Editing Hamate bone

{{Short description|Carpal bone in the wrist}}
{{redirect|Hamatum|its use in taxonomy|List of Latin and Greek words commonly used in systematic names#H{{!}}List of Latin and Greek words commonly used in systematic names}}
{{Infobox bone
| Name          = Hamate bone
| Latin         = os hamatum
| Image         = Hamate bone (left hand) 01 palmar view.png
| Caption       = Left hand anterior view (palmar view). Hamate bone shown in red.
| Image2        = Gray228.png
| Caption2      = The left hamate bone
| Origins       =
| Insertions    =
| Pronunciation = {{IPAc-en|'|h|ei|m|@|t}}
| Articulations = Articulates with five bones: <br>the [[lunate bone|lunate]] proximally<br>the [[Fourth metacarpal bone|fourth]] and [[Fifth metacarpal bone|fifth]] [[metacarpals]] distally<br>the [[Triquetral bone|triangular]] medially<br>the [[capitate]] laterally
}}

The '''hamate bone''' (from [[Latin language|Latin]] [[wiktionary:hamatus|hamatus]], "hooked"), or '''unciform bone''' (from [[Latin language|Latin]] ''[[wikt:uncus|uncus]]'', "hook"), Latin '''os hamatum''' and occasionally abbreviated as just '''hamatum''',<ref>{{Cite journal|last1=Gdoura|first1=F.|last2=Trigui|first2=M.|last3=Ellouze|first3=Z.|last4=Hamed|first4=Y. B.|last5=Ayadi|first5=K.|last6=Keskes|first6=H.|date=October 2010|title=Hamatum osteoblastoma|journal=Orthopaedics & Traumatology, Surgery & Research |volume=96|issue=6|pages=712–716|doi=10.1016/j.otsr.2010.02.014|issn=1877-0568|pmid=20692218|doi-access=free}}</ref><ref>{{Cite journal|last1=Mei|first1=Guo-Hua|last2=Wang|first2=Hai-Ming|last3=Fan|first3=Cun-Yi|last4=Zhang|first4=Chang-Qing|last5=Zeng|first5=Bing-Fang|date=October 2014|title=Possibility of the hamatum carpometacarpal joint as a new joint donor site for interphalangeal joint restoration|url=https://pubmed.ncbi.nlm.nih.gov/23982116/|journal=European Journal of Orthopaedic Surgery & Traumatology: Orthopedie Traumatologie|volume=24|issue=7|pages=1175–1180|doi=10.1007/s00590-013-1300-4|issn=1633-8065|pmid=23982116|s2cid=25697262 }}</ref><ref>{{Cite journal|last1=Alp|first1=Nazmi Bülent|last2=Kaleli|first2=Tufan|last3=Kalay|first3=Onur Can|last4=Karpat|first4=Fatih|last5=Akdag|first5=Gokhan|last6=Macunluoglu|first6=Aslı Ceren|last7=Oral|first7=Gamze Saygı|date=2020|title=The Effect of Hamatum Curvature Angle on Carpal Tunnel Volumetry: A Mathematical Simulation Model|journal=Computational and Mathematical Methods in Medicine|volume=2020|pages=7582181|doi=10.1155/2020/7582181|issn=1748-6718|pmc=7312712|pmid=32617118|doi-access=free }}</ref> is a bone in the human [[wrist]] readily distinguishable by its wedge shape and a hook-like process ("hamulus") projecting from its [[Radioulnar|palmar]] surface.

==Structure==
The hamate is an irregularly shaped [[carpal bone]] found within the [[hand]]. The hamate is found within the distal row of carpal bones, and abuts the [[metacarpal]]s of the [[little finger]] and [[ring finger]].<ref name=GRAYS2005>{{cite book|last=Drake|first=Richard L.|title=Gray's anatomy for students|year=2005|publisher=Elsevier/Churchill Livingstone|location=Philadelphia|isbn=978-0-8089-2306-0|author2=Vogl, Wayne |author3=Tibbitts, Adam W.M. Mitchell  |author4=illustrations by Richard |author5= Richardson, Paul }}</ref>{{rp|708–709}}

Adjacent to the hamate on the ulnar side, and slightly proximal and ulnar to it, is the [[pisiform bone]]. Adjacent on the radial side is the [[capitate]], and proximal is the [[lunate bone]].<ref name=GRAYS2005 />{{rp|708–709}}

===Surfaces===
The hamate bone has six surfaces:
* The '''''superior''''', the apex of the wedge, is narrow, convex, smooth, and articulates with the [[lunate bone|lunate]].
* The '''''inferior''''' articulates with the fourth and fifth metacarpal bones, by concave facets which are separated by a ridge.
* The '''''dorsal''''' is triangular and rough for ligamentous attachment.
* The '''''palmar''''' presents, at its lower and ulnar side, a curved, hook-like process, the [[Hamulus of hamate bone|hamulus]], directed forward and laterally.
* The '''''medial''''' articulates with the [[triangular bone]] by an oblong facet, cut obliquely from above, downward and medialward.
* The '''''lateral''''' articulates with the [[capitate]] by its upper and posterior part, the remaining portion being rough, for the attachment of ligaments.

===Hook===
[[File:Hamulus of hamate (left hand) - animation02.gif|thumbnail|Hamate bone of the left hand. Hamulus shown in red.]]
The ''hook of hamate'' ({{langx|la|hamulus}}) is found at the proximal, [[ulnar]] side of the hamate bone. The hook is a curved, hook-like process that projects 1–2&nbsp;mm distally and radially.<ref name=EATHORNE2005>{{cite journal|last=Eathorne|first=SW|title=The wrist: clinical anatomy and physical examination—an update.|journal=Primary Care|date=March 2005|volume=32|issue=1|pages=17–33|pmid=15831311|doi=10.1016/j.pop.2004.11.009}}</ref> The [[ulnar nerve]] hooks around the hook of hamate as it crosses towards the medial side of hand.

The hook forms the ulnar border of the [[carpal tunnel]], and the radial border for [[Guyon's canal]]. Numerous structures attach to it, including ligaments [[pisohamate ligament|from the pisiform]], the transverse carpal ligament, and the tendon of [[flexor carpi ulnaris]].<ref name=EATHORNE2005 />

Its medial surface to the [[flexor digiti minimi brevis (hand)|flexor digiti minimi brevis]] and [[opponens digiti minimi]]; its lateral side is grooved for the passage of the [[flexor tendons]] into the palm of the hand.

===Development===
The ossification of the hamate starts between 1 and 12 months.<ref name=CHLT>{{cite journal|last1=Balachandran|first1=Ajay|last2=Kartha|first2=Moumitha|last3=Krishna|first3=Anooj|last4=Thomas|first4=Jerry|last5=K|first5=Prathilash|last6=TN|first6=Prem|last7=GK|first7=Libu|last8=B|first8=Krishnan|last9=John|first9=Liza|title=A Study of Ossification of Capitate, Hamate, Triquetral & Lunate in Forensic Age Estimation|journal=Indian Journal of Forensic Medicine & Toxicology|date=2014|volume=8|issue=2|pages=218–224|doi=10.5958/0973-9130.2014.00720.8|url=http://www.indianjournals.com/ijor.aspx?target=ijor:ijfmt&volume=8&issue=2&article=052|access-date=18 August 2014|issn=0973-9130|url-access=subscription}}</ref> The hamate does not fully ossify until about the 15th year of life.<ref name=EATHORNE2005 />

===Other animals===
The bone is also found in many other mammals, and is [[homology (biology)|homologous]] with the "fourth distal carpal" of reptiles and amphibians.

==Function==
{{expand section|date=September 2022}}
The carpal bones function as a unit to provide a bony superstructure for the [[hand]].<ref name=GRAYS2005 />{{rp|708}}

==Clinical significance==
The hamate bone is the bone most commonly [[fracture (bone)|fractured]] when a [[golf]]er hits the ground hard with a [[golf club (equipment)|golf club]] on the downswing or a hockey player hits the ice with a slap shot. The fracture is usually a [[hairline fracture]], commonly missed on normal [[radiography|X-rays]]. Symptoms are pain aggravated by gripping, tenderness over the hamate and symptoms of irritation of the [[ulnar nerve]]. This is characterized by numbness and weakness of the fifth digit with partial involvement of the fourth digit as well, the "ulnar 1½ fingers".

The hook of hamate is particularly prone to fracture-related complications such as non-union due to its tenuous blood supply.<ref name=EATHORNE2005 />

It is also a common injury in [[baseball]] players. Several professional baseball players have had the bone removed during the course of their careers.<ref>{{cite news |first=Chris |last=Snow |url=http://www.boston.com/sports/baseball/redsox/articles/2006/06/01/pea_to_have_surgery/ |title=Peña to have surgery |work=The Boston Globe |date=June 1, 2006 |access-date=September 2, 2011}}</ref><ref>{{cite web |first=John |last=Manuel |url=http://www.baseballamerica.com/today/features/040331wrist.html |title=Wrist Troubles Drain Prospects' Power |publisher=Baseball America |date=March 31, 2004 |access-date=September 2, 2011}}</ref><ref>{{cite news |first=Amalie |last=Benjamin |url=http://www.boston.com/sports/baseball/redsox/articles/2007/07/27/hes_gaining_in_arms_race/ |title=He's gaining in arms race |work=The Boston Globe |date=July 27, 2007 |access-date=September 2, 2011}}</ref><ref>{{cite news |agency=Associated Press |url=https://www.espn.com/mlb/news/story?id=5160329 |title=Dickerson has hand, wrist surgery |publisher=ESPN |date=May 3, 2010 |access-date=September 2, 2011}}</ref><ref>{{cite web |first=Kieran |last=Carobine |url=https://philliesnation.com/archives/2011/03/domonic-browns-surgery-a-success/ |title=Domonic Brown's Surgery A Success |publisher=Phillies Nation |date=March 8, 2011 |access-date=September 2, 2011}}</ref><ref>{{cite web |url= https://www.cbssports.com/fantasy/baseball/news/angels-mike-trout-undergoes-hamate-surgery/ |title=Angels' Mike Trout: Undergoes hamate surgery |date=July 5, 2023 |work=CBS Sports |access-date=August 4, 2023}}</ref> This condition has been called "Wilson's Wrist".<ref>WILSON JN. Profiles of the carpal canal. ''J Bone Joint Surg Am''. 1954 Jan;36-A(1):127–132</ref>

The calcification of the hamate bone is seen on X-rays during puberty and is sometimes used in [[orthodontics]] to determine if an adolescent patient is suitable for [[orthognathic intervention]] (i.e. before or at their growth spurt).{{cn|date=January 2023}}

==Etymology==
The etymology derives from the Latin ''hamatus'' "hooked," from ''hamus'' which means "hook".

==Additional images==
<gallery>
 File:Hamate bone (left hand) - animation01.gif|Position of hamate bone (shown in red). Left hand. Animation.
 File:Hamate bone (left hand) - animation04.gif|Hamate bone of the left hand. The hook-like process is called [[Hamulus of hamate bone|hamulus]].
 Image:Hamate bone.jpg|Hamate bone.
 File:RightHumanAnteriorDistalRadiusUlnaCarpals - Hamate bone.png|Right hand anterior view (palmar view). Thumb on top.
 File:RightHumanPosteriorDistalRadiusUlnaCarpals - Hamate bone.png|Right hand posterior view (dorsal view). Thumb on bottom.
 Image:Gray219 - Hamate bone.png|Bones of the left hand. Palmar surface. Hamate shown in yellow.
 Image:Gray220 - Hamate bone.png|Bones of the left hand. Dorsal surface. Hamate shown in yellow.
 Image:Gray422 - Hamate bone.png|Transverse section across the wrist and digits. Hamate shown in yellow.
 File:Ospoignet - Hamate bone.png|Cross section of wrist (thumb on left). Hamate shown in red.
 File:Slide1dsds - Hamate bone.png|Right wrist joint. Deep dissection. Anterior (palmar) view.
</gallery>

== See also ==
{{Commons}}
{{Anatomy-terms}}
* [[Carpal bone]]
* [[Hypothenar hammer syndrome]]

== References ==
{{Gray's}}
{{Reflist}}

{{Bones of upper extremity}}
{{Portal bar|Anatomy}}
{{Authority control}}

{{DEFAULTSORT:Hamate Bone}}
[[Category:Wrist]]
[[Category:Bones of the hand]]
[[Category:Carpal bones]]