Clinical significance of venous return disturbance in patients with osteonecrosis of femoral head / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To evaluate the correlation of venous return disturbance (VRD), bone marrow edema (BME) and the amount of joint fluid with clinical symptoms in osteonecrosis of the femoral head (ONFH).</p><p><b>METHODS</b>Twenty patients (25 hips) with ONFH proved by pathology were parallelly examined by 1.5 T MR and medullograph.</p><p><b>RESULT</b>In total 25 hips VRD was observed in 16 hips with medullograph and 13 hips with the clinical symptoms (P <0.05). BME was found in 17 with MRI (P <0.01), and the was found in 15 hips with MRI (Spearman=0.949). VRD were found in 16 hydrarthrus.</p><p><b>CONCLUSION</b>ONFH patients with clinical symptoms have VRD, BME and the hydrarthrus. The medullograph is of value in monitoring the development of ONFH.</p>

Relationships among magnetic resonance imaging, histological findings, and IGF-I in steroid-induced osteonecrosis of the femoral head in rabbits / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

<p><b>OBJECTIVE</b>To study the relationships among magnetic resonance imaging (MRI), histological findings, and insulin-like growth factor-I (IGF-I) in steroid-induced osteonecrosis of the femoral head in rabbits.</p><p><b>METHODS</b>Thirty rabbits were randomly divided into experimental Group A (n=15) and control Group B (n=15). The 7.5 mg/kg (2 ml) of dexamethasone (DEX) and physiological saline (2 ml) were injected into the right gluteus medius muscle twice at one-week intervals in animals of Groups A and B, respectively. At 4, 8 and 16 weeks after obtaining an MRI, the rabbits were sacrificed and the femoral head from one side was removed for histological study of lacunae empty of osteocytes, subchondral vessels, and size of fat cells under microscopy, and the femoral head from the other side was removed for enzyme-linked immunoadsorbent assay (ELISA) for IGF-I.</p><p><b>RESULTS</b>At 4, 8 and 16 weeks after treatment, no necrotic lesions were detected in Group B, while they were detected in Group A. Light microscopy revealed that the fat cells of the marrow cavity were enlarged, subchondral vessels were evidently decreased, and empty bone lacunae were clearly increased. The IGF-I levels in Group A were significantly higher than those in Group B. At 8 weeks after the DEX injection, the MRI of all 20 femora showed an inhomogeneous, low signal intensity area in the femoral head, and at 16 weeks, the findings of all 10 femora showed a specific "line-like sign". The MRI findings of all femora in Group B were normal.</p><p><b>CONCLUSION</b>MRI is a highly sensitive means of diagnosing early experimental osteonecrosis of the femoral head. However, the abnormal marrow tissues appeared later than 4 weeks when the expression of IGF-I increased. This reparative factor has an early and important role in response to steroid-induced osteonecrosis of the femoral head, and provides a theoretical foundation for understanding the pathology and designing new therapies.</p>