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Pisiform
The pisiform bone ( or ), also spelled pisiforme (from the Latin ''pisifomis'', pea-shaped), is a small knobbly, sesamoid bone that is found in the wrist. It forms the ulnar border of the carpal tunnel. Structure The pisiform is a sesamoid bone, with no covering membrane of periosteum. It is the last carpal bone to ossify. The pisiform bone is a small bone found in the proximal row of the wrist ( carpus). It is situated where the ulna joins the wrist, within the tendon of the flexor carpi ulnaris muscle. It only has one side that acts as a joint, articulating with the triquetral bone. It is on a plane anterior to the other carpal bones and is spheroidal in form. The pisiform bone has four surfaces: # The ''dorsal surface'' is smooth and oval, and articulates with the triquetral: this facet approaches the superior, but not the inferior border of the bone. # The ''palmar surface'' is rounded and rough, and gives attachment to the transverse carpal ligament, the flexor carpi ulnari ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carpal Bones
The carpal bones are the eight small bones that make up the wrist (or carpus) that connects the hand to the forearm. The term "carpus" is derived from the Latin carpus and the Greek καρπός (karpós), meaning "wrist". In human anatomy, the main role of the wrist is to facilitate effective positioning of the hand and powerful use of the extensors and flexors of the forearm, and the mobility of individual carpal bones increase the freedom of movements at the wrist.Kingston 2000, pp 126-127 In tetrapods, the carpus is the sole cluster of bones in the wrist between the radius and ulna and the metacarpus. The bones of the carpus do not belong to individual fingers (or toes in quadrupeds), whereas those of the metacarpus do. The corresponding part of the foot is the tarsus. The carpal bones allow the wrist to move and rotate vertically. Structure Bones The eight carpal bones may be conceptually organized as either two transverse rows, or three longitudinal columns. Wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triangular Bone
The triquetral bone (; also called triquetrum, pyramidal, three-faced, and formerly cuneiform bone) is located in the wrist on the medial side of the proximal row of the carpus between the lunate and pisiform bones. It is on the ulnar side of the hand, but does not directly articulate with the ulna, however it is connected and articulate with the ulna through Triangular fibrocartilage discManaster, B. J., Julia Crim "Imaging Anatomy: Musculoskeletal E-Book" Elsevier Health Sciences, 2016, p. 326. and ligament, which forming the part of the ulnocarpal joint capsule. It connects with the pisiform, hamate, and lunate bones. It is the 2nd most commonly fractured carpal bone. Structure The triquetral is one of the eight carpal bones of the hand. It is a three-faced bone found within the proximal row of carpal bones. Situated beneath the pisiform, it is one of the carpal bones that form the carpal arch, within which lies the carpal tunnel. The triquetral bone may be distinguished by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carpal Bones
The carpal bones are the eight small bones that make up the wrist (or carpus) that connects the hand to the forearm. The term "carpus" is derived from the Latin carpus and the Greek καρπός (karpós), meaning "wrist". In human anatomy, the main role of the wrist is to facilitate effective positioning of the hand and powerful use of the extensors and flexors of the forearm, and the mobility of individual carpal bones increase the freedom of movements at the wrist.Kingston 2000, pp 126-127 In tetrapods, the carpus is the sole cluster of bones in the wrist between the radius and ulna and the metacarpus. The bones of the carpus do not belong to individual fingers (or toes in quadrupeds), whereas those of the metacarpus do. The corresponding part of the foot is the tarsus. The carpal bones allow the wrist to move and rotate vertically. Structure Bones The eight carpal bones may be conceptually organized as either two transverse rows, or three longitudinal columns. Wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flexor Carpi Ulnaris Muscle
The flexor carpi ulnaris (FCU) is a muscle of the forearm that flexes and adducts at the wrist joint. Structure Origin The flexor carpi ulnaris has two heads; a humeral head and ulnar head. The humeral head originates from the medial epicondyle of the humerus via the common flexor tendon. The ulnar head originates from the medial margin of the olecranon of the ulnar and the upper two-thirds of the dorsal border of the ulnar by an aponeurosis. Between the two heads passes the ulnar nerve and ulnar artery. Insertion The flexor carpi ulnaris inserts onto the pisiform, hook of the hamate (via the pisohamate ligament) and the anterior surface of the base of the fifth metacarpal (via the pisometacarpal ligament). Action The flexor carpi ulnaris flexes and adducts at the wrist joint. Innervation The flexor carpi ulnaris is innervated by the ulnar nerve. The corresponding spinal nerves are C8 and T1. Tendon The tendon of flexor carpi ulnaris can be seen on the anterior surface ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ulnar Collateral Ligament Of Wrist Joint
The ulnar collateral ligament (internal lateral ligament, ulnar carpal collateral ligament or ulnar collateral ligament of the wrist joint) is a rounded cord, attached above to the end of the styloid process of the ulna The ulna (''pl''. ulnae or ulnas) is a long bone found in the forearm that stretches from the elbow to the smallest finger, and when in anatomical position, is found on the medial side of the forearm. That is, the ulna is on the same side of t ..., and dividing below into two fasciculi, one of which is attached to the medial side of the triquetral bone, the other to the pisiform and flexor retinaculum. References Ligaments of the upper limb {{Portal bar, Anatomy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hamate Bone
The hamate bone (from Latin hamatus, "hooked"), or unciform bone (from Latin '' uncus'', "hook"), Latin os hamatum and occasionally abbreviated as just hamatum, is a bone in the human wrist readily distinguishable by its wedge shape and a hook-like process ("hamulus") projecting from its 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 metacarpals of the little finger and ring finger. Adjacent to the hamate on the ulnar side, and slightly above it, is the pisiform bone. Adjacent on the radial side is the capitate, and proximal is the lunate bone. Surfaces 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transverse Carpal Ligament
The flexor retinaculum (transverse carpal ligament, or anterior annular ligament) is a fibrous band on the palmar side of the hand near the wrist. It arches over the carpal bones of the hands, covering them and forming the carpal tunnel. Structure The flexor retinaculum is a strong, fibrous band that covers the carpal bones on the palmar side of the hand near the wrist. It attaches to the bones near the radius and ulna. On the ulnar side, the flexor retinaculum attaches to the pisiform bone and the hook of the hamate bone. On the radial side, it attaches to the tubercle of the scaphoid bone, and to the medial part of the palmar surface and the ridge of the trapezium bone. The flexor retinaculum is continuous with the palmar carpal ligament, and deeper with the palmar aponeurosis. The ulnar artery and ulnar nerve, and the cutaneous branches of the median and ulnar nerves, pass on top of the flexor retinaculum. On the radial side of the retinaculum is the tendon of the flexor car ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carpal Tunnel
In the human body, the carpal tunnel or carpal canal is the passageway on the palmar side of the wrist that connects the forearm to the hand. The tunnel is bounded by the bones of the wrist and flexor retinaculum from connective tissue. Normally several tendons from the flexor group of forearm muscles and the median nerve pass through it. There are described cases of variable median artery occurrence. When any of the nine long flexor tendons passing through the narrow carpal canal swell or degenerate, the narrowing of the canal may result in the median nerve becoming entrapped or compressed, a common medical condition known as carpal tunnel syndrome (CTS). Structure The carpal bones that make up the wrist form an arch which is convex on the dorsal side of the hand and concave on the palmar side. The groove on the palmar side, the ''sulcus carpi'', is covered by the flexor retinaculum, a sheath of tough connective tissue, thus forming the carpal tunnel. On the side ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abductor Digiti Quinti Muscle (hand)
In human anatomy, the abductor digiti minimi (abductor minimi digiti, abductor digiti quinti, ADM) is a skeletal muscle situated on the ulnar border of the palm of the hand. It forms the ulnar border of the palm and its spindle-like shape defines the hypothenar eminence of the palm together with the skin, connective tissue, and fat surrounding it. Its main function is to pull the little finger away from the other fingers (i.e. abduction). Structure The abductor digiti minimi arises from the pisiform bone, the pisohamate ligament, and the flexor retinaculum. Its distal tendon ends in three slips that are inserted into the ulnopalmar margin of the proximal phalanx, the palmar plate of the metacarpophalangeal joint, and the sesamoid bone when present. Some fibers insert into the finger's dorsal aponeurosis, which is why the muscle acts similar to a dorsal interosseus muscle. Additionally, the ulnar-most portion of the tendon inserts into the little finger's digital cord, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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