Histopathological findings (Part 2) 120 days after injury (Results section: Histopathological findings). There is fatty degeneration in the injured area of the ICTs. The density of the collagen fibers is extremely low and they are not aligned in a unidirectional pattern. These fibers with their cells laid along them are immature and generally the characteristics of this tissue are similar to the fascia than the tendon (A). On the other hand, in the ITTs, the collagen implant was completely absorbed at 120 DPI. The collagen fibers have high density with an aligned direction in the line of stress between the muscle and calcaneus. No obvious degeneration is seen and the cellular and collagenic structures are highly matured (B) similar to the intact tendons (C). The gastrocnemius muscle in the injured control legs shows muscle atrophy with the newly regenerated granulation tissue around them, suggesting both the atrophy and fibrosis (D). No muscle atrophy or fibrosis are seen in the treated lesions (E) and the pattern of the muscle fibers is almost similar to the muscle of the intact legs (F) than the control ones (D) (H&E, Scale Bar =50 μm).