The results of hip reconstruction surgery are known for non-walking (GMFCS IV and V) and walking (GMFCS I and II) patients. Few studies deal with GMFCS III patients in isolation. Their intermediate functional status can be deteriorated by asymmetrical contractures, hip dislocation, multi-level deformities of the lower limbs, leading to motor function degradation, and possibly losing their ability to walk. The aim of our study was to establish whether surgical results were maintained over time and whether the functional status changed.

Fifteen patients with GMFCS III spastic diplegia, treated for hip subluxation, were reviewed. The mean age at the time of surgery was 10 years old. The mean follow-up after surgery was 11 years. Reconstructive surgery was performed on 21 hips including pelvic osteotomy in all cases, with associated femoral osteotomy in 19 cases. Clinical (pain, joint mobility, walking aids, walking distance, GMFCS level) and radiological data (Melbourne Cerebral Palsy Hip Classification, standard coxometry) were recorded preoperatively and at the last follow-up.

Preoperatively, 6 patients were losing their ability to walk due to pain and flexion-adduction contracture. At the last follow-up, no patients had pain and joint mobility was improved in all cases. For one patient, recovery to their previous functional state required a period of two years. In the long term, 14 patients were GMFCS III and only one patient was GMFCS IV due to reasons unrelated to hip surgery. The radiological parameters improved significantly. The Melbourne score was IV preoperatively for all patients. At the last follow-up, 10 hips were grade I, 6 hips were grade II and 5 hips were grade III.

Correction of architectural disorders of the subluxed hip by pelvic osteotomy, in most cases associated with femoral osteotomy, improves functional and radiological status for GMFCS III patients. This improvement is maintained in the long-term. Complementary surgeries correcting the other deformities of the lower limbs were necessary in more than half of the patients.

IV.