All animals were anesthetized by sevoflurane 250 mL (Sojourn, Piramal) via an inhaler. Following the induction of general anaesthesia, rats were placed in a supine position. First, approximately 1 mL of blood was taken from the rat tail artery and placed in the device for centrifugation at the appropriate speed for the preparation of PRF. The rat was then returned to the prone position. After longitudinal skin incisions, bilateral sciatic nerves were accessed via blunt dissection through the gluteus maximus and biceps femoris muscles. Bilateral sciatic nerves, from the sciatic notch to the bifurcation, were exposed. A 0.5-cm-long epineurium segment was circumferentially excised from the main nerve trunk to initiate scar tissue formation. For the right sciatic nerve, the incision was extended to the popliteal region, and approximately 10×10×0.5 mm3 (link)
 fat grafts were prepared from the adipose tissue in this area. Meanwhile, the fat graft obtained from the popliteal region was mixed with the PRF, whose centrifuge was finished and ready, and it was wrapped around the epineurectomy area. The left nerve segment did not undergo any surgical procedure other than the epineurectomy and was considered the sham (or control) group. The right sciatic nerve was considered the experimental (or treatment) group. For histopathological examinations, 12 randomly selected rats were euthanized in the fourth week for early results and the remaining 12 rats in the eighth week for late results.