Histological appearance of the deep digital flexor tendon (DDFT) after complete transection of extensor tendons and partial transection of the superficial digital flexor tendon (SDFT).

Images A-C represents the non-operated controls (NOC), images D-F represent the DDFT following complete transection of the extensor tendons (TxEXT) and images G-I represent the DDFT following partial transection of the SDFT (TxSDFT). Images A,D and G are stained with haemotoxylin and eosin (H&E), images B, E and H are stained with picrosirius red (PR) viewed under polarised light and images C, F and I are stained with toluidine blue (TB). Increased cellularity and cellular rounding are represented by the black arrow. The white arrow represents a loss of normal coarse crimp and cocrimping indicative of alteration in collagen fibre alignment. The scale bar indicates 200μm.