Surgical treatment of femoral bending deformity in a patient with vitamin D-resistant rickets

摘要

Surgical treatment of patients with vitamin D-resistant rickets is reserved for management of severe deformities or pathological fractures of the lower limbs. This case report describes the operative management of a child with vitamin D-resistant rickets suffering from a pathological fracture and a bending deformity of the right femoral bone. A modified technique of fragmentation and realignment by intramedullary fixation was performed using an unreamed humerus nail. We corrected the anatomical proximal femoral shaft angle (aMPFA) from 68° to 84° and achieved three more centimetres of femoral length. The same procedure was performed on the left femur and corrected the aMPFA from 108° to 89° and gained 2.5 more centimetres of femoral length. Thus the legs were almost equal in length. We preferred the modified technique of multiple osteotomies and intramedullary fixation by nailing (originally described by Sofield and Millar) because the correction of angulation and rotation of the femoral shaft in one step appeared to be much easier than with plate fixation. Moreover, this method seems to reduce the number of refractures and enables the patients to approach the normal activities of growing children.