ObjectiveTo compare the effectiveness of sequestrum clearance and impacting bone graft via surgical hip dislocation approach and core decompression and bone graft for avascular necrosis of the femoral head (ANFH) at Association Research Circulation Osseous (ARCO) stage Ⅲ.MethodsA clinical data of 60 patients (69 hips) of non-traumatic ANFH at ARCO stage Ⅲ, which met the inclusion criteria between October 2013 and April 2016, was retrospectively analyzed. Among them, 24 patients (28 hips) were treated with sequestrum clearance and impacting bone graft via surgical hip dislocation approach (group A); and 36 patients (41 hips) were treated with core decompression, sequestrum clearance, impacting bone graft, and nonvascular fibular allograft supporting (group B). There was no significant difference in gender, age, disease duration, affected side, type and stage of the ANFH, and preoperative Harris hip score and visual analogue scale (VAS) score between the two groups (P>0.05). After operation, the function of the hip was evaluated by Harris hip score, imaging examination was performed to observe the femoral head shape and evaluate whether the hip preserving success.ResultsThe incisions of two groups healed by first intention. All patients were followed up. The follow-up time was 12-48 month (mean, 25.8 months) in group A and 12-54 months (mean, 26.4 months) in group B. At last follow-up, 5 hips in group A were classified as clinical failure, femoral head survival rate was 82.1%, the median survival time was 43 months. While 19 hips in group B were classified as clinical failure, femoral head survival rate was 53.7%, the median survival time was 42 months. There was significant difference in survival curve distribution between the two groups (χ2= 4.123, P=0.042), and the surgical procedures of group A was superior to group B. In the two groups, the Harris hip scores at last follow-up were significantly higher than preoperative ones (P<0.05), and VAS scores were significantly lower than preoperative ones (P<0.05). There was no significant difference in Harris hip score and VAS score at last follow-up between the two groups (P>0.05). All grafted bones got fusion according to the X-ray films, and there was no significant difference in the fusion time between the two groups (t=0.752, P=0.456). In group A, greater trochanter bone cutting were healed well; and the heterotopic ossification around the hip joint occurred in 1 case.ConclusionThe surgery of impacting bone graft via surgical hip dislocation approach and core decompression and bone graft can be applied to treat ANFH at ARCO stage ⅢA which was mild collapse and satisfactory effectiveness can be obtained. While for the patients of ANFH at ARCO stage Ⅲ B with severe collapse, the hip survival rate of the former is better than that of the latter.