Synergic regenerative effects of polydeoxyribonucleotide and microcurrent on full-thickness rotator cuff healing in a rabbit model

Abstract Background Rotator cuff tendon tears (RCTTs) are common adult injuries. We hypothesized that a local injection of polydeoxyribonucleotide (PDRN) and microcurrent therapy (MIC) would be more effective in regenerating a tendon tear than PDRN administration alone. Objectives To evaluate the effect of PDRN combined with MIC on the regeneration of RCTTs in a rabbit subscapularis tendon chronic RCTT model. Methods Rabbits (n = 24) were allocated to 3 groups at 6 weeks after full-thickness RCTT (FTRCTT): 0.2 mL normal saline (G1-SAL); 0.2 mL PDRN with Sham MIC (G2-PDRN + Sham MIC); and 0.2 mL PDRN with MIC (G3-PDRN + MIC). All treatments were performed under ultrasound guidance. PDRN was injected weekly for 4 weeks and sham MIC or MIC was applied daily for 4 weeks after the first PDRN injection. Results In the G3-PDRN + MIC group, the mean (SD) subscapularis tendon tear size was continuously reduced from 1 week post-treatment to 4 weeks and was significantly decreased as compared with the other 2 groups [6.0 (1.5) vs. G1: 11.5 (1.8) and G2: 9.1 (1.6) mm2; G3 vs. G1, P  Conclusions On gross morphologic, histological, and motion analysis, combined PDRN with MIC therapy was more effective than PDRN alone treating a rabbit model of chronic traumatic FTRCTT.