Background: Osteonecrosis of the femoral head is a deficiency of blood supply resulting in femoral head collapse and joint destruction. This usually found in young adults as the leading cause of hip arthroplasty. Core decompression has been reported to reduce the bone marrow pressure for treatment of stage I and II of disease. Later, addition of concentrated bone marrow injection was proposed and reported good result. The purpose of the present study was to report the result of core decompression and concentrated bone marrow injection.
Material and Method: Twelve patients with osteonecrosis of femoral head underwent a core decompression and concentrated autologous bone marrow injection. Data of age, sex, underlying disease, risk of osteonecrosis were collected. Patients were followed at 3 months, 6 months, 1 year and then yearly. Radiographic data were recorded.
Results: Thirteen hips in 12 patients underwent the procedure. Two cases were excluded due to loss of follow-up. Mean age was 36.2 (12-56). One hip were in stage I, five in stage II and five in stage III. Risk factor included steroid usage in 6 hips and alcohol consumption in 3 hips. Underlying diseases were SLE (5), dermatitis (1), post-traumatic (1). Average nucleated cell from marrow was 91.58 x 106/ml (+ 55.9). CD34 was 17.25 x 106/ml cells and percentage of recovery of mononuclear cell was 70.4%. Mean follow-up time was 3.6 years (range 1-7 years). All cases had good pain relief initially. At the last followup 8 hips (72%) had progression and 2 underwent surgery. No infection occurred. No adverse effect detected.
Conclusion: This report showed low success rate of core decompression with concentrated autologous bone marrow grafting. The effect of delayed progression is not clear. However, the procedure appeared to be safe without immediate complication.

Keywords: Osteonecrosis, Core decompression, Autologous bone marrow, Femoral head