Hormones and tendinopathies: the current evidence.

BACKGROUND: Tendinopathies negatively affect the quality of life of millions of people, but we still do not know the factors involved in the development of tendon conditions. SOURCES OF DATA: Published articles in English in PubMed and Google Scholar up to June 2015 about hormonal influence on tendinopathies onset. One hundred and two papers were included following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. AREAS OF AGREEMENT: In vitro and in vivo, tenocytes showed changes in their morphology and in their functional properties according to hormonal imbalances. AREAS OF CONTROVERSY: Genetic pattern, sex, age and comorbidities can influence the hormonal effect on tendons. GROWING POINTS: The increasing prevalence of metabolic disorders prompts to investigate the possible connection between metabolic problems and musculoskeletal diseases. AREAS TIMELY FOR DEVELOPING RESEARCH: The influence of hormones on tendon structure and metabolism needs to be further investigated. If found to be significant, multidisciplinary preventive and therapeutic strategies should then be developed.