A prospective observational study on the beneficial effects and tolerability of a cetylated fatty acids (CFA) complex in a patch formulation for shoulder tendon disorders

BACKGROUND: The advancement of physiopathological knowledge of tendon structures has shown that, in conditions of overload, there is the onset of both degenerative phenomena, such as the production of metalloproteases, apoptosis of tendon cells and neoangiogenesis, and regenerative and protective phenomena, such as the production of IGF-1 and nitric oxide. Tendinopathy results from the imbalance between these two groups of factors, leading to degeneration, weakening, and fissuring of the tendons, with the presence of local pain. The aim of the study was to evaluate the efficacy and tolerability of cetylated fatty acids (CFA) patch formulation in the control of acute localized shoulder pain and recovery of function in patients with tendinopathies. METHODS: A prospective, single-center, no-profit observational study conducted in accordance with Good Clinical Practice. Thirty patients with recent onset shoulder pain symptoms (1–3 months) related to bursitis and tenosynovitis, with a diagnosis of shoulder tendon pathology confirmed by ultrasound examination, was evaluated for shoulder pain and function using the Constant Murley Score. Patients used 1 patch containing CFA for 8 h per day for 10 days. At 10 (V1) and 35 (V2) days after the first visit (V0), the Constant Score, treatment compliance and product tolerability were evaluated. RESULTS: Thirty patients completed the treatment. At V0 the mean Constant Score (CS) was 32.37 ± 11.86, during V1 the mean CS was 50.68 ± 14.30, and at V3 the mean CS was 51.07 ± 15.29. The CS increased significantly between V0 and V1 (p < 0.0001) but did not vary significantly between V1 and V2 (p = 1). The tolerability of the product was excellent. CONCLUSIONS: Application of the CFA-based patch for 10 consecutive days in patients with shoulder tendinopathies was effective in reducing local pain and resulted in a good recovery of function. The results achieved at day 10 were maintained for 25 days, until the follow-up visit at day 35. CFA-based patch, thanks to their efficacy and tolerability, seems to be a promising solution to improve pain and functionality in subject with shoulder tendinopathy. TRIAL REGISTRATION: The study was approved by the Ethics Committee of Azienda USL Toscana Nord Ovest (protocol code 2018RIAB105) and conducted in accordance with Good Clinical Practice and the ethical principles outlined in the Declaration of Helsinki.