Fifty-two iliopsoas transfers were performed in twenty-eight children from a clinic population of 150 myelomeningocele patients. All the patients operated on had neurological deficits characterized by muscle imbalance around the hip, that is, hip flexors and adductors overpowering all the other muscles.

The neuromuscular function of these children varied considerably. It was of the utmost importance to evaluate function at birth and on repeated examinations thereafter. These evaluations permitted a prediction of future functional achievement, and detection of muscle imbalances so that the development of deformity could be anticipated and the need for treatment could be established. Muscle imbalance at the hip if left untreated led to deformities in subsequent years that made walking difficult or impossible. These deformities included lumbar lordosis, hip-flexion deformity, subluxation, and dislocation of the hip.

Transfer of the iliopsoas muscle to the posterolateral aspect of the greater trochanter was employed to correct the muscle imbalance occurring when the strength of the hip adductors and flexors overpowered their antagonists. The method of transfer used was a modification of that described by Mustard for paralysis due to poliomyelitis.

Complications were one wound infection which cleared with no residua, fourteen fractures of the femur and tibia in six patients after the plaster casts were removed, limitation of hip motion seen in four hips of three patients, and three dislocations in two patients. Improvement was seen in all but seven of the fifty-two hips treated. These seven had limitation of motion on the dislocation was not reduced.