The clinical and radiological effectiveness of autologous bone marrow derived osteoblasts (ABMDO) in the management of avascular necrosis of femoral head (ANFH) in sickle cell disease (SCD).

purposeAvascular necrosis of the femoral head is a common issue faced by orthopaedic surgeons that ranges between 10 and 18%, but in patients with SCD, the incidence reaches 30%. There is no definite treatment except joint arthroplasty. Regenerative medicine is an option to cure or delay joint arthroplasty. We report here our experience with the injection of ABMDO to manage ANFH and report our medium-term results, the progression of the ANFH if any and the delay in total hip arthroplasty. (THA).

methodsSixty-Three (63) patients with SCD and ANFH were examined and thoroughly investigated, and those who had ANFH < grade II were consented to receive ABMDO. Patients were clinically assessed preoperatively using the Visual analogue scale (VAS), Modified Harris Hips Score (MHHS) and Azam-Sadat Score (ASS) for Quality of Life Score for Chronic Hip Disease. Ten millilitres of bone marrow were aspirated under local anaesthesia and placed in 20 CC of culture media. Osteoblasts were cultured from the aspirated bone marrow. Under anaesthesia, the osteonecrosed lesion was drilled using a 3-mm cannulated drill, and 5 million osteoblasts were injected at the lesion site. Patients were evaluated in the outpatient clinic after 2 weeks. At 4 months, a repeat MRI was done, and patients were followed for a minimum of 2 years.

resultsThe average age of patients was 25.93 ± 5.48 years. There were 41 (65%) females and 22 (35%) males. The mean hemoglobin S was 83.2 ± 5.1%. The average follow-up was 49.05 ± 12.9 (range: 24-60) months. TheVAS significantly improved from 7.79 ± 1.06 initially to 4.07 ± 1.08 (p < 0.0001) at 2 weeks and continued to improve for the next 24 months, when it was 2.38 ± 0.55 (p < 0.0001). The MHHS improved from 41.77 ± 5.37 initially to 73.19 ± 6.48 at 4 months (p < 0.001), and at 24 months, it was 88.93 ± 3.6 (p < 0.001). The ASS also significantly improved from 2.76 ± 0.49 preoperatively to 7.92 ± 0.09 (p < 0.0001) at 24 months. A comparison of the MRI's from before and after the osteoblast implantation revealed new bone formation and amelioration of the avascular lesions. Three patients were unsatisfied with their outcomes. and one patient suffered a repeat attack of the vaso-occlusive crisis within 6 months of the osteoblast injection.

conclusionsThe results give credence to our earlier short follow-up results showing that osteoblast transplantation has great potential in the healing of avascular lesions. Our study fits the criteria of a Phase II clinical trial, and we believe a larger study equivalent to Phase III numbers should be conducted and include patients with not only SCD but also steroid-induced and idiopathic avascular necrosis. LEVEL OF EVIDENCE: II.