Patellarealignment

Patellarealignment refers to procedures and therapies aimed at restoring proper tracking and alignment of the patella (kneecap) within the femoral trochlea, with the goals of reducing pain, improving function, and preventing dislocation or instability.

Causes and assessment of malalignment include trochlear dysplasia, patella alta (high-riding patella), an excessive Q-angle, ligamentous laxity, and weakness of the vastus medialis obliquus or hip stabilizers. Evaluation typically combines physical examination for patellar tracking and apprehension with imaging such as weight-bearing X-rays (Merchant or sunrise views) to assess patellar tilt and height (Insall-Salvati ratio) and MRI to evaluate soft tissues and trochlear morphology.

Nonoperative management emphasizes targeted physical therapy to strengthen the quadriceps, particularly the vastus medialis obliquus, as well as hip abductors and core stability. Supplemental options include patellar taping or bracing and activity modification. These measures aim to improve dynamic stabilization and reduce maltracking.

Surgical options are considered for recurrent dislocations or persistent maltracking after rehabilitation. Common procedures include medial patellofemoral ligament (MPFL) reconstruction to restore soft-tissue restraint against lateral displacement; tibial tubercle transfer with medialization or anteromedialization to realign the extensor mechanism; distalization for patella alta; and trochleoplasty in selected cases with high-grade trochlear dysplasia. Lateral release is less commonly performed today due to variable results and potential adverse effects.

Outcomes and prognosis depend on the underlying anatomy and appropriate patient selection. When indicated and correctly executed, realignment procedures can reduce instability and improve function, though risks include stiffness, over- or under-correction leading to new maltracking, fracture, nonunion, infection, and hardware irritation.