# Soft Tissue Surgical Technique for Obligate Dislocation of the Patella

## TL;DR

A new soft tissue surgical technique is described for treating patellar dislocation in children, improving mobility and stability.

## Contribution

A combined soft tissue surgical approach is introduced for treating patellar dislocation in skeletally immature patients.

## Key findings

- Both patients achieved full weight-bearing without dislocation after surgery.
- Patient 1 regained the ability to play sports with a 165° range of motion.
- Patient 2 gained stability and improved knee motion to 160°.

## Abstract

Obligate dislocation of the patella (ODP) is a subtype of congenital disorders and dislocations of the patella. Severity of the condition varies; symptoms range from minor disabilities to impaired ambulation. Definitive treatment for ODP is surgery, with the choice of surgical procedure determined by skeletal maturity.

This report documents a soft tissue surgical correction for 2 patients with ODP using (1) lateral release of the retinaculum, (2) Z-lengthening of the quadriceps tendon, (3) patellar tendon split transfer (medial side only), and (4) vastus medialis oblique muscle advancement. Patient 1 is a 7-year-old skeletally immature male who experienced complete lateral dislocation of the right patella with flexion. The patient was unable to play sports without falling and without constant patellar dislocation. Patient 2 is a 7-year-old skeletally immature male with Down syndrome who presented with a right laterally dislocating patella with flexion and a 15° flexion contracture of the knee. The patient was unable to ambulate and—according to his parent—would “hit the side of his patella” to center it on his knee to provide stability and permit weight-bearing in a standing frame. After surgery and recovery, both patients reached full weight-bearing without dislocation. Patient 1 plays sports for the first time and has a range of motion of 165°. Patient 2 can stand with stability, continues to work on gait training, and has a range of motion of 160°.

This combined surgical approach mitigates patellar tilt, knee flexion contracture, and recurrent instability, offering a reproducible option for improving stability, tracking, and long-term function in complex patellofemoral pathology.