Fig. 4

Histomorphometric analysis of grafted extensor digitorum longus muscles. a Total number of muscle fibres and b number of small, centrally nucleated, embryonic MyHC+ (regenerating) muscle fibres in sham-operated muscles at day 1 or in grafted EDL muscles at various times after grafting, expressed as number of muscle fibres per transverse section. WT, wild-type; KO, osteopontin-null. Data are presented as mean ± s.e.m. in n = 6 animals from each group at each time point. Data were analysed using one-way ANOVA with Tukey’s multiple comparison test. *p < 0.5, **p < 0.01 and ***p < 0.001. c Frequency histograms of minimum Ferret’s diameter of muscle fibres from autografted and cross-grafted muscles 3, 5, 7 and 14 days after surgery