The hand is a delicate organ with capacity for powerful grip functions, but also for fine well coordinated motor movements. The hand is also a sense organ providing a sensory feedback necessary for control of motor activities.

Besides protective sensibility, providing response to nociceptive and temperature stimuli, the hand has a tactile discriminative function making possible detection of textures and shapes.

Hand sensation is a prerequisite for adequate hand function, and any impairment of hand sensibility will have serious consequences for hand function.

Hand sensation is based on a complex interplay between mechano-receptors and free nerve endings in the glabrous skin of the fingers and the somatosensory cortex of the brain.

In the fingertips there are various types of mechanoreceptors responding to pressure, vibration or stretching. Long term exposure to vibration may induce damage to the mechanoreceptors as well as the terminal nerve fibers.

In metabolic neuropathy, such as diabetes, there may be structural and functional alterations in cells and fibers in the nerve trunk, and the microvessels of the nerve may also be altered.

Conceptual illustration of the Somatotopic
Map in the Brain
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