Editing Trigger finger (section)

{{short description|Locking of a finger when at full flexion}}
{{about|the disorder|other uses|Triggerfinger (disambiguation)}}
{{Distinguish|De Quervain syndrome}}
{{Infobox medical condition (new)
| name          = Trigger finger
| synonyms      = Trigger digit, trigger thumb,<ref name=OI2018/> stenosing tenosynovitis<ref name=OI2018/>
| image         = TriggerFinger.webm
| caption       = An example of trigger finger affecting the ring finger
| pronounce     = 
| field         = [[Hand surgery]], [[orthopedic surgery]], and [[plastic surgery]]
| symptoms      = Catching or locking of the involved finger, pain<ref name=Mak2008/><ref name=Hub2018/>
| complications = 
| onset         = 50s to 60s years old<ref name=Mak2008/>
| duration      = 
| types         = 
| causes        = 
| risks         = Generally idiopathic, meaning no known cause. Perhaps [[diabetes]]<ref name=Hub2018/>
| diagnosis     = Symptoms and signs<ref name=Mak2008/>
| differential  = Sagittal band rupture
| prevention    = 
| treatment     = [[corticosteroid|Steroid]] injections, surgery. The role of splint immobilization is uncertain<ref name=Hub2018/>
| medication    = 
| prognosis     = 
| frequency     = Relatively common<ref name=Mak2008/>
| deaths        = 
}}

<!-- Definition and symptoms -->
'''Trigger finger''', also known as '''stenosing tenosynovitis''', is  a disorder characterized by catching or locking of the involved [[finger]] in full or near full [[flexion]], typically with force.<ref name=Mak2008>{{cite journal | vauthors = Makkouk AH, Oetgen ME, Swigart CR, Dodds SD | title = Trigger finger: etiology, evaluation, and treatment | journal = Current Reviews in Musculoskeletal Medicine | volume = 1 | issue = 2 | pages = 92–96 | date = June 2008 | pmid = 19468879 | pmc = 2684207 | doi = 10.1007/s12178-007-9012-1 }}</ref> There may be tenderness in the [[palm of the hand]] near the last skin crease (distal [[palmar crease]]).<ref name="Hub2018">{{cite journal | vauthors = Hubbard MJ, Hildebrand BA, Battafarano MM, Battafarano DF | title = Common Soft Tissue Musculoskeletal Pain Disorders | journal = Primary Care | volume = 45 | issue = 2 | pages = 289–303 | date = June 2018 | pmid = 29759125 | doi = 10.1016/j.pop.2018.02.006 | s2cid = 46886582 }}</ref> The name "trigger finger" may refer to the motion of "catching" like a trigger on a gun.<ref name=Mak2008/> The [[ring finger]] and [[thumb]] are most commonly affected.<ref name=OI2018>{{cite web |title=Trigger Finger - Trigger Thumb |url=https://orthoinfo.aaos.org/en/diseases--conditions/trigger-finger/ |website=OrthoInfo - AAOS |access-date=25 June 2018 |date=March 2018}}</ref>

<!-- Cause and diagnosis -->
The problem is generally [[idiopathic]] (no known cause). People with [[diabetes]] might be relatively prone to trigger finger.<ref name="Hub2018" /> The pathophysiology is enlargement of the flexor [[tendon]] and the [[A1 pulley]] of the [[tendon sheath]].<ref name=Hub2018/><ref name=Mak2008/> While often referred to as a type of stenosing tenosynovitis (which implies [[inflammation]]) the pathology is [[mucoid]] degeneration.<ref name=Hub2018/> Mucoid degeneration is when fibrous tissue, such as tendon, has less organized [[collagen]], more abundant [[extracellular matrix]], and changes in the cells ([[fibrocyte]]s) to act and look more like [[cartilage]] cells (chondroid metaplasia). Diagnosis is typically based on symptoms and signs after excluding other possible causes.<ref name=Mak2008/>

<!-- Treatment and epidemiology -->
Trigger digits can resolve without treatment. Treatment options that are [[Disease-modifying treatment|disease modifying]] include [[corticosteroid|steroid]] injections and surgery.<ref name=Hub2018/> [[Splint (medicine)|Splinting]] immobilization of the finger may or may not be disease modifying.