FEMORAL COMPONENT DISLOCATION IN UNICONDY LAR KNEE PROTHESIS - A CASE-REPORT

Introduction Femoral component dislocation in unicondylar knee arthrop lasty is rare. One case is reported. Material and methods A 59 years o ld man required revision of his unicondylar knee arthroplasty for loos ening and dislocation of the femoral component 3 years after its inser tion. Revision was performed and we found a technical error: distal an d posterior femoral cut was too thin, and with components in glace, th ere was a tendancy for the components to ''rock'' as the knee was flex ed. The implants were too thight in flexion. A new unicondylar knee ar throplasty was performed. Discussion The posterior condylar bone resec tion should reach at least the thickness of the metal implant. It is b etter to resect slightly too much of the posterior condyle than too li ttle in order to avoid tightening of the knee in flexion. The femoral component must accurately reproduces the anterior - posterior dimensio n of the femoral condyle. Conclusion With better selection of patients and surgeons who are more familiar to this type of procedure loosenin g and dislocation Of an unicondylar knee arthroplasty should be avoide d.