Early Outcome of a Single Peri-Tendinous Hyaluronic Acid Injection for Mid-Portion Non-Insertional Achilles Tendinopathy - A Pilot Study

Abstract

AimThe aim of this study was to evaluate the efficacy and safety of a single, peri-tendinous injection of hyaluronic acid for mid-portion, non-insertional Achilles tendinopathy. Materials And MethodsA prospective, open labelled, single center, pilot study was conducted. All patients enrolled received a single peri-tendinous injection of Ostenil Tendon™ (40 mg/2 ml 2% HA with 0.5% mannitol). Outcome measures were Visual Analogue Scale (VAS) pain score and Manchester-Oxford Foot Questionnaire (MOxFQ) scores at 2 weeks and at final follow at 12 weeks. Any major and minor adverse effects were recorded. To assess change in VAS and MOxFQ scores, t test and Wilcoxon signed rank test were employed. ResultsSeventeen patients were enrolled in this study with a mean follow-up of 12 weeks. Mean pre-injection VAS score was 9.38 cm (9-9.8), which significantly reduced post-injection to a mean score of 4.09 cm (2-8) at week-2 stage, and further improved to 3.01 cm (2-3.9) at the final follow-up (p < 0.0001). MOxFQ score showed a significant improvement from pre-injection value of 67.77 (63.03-72.55) to 31.18 (13-60) at week-2 stage, and further improved to 24.20 (15.73-32.67) at the final follow-up (p < 0.0001). The mean improvement from pre-injection to the final follow up was 43.57 (34.25-52.90). No adverse effects for injections were recorded. ConclusionThis small series suggests an encouraging response of a single injection of HA as an effective and safe option for non-insertional Achilles tendinopathy.