Outcomes following extracorporeal shockwave therapy for the treatment of insertional and non-insertional Achilles tendinopathy at 2 year follow-up: a retrospective review

J. Butler, D. Zheng, B. DeClouette, C. Walls, G. Jejelava, M. Azam, J. Kennedy

Introduction: The purpose of this retrospective clinical study was to evaluate outcomes following extracorporeal shockwave therapy (ESWT) for the treatment of Achilles tendinopathy.

Methods: This retrospective cohort study included clinical data from 95 patients who underwent ESWT for insertional (IAT) or non-insertional (NAT) Achilles tendinopathy between 3/3/2017 to 2/8/2022 with a minimum of 1 year follow-up. Data regarding patient demographics, subjective clinical outcomes, radiographic outcomes, treatment characteristics, complications and failures were recorded. Failure was defined as no improvement in VISA-A nor VAS scores and/ or surgical intervention. Subgroup analysis was conducted to identify predictors of poor outcomes. Paired student’s t-tests and Welch’s t-tests were calculated. Regression analysis was carried out to identify predictors of poor outcomes.

Results: In total, 95 patients (109 ankles) with a mean age of 54.1 ± 14.0 years underwent ESWT for Achilles tendinopathy at a mean follow-up of 25.7 ± 15.0 months. Thirty-nine patients were in the NAT cohort and 56 patients were in the IAT cohort. Both NAT and IAT cohorts had a similar improvement in VISA-A score (p=0.365), VAS scores (p=0.65) and demonstrated a similar return to play time (p=0.34). There was a higher failure rate in the IAT cohort (51.8%) than the NAT cohort (23.1%). Patients who received platelet-rich plasma (PRP) had a higher failure rate (71.4%) than those who did not receive PRP (19.6%). Regression models found that treatment with PRP, MRI severity and female sex were associated with worse outcomes.

Conclusion: This retrospective study demonstrated a high failure rate at short-term follow-up in patients who underwent ESWT for insertional Achilles tendinopathy. Predictors of poor outcomes included treatment with PRP, MRI severity and female sex. Further studies with larger patient cohorts and longer follow-up are necessary to determine the role of ESWT in the treatment of Achilles tendinopathy.