Modified technique for varus derotation osteotomy of the proximal femur in children.

Abstract

The results of a study in which the Richards' intermediate hip screw and the AO (Association for the Study of Internal Fixation (ASIF)) 908 fixed-angle blade plate were compared for use in proximal femoral osteotomy in children have previously been reported. In that study loss of position at the osteotomy site was reported as a specific complication associated with the use of the Richards' intermediate hip screw. The authors devised a simple modification of surgical technique using the Richards' intermediate hip screw to enhance the stability of the fixation. In the present article the results of a prospective study of that modified technique are reported and compared with the results of the previous study. During a 2-year period 24 proximal femoral osteotomies were performed on 12 children with cerebral palsy, using the modified technique by two surgeons. Only two of the 12 patients (16%) required postoperative immobilization in a hip spica cast. This represents a significant reduction in the level of spica casting when compared with the previous cohort study (61%). A simple modification of surgical technique improves the stability of fixation in proximal femoral osteotomy in children who have cerebral palsy. This resulted in a decreased need for supplementary hip spica casting and may reduce morbidity.