Technical particularities of joint preserving hip surgery in osteopetrosis.

Proximal femoral fracture and coxarthrosis are the most common orthopaedic problems of osteopetrosis. Fracture fixation is difficult and one-third fail, with total hip replacement as the final solution. There is little reported experience about how to deal with this particular type of bone and what has been published to date is surprisingly non-specific. Corrective osteotomies are mainly undertaken in children for non-union of a fractured femoral neck and/or for coxa vara. However, any information about technical problems and solutions is scarce and barely instructive. Osteotomy experience for osteopetrosis in youngsters and young adults has not been reported. Osteopetrosis bone is characterized by a small tolerance for displacement and by the high friction experienced when penetrating instruments and implants are used. This article describes the risks of hip surgery in the presence of osteopetrosis and also discusses osteotomies around the hip and how to limit any related complications. Four patients, who underwent different types of hip preservation procedure, have been used to illustrate the difficulties that can be encountered. The article also suggests ways to make osteotomies feasible in osteopetrosis bone, even in adults.