Histopathological Changes Following Administration of Platelet-rich Plasma (PRP) in Femoral Head Osteotomy (FHO) in Rabbit

BACKGROUND: Femoral head osteotomy in cases of fractures or degenerative diseases is as a routine surgical procedure. Less duration of the healing period and the creation of minimal fibrous tissue and its replacement with bone tissue can be effective in return to health. OBJECTIVES: The aim of this study was to evaluate the histopathological changes following administration of platelet-rich plasma at the site of  removed femoral head in rabbits. METHODS: Twenty male New Zealand white rabbits were distributed into two groups including: control (underwent femoral head osteotomy, FHO) and treatment (underwent FHO and planting the platelet-rich plasma on surgical site FHO₊ PRP). In both groups after general anesthesia, femoral head was removed using standard method. In group 2, pre-prepared auto log PRP was used at the site of surgery. After eight weeks all animals were euthanised, femur and its  surrounding healing tissues were cut 2cm  far from the head of femur and removed. Slides were prepared from each sample  through serial sectioning and were stained with H&E and Mason Trichrome. Qualitative changes such as granulation tissues, cartilage and bone formation and their organization and timeliness, thickness of collagen fibers and cellular changes were compared. To quantify the changes, whole surface of the Mason Trichrom stained samples underwent scan with ×50 magnifications and then area of different new formation tissues was measured. Average occupancy levels of each tissue, their ratio to whole surface of sample and to each other in two groups were calculated and compared. RESULTS: In PRP treated group ratio of cartilage tissue to granulation tissue and formation of bone to granulation tissue is significantly more than these parameters in control group. Results indicate faster healing on the damaged area in group 2. Also in group 2, cartilage and bone tissues formation in the healing process was more orderly. CONCLUSIONS: PRP could accelerate healing of bone tissue that is cut at the head of the rabbit’s femur. So it seems that the use of PRP as a treatment protocol in these cases could be suggested.