Avascular necrosis predictive factors after closed reduction in patients with developmental dysplasia of the hip

Sara Kheiri1, Mohammad Ali Tahririan1, Soheil Shahnaser1

  • 1Department of Orthopedic Surgery, Isfahan University of Medical Sciences, Isfahan, Iran.

Insights

Older age and wider abduction angles increase avascular necrosis (AVN) risk in developmental dysplasia of the hip (DDH) patients after closed reduction (CR). Younger patients and lower abduction angles (under 54°) improve outcomes.

Area of Science:

  • Orthopedic Surgery
  • Pediatric Orthopedics
  • Hip Dysplasia Research

Background:

  • Developmental dysplasia of the hip (DDH) is a prevalent pediatric orthopedic condition.
  • Closed reduction (CR) is a common conservative treatment for DDH with high success rates.
  • Avascular necrosis (AVN) is a significant complication following CR for DDH.

Purpose of the Study:

  • To identify risk factors for AVN after CR and Spica cast immobilization in DDH patients.
  • To determine the relationship between patient age, abduction angle, and AVN development.

Main Methods:

  • Retrospective observational study of 71 patients (89 hips) with DDH aged 6-24 months.
  • Follow-up for 3 years, documenting demographic data, Tönnis grade, pre-reduction procedures, and abduction angle.
  • AVN presence classified using the Bucholz and Ogden criteria.

Main Results:

  • 13 of 71 patients (18 hips) developed AVN.
  • Older age (mean 14.3 vs 12.2 months) and lower abduction angle (51.86° vs 58.46°) were associated with AVN.
  • Age over 12 months (OR=4.22) and abduction >54° (OR=34.88) significantly predicted AVN risk.

Conclusions:

  • Older age at intervention and larger abduction angles in Spica casts are predictors of AVN post-CR for DDH.
  • Performing CR at a younger age and maintaining abduction angles below 54° may improve prognosis.
Abstract