Age-Related Effects on Right Femoral Bone of Male Wistar Rats: A Morphometric and Biomechanical Study

Introduction Study of the variations of bone characteristics with age in different animal models is important to design musculoskeletal studies. Thus, this study aimed to evaluate the bone mass, dimensions, and biomechanical parameters of the femur in young, middle-aged, and aged Wistar rats. Materials and Methods Thirty male rats ( Rattus norvegicus ) were divided in three groups ( n = 10 per group)-3-month-old young rats, 12-month-old middle-aged rats, and 18-months-old aged rats. The right femurs were subjected sequentially to morphometric study (bone weight, cortical thickness) and biomechanical tests (maximum resistance strength and bone stiffness). Results We observed a significant increase in femur histological (cortical thickness) and biomechanical (maximum strength and bone stiffness) parameters with aging when compared with young animals. Conclusions With the advancing age, the right femoral bone of middle-aged and old animals had greater variations when compared with young animals. However, further studies with the aid of a comparison between right and left femur and other long bones in both male and female rats are needed to corroborate with our findings.