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

Abstract

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.

Injectable bioactive glass/sodium alginate hydrogel with immunomodulatory and angiogenic properties for enhanced tendon healing

“… 57 Besides, a previous study reported that BG can improve the integration between tendon and bone in rotator cuff tendon repair. 58 Therefore, we speculated that BG may contribute to tendon tissue healing, and our results demonstrated that delivering BG via an injectable hydrogel could be a promising therapeutic option.…”

The effects of orthobiologics in the treatment of tendon pathologies: a systematic review of preclinical evidence

“…Studies using rotator cuff repair models reported controversial results, ranging from no improvements [33] or detrimental effects on cell density and vascularization [22], to the amelioration of histological appearance [31, 64] and fibers organization [31]. Studies involving injury at the enthesis consistently reported improvements in terms of reduced inflammation and vascularity, [49] deposition of type I and type II collagen [126], fibers organization [115] and histologic appearance [127] following blood‐derived products application. Only one study reported a detrimental effect of platelet‐rich fibrin matrix on tissue healing with formation of fibrotic tissue [50].…”

“…The expression of the growth factors TGFβ and IGF, as well as the tendon specific marker TNMD, is increased in the first phases of tendon healing in treated animals, whilst they all decreased at later time‐points [47, 60, 73–75]. In a model of rotator cuff tear, an increase in BMP‐2 after treatment, possibly benefitting the healing of the bone‐tendon interface was reported [115].…”

“…Two studies conducted in collagenase induced tendinopathy models were investigated, one reporting improvements after treatment [45] and the other showing no effect of PRP [100]. Reports about rotator cuff repair models consistently showed improved biomechanical properties [22] in terms of maximum failure load [31, 33, 50, 81, 115], resistance to mechanical stress [50], tensile strength [49] and stiffness [31, 33, 50]. Notably the use of frozen platelet concentrates would not allow to obtain the same results as fresh products [61, 127].…”