Relationships among magnetic resonance imaging, histological findings, and IGF-I in steroid-induced osteonecrosis of the femoral head in rabbits
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.
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.
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.
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.
Key wordsDexamethasone (DEX) Insulin-like growth factor-I (IGF-I) Magnetic resonance imaging (MRI) Osteonecrosis of the femoral head Pathology
- Cheng, M.Z., Simon, C.F., Rawlinsine, A.A., 2002. Human osteoblast proliferative responses to strain and 17beta2 estrodiol are mediated by the estrogen receptor and the receptor for lnsulin-like growth factor I. J. Bone Miner. Res., 17(4):593–602. [doi:10.1359/jbmr.2002.17.4.593]PubMedCrossRefGoogle Scholar
- Gelato, M.C., Vassalotti, J., Spatola, E., Carlson, H.E., Rulherford, C., Marsh, K., 1991. Differential tissue regulation of the insulin-like growth factors in rats bearing the MStT/W15 pituitary tumor. Neuroendocrinology, 561(6): 765–774.Google Scholar
- Hawker, F.H., Stewart, P.M., Baxter, R.C., Borkmann, M., Tan, K., 1987. Relationship of somatomedin-C/1 insulin-like growth factor I levels to conventional nutritional indices in critically ill patients. Crit. Care Med., 15(8): 732–736. [doi:10.1097/00003246-198708000-00004]PubMedCrossRefGoogle Scholar
- Miyanishi, K., Yamamoto, T., Irisa, T., Yamashita, A., Jingushi, S., Noguchi, Y., Iwamoto, Y., 2001. A high LDL/HDL cholesterol ratio as a potential risk factor for corticosteroid-induced osteonecrosis in rabbits. Rheumatology, 40(2):196–201. [doi:10.1093/rheumatology/40.2.196]PubMedCrossRefGoogle Scholar
- Miyanishi, K., Yamamoto, T., Irisa, T., Yamashita, A., Jingushi, S., Noguchi, Y., Iwamoto, Y., 2002. Bone marrow fat cell enlargement and a rise in intraosseous pressure in steroid-treated rabbits with osteonecrosis. Bone, 30(1): 185–190. [doi:10.1016/S8756-3282(01)00663-9]PubMedCrossRefGoogle Scholar
- Ross, R., Miell, J., Freeman, E., Jones, J., Matthew, D., Buchanan, C., 1991. Critically ill patients have high basal growth hormone levels with attenuated oscillatory activity associated with low levels of insulin-like growth factor-I. Clin. Endocrinol. (Oxf.), 35(1):47–54. [doi:10.1111/j.1365-2265.1991.tb03495.x]CrossRefGoogle Scholar
- Sakaia, T., Suganoa, N., Tsuji, T., Nishii, T., Yoshikawa, H., Ohzono, K., 2000. Serial magnetic resonance imaging in a non-traumatic rabbit osteonecrosis model: an experimental longitudinal study. Magnetic Resonance Imaging, 18(7):897–905. [doi:10.1016/S0730-725X(00)00175-2]PubMedCrossRefGoogle Scholar
- Vande, B.C., Malghem, J., Lecouvet, F.E., Jamart, J., Maldague, B., 1999. Idiopathic bone marrow edema lesions of the femoral head: predictive value of MR imaging findings. Radiology, 212(2):527–535.Google Scholar
- Vande, B.E., Malghem, J.J., Labaisse, M.A., 1993. MR imaging of avascular necrosis and transient marrow edema of the femoral head. Radiographics, 13:501–520.Google Scholar
- Vande Berg, B., Gilon, R., Malghem, J., Lecouvet, F., Depresseux, G., Houssiau, F., 2006. Correlation between baseline femoral neck marrow status and the development of femoral head osteonecrosis in corticosteroid-treated patients: a longitudinal study by MR imaging. Eur. J. Radiol., 58(3):444–449. [doi:10.1016/j.ejrad.2006.01.009]CrossRefGoogle Scholar