[General anatomy and image reconstruction analysis of the proximal femoral trabecular structures].

Objective: To investigate the three-dimensional structure of proximal femoral trabeculae, analyze the formation mechanism, and explore its relationship with the occurrence and treatment of proximal femoral fractures.

Methods: Six cadaver adult femur specimens were harvested and the gross specimens containing both trabecular system and cortical bone were established by hand scraping. All samples were scanned by micro-CT and the CT images were input into Mimics18.0 software to establish the digital proximal femoral model containing trabecular structure. The spatial distribution of trabecular system was observed, and the relations between trabecular bone and the proximal femur surface and related anatomical landmarks were analyzed in digital models.

Results: The gross specimen and digital models of trabecular system were successfully established. The trabecular system of proximal femur could be divided into two groups: the horizontal and vertical trabecular. The horizontal trabecular arose from the base of greater trochanter, gone along the direction of femoral neck, and terminated at the center of femoral head. The vertical trabecular began from the base of lesser trochanter and femoral calcar, gone radically upward, and reached the femoral head. The average distance of the horizontal trabecular to the greater trochanter was 22.66 mm (range, 17.3-26.8 mm). In the femoral head, the horizontal trabecula and the vertical trabecula were fused into a kind of sphere, and the distances from the horizontal trabecula to the surface of the femoral head vary in different sections. The average distance of trabecular ball to the femoral head surface was 6.88 mm (range, 6.3-7.2 mm) in sagittal plane, 6.32 mm (range, 5.8-7.6 mm) in coronal plane, and 6.30 mm (range, 5.6-6.3 mm) in cross section. The vertical and horizontal trabeculae intersect obliquely, and the average angle of horizontal trabecular and vertical one was 140.67° (range, 129-150°).

Conclusion: The trabecular system exhibits a unique spatial configuration, which is the main internal support of proximal femur. Restoration of the integrity of trabecular structure is the important goal of proximal femoral fractures.