Treatment of Trochlear Dysplasia
The treatment of trochlear dysplasia can be very difficult. It is important to have a thorough workup to include a patient’s overall alignment, their tibial tubercle–trochlea groove angle (TT–TG), and an MRI scan to evaluate the status of the articular cartilage of their patellofemoral joint. This is important because surgical treatments may not always be indicated if there is significant arthritis present. In addition, a plain X-ray to look at the amount of patella alta, or a high-riding patella, is indicated.
The treatment of trochlear dysplasia can be very difficult. Patients who have a lateral patellar dislocation have a much higher risk of recurrence when they have trochlear dysplasia. Because the severity of trochlea dysplasia can run from minor to severe, treatment options are also varied. They can include a reconstruction of the medial patellofemoral ligament, a tibial tubercle osteotomy, a trochleoplasty, where the distal aspect of the femur is cut and reshaped to create more of a normal groove, a distal femoral osteotomy, and other associated treatments. Thus, no one patient has the same treatment as another, and a thorough workup is necessary to determine the best course of action, if any, for a particular patient with trochlear dysplasia.
Patients who have a trochleoplasty need to be non-weightbearing for 6 weeks after surgery. They are also placed into a continuous passive motion (CPM) machine for 6-8 hours a day while they are non-weightbearing. Motion is usually restricted to 90 degrees of knee flexion for the first two weeks after surgery and then increased to full knee motion as tolerated. After x-rays show sufficient healing of the trochleoplasty at 6 weeks postoperatively, patients are allowed to initiate weight bearing as tolerated and may wean off crutches when they can walk without a mill. The use of a stationary bike is also started with low resistance. After 3 months postoperatively, patients may initiate endurance and agility exercises. Full activities are allowed in patients without arthritis in their patellofemoral joint upon passing a sports test, usually at 7-9 months after surgery.