Avascular necrosis rate in early reduction after failed Pavlik harness treatment of developmental dysplasia of the hip

Our hypothesis is that hips with developmental dysplasia (DDH), which fail Pavlik harness treatment and are reduced within 3 months of age, have a low rate of avascular necrosis (AVN). Inclusion criteria are as follows: diagnosis of DDH within 2 months of birth, failure of reduction or stabilization by Pavlik harness treatment, surgical reduction of the hip advised to be performed within 3 months of age, and follow-up for Salter criteria of AVN. Twenty-one consecutive cases (35 hips) met the inclusion criteria. Nineteen cases (31 hips) were initially reduced within 3 months of age, and none of these cases developed AVN. After Pavlik harness failure, initial closed reduction was achieved in 33 (94%) of 35 hips, and open reduction required in 2 (6%) of 35 hips. At latest follow-up, one (3%) of 35 hips had AVN. At the time of reporting, 1 (3%) of the 35 hips has required an additional procedure (Pemberton osteotomy) for residual dysplasia. There were 2 outlier cases (4 hips) in which the parents delayed the reduction and 1 case developed unilateral AVN, which was reduced after the proximal femoral ossification center developed at 7 months of age. The data presented in the current study support our hypothesis.