Non-operative Treatment in First-time Patellar Dislocation

Study to evaluate the conservative treatment of patients after their first episode of primary lateral patellar dislocation. Randomized controlled trial with 2 groups: standard treatment (2-weeks with brace) followed by physical therapy, compared with knee taping and physical therapy. 1-year follow-up. Measurements include physical exam, radiographs and MRI. Outcomes: recurrence, lateral patellar tilt, functional scores, apprehension, pain. Hypothesis: less recurrence in the knee taping group, as well as better functional scores.

Patients between 10-40 years old with first patellar dislocation are invited to participate in this conservative treatment study. Patients are excluded if they have bilateral acute patellar dislocation, previous surgeries in the affected knee, osteochondral fracture, open patellar dislocation. This is a randomized controlled trial with four groups of treatment: Standard treatment (2-weeks with a knee brace) and physical therapy Knee taping and physical therapy (1-week with knee brace) Sample size: 50 patients / knees Outcomes of interest: recurrence in patellar dislocation, functional scores (Banff, Norwich), return to sport, patellar tilt

Patients are randomized either to standard care or in the intervention group. Standard care patients are treated with knee brace (2 weeks) and physical therapy. In the intervention group: they receive knee taping with knee brace during 1-week.

The investigator and outcomes assessor will not have access to the type of treatment a patient received.

The patient is treated with tape in special configuration (McConell modified) for the patella + standard care

Patellofemoral instability specific score to assess function (disease-specific). The punctuation range is between 0-100 points. The best health scenario is 100% and the worst is 0.

Patellofemoral instability specific score to assess function (disease-specific). The punctuation range is between 0-100%. The worst health deficit is 100% and the best is 0%.

Patellar apprehension test during physical examination. The quadriceps should be relaxed to allow passive movements of the patella. The clinician will perform this technique by using their thumb of both hands, and pressing on the medial side of the patient's patella. The test is positive if it produces pain and apprehension.

J sign during physical examination. The J-sign refers to the inverted 'J' track the patella takes from extension to early flexion. The J-sign is a clinical finding indicative of patellar maltracking.

Percentage of the patients that were able to return to do their usual sport after the initial injury (patellar dislocation)

Inclusion Criteria: - Patients with first episode of acute lateral patellar dislocation during the last 7 days. Exclusion Criteria: * Patients with acute bilateral patellar dislocation. Patients with open patellar dislocation. Patients with previous knee surgery in the same knee.

Data will be shared if it is found to be relevant for understanding better the study or the analysis. This includes the journal where the paper is submitted and investigators with interest in the study.