Fig. 2

Hematoxylin and eosin (H&E) staining of quadriceps muscle, patellar tendon, collateral ligaments, articular cartilage, and infra- and suprapatellar fat pads. H&E staining shows the fatty infiltration in the vitamin D-deficient (VDDef), vitamin D-sufficient (VDSuff), and vitamin D-supplemented (VDSupp) groups: quadriceps muscle (a, b, c), patellar tendon (d, e, f), and collateral ligaments (g, h, i). Chondrocyte clustering (×40 original magnification) in the VDDef and VDSuff groups compared with the VDSupp group (j, k, l), as well as the adipocyte area in infrapatellar (m, n, o) and suprapatellar fat pads (p, q, r), is shown. The percentage of fatty infiltration per high-power field (s), average total and clustered chondrocytes (t), and average adipocyte area (u) are graphed. Arrows indicate the presence of adipocytes within the matrix of the tissue and chondrocyte clustering. These are the representative images of five swine each in the VDDef and VDSuff groups and three swine in the VDSupp group. Data are shown as mean ± SD. *p < 0.05, **p < 0.01