Anterior Dislocations of the Tibia after Total Knee Arthroplasty. A Case Report

We experienced a rare case of anterior dislocation of the tibia after total knee arthroplasty (TKA). A 61-year-old female, suffering from RA, was treated with left TKA with Mark IV at another hospital in 1997. After operation, joint laxity of her left knee appeared, and for which wore a knee outfit for 2 months. She noticed left knee pain for no apparent reason in March in the 2000. She came to our hospital in September due to increased knee pain. We found anterior dislocation of the tibia and an old fracture of the fibula in roentgenogram, and manual reduction failed. We were alde to reduce the knee joint during surgery by flexing it, but dislocation easily occurred by extending the knee joint. Although the posterior part of UHMWPE of the tibial conponent was worn out, both collateral ligaments were not lax in the reduced position. We performed revision TKA with Nexgen-LPS. 10 weeks after surgery, she was able to walk without brace and the ROM of her left knee was 0° in extension and 125° in flexion.