Several risk factors for the development of osteonecrosis of the femoral head following treatment of developmental dislocated hip have been reported. The need for further research with a large-enough sample size including statistical adjustment of confounders was demanded. The purpose of the present study was to find reliable predictors of osteonecrosis in patients managed for developmental dislocation of the hip and to evaluate if delayed treatment increased the risk of residual acetabular dysplasia requiring secondary surgeries.

Inclusion Criteria:

• Follow-up > 3 years

Exclusion Criteria:

• teratological hip dislocation
• neuromuscular disease
• previous open reduction at another medical institution

Consecutive series of patients hospitalized because of developmental dislocated hip between 1198 and February 2007