One-Stage Tricompartmental Hypoallergenic UKA for Tricompartmental Osteoarthritis: A Case Report.

Osteoarthritis (OA) is a degenerative and progressive joint disease. When all three compartments are involved, end-stage OA is treated with a total knee arthroplasty (TKA). Unicompartmental knee arthroplasty (UKA) is a primary treatment for isolated osteoarthritis. UKA has a quicker recovery time than TKA, as well as less morbidity and more tissue sparing. At the time of surgery, 17% of patients have a tricompartmental disease and most patients with a Kellegren-Lawrence grade >3 have an intact anterior cruciate ligament (ACL). Conventional TKA sacrifices the ACL. Patients with concurrent medial and lateral osteoarthritis and a functional ACL may receive a primary bi-unicondylar arthroplasty. Combined partial knee arthroplasty (CPKA) is an established practice either in bicompartmental femoro-tibial OA or in OA progression after UKA, with the addition of another UKA. A conversion of a lateral UKA to a tricompartmental joint replacement has been reported in the literature. In our case report, we describe a one-stage hypoallergenic tricompartmental UKA, with improved clinical score and no sign of early failure at the last follow-up.