**4. Principles of treatment of patellofemoral instability**

## **4.1 Nonoperative treatment**

Based on our extensive clinical experience (level V evidence), we have found that nonoperative treatment of chronic patellar dislocations (treated initially by a period of brief immobilization followed by rehabilitation) has produced less satisfactory or even dismal results, with nearly half of patients having recurrent dislocations or continued knee symptoms. Steiner and Parker [30] have also reported less satisfactory clinical outcomes following nonoperative treatment of patients with chronic patellofemoral instability. We believe that immobilization for patients with recurrent episodes of patellar dislocation may be used in the short-term for patient comfort; however, it is of little benefit in the long-term. A trial of rehabilitation may be offered to a patient who experiences only occasional dislocation and displays no obvious predisposing anatomic or radiographic abnormalities [30]. Rehabilitation may be augmented by the use of a patellar brace or orthosis if tolerated by the patient. On the other hand, patients who have predisposing anatomical risk factors (**Table 1**) or those who experience recurrent patellar dislocation with activities of daily living will likely require operative treatment.
