Comparing the efficacy of core decompression with autologous bone marrow mononuclear cell grafting with impacted bone grafting in treating bilateral femoral head necrosis

Objective To compare the efficacy of core decompression with autologous bone marrow mononuclear cell grafting with impacted bone grafting in treating bilateral femoral head necrosis. Methods From January 2011 to January 2017, a total of 44 patients with bilateral femoral head necrosis (88 hips) were admitted to the Department of Orthopaedics, China-Japan Friendship Hospital, including 35 males and 9 females with aged 34.9±7.2 years old (ranged from 22-48 years). Core decompression with autologous bone marrow mononuclear cell and impacted bone grafting were conducted to each hip joint for every patient. All patients were followed up for every 3 months at the first year postoperatively and for every 6 months thereafter. The following clinical measurement were recorded, Harris hip score (HHS), visual analogue score (VAS), the anterior-posterior and frog lateral radiographs, and CT. The 5-year survival rate of the hip was calculated with the endpoint event being defined as a need for total hip arthroplasty or other surgical intervention, or a HHS less than 70. Results The postoperative follow-up duration was 50.5±34.2 months in the impacted bone grafting group and 54.0±33.1 months in the core decompression with autologous bone marrow mononuclear cells group. Fifteen hips in the impacted bone grafting group and 13 hips in the core decompression with autologous bone marrow mononuclear cell group failed during the follow-up. The 5-year cumulative survival rates of the hips in two groups were 64.7% and 72.1%, respectively [HR=1.178, 95%CI(0.561, 2.477)]. In the impacted bone grafting group, the 5-year survival rates of the hip joints at the ARCO IIIB+IIIC and IIIA stages were 42.9% and 74.2%, respectively [HR=3.258, 95%CI(1.172, 9.059)]. In the core decompression with autologous bone marrow mononuclear cell group, the 5-year survival rates of hips at the ARCO stage I, II and IIIA stages were 50.0%, 75.3%, and 71.4%, respectively (χ2=0.757, P=0.685). Age, gender, BMI, preoperative HHS and etiology did not affect the effects of core decompression with autologous bone marrow mononuclear cell grafting or impacted bone grafting (P>0.05). The preoperative VAS of the impacted bone grafting group and the core decompression with autologous bone marrow mononuclear cell grafting group were 4.80±0.62 and 3.27±1.17, respectively (t=8.625, P<0.001). At the last follow-up, the VAS was reduced to 2.84±1.95 and 2.25±2.08, respectively (t=2.712, P=0.01; t=7.087, P<0.001) with significant difference in postoperative VAS between the two groups (t=2.489, P=0.017). The preoperative HHS of the impacted bone grafting group and the core decompression with autologous bone marrow mononuclear cell grafting group were 77.02±5.03 and 82.57±5.71, respectively (t=7.822, P<0.001). At the last follow-up, the HHS increased to 81.57±12.81 and 83.55±12.87, respectively. The difference between the preoperative and postoperative HHS was statistically significant in the impacted bone grafting group (t=2.389, P=0.021) but not in the core decompression with autologous bone marrow mononuclear cell grafting group (t=0.451, P=0.654). There was no significant difference in postoperative HHS between the two groups (t=1.353, P=0.183). Conclusion Both impacted bone grafting and core decompression with autologous bone marrow mononuclear cell grafting are safe and effective methods in treating femoral head necrosis. The ARCO stage is a risk factor affecting the prognosis of hips after impacted bone grafting, which has no effect on the mid-term survival of hips after core decompression with autologous bone marrow mononuclear cell grafting. Key words: Femur head necrosis; Bone transplantatio; Transplantation, autologous; Bone marrow transplantation