Investigation the Effect of Human Recombinant Epidermal Growth Factor on Rotator Cuff Healing: An Experimental Model

Objective To investigate the effectiveness of human recombinant epidermal growth factor in the healing of rotator cuff tear in the rabbit shoulder. Methods Rotator cuff tears (RCTs) were experimentally created on both shoulders of 20 New Zealand rabbits. The rabbits were divided into the following groups: RCT (sham group; n = 5), RCT + EGF (EGF group; n = 5), RCT + transosseous repair (repair group; n = 5), and RCT + EGF + transosseous repair (combined repair + EGF group; n = 5). All rabbits were then observed for 3 weeks, and biopsies were taken from the right shoulders in the third week. After three more weeks of observation, all rabbits were sacrificed, and a biopsy removed from their left shoulders. All biopsy material was stained with haematoxylin & eosin (H&E) and vascularity, cellularity, the proportion of fibers and the number of fibrocartilage cells were evaluated under light microscope. Results The highest collagen amount and the most regular collagen sequence was detected in the combined repair + EGF group. The repair group and the EGF group showed higher fibroblastic activity and capillary formation when compared with the sham group, but the highest fibroblastic activity and capillary formation with highest vascularity was detected in the combined repair + EGF group ( p < 0.001). EGF seems to improve wound healing in the repair of RCT. The EGF application alone, even without repair surgery, seems to be beneficial to RCT healing. Conclusion In addition to rotator cuff tear repair, application of human recombinant epidermal growth factor has an effect on rotator cuff healing in rabbit shoulders.