Tibial tuberosity transfer for episodic patellar dislocation.

Numerous surgical techniques have been described to address episodic patellar dislocations. Some of them involve the soft tissues whereas others primarily address a bony correction. Four principal anatomic factors have been identified that increase the risk for episodic patellar dislocations: trochlear dysplasia, patella alta, patellar tilt, and an excessive tibial tubercle-trochlear groove distance. A treatment algorithm has been proposed to correct each of these factors. It includes the tibial tuberosity transfer, which is able to correct both a patella alta and an excessive tibial tubercle-trochlear groove distance. The tibial tuberosity can be transferred distally or medially or more frequently a combination of both. It will realign the extensor mechanism and increase patellofemoral stability. This procedure may be associated with a medial patellofemoral ligament reconstruction in case of excessive patellar tilt or rarely with a trochleoplasty for major abnormal patellar maltracking.