A trochleoplasty is a rare procedure that is performed in patients that have type B or type D trochlear dysplasia. In these patients, the trochlea can be either flat or dome shaped, which results in severe instability of the patellofemoral joint.
Description of a Trochleoplasty
A trochleoplasty is performed by reshaping the distal aspect of the femur. In this circumstance, guide pins are placed along the undersurface of the trochlea cartilage surface and a saw is used to undermine the articular cartilage. A V-shaped groove is then prepared in the distal femur, and the articular cartilage is positioned down into the V to reconstitute the bony groove. A trochleoplasty is rarely performed as a primary procedure, and most often is performed after patients have failed other types of reconstructions, including a MPFL reconstruction. Because of the complex nature of these problems, a trochleoplasty can also be commonly performed with a distal femoral osteotomy, a medial patellofemoral ligament reconstruction and/or a tibial tubercle osteotomy.
For this reason, the patient needs a thorough clinical exam, radiographic work up, and evaluation of the status of the articular cartilage prior to undergoing a trochleoplasty to obtain the best chance of an optimal outcome.