Background:

Safe surgical dislocation has revolutionised hip preservation surgery by allowing complete access to the proximal femur while minimising the risk of avascular necrosis. However, despite meticulous technique, intraoperative injury to the superior retinacular vessels (SRV), the primary blood supply to the femoral head, can still occur, potentially compromising outcomes.

Purpose:

To identify, classify, and analyse intraoperative patterns and mechanisms of SRV injury during surgical hip dislocation procedures performed for complex hip deformities.

Methods:

A prospective analysis of all cases with intraoperative lateral retinacular damage during hip preservation surgeries through surgical dislocation between 2005 and 2024 was performed. Patient demographics, preoperative diagnoses, intraoperative findings, and patterns of SRV damage were documented. Standard safe surgical dislocation with trochanteric flip osteotomy was performed in all cases, with vascular assessment using arterial Dopplers and intraosseous femoral head drilling.

Results:

14 patients (mean age 14 years; 7 males, 7 females) were included. Preoperative diagnoses included Perthes disease, stable and unstable slipped capital femoral epiphysis (SCFE), healed SCFE, chondrolysis, and pseudo-rheumatoid dysplasia. Patterns of SRV injury included stripping of the lateral retinaculum during internal rotation in 3 cases, spontaneous avulsion in unstable slips and dysplastic hips, ischemia following distal neck osteotomies, and iatrogenic avulsion following combined flap elevation and circumferential cam osteoplasty. Pre-existing vascular compromise was common in unstable and healed slips. Careful surgical technique, controlled reduction, and intraoperative vascular monitoring minimised further SRV damage.

Conclusions:

This study represents the largest reported intraoperative series of SRV injuries during surgical hip dislocation. Internal rotation during reduction, osteotomy near the physeal scar, and extensive cam osteoplasty were major contributors to SRV injury. Awareness of vulnerable steps, meticulous surgical technique, and intraoperative assessment of femoral head perfusion are essential to preserve the femoral head's vascular integrity during complex hip preservation procedures.