Editing Pudendal nerve (section)

===Damage===
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The pudendal nerve can be compressed or stretched, resulting in temporary or permanent [[neuropathy]]. Injury to the pudendal nerve manifests more as sensory problems (pain or alteration/loss of sensation) rather than loss of muscle control.<ref name="Kaur2022" /> Irreversible nerve injury may occur when nerves are stretched by 12% or more of their normal length.<ref name=ASCRStextbook />{{rp|655}} If the pelvic floor is over-stretched, acutely (e.g. prolonged or difficult childbirth) or chronically (e.g. chronic straining during [[defecation]] caused by [[constipation]]), the pudendal nerve is vulnerable to stretch-induced neuropathy.<ref name=ASCRStextbook />{{rp|655}} After repeated traction of the pudendal nerve, it starts to be replaced by [[fibrous tissue]] with subsequent loss of function.<ref name="Steele2021" /> [[Pudendal nerve entrapment]], also known as ''Alcock canal syndrome'', is [[neuropathic pain]] in the distribution of the pudendal nerve. It is caused by entrapment of the nerve. The condition is estimated to have a prevalence of 1 in 100000,<ref>{{cite book |last1=Chowdhury |first1=SK |last2=Trescot |first2=AM |editor1-last=Trescot |editor1-first=AM |title=Peripheral Nerve Entrapments: Clinical Diagnosis and Management |date=2016 |publisher=Springer International Publishing |isbn=978-3-319-27482-9 |pages=499–514 |url=https://doi.org/10.1007/978-3-319-27482-9_47 |language=en |chapter=Pudendal Nerve Entrapment}}</ref> and is sometimes associated with professional [[cycle sport|cycling]].<ref>{{cite journal |author=Mellion MB |title=Common cycling injuries. Management and prevention |journal=Sports Med |volume=11 |issue=1 |pages=52–70 |date=January 1991 |pmid=2011683 |doi= 10.2165/00007256-199111010-00004|s2cid=20149549 }}</ref> Systemic diseases such as [[diabetes]] and [[multiple sclerosis]] can damage the pudendal nerve via [[demyelinating disease|demyelination]] or other mechanisms.<ref name=ASCRStextbook />{{rp|37}}  A pelvic tumor (most notably a large [[sacrococcygeal teratoma]]), or surgery to remove the tumor, can also cause permanent damage.<ref>{{cite journal|last1=Lim|first1=Jit F.|last2=Tjandra|first2=Joe J.|last3=Hiscock|first3=Richard|last4=Chao|first4=Michael W. T.|last5=Gibbs|first5=Peter|title=Preoperative Chemoradiation for Rectal Cancer Causes Prolonged Pudendal Nerve Terminal Motor Latency|journal=Diseases of the Colon & Rectum|volume=49|issue=1|pages=12–19|doi=10.1007/s10350-005-0221-7|pmid=16292664|year=2006|s2cid=30584236}}</ref>

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Unilateral pudendal nerve neuropathy inconsistently causes [[fecal incontinence]] in some, but not others. This is because crossover innervation of the external anal sphincter occurs in some individuals.<ref name=ASCRStextbook />{{rp|34}} There is significant overlap of the innervation of the external anal sphincter from the pudendal nerves of both sides.<ref name="Steele2021" /> This allows partial re-innervation from the opposite side after nerve injury.<ref name="Steele2021" >{{cite book | vauthors = Steele SR, Hull TL, Hyman N, Maykel JA, Read TE, Whitlow CB |title=The ASCRS Textbook of Colon and Rectal Surgery |date=20 November 2021 |publisher=Springer Nature |location=Cham, Switzerland |isbn=978-3-030-66049-9 |edition=4th |language=en}}</ref>