Editing Navicular bone (section)

== Human anatomy ==
The navicular bone in humans is one of the [[tarsus (skeleton)|tarsal bones]], found in the [[foot]]. Its name derives from the human bone's resemblance to a small boat, caused by the strongly concave [[Anatomical terms of location#Proximal and distal|proximal]] [[joint|articular surface]]. The term ''navicular bone'' or ''hand navicular bone'' was formerly used for the [[scaphoid bone]],<ref>{{cite web
| url   = http://www.bartleby.com/107/54.html
| title = Gray's Anatomy, 6b. The Hand. 1. The Carpus. 4
| year  = 1918 | access-date = 2018-05-11
}}</ref> one of the [[Carpal bones|carpal bone]]s of the [[wrist]].

The navicular bone in humans is located on the [[Anatomical terms of location#Relative directions|medial]] side of the [[foot]], and articulates proximally with the [[Talus bone|talus]], [[Anatomical terms of location#Relative directions|distally]] with the three [[cuneiform bone]]s, and [[Anatomical terms of location#Relative directions|laterally]] with the [[Cuboid bone|cuboid]].

It is the last of the foot bones to start [[ossification]] and does not tend to do so until the end of the third year in girls and the beginning of the fourth year in boys, although a large range of variation has been reported.<ref>{{cite book
| url   = https://books.google.com/books?id=cYYrHeugqV4C&q=juvenile+skeleton
| title = The Juvenile Skeleton |author1=Louise Scheuer  |author2=Sue Black
 |name-list-style=amp | year  = 2004 
| isbn = 9780080474595 }}</ref>

{{multiple image | direction = horizontal |align=left
 | caption_align = center
 | image1=Slide21DEN.JPG
 | alt1= 
 | caption1=Navicular bone. Superior view.
 | image2=Slide23DEN.JPG
 | alt2=
 | caption2=Navicular bone. Inferior view.
}}
{{Clear}}
[[File:NavicularFracMark.png|thumb|upright|Fracture of the navicular bone]]

The [[Tibialis posterior muscle|tibialis posterior]] is the only muscle that attaches to the navicular bone. The main portion of the muscle inserts into the tuberosity of the navicular bone.<ref name=Bojsen>{{cite book |last1=Bojsen-Møller |first1=Finn  |last2=Simonsen |first2=Erik B. |last3=Tranum-Jensen |first3=Jørgen| year=2001 |title=Bevægeapparatets anatomi |edition=12th |language=da |trans-title=Anatomy of the Locomotive Apparatus | isbn =978-87-628-0307-7|page=293 }}</ref> An [[accessory navicular bone]] may be present in 2–14% of the general population.<ref>{{Cite web|url=https://mdmercy.com/centers-of-excellence/orthopedics-bone-and-joint/institute-for-foot-and-ankle-reconstruction|title=Top Rated Foot Surgeons - Foot & Ankle Institute in Baltimore- Mercy|website=Mercy Medical Center}}</ref><ref>{{Cite web|url=https://www.wheelessonline.com/bones/accessory-navicular/|title=Accessory Navicular|date=2 June 2020}}</ref><ref>{{cite web|url=http://www.macrorad.com/case-reports/symptomatic-accessory-navicular-bone.html|title=Macrorad Teleradiology Case Report - SYMPTOMATIC ACCESSORY NAVICULAR BONE|last=www.mynameiskaan.com}}</ref>

===Clinical significance===
The human navicular is not a commonly broken bone but it breaks due to two reasons. The first mechanism is a stress fracture which happens commonly in athletes,<ref>{{Cite web|url=https://www.nba.com/bucks/news/medical-update-pau-gasol|title=Medical Update On Pau Gasol|website=Milwaukee Bucks|language=en|access-date=2019-12-08}}</ref> and the other mechanism is a high energy trauma.  

The navicular bone is a keystone of the foot: it is part of the coxa pedis and articulates with the talus, first, second and third cuneiform, cuboid and calcaneus. It plays an important role in the biomechanics of the foot, helping in inversion, eversion, and motion; it is a structural link between midfoot and forefoot and it is part of the longitudinal and transverse arch of the foot.