Efficacy of heavy eccentric calf training for treating mid-portion Achilles tendinopathy: a systematic review and meta-analysis

Objective To assess the effectiveness of heavy eccentric calf training (HECT) in comparison with natural history, traditional physiotherapy, sham interventions or other exercise interventions for improvements in pain and function in mid-portion Achilles tendinopathy. Design A systematic review and meta-analysis were conducted as per the PRISMA guidelines. Data sources PUBMED, CINAHL (Ovid) and CINAHL (EBSCO) were searched from inception until 24 September 2018. Eligibility criteria Randomised controlled trials comparing HECT to natural history, sham exercise, traditional physiotherapy and other exercise interventions were included. Primary outcome assessing pain and function was the Victorian Institute of Sports Assessment-Achilles. Results Seven studies met the inclusion criteria. This review suggests HECT may be superior to both natural history, mean difference (MD) (95% CI) of 20.6 (11.7 to 29.5, one study) and traditional physiotherapy, MD (95% CI) of 17.70 (3.75 to 31.66, two studies). Following removal of one study, at high risk of bias, due to pre-planned sensitivity analysis, this review suggests HECT may be inferior to other exercise interventions, MD (95% CI) of -5.65 (-10.51 to -0.79, three studies). However, this difference is unlikely to be clinically significant. Conclusion Current evidence suggests that HECT may be superior to natural history and traditional physiotherapy while HECT may be inferior to other exercise interventions. However, due to methodological limitations, small sample size and a lack of data we are unable to be confident in the results of the estimate of the effect, as the true effect is likely to be substantially different.