Figure 1. Micro-CT analysis, histological evaluation, and SEM analysis of femoral heads in control and SAON groups.

A: In control group, femoral heads were properly shaped, with no evidence of cortical bone collapse, and trabecular bone was uniform, dense, continuous, and of normal thickness. In SAON group, femoral heads showed changes in shape, with evidence of cortical bone partial collapse, trabecular fracture, trabecular sparseness, thinning, and increased intercellular spacing. B: Micro-CT evaluation of control and SAON groups. All data are presented as mean±SD (n=6). *: P<0.05, **:P<0.01, vs. control group. BMD: Bone mineral density; BV/TV: Bone tissue volume fraction; BS/BV: Bone surface/volume ratio; Tb. N: Trabecular number; Tb. Th: Trabecular thickness; Tb. Sp: Trabecular separation. C, D: In control group, bone trabeculae were dense and intact, rich in bone marrow cells, and contained only a few fused adipose cells. In SAON group, trabecular bone displayed a disordered structure that appeared thinner and sparser, showed partial fractures, and contained adipose cells that were fused into vacuoles; bone trabeculae in SAON group contained more empty lacunae when compared to those in control group. E, F: In control group, bone trabeculae were dense, trabecular spacing was small (at low magnification), trabecular surface was smooth, and there were dense bone fibers (at high magnification). G–J: In SAON group, bone trabeculae were sparser, trabecular spacing was increased (at low magnification), and trabecular bone surface was disordered (at high magnification).