Valgus extension osteotomy for 'hinge abduction' in Perthes' disease - Results at maturity and factors influencing the radiological outcome

Valgus extension osteotomy (VGEO) is a salvage procedure for 'hinge abducti on' in Perthes' disease. The indications for its use are pain and fixed def ormity. Our study shows the clinical results at maturity of VGEO carried ou t in 48 children (51 hips) and the factors which influence subsequent remod elling of the hip. After a mean follow-up of ten years, total hip replaceme nt has been carried out in four patients and arthrodesis in one, The averag e Iowa Hip Score in the remainder was 86 (54 to 100), Favourable remodellin g of the femoral head was seen in 12 hips. This was associated with three f actors at surgery; younger age (p = 0.009), the phase of reossification (p = 0.05) and an open triradiate cartilage (p = 0.0007). Our study has shown that, in the short term, VGEO relieves pain and corrects deformity; as grow th proceeds it may produce useful remodelling in this worst affected subgro up of children with Perthes' disease.