ESWT Combined with Ultrasound-Guided PRP Injection for Treating Achilles Tendinopathy:An Experimental Study

Wang Jincheng; Nie Jiping; Qin Yuxing; Huo Tianqi; Zhang Guolong

Abstract：Objective Objective To investigate the synergistic mechanism and efficacy of extracorporeal shock wave therapy(ESWT)combined with ultrasound-guided injection of autologous platelet rich plasma(PRP)on the repair of Achilles tendinopathy.Methods In this study,rats were prepared by injection of prostaglandin E2 at Achilles tendon insertion point,and were randomly divided into non-intervention group,ESWT intervention group,PRP injection treatment group and combined treatment group.The number of inflammatory cells,collagen arrangement,positive expression rate of type Ⅰ,Ⅲ collagen and apoptotic cells in the treatment of Achilles tendinopathy were compared by HE staining,immunohistochemistry and deoxyribonucleotide-terminal transferase-mediated dUTP nick-end labeling(TUNEL)staining at 4 and 8 weeks after surgery,and the efficacy and mechanism of ESWT combined with PRP in the treatment of Achilles tendinopathy were clarified.Results(1)The HE staining images showed that the Achilles tendon collagen fibers in the non-intervention group were disordered and fractured at 4 weeks after modeling,and the Achilles tendon collagen fibers were continuous after 8 weeks,the cell density increased,the collagen fiber content was small,and the tissue boundaries were blurred,and the Achilles tendon tissue of each treatment intervention(ESWT intervention group,PRP injection treatment group,and combined treatment group)was definitely improved at the 4th and 8th weeks,and the overall performance was that the content of collagen fibers increased,the arrangement was orderly,and the tissue was neat and dense.Compared with the non-intervention group,the inflammatory cell count in each intervention group was significantly reduced at the 4th and 8th weeks(P＜0.05),and the collagen fibers in the combined treatment group were neatly and densely sorted and evenly spaced at the 8th week,and the inflammatory cell count was significantly reduced compared with the ESWT intervention group and the PRP injection treatment group(P＜0.05).(2)The expression results of collagen fibers showed that the positive expression of Collagen Ⅰ and CollagenⅢ.in the non-intervention group was lower at 4 weeks and 8 weeks.Compared with the non-intervention group,the positive expressions of Collagen Ⅰ and Collagen Ⅲ.in the other groups were relatively increased(P＜0.05),and the difference was statistically significant,and the positive expressions of Collagen Ⅰ and Collagen Ⅲ.in the combination treatment group were higher than those in the ESWT intervention group and PRP injection treatment group(P＜0.05).(3)The results of cell apoptosis indicate that the non intervention group had the highest positive rate of apoptotic cells,and it decreased after 8 weeks compared to 4 weeks.The positive rate of apoptotic cells in each intervention group was lower than that in the non intervention group(P＜0.05),and the combination therapy group had the lowest rate.Conclusion ESWT combined with ultrasound-guided PRP injection can promote tendon cell proliferation,promote collagen synthesis,shorten the healing cycle,and promote the repair of Achilles tendinopathy by inhibiting inflammatory response and apoptosis.