Left hand anterior view (palmar view). Hamate bone shown in red.
The left hamate bone
|Articulations||Articulates with five bones:
the lunate proximally
the fourth and fifth metacarpals distally
the triangular medially
the capitate laterally
|Anatomical terms of bone|
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 metacarpals of the little finger and ring finger.:708–709
The hamate bone has six surfaces:
- The superior, the apex of the wedge, is narrow, convex, smooth, and articulates with the 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, directed forward and lateralward.
- 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.
The hook forms the ulnar border of the carpal tunnel, and the radial border for Guyon's canal. Numerous ligaments attach to it, including ligaments from the pisiform, the transverse carpal ligament, and the tendon of Flexor carpi ulnaris.
The hamate does not fully ossify until about the 15th year of life.
The bone is also found in many other mammals, and is homologous with the "fourth distal carpal" of reptiles and amphibians.
The hamate bone is the bone most commonly fractured when an amateur golfer hits the ground hard with a golf club on the downswing. The fracture is usually a hairline fracture, commonly missed on normal 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 pinky finger with partial involvement of the ring finger 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.
It is also a common injury in baseball players. Several professional baseball players have had the bone removed during the course of their careers. This condition has been called "Wilson's Wrist".
The calcification of the unciform 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).
- Jose Canseco, Oakland Athletics outfielder (1989)
- Ken Griffey, Jr., Seattle Mariners outfielder (1996)
- Jim Thome, Cleveland Indians first baseman (1996)
- Luis Matos, Baltimore Orioles outfielder (2002)
- Eric Hinske, Atlanta Braves first baseman (2003)
- Ryan Kalish, Boston Red Sox outfielder (2007)
- Dustin Pedroia, Boston Red Sox second baseman (2007)
- Ryan Zimmerman, Washington Nationals third baseman (2007)
- Troy Tulowitzki, Colorado Rockies shortstop (2010)
- Domonic Brown, Philadelphia Phillies outfielder (2011)
- Pablo Sandoval, San Francisco Giants third baseman (2011, right; 2012, left)
- Nick Markakis, Baltimore Orioles outfielder (2012)
- Gordon Beckham, Chicago White Sox second baseman (2013)
- Mike Zunino, Seattle Mariners catcher (2013)
- Wilson Ramos, Washington Nationals catcher (2014)
The etymology derives from the Latin hamatus "hooked," from hamus which means "hook."
Hamate bone of the left hand. The hook-like process is called hamulus.
|Wikimedia Commons has media related to Hamate bone.|
This article uses anatomical terminology; for an overview, see anatomical terminology.
- Drake, Richard L.; Vogl, Wayne; Tibbitts, Adam W.M. Mitchell ; illustrations by Richard; Richardson, Paul (2005). Gray's anatomy for students. Philadelphia: Elsevier/Churchill Livingstone. ISBN 978-0-8089-2306-0.
- Eathorne, SW (Mar 2005). "The wrist: clinical anatomy and physical examination--an update.". Primary care 32 (1): 17–33. PMID 15831311.
- Snow, Chris (June 1, 2006). "Peña to have surgery". The Boston Globe. Retrieved 2011-09-02.
- Manuel, John (March 31, 2004). "Wrist Troubles Drain Prospects' Power". Baseball America. Retrieved 2011-09-02.
- Benjamin, Amalie (July 27, 2007). "He's gaining in arms race". The Boston Globe. Retrieved 2011-09-02.
- "Dickerson has hand, wrist surgery". ESPN. Associated Press. May 3, 2010. Retrieved 2011-09-02.
- Carobine, Kieran (March 8, 2011). "Domonic Brown’s Surgery A Success". Phillies Nation. Retrieved 2011-09-02.
- WILSON JN. Profiles of the carpal canal. J Bone Joint Surg Am. 1954 Jan;36-A(1):127–132
- Christensen, Joe. "Matos has another bad break". Baltimore Sun. Retrieved 3 May 2013.
- "Pedroia played final month, playoffs with cracked hamate bone". ESPN. November 10, 2007. Retrieved 2011-09-02.
- "Zimmerman likely to have surgery after breaking bone in wrist". ESPN. November 6, 2007. Retrieved 2014-04-02.
- Schulman, Henry (May 4, 2012). "Pablo Sandoval - same injury, other hand". The San Francisco Chronicle.
- "Markakis faces surgery for broken hamate bone". MLB. May 31, 2012. Retrieved 2012-05-31.
- "Sox's Beckham fractures wrist bone, out six weeks". Chicago Tribune. April 11, 2013. Retrieved 2013-04-30.
- http://www.cbssports.com/mlb/blog/eye-on-baseball/22903059/mike-zunino-expected-to-miss-six-weeks-with-broken-hamate-bone CBS Sports. July 26, 2013.
- http://www.cbssports.com/mlb/eye-on-baseball/24510564/report-wilson-ramos-needs-surgery-will-miss-4-8-weeks CBS Sports. April 1, 2014.