Guerra Flaviá Da Ré*
Department of Anatomy, Federal University of Alfenas, Brazil
*Corresponding author:Guerra Flavia Da Re, Federal University of Alfenas-UNIFAL-MG, Department of Anatomy, Brazil
Submission: October 13, 2017; Published: January 24, 2018
ISSN: 2577-1922 Volume1 Issue3
Tendon lesions are very common and may affect people in their daily activities, work or sports practice. Given the high rate at which such injuries happen, its treatment represents an important share of the health system and of the sport industry . Injuries involving musculoskeletal system are the major causes of suspension of athletes from their activities. Also, tendon and ligaments damage are the leading reason why people seek medical care, regarding musculoskeletal disorders [2,3]. Tendon lesions may be classified as chronic, e.g. tendinitis, or acute, were total or partial tendon rupture occurs. Such rupture may be preceded by chronic inflammation or happen without any previous lesion . According to Szaro et al. , tendon lesions are usually related to factors like chronic disease (including diabetes and rheumatoid arthritis), age and gender.
Studies have shown that tendon injuries are especially common among men between 30 to 49 years old and women after menopause [5,6]. Despite these data the great majority of researches are performed using only male animals, usually rats and mice. Performing a quick search, it is hard to find studies involving tendon rupture or injuries in female animals, and the few ones found are frequently restricted to case studies. In fact, even though there is a consensus that estrogen is an important factor in different musculoskeletal components physiology [7,8], its role in the biology and pathological processes involving tendons has been receiving minor attention by the researchers. Just to put it into context, according to Leblanc  a search in scientific literature using the terms "tendon" and "estrogen" provided 84 results. On the other hand, "bone" and "estrogen" returned 16,717 matches.
It is known that 95% of the tendon dry mass in composed by collagen, 60% of these are type I collagen . The structural arrangements of the collagen fibrils and their association to other extracellular matrix components, such as proteoglycans and metalloproteinases, are responsible for the tendon biomechanical properties . With ageing, there is a decrease in the proteoglycans and water content along with reduction in collagen turnover and in the synthesis of collagenolytic enzymes, predisposing the tissue to lesions . Studies performed with ovariectomized females concluded that estrogen absence leaded to changes in collagen structure in the bone matrix, diminishing the tissue quality .
Markiewics  observed that estrogen receptors in skin have different roles regarding collagen and metalloproteinases biosynthesis. Other studies associated estrogen reduction with a decrease in the concentration of collagen in the pelvis tendon and ligaments, contributing to pelvic organs prolapse [14,15]. All these studies suggest a link between estrogen and collagen explaining, at least in part, women predisposition to tendons injuries. Literature also points to modifications in other components of the extracellular matrix, such as metalloproteinases and proteoglycans. We believe that this poor explored matter is very promising to understand more about the collagen and musculoskeletal system dynamics and particularly to increase our general knowledge on women's health, including some enlightening on the relation of menstrual cycle, menopause and hormone reposition therapy over the tendons, either healthy or after rupture.
© 2018 Guerra Flaviá Da Ré. This is an open access article distributed under the terms of the Creative Commons Attribution License , which permits unrestricted use, distribution, and build upon your work non-commercially.