Effect of plasma rich in growth factors on the early phase of healing of surgically severed Achilles tendon in sheep: Histological study

Abstract

Tendon injuries are the most frequent musculoskeletal problems, constituting 30-50% of all sport-related lesions. Efficient handling of early stage tendon injury and healing can accelerate tendon repair as well as improve the quality of newly formed tendons. Plasma rich in growth factors (PRGF) is an autologous biological therapy that has been proposed to treat tendon injuries. To elucidate the effect of this treatment on the early stage of tendon healing, 14 sheep were used to perform the present study. The right Achilles tendon was surgically severed and repaired with sutures. Seven animals were treated with PRGF and the other seven with saline solution after surgical tendon reconstruction. Tendons were ultrasound-guide infiltrated 1 week after the induced injury. Two weeks later, the sheep were euthanized and histochemical and immunohistochemical analyses were performed. The tendons with PRGF showed reduced infiltration of inflammatory cells compared to those treated with saline solution. Analysis of the blood vessels, morphometric data of fibroblast nuclei, and collagen fibres in the extracellular matrix did not show statistical differences between groups. These findings suggest the important role that PRGF therapy plays in the modulation of inflammatory response in Achilles tendon injuries, leading to acceleration of the tendon healing process, shortening the convalescence period.