Efficacy of Extracorporeal Shock Wave Therapy for Achilles Tendinopathy: A Meta-analysis

BACKGROUND: Achilles tendinopathy is a frequent sports injury, and extracorporeal shock wave therapy (ESWT) has been proposed as a treatment. PURPOSE: To compare outcomes between ESWT and other nonsurgical intervention (including sham shock wave therapy) in Achilles tendinopathy patients. STUDY DESIGN: Systematic review; Level of evidence, 2. METHODS: We included 5 randomized controlled trials and 3 case-control studies published between 2005 and 2018. We analyzed pain scores and other outcomes that were reported in more than 3 of the 8 studies. RESULTS: ESWT was associated with significantly better scores than comparison therapy on the visual analog scale for pain (P < .01), American Orthopaedic Foot & Ankle Society scale (P = .01), Likert scale for satisfaction (P = .03), Roles and Maudsley scale (P < .01), Victorian Institute of Sports Assessment–Achilles questionnaire (P < .01), and numerical rating scale (P = .02). The 2 patient groups did not differ significantly in tenderness (P = .34) or pain threshold (P = .24). Subgroup analysis showed that ESWT led to better VAS pain scores than comparison treatments at both low-energy level (0.06-0.11 mJ/mm(2)) and medium-energy level (0.12-0.25 mJ/mm(2)) and at both shorter (<6 months) and longer (≥6 months) follow-up. CONCLUSION: ESWT improves pain and functional outcomes in patients with Achilles tendinopathy. Further research is needed to determine the optimal energy level.