A Technique for Lateral Unicompartmental Arthroplasty: A Road Less Traveled

We describe the technique for performing lateral unicompartmental arthroplasty through either a medial or lateral parapatellar approach. A lateral unicompartmental arthroplasty is a technically more demanding procedure than its more common medial counterpart. Studies that exist on lateral unicompartmental arthroplasty show good outcomes. The key steps to the procedure involve a figure-of-four leg position to improve visualization of the lateral compartment, avoiding patella femoral impingement by downsizing the femoral component, avoiding external rotation of the tibial component, and lateralizing the femoral component to improve contact with the tibial implant.