Adding lateral retinacular release to medial patellofemoral ligament reconstruction reconstruction has no effect on...

To evaluate the effect of medial patellofemoral ligament (MPFL) reconstruction with or without lateral retinacular release (LRR) on patellar height in patients with recurrent patellar dislocation (RPD). It was hypothesised that the addition of LRR would not significantly modify patellar height compared with isolated MPFL reconstruction.

This prospective, single-blinded randomised controlled trial was conducted between 2011 and 2022. Patients aged 18-45 years with RPD were randomised into two groups: isolated MPFL reconstruction and MPFL reconstruction with associated LRR. Exclusion criteria included previous surgery on the same knee, concomitant bony procedures, or prior contralateral MPFL reconstruction. All patients were evaluated by blinded investigators. The primary outcome was patellar height measured by the Caton-Deschamps Index (CDI) on standardised lateral radiographs obtained at a minimum of 1 year after surgery.

Out of 140 enrolled patients, 107 completed the study, with 59 in the LRR group and 48 in the isolated MPFL group. The preoperative CDI was similar in both groups (1.32 [±0.168] in the LRR group and 1.29 [±0.163] in the isolated MPFL group), and postoperative CDI showed a significant decrease in patellar height in both groups (1.1 [±0.133] in the LRR group and 1.1 [±0.166] in the isolated MPFL group), with a mean follow-up of 12.5 ± 0.3 months, with no significant difference between them. A statistically significant reduction in CDI of 0.2 was observed in both groups.

Adding LRR to MPFL reconstruction has no effect on patellar height. Caton Deschamps Index demonstrated a mean decrease of 0.2 after MPFL reconstruction, with or without LRR.

Level II, low-powered randomised clinical trial.