What Is the Distal Phalanx of the Ring Finger?
The human hand is distinct from other mammalian hands because of the opposable thumb. A condition known as "ape hand" is so-called because the thumb can only move in the same plane as the palm and cannot oppose or move in front of the palm and other fingers. The bones of the hand are known as the phalanges, metacarpals and carpals. There are a total of 27 bones in the hand, and 14 of them are in the fingers.
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The Fingers
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The human hand has five fingers, commonly known as digits. They are numbered one to five, starting with the thumb. Next is the index finger, also known as the pointing finger, followed by the middle finger, ring finger and lastly the little finger. There are numerous names for all the fingers. The little finger is nicknamed the baby finger or pinky. The ring finger is also known as the marriage finger, medical finger, digitus annularis, leech-finger and physician finger. Polydactyly is a condition in which the hand or foot has extra fingers or toes.
Bones
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Fingers or digits are technically known as the phalanges. Each finger is comprised of three bones: the proximal, medial and distal phalanx. The thumb differs from the other fingers in that it only has two phalanges. The phalanges have shapes that are relatively smooth and long. Each phalanx has a base that is concave and a head that is convex. Distal phalanges are the bones that form the tips of the fingers. The distal phalanx of the ring finger is the bone in the tip of the ring finger, which is located between the baby finger and the middle finger. The distal phalanx extends from the tip of the ring finger and ends at the hinge joint where it articulates or moves together with the head of the middle phalanx. The articular surface of the base of the distal phalanx is smaller than the surface of the head of the middle phalanx.
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Joints
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The joints of the finger are known as hinge joints. The hinge joint at the top of the finger, known as the distal interphalangeal (DIP) joint has the head of the proximal phalanx, which is rounded, articulating with the indented, concave surface of the distal phalanx. The proximal interphalangeal (PIP) joint is the hinge joint between the proximal phalanx and the middle phalanx. The metacarpophalangeal (MCP) joint is the hinge joint between the metacarpal bones and the proximal phalanges. A good way to identify the joints is by making a fist and watching your knuckles appear. The top knuckles are at the distal interphalangeal (DIP) joints, the middle knuckles are the proximal interphalangeal (PIP) joints and the base and biggest set of knuckles are the metacarpophlangeal (MCP) joints.
Nerves and Arteries
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There are many arteries and nerves that supply blood as well as sensory and motor control to the fingers of the hand. The arteries that supply blood to the distal phalanx of the ring finger as well as the other distal phalanges, or finger tips, include the deep palmar arterial arch and the proper palmar digital arteries. Nerves that supply the fingers include the common palmar nerve and its branches and the ulnar nerve.
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References
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