J Orthop Traumatol. 2014 Mar;15(1):59-62. doi: 10.1007/s10195-013-0250-2.
Unicompartmental knee replacement (UKR) is now established as a treatment for medial compartment arthritis. The Oxford UKR (Biomet Orthopedics, Inc, Warsaw, IN, USA) has a mobile-bearing system, which minimizes wear. This has been shown to provide excellent long-term results. Dislocation of the mobile-bearing device is rare with an incidence of 1 in 200 (0.5 %). The treatment usually involves exploration of the knee through the original anteromedial incision, removal of the dislocated bearing and rectification of the underlying cause for the dislocation. We describe two cases of a posterior dislocation in which the mobile bearing could not be retrieved and was left in situ. In both cases a good outcome was achieved. We conclude that in extremely rare cases where a dislocated bearing has migrated posteromedially and cannot be retrieved, it can be left in place rather than exploring the joint acutely through a separate posterior incision.
单髁膝关节置换术（UKR）现已成为治疗内侧间室关节炎的一种方法。牛津 UKR（Biomet Orthopedics，Inc，美国印第安纳州华沙）采用活动衬垫系统，可最大程度地减少磨损。事实证明，这种方法可带来出色的长期效果。活动衬垫装置脱位的发生率为 1/200（0.5%），较为罕见。通常需要通过原前内侧切口对膝关节进行探查，取出脱位的衬垫，并纠正导致脱位的根本原因。我们描述了两例后脱位的病例，其中无法取出活动衬垫，只能将其留在原位。在这两种情况下，都取得了良好的效果。我们得出的结论是，在极为罕见的情况下，如果脱位的衬垫向后内侧迁移且无法取出，则可以将其留在原处，而无需通过单独的后入路急性探查关节。
