Search results
Results from the WOW.Com Content Network
The thumb is the first digit of the hand, next to the index finger. [A] When a person is standing in the medical anatomical position (where the palm is facing to the front), the thumb is the outermost digit. The Medical Latin English noun for thumb is pollex (compare hallux for big toe), and the corresponding adjective for thumb is pollical.
Left hand shown with thumb on left. The metacarpals form a transverse arch to which the rigid row of distal carpal bones are fixed. The peripheral metacarpals (those of the thumb and little finger) form the sides of the cup of the palmar gutter and as they are brought together they deepen this concavity.
The first metacarpal bone is short and thick with a shaft thicker and broader than those of the other metacarpal bones. Its narrow shaft connects its widened base and rounded head; the former consisting of a thick cortical bone surrounding the open medullary canal; the latter two consisting of cancellous bone surrounded by a thin cortical shell.
The carpometacarpal (CMC) joints are five joints in the wrist that articulate the distal row of carpal bones and the proximal bases of the five metacarpal bones.. The CMC joint of the thumb or the first CMC joint, also known as the trapeziometacarpal (TMC) joint, differs significantly from the other four CMC joints and is therefore described separately.
The metacarpal bone of the index finger has two centres of ossification: a primary centre in the shaft and a secondary centre in the head. This contrasts to the first metacarpal bone where the secondary centre is found in the base. The ossification process begins in the shaft during prenatal life, and in the head between 11th and 22nd months. [4]
The trapezium is an irregular-shaped carpal bone found within the hand. The trapezium is found within the distal row of carpal bones, and is directly adjacent to the metacarpal bone of the thumb. On its ulnar surface are found the trapezoid and scaphoid bones. [1]: 708
Three phalanges are present on each finger and toe, with the exception of the thumb and big toe, which possess only two. The middle and far phalanges of the fourth and [citation needed] fifth toes are often fused together (symphalangism). [1] [2] The phalanges of the hand are commonly known as the finger bones. The phalanges of the foot differ ...
The triquetral bone (/ t r aɪ ˈ k w ɛ t r əl,-ˈ k w iː-/; 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.