Tuberosity Surgery: What is the Role of Distalization?

Patellofemoral instability, also referred to as episodic patella dislocation (EPD), occurs at an incidence of 7 per 100,000 people across all age groups. Many anatomical factors are known to contribute to EPD. The most common of these are trochlea dysplasia and patella alta. Patella alta is increasingly being recognized as a main contributing factor in EPD. This morphologic abnormality exists when the patella is located in an exaggerated proximal position such that it does not engage in the trochlea appropriately. The exact biomechanical mechanism that links patella alta to EPD is unclear, but it is likely to be multifactorial. A delay in patellofemoral contact and engagement predisposes to patella dislocation and potentially increased rates of patellofemoral osteoarthritis. Surgical management of patella alta in the setting of EPD aims to restore patella height and patella tendon length back to normal indices. The goal is to improve patellofemoral engagement and prevent further patella dislocations. The recommended procedures include a distalizing tibial tubercle osteotomy and patella tendon tenodesis, which are frequently combined with other procedures to stabilize the patella. Overall, excellent surgical results have been recorded for these procedures in the short term to medium term