Effect of Platelet-Rich Plasma and Bioactive Glass Powder for the Improvement of Rotator Cuff Tendon-to-Bone Healing in a Rabbit Model

To test the hypothesis that a platelet-rich plasma (PRP) plus bioactive glass (BG) mixture could shorten the tendon-bone healing process in rotator cuff tendon repair, thirty mature male New Zealand white rabbits were randomly divided into three groups, Control, PRP, and PRP + BG. All groups underwent a surgical procedure to establish a rotator cuff tendon healing model. Mechanical examinations and histological assays were taken to verify the adhesion of the tendon-bone. Real-time PCR was adopted to analyze Bone Morphogenetic Protein-2 (BMP-2). The maximum load-to-failure value in mechanical examinations was significantly higher in the PRP + BG group than that in the control group after six weeks (Control 38.73 ± 8.58, PRP 54.49 ± 8.72, PRP + BG 79.15 ± 7.62, p < 0.001), but it was not significantly different at 12 weeks (PRP 74.27 ± 7.74, PRP + BG 82.57 ± 6.63, p = 0.145). In histological assays, H&E (hematoxylin-eosin) staining showed that the interface between the tendon-bone integration was much sturdier in the PRP + BG group compared to the other two groups at each time point, and more ordered arranged tendon fibers can be seen at 12 weeks. At six weeks, the mRNA expression levels of BMP-2 in the PRP + BG group were higher than those in the other groups (PRP + BG 0.65 ± 0.11, PRP 2.284 ± 0.07, Control 0.12 ± 0.05, p < 0.05). However, there was no significant difference in the mRNA expression levels of BMP-2 among the three groups at 12 weeks (p = 0.922, 0.067, 0.056). BMP-2 levels in PRP and PRP+BG groups were significantly lower at 12 weeks compared to six weeks (p = 0.006, <0.001).We found that the PRP + BG mixture could enhance tendon-bone healing in rotator cuff tendon repair.