Influence of Radial Pressure Wave Therapy (RPWT) on collagenase-induced Achilles tendinopathy treated with Platelet Rich Plasma and Autologous Adipose Derived Stem Cells

Tendinopathy treatment poses a current challenge for sport medicine due to unique physiology and biomechanics of tendons.The goal of this work was to compare the efficacy of the addition of the radial pressure wave therapy (RPWT) treatment to injection of autologous Adipose Derived Stem Cells (ADSCs) or Platelet Rich Plasma (PRP) in the therapeutic procedure for collagenase induced Achilles tendinopathy in sheep.14 sheep (aged 5 and 6 years, Polish Mountain Sheep breed, weight 60-70 kg) were injected bacterial collagenase type 1A-S (Clostridium histolyticum, C-5894, Sigma Aldrich, Poznań, Poland) bilaterally to Achilles tendons.Subsequently, the animals were injected with PRP (7 sheep) or ADSCs (7 sheep) to previously induced tendinopathy foci.Left limbs of all the animals were additionally treated with RPWT focused above the tendinopathy origins.Treatment progress was controlled by ultrasound scans, and tendon samples were taken on the 126th day of the experiment.Tendon samples taken from the sheep treated with RPWT+ADSCs showed lower cellularity and the highest number of thick collage fibers.Samples taken from the sheep treated with RPWT+PRP showed an elevated rate of neovascularization.Addition of the RPWT to ADSCs injections in the treatment of induced Achilles tendinopathy in sheep resulted in good quality of the tissue regeneration.Dual therapy with RPWT+PRP injection can lead to neovascularization in the tendon tissue.