Clinical Application of Proton MR Spectroscopy of the Femoral Head in Patients with Osteonecrosis

In avascular necrosis of the femoral head, microscopic morphologic changes usually include increased fatty content, which elevates intraosseous pressure and further impairs blood perfusion within the femoral head. Magnetic resonance images show a characteristic morphologic in the mummified fat as well as the edematous bone marrow. Proton magnetic resonance spectroscopy, an advanced technique, can be used measure the lipid and water components within bone marrow in the lumbar spine. Because its usefulness in the evaluation of the femoral head has been demonstrated, we applied the proton magnetic resonance spectroscopy to evaluate both the avascular femoral head of patients with osteonecrosis and the intact femoral heads of healthy volunteers. Our results revealed a significant difference between these two groups in terms of the lipid and water components of the femoral heads. In conclusion, proton magnetic resonance spectroscopy of lipid and water contents is useful in the evaluation of bone marrow of the avascular femoral head. Further study with histologic proof is indicated.