Is choice of approach associated with risk of avascular necrosis in pediatric septic hip?

Purpose: Septic arthritis of the hip in children and adolescents is a common condition requiring timely diagnosis and intervention. Surgical irrigation and debridement is typically performed through the anterior approach because of concerns about injury to the medial femoral circumflex artery leading to avascular necrosis. While there are multiple studies investigating the sequelae of anterior and medial approaches for reduction of developmental dislocation of the hip, none have compared these approaches for the pediatric septic hip. We hypothesize that there will be no significant difference in the rate of avascular necrosis when comparing the medial and anterior approaches to the septic hip in pediatric patients.

Methods: A retrospective review was performed of pediatric septic hips treated with irrigation and debridement through either a medial or anterior approach at a single institution over an 18-year period of time. The primary outcome measure was the development of avascular necrosis.

Results: Thirteen of 164 patients (7.9%) developed avascular necrosis. Avascular necrosis was noted in 9 of 101 patients who had anterior approach and 4 of 63 patients who underwent medial approach (p = 0.76). The average age for patients developing avascular necrosis was 10.0 years old versus 6.8 years old in patients who did not develop avascular necrosis (p = 0.01). The average follow-up was 3.3 years in patients with avascular necrosis versus 1.5 years for patients who did not develop avascular necrosis (p = 0.01).

Conclusion: Medial approach to the pediatric septic hip does not increase the rate of avascular necrosis compared to the anterior approach.

Level of evidence: Retrospective comparison study, Level III.