Surgical treatment for developmental dysplasia of the hip- a single surgeon series of 47 hips with a 7 year mean follow up).

The treatment of developmental dysplasia of the hip (DDH) in children remains controversial. We describe the clinical and radiological outcomes of  47 hips in 43 children treated with open surgery by one surgeon between 2004 and 2008 for DDH. The mean age at operation was 25 months (5 to 113) with a mean follow up of  89 months  (22 to 169). At the latest follow up 40 of the 45 hips where Severin grades were recordable (89%) were graded as excellent or good, Severin class I or II. Clinically significant AVN (grade II to III  according to the Kalamchi and MacEwen classification) was seen in 6  (13%) of the hips. We found a pelvic osteotomy to be a risk factor for AVN  (p 0.02) and age at operation to be a risk factor for poor morphology at final follow up (p 0.03). Over 18 months old a pelvic osteotomy should be performed in selective cases depending on intra-operative stability, but we will now consider doing this as a staged procedure and delaying the osteotomy for a period of time after open reduction to reduce the risk of AVN.