Synergistic Effects of Platelet-Rich Plasma and Amniotic Membrane on Tendon Healing in a Rabbit Model

Tendon repair remains a significant clinical challenge due to the slow rate healing process. While both platelet rich plasma (PRP) and amniotic membrane (AMNIO) therapies have been individually utilized for promoting tendon regeneration, their combined effects are still largely unexplored. Achilles tendon injuries were induced in 48 male New Zealand white rabbits and treated with one of four interventions: control (CTRL), PRP injection, AMNIO wrap, or a combination of PRP and AMINO (PRP+AMNIO). Tendon healing was assessed at 4-, 8-, and 12-weeks post-surgery using macroscopic evaluation and histological analysis, including hematoxylin and eosin (H&E) and Masson’s trichrome staining to evaluate collagen deposition, inflammation, and tissue morphology. All data were statistically analyzed. The PRP+AMNIO group demonstrated superior tendon healing compared to CTRL, PRP, and AMNIO groups. Macroscopic evaluation revealed a significantly improved tendon structure in the PRP+AMNIO group, showing 5.5-, 5-, and 4.7-fold improvements compared to the CTRL group at weeks 4, 8, and 12, respectively (p<0.0001). Compared to the CTRL group, the PRP+AMNIO group showed reduced inflammation and hemorrhage, with reduction of up to 7.5-fold (p<0.0001). Collagen fiber linearity significantly improved in the PRP+AMNIO group by week 12, with a 5.7-fold increase compared to the CTRL group (p=0.0007). Moreover, the PRP+AMNIO group exhibited significantly higher collagen deposition than the PRP and AMNIO groups alone at weeks 8 and 12 (p<0.0001). In conclusion, compared to the control group, the combination of a-PRP injection with AMNIO wrap improves rabbit Achilles tendon recovery by reducing inflammation, promoting collagen deposition, and enhancing tendon morphology.