Gross pathology: A) Injured tendon of a rabbit of 28 DPI showing swelling, hyperemia and peritendinous adhesion. It is much thicker than the normal contralateral tendon. B) Normal tendon of a 28 DPI rabbit having shiny and normal appearance. C) Injured tendon of 84 DPI group. The hyperemia has disappeared, the tendon diameter is slightly reduced and no adhesion is seen in the peritendinous area D) Normal tendon of a rabbit of the 84 DPI group.