Editing Tendon (section)

===Injury===
{{anchor|tendon injury}}
Tendons are subject to many types of injuries. There are various forms of [[tendinopathy|tendinopathies]] or tendon injuries due to overuse. These types of injuries generally result in inflammation and degeneration or weakening of the tendons, which may eventually lead to [[tendon rupture]].<ref name = "Sharma P. M">{{cite journal | vauthors = Sharma P, Maffulli N | title = Biology of tendon injury: healing, modeling and remodeling | journal = Journal of Musculoskeletal & Neuronal Interactions | volume = 6 | issue = 2 | pages = 181–190 | year = 2006 | pmid = 16849830 | url = https://www.ismni.org/jmni/pdf/24/14MAFFULLI.pdf | url-status = live | archive-url = https://web.archive.org/web/20240105034830/https://www.ismni.org/jmni/pdf/24/14MAFFULLI.pdf | archive-date = Jan 5, 2024 }}</ref> Tendinopathies can be caused by a number of factors relating to the tendon extracellular matrix (ECM), and their classification has been difficult because their symptoms and histopathology often are similar.

Types of tendinopathy include:<ref name="Maffulli 2003">{{cite journal | vauthors = Maffulli N, Wong J, Almekinders LC | title = Types and epidemiology of tendinopathy | journal = Clinics in Sports Medicine | volume = 22 | issue = 4 | pages = 675–692 | date = October 2003 | pmid = 14560540 | doi = 10.1016/s0278-5919(03)00004-8 }}</ref>
* [[Tendinosis]]: non-inflammatory injury to the tendon at the cellular level. The degradation is caused by damage to collagen, cells, and the vascular components of the tendon, and is known to lead to rupture.<ref>{{cite journal | vauthors = Aström M, Rausing A | title = Chronic Achilles tendinopathy. A survey of surgical and histopathologic findings | journal = Clinical Orthopaedics and Related Research | volume = 316 | issue = 316 | pages = 151–164 | date = July 1995 | pmid = 7634699 | doi = 10.1097/00003086-199507000-00021 | s2cid = 25486134 }}</ref> Observations of tendons that have undergone spontaneous rupture have shown the presence of collagen fibrils that are not in the correct parallel orientation or are not uniform in length or diameter, along with rounded tenocytes, other cell abnormalities, and the ingrowth of blood vessels.<ref name="Sharma P. M"/> Other forms of tendinosis that have not led to rupture have also shown the degeneration, disorientation, and thinning of the collagen fibrils, along with an increase in the amount of glycosaminoglycans between the fibrils.<ref name="Sharma, P. 2005">{{cite journal | vauthors = Sharma P, Maffulli N | title = Tendon injury and tendinopathy: healing and repair | journal = The Journal of Bone and Joint Surgery. American Volume | volume = 87 | issue = 1 | pages = 187–202 | date = January 2005 | pmid = 15634833 | doi = 10.2106/JBJS.D.01850 | s2cid = 1111422 }}</ref>
* [[Tendinitis]]: degeneration with inflammation of the tendon as well as vascular disruption.<ref name="Jozsa, L. 1997"/>
* [[Paratenonitis]]: inflammation of the paratenon, or paratendinous sheet located between the tendon and its sheath.<ref name="Maffulli 2003"/>

Tendinopathies may be caused by several intrinsic factors including age, body weight, and nutrition. The extrinsic factors are often related to sports and include excessive forces or loading, poor training techniques, and environmental conditions.<ref name="Riley, G. 2004">{{cite journal | vauthors = Riley G | title = The pathogenesis of tendinopathy. A molecular perspective | journal = Rheumatology | volume = 43 | issue = 2 | pages = 131–142 | date = February 2004 | pmid = 12867575 | doi = 10.1093/rheumatology/keg448 | doi-access = free }}</ref>