Core decompression in combination with nano-hydroxyapatite/polyamide 66 rod for the treatment of osteonecrosis of the femoral head

The aim of this study was to investigate the effectiveness of core decompression in combination with a nano-hydroxyapatite/polyamide 66 (n-HA/PA66) rod and a porous bioglass bone graft for the treatment of osteonecrosis of the femoral head (ONFH). Sixty-four patients (84 hips) with ONFH were allocated to a program of either core decompression (CD) in combination with a n-HA/PA66 rod and a porous bioglass bone graft (treatment group) or CD with an autologous cancellous bone graft (control group). Clinical and radiographic retrospective follow-ups were performed on all patients with the prospectively collected data. The overall clinical failure rate in the treatment group (9/38, 23.68 %) was lower than that of the control group (24/46, 52.17 %) (p < 0.05). Harris hip scores (HHS) were significantly increased in both groups post-surgery (p < 0.05). There was a significant difference between the two groups on HHS improvement for Steinberg IIC and IIIA (p < 0.05 and p < 0.001, respectively). The visual analogue scale (VAS) was significantly decreased in both groups post-surgery (p < 0.05). Especially, significant difference in the VAS improvement was observed between the groups for IIB, IIC and IIIA (p < 0.05, p < 0.05 and p < 0.01, respectively). Core decompression combined with the implantation of a n-HA/PA66 rod and a bioglass bone graft can significantly decrease hip pain, improve hip function, and prevent the collapse of the femoral head in patients with ONFH. As the effectiveness of this approach appears to vary with Steinberg stage, we suggest that this treatment procedure may be suitable for patients with early to middle stage ONFH.