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A dermatome is an area of skin that is mainly supplied by a single spinal nerve.〔(【引用サイトリンク】url=http://emedicine.medscape.com/article/1878388-overview )〕 There are 8 cervical nerves (C1 being an exception with no dermatome), 12 thoracic nerves, 5 lumbar nerves and 5 sacral nerves. Each of these nerves relays sensation (including pain) from a particular region of skin to the brain. A dermatome also refers to the part of an embryonic somite. Along the thorax and abdomen the dermatomes are like a stack of discs forming a human, each supplied by a different spinal nerve. Along the arms and the legs, the pattern is different: the dermatomes run longitudinally along the limbs. Although the general pattern is similar in all people, the precise areas of innervation are as unique to an individual as fingerprints. A similar area innervated by peripheral nerves is called a peripheral nerve field. == Clinical significance == A dermatome is an area of skin supplied by sensory neurons that arise from a spinal nerve ganglion. Symptoms that follow a dermatome (e.g. like pain or a rash) may indicate a pathology that involves the related nerve root. Examples include somatic dysfunction of the spine or viral infection. Referred pain usually involves a specific, "referred" location so is not associated with a dermatome. Viruses that lie dormant in nerve ganglia (e.g. varicella zoster virus, which causes both chickenpox and herpes zoster commonly shingles), often cause either pain, rash or both in a pattern defined by a dermatome. However, the symptoms may not appear across the entire dermatome. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Dermatome (anatomy)」の詳細全文を読む スポンサード リンク
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