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Arrows show the vestigial structure called Darwin's tubercle. In the context of human evolution, vestigiality involves those traits occurring in humans that have lost all or most of their original function through evolution. Although structures called vestigial often appear functionless, they may retain lesser functions or develop minor new ones.
In humans, the vermiform appendix is sometimes called a vestigial structure as it has lost much of its ancestral digestive function.. Vestigiality is the retention, during the process of evolution, of genetically determined structures or attributes that have lost some or all of the ancestral function in a given species. [1]
Evolution of the forelimb may be characterized by many trends. The number of digits, their characteristics, as well as the shape and alignment of radius, ulna, and humerus, have had major evolutionary implications.
Such is the case in whales, which have small vestigial bones that appear to be remnants of the leg bones of their ancestors which walked on land. [53] Humans also have vestigial structures, including the ear muscles, the wisdom teeth, the appendix, the tail bone, body hair (including goose bumps), and the semilunar fold in the corner of the eye ...
unstable spinal fracture-dislocation at the thoracolumbar junction: Thoracic Spine Fractures and Dislocations at eMedicine: Hume fracture: A.C. Hume: olecranon fracture with anterior dislocation of radial head: Ronald McRae, Maxx Esser. Practical Fracture Treatment 5th edition, page 187. Elsevier Health Sciences, 2008.
Gamekeeper's thumb and skier's thumb are two similar conditions, both of which involve insufficiency of the ulnar collateral ligament (UCL) of the thumb. The chief difference between these two conditions is that skier's thumb is generally considered to be an acute condition acquired after a fall or similar abduction injury to the metacarpophalangeal (MCP) joint of the thumb, whereas gamekeeper ...
The Bennett fracture is an oblique intraarticular metacarpal fracture dislocation, caused by an axial force directed against the partially flexed metacarpal. This type of compression along the metacarpal bone is often sustained when a person punches a hard object, such as the skull or tibia of an opponent, or a wall. It can also occur as a ...
Examples: The thumb is on the radial side of the hand (the same as saying the lateral side); the ulnar side of the wrist is the side toward the little finger (medial side). Ventral and dorsal , which describe structures derived from the front (ventral) and back (dorsal) of the embryo , before limb rotation.