Hyaluronic Acid Injection After Failed Arthroscopic Microfracture in Osteochondral Lesion of the Talus

Category: Ankle Introduction/Purpose: The optimal treatment for symptomatic osteochondral lesion of the talus (OLT) after failed arthroscopic microfracture has been a controversial issue. The use of viscosupplementation for treatment of OLT has been gradually increasing. The hyaluronic acid (HA) injection is believed to play an important role in reducing pain and inflammation, and promoting tissue repair. The purpose of this study is to evaluate the clinical outcomes of intra-articular HA injection for the patients with failed arthroscopic microfracture in OLT. Methods: This study included 12 patients who received three weekly injections of intra-articular HA after arthroscopic microfracture for OLT between October 2014 and October 2015. Five men and seven women were included in this study. The average age at the time of injection was 41 years (range, 19-63 years). All patients had recurrent pain for at least 6 months after the index surgery. The patients were followed for 6.1 months (range: 5.0-7.0). At each visit, the efficacy of HA injection was evaluated by a Visual Analog Scale (VAS), American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot score and Foot and Ankle Outcome Score (FAOS) pain subscale. In addition, subjective satisfactions were assessed by the Alexander scale. Results: The mean period from the arthroscopic microfracture to the intra-articular HA injection was 26.5 months (range: 6.0- 87.0). Mean VAS decreased from 6.7 ± 1.1 at pre-injection to 2.4 ± 1.6 at post-injection six weeks (p < 0.001), 3.1 ± 1.5 at three months (p = 0.002) and 3.8 ± 2.3 at six months (p = 0.02). Mean AOFAS score improved from 61.0 ± 9.1 at pre-injection to 85.3 ± 11.3 at post-injection six weeks (p < 0.001), 82.9 ± 10.4 at three months (p < 0.001) and 80.4 ± 13.8 at six months (p = 0.001). Mean FAOS pain subscale also improved from 53.2 ± 4.2 at pre-injection to 71.1 ± 9.4 at post-injection six weeks (p < 0.001), 66.7 ± 7.2 at three months (p = 0.001) and 64.4 ± 9.5 at six months (p = 0.036). According to the Alexander scale, there were 58.3% (7/12) good, 25.0% (3/12) fair, and 16.7% (2/12) poor results at post-injection six months. There was no adverse effect. Conclusion: In this study, we found that the main improvement in clinical outcomes occurred during the first six weeks and significantly maintained until at least three or six months. We believe that the HA injection could be a useful treatment option after failed arthroscopic microfracture in OLT