Fig. 3.

Disc injury leads to progressive fibrofatty degeneration of paraspinal muscle. (A-B) Representative Masson trichrome stains of proximal and distal muscle segments from DI and sham mice at 6 weeks and (C-D) 15 weeks. (E-F) Fibrosis Index calculated at 6 weeks and 15 weeks using ImageJ (n = 3–4 mice/group at 6 weeks, n = 3 mice/group at 15 weeks; 10x magnification; scale bar = 150μm). (G-H) Representative Oil red-O stains of DI and Sham mice at 6 weeks and (I-J) 15 weeks. Fat Index calculated at 6 weeks and 15 weeks using ImageJ (n = 3–4 mice/group at 6 weeks, n = 3 mice/group at 15 weeks; 10x magnification; scale bar = 150 μm). T-tests were performed between corresponding DI and sham muscle segments as well as and proximal and distal segments of within group; bar indicates p < 0.05.