Avascular osteonecrosis of the femoral head treated with a vascularized iliac bone graft: preliminary results and follow-up with radiography and MR imaging.

Treatment of avascular necrosis (AVN) of the femoral head with a vascularized iliac bone graft was studied in nine patients (12 hips). The condition of the femoral head was classified radiographically before and after surgery. Magnetic resonance (MR) imaging was performed to demonstrate the extent and signal intensity characteristics of the area of AVN and to assess the viability of the graft. The radiologic results were correlated with the clinical findings. Although radiography showed progression of disease in six patients, seven of the nine patients demonstrated clinical improvement. The MR imaging results correlated better with the clinical findings: MR imaging demonstrated progression of AVN in only two patients (two hips) and no progression or reduced necrosis in six patients (nine hips). Nine of the 11 grafts (eight patients) evaluated with MR imaging appeared viable after a mean follow-up of 50 months. MR imaging appears useful in assessing marrow changes and graft viability after treatment of AVN of the femoral head with a vascularized iliac bone graft.