Inclusion Criteria:  Diagnosis of recurrent patellar instability (≥ 2 episodes) at the time of surgery Indications for patellar stabilization surgery Availability of X-rays in digital format Patients who do not meet the inclusion criteria  Exclusion Criteria:  Clinical history of <2 patella dislocations Non-availability of X-rays in digital format Not indicated for patellar stabilization surgery Contraindications to surgery Patients with osteoarthritis