564 - Chronic Achilles Tendinopathy Treated With Leukocyte-Rich PRP: A Case Report

Case Diagnosis: Chronic Achilles tendinopathy

Case Description: A 64-year-old male presented with 6 months of right heel pain and inability to ambulate without a limp, run, or bike. Ultrasound imaging demonstrated a partial tear at the insertion of the Achilles tendon with calcific enthesopathy. He underwent ultrasound-guided leukocyte-rich platelet rich plasma (LR-PRP) injection at that time. Pain, functionality, and tissue healing were assessed with the Visual Analog Scale, ability to tolerate physical activity, and ultrasound imaging, respectively. At 12 weeks post-intervention, the patient demonstrated an 87.5% improvement in pain and could resume stationary biking without resistance limitations. The tear showed progressive healing through week 8 but became slightly enlarged with the resumption of stationary biking.

Discussions: The Achilles tendon has a cumulative lifetime injury incidence of 24% in athletes, specifically at the enthesis. Risk factors include excessive exercise and older age, with a male-to-female ratio of 3.5:1. In insertional Achilles tendinopathy, the degeneration involves loss of parallel collagen I fibers, fatty infiltration, and capillary proliferation. Altered collagen fiber structure in enthesopathies can lead to calcification secondary to inflammation and mineralization. Current conservative treatment results in requirement for surgery in 25-45% of patients, emphasizing the need for improvement. Basic science studies have demonstrated the benefits of PRP in healing tendon injuries with the stimulation of growth factors including PDGF, TGF-β, and VEGF. The idea that LR-PRP induces greater acute inflammation than leukocyte-poor PRP is supported by in vitro and in vivo studies, but whether the response induced by LR-PRP affects the healing process is undetermined.

Conclusions: With the improvements in pain, functionality, and tissue healing with LR-PRP in chronic Achilles tendinopathy highlighted in this case, future studies are recommended to explore the full effects of LR-PRP on chronic tendon injuries.