Current concepts in the surgical management of patellar instability.

BACKGROUND: Patellar instability is a common condition, and recurrent instability can be highly disabling. It is important to understand the patho-anatomy of patellar instability in order to treat it effectively, with the trochlear shape, patellar height and the integrity of the medial retinaculum being the most important factors in determining the risk of ongoing instability. CLINICAL ASSESSMENT AND RADIOGRAPHIC ASSESSMENT: Clinical assessment is based around correct diagnosis of instability, identification of at risk features and an assessment of neuromuscular control and factors that may affect the potential for rehabilitation before or after surgery. Radiology is important to assess features predisposing to instability and to determine the best treatment plan for each individual. TREATMENT: There are a range of surgical options for the treatment of patellar instability and these should be chosen based on an each patients individual patho-anatomy. Lateral release is not recommended as a treatment for patellar instability. Medial patello-femoral ligament reconstruction, tibial tubercle distalisation, trochleoplasty or occasionally tibial or femoral osteotomies for correction of rotational or coronal plane mal-alignment may all be used either individually or in combination. High quality physiotherapy is an essential part of post-operative management and should address the whole of the kinetic chain, working on strength and control of the lower limbs to optimise balance and movement patterns in order to achieve the best results.