Growth factors in the management of sport-induced tendinopathies: results after 24 months from treatment. A pilot study.

AIM: The efficacy of PRP in the treatment of tendinopathies has been already studied both in in vitro and in clinical studies. This paper describes the local and the systemic effects of US-guided autologous PRP (Platelet Rich Plasma) injections in chronic tendinopathies in sportspersons. METHODS: Fifteen patients (13 male, 2 female) between 17 and 68 years old, affected by chronic tendinopathies at different sites were treated with an echographically guided injection of autologous PRP within the pathological area of the tendons. VISA score and MRI data were collected pre interventions and after 90 days and 24 months from treatment. Changes in different inteleukins (ILs), tumour necrosis factor α (TNF α), interferon γ, vascular endothelial growth factor (VEGF), endothelial growth factor (EGF), chemokine (C-C motif) ligand 2 (CCL2), were analysed at four time points in the peripheral blood of five patients. RESULTS: After 90 days the VISA score significantly improved from 36±12 (range 21-64) to 74±17 (range 40-92). Reduction of irregularities was found in 80% of the tendons. After 24 months patients reported an average VISA score of 73±16 (range 42-100). No changes in IL, TNF α and interferon γ were observed. VEGF, EGF and CCL2 decreased progressively from 30m to 3 h after the treatment and returned to near the baselines after 24 h. CONCLUSION: PRP injection allow an improvement of the clinical symptomatology, which is well maintained at least for two years from treatment. The PRP-based local therapy could influence systems homeostasis and antidoping evaluations, but, in our opinion, it doesn't represent a doping substance in itself.