued playing doubles tennis, and one continued as a dancing instructor.
Conclusions: While an ACL-related instability is a contraindication to undertaking a UKR, the disruption of an ACL in a well functioning UKR and the development of instability need not necessarily force the conversion to TKR. Using a modified hamstring reconstruction it was possible to stabilise the knee and maintain the UKR function.
The abstracts were prepared by Professor A. J. Thurston. Correspondence should be addressed to him at the Department of Surgery, Wellington School of Medicine, PO Box 7343, Wellington South, New Zealand
