Background:Osteoporosis is a systemic skeletal disease characterized by decreased bone mass, destruction of the microarchitectonics of bone structure and a high risk for fracture
Objective:To explore in detail the structural characteristics of cancellous bone from the femoral head epiphysis of normal and ovariectomized rats, and to characterise an alternative and complementary anatomic site to improve experimental researches on osteoporosis.
Methods: Twenty female Sprague-Dawley rats were randomly divided into 2 groups:
Group: 1 (sham-operated control group) and group: 2 (bilaterally ovariectomized group OVX for induction of osteoporosis) group 2 is further divided into 2-subgroups:( 3-months OVX and 6-months OVX). Femur's heads were collected, examined by using different techniques such as scanning electron microscopy (SEM), energy‐dispersive X‐ray spectroscopy (EDX) and routine bone histology. Blood serum samples were collected for the determination of total calcium and phosphorus levels by using a spectrophotometer.
Results:Postmenopausal osteoporosis model was successfully established in OVX rat compared to sham-operated control rats. The femoral head epiphysis of OVX animals had decreased trabecular thickness, cortical thickness, with increased medullary width and porosity holes as determined by histological assessment and SEM. Moreover, EDX analysis of the femoral head epiphysis indicated a significant decrease of calcium concentration in epiphyseal regions of femoral heads in OVX rats (P<0.05) compared to sham-operated control rats. In contrast, serum levels of calcium in sham-operated group were significantly decreased compared to that of OVX 3 or 6 months groups (P<0.05).
 Conclusion: The data from this study characterize osteoporosis induced in the rat 12 weeks after ovariectomy and present the epiphysial femur's head as a site for further investigations on osteoporosis and osteoarthritis.