Subtrochanteric shortening osteotomy in adult sickle cell disease patients with cemented total hip arthroplasty for hip deformities secondary to childhood osteonecrosis: is healing a challenge?

Abstract

Purpose: Hip deformity is frequent after childhood osteonecrosis in patients with sickle cell disease (SCD). When they are adults, they present a challenge as candidates for total hip arthroplasty (THA) because of abnormal bone development, their relative youth, and also because of their disease. Performing subtrochanteric osteotomy associated with THA is technically challenging, and healing of osteotomies has never been reported in this population with frequent osteonecrotic bone, whether using cemented or uncemented arthroplasties.

Methods: We retrospectively analyzed 59 cemented THA with femoral corrective osteotomies (subtrochanteric shortening and transverse derotational osteotomy) performed on hip deformities between 1984 and 2018 in 59 sickle cell adult patients. The patient's age at the onset of osteonecrosis was an average of 8.4 years (6 to 10 years), and at the time of the THA was 28.6 years (19 to 41 years). All the patients had a minimum followup period of six years. Endocrinopathy was frequently associated to SCD Data and consequences were evaluated on bone union. The mechanical variables, such as the length of the resected femur, limb lengthening, the location of the osteotomy site, the size of the stem bridging the osteotomy, and any complications, were also analyzed.

Results: The average length of the resected femoral segment was 38.4 mm. The length of the femoral stem (bridging the osteotomy) was average 13 cm. The mean osteotomy union time was 10.6 months. Twenty-four osteotomies healed in six months, six in nine months, and 29 in twelve months, while five required bone grafts at nine months. The union time of the osteotomy was average 10.6 months. Complications included four cases of transient nerve palsy, and five intraoperative femur perforations. No statistically significant relationship was found between osteotomy union time and mechanical variables. The severity of endocrinopathy associated with sickle cell disease prolonged the healing time. In three cases, cement leakage into the osteotomy gap occurred without resulting in non-healing.

Conclusion: Cemented THA, combined with a subtrochanteric femoral shortening with transverse derotational osteotomy, has a long union time but is effective for adult hip deformities of patients with sickle cell patients.