A comparison between the efficacy of eccentric exercise and extracorporeal shock wave therapy on tendon thickness, vascularity, and elasticity in Achilles tendinopathy: A randomized controlled trial

OBJECTIVES: This study aims to compare the efficacy of the eccentric exercise (EE) and extracorporeal shock wave therapy (ESWT) on chronic midportion Achilles tendinopathy and evaluate the efficacy of these treatment modalities on tendon thickness, vascularity, and elasticity. PATIENTS AND METHODS: In this randomized controlled trial, a total of 63 patients (40 females, 23 males; mean age: 37.3±12.2; range, 18 to 55 years) with chronic midportion Achilles tendinopathy were enrolled between April 2017 and December 2019. The patients were allocated randomly to two groups: the first group was treated with EE every day for three months with the Alfredson protocol, and the second group received four sessions of ESWT at weekly intervals. The study was terminated at the end of three months. Visual Analog Scales (VAS), Victorian Institute of Sports Assessment-Achilles (VISA-A) questionnaires, and ultrasonography measurements were assessed before and after treatment. Patient pain was evaluated at the two-year follow-up. RESULTS: At the three-month follow up, VAS scores decreased, and VISA-A scores increased in both groups (p<0.001). At the two-year-follow-up, VAS scores significantly decreased in the EE group (p<0.001), but the difference was statistically insignificant in the ESWT group (p=0.095). Tendon thickness and stiffness increased in the EE group (p=0.003 and p=0.03, respectively) while the difference was statistically insignificant in the ESWT group after treatment (p=0.173 and p=0.702, respectively). CONCLUSION: Eccentric exercise and ESWT are efficient in the short term, whereas EE is efficient on tendon pain in the long term. While EE increases tendon thickness and stiffness, ESWT has no effect on these measures.