[Systematic review about eccentric training in chronic achilles tendinopathy]. / Systematische Literaturanalyse über exzentrisches Training bei chronischer Mid-portion-Achillestendinopathie: Gibt es einen Standard?

BACKGROUND: Throughout the recent decade, eccentric training has become a widely accepted therapy option in the conservative treatment of chronic Achilles tendinopathy. Nevertheless, current recommendations are missing regarding dosage and duration of eccentric training as well as standardized training protocols. OBJECTIVES: Is eccentric training as a conservative treatment in chronic Achilles tendinopathy of beneficial effect versus other conservative treatments? According to the current scientific data, is it possible to recommend dosages and duration of training time of eccentric training? STUDY DESIGN: Systematic review of the current scientific literature on eccentric training as a conservative treatment in chronic Achilles tendinopathy according to the PRISMA-guidelines (Preferred Reporting Items for Systematic Reviews and Meta-Analyses). DATA SOURCE: National library of Medicine (NLM) between the years 1950 and 2010. STUDY ELIGIBILITY CRITERIA: Prospective randomised controlled trials (RCT). PARTICIPANTS: 8 RCTs included 416 subjects with a median number of 42 subjects and a range of 17 to 116 subjects per trial. Median follow-up duration was 12 weeks with a range from 12 to 54 weeks. RESULTS: 124 papers met the eligibility criteria in the NLM, whereas only eight randomised controlled trials were included in this review after screening titles, abstracts and full texts. All included trials demonstrated an improvement in pain after performing equivalent training protocols of eccentric training in chronic Achilles tendinopathy. LIMITATIONS: A pooled statistical evaluation of the included trials could not be performed due to different study designs as well as limited documentation of subjects' compliance. CONCLUSION: In spite of different compliance, effects of eccentric training in conservative treatment of chronic mid-portion-Achilles tendinopathy are promising. Because of the heterogeneous outcome variables (ordinal scale, VAS, FAOS, AOFAS, VISA-A) and the methodological limitations of the trials, no definite recommendation can be published concerning dosage and duration of eccentric training in chronic Achilles tendinopathy.