Dermatomes 皮節

The skin over the entire body is supplied by somatic sensory neurons that carry nerve impulses from the skin into the spinal cord and brain.

整個身體的皮膚由體感覺神經元供應，這些神經元將神經衝動從皮膚傳送到脊髓和大腦。

Each spinal nerve contains sensory neurons that serve a specific, predictable segment of the body. 每根脊椎神經都包含感覺神經元，服務於身體特定的、可預測的部位。

One of the cranial nerves, the trigeminal(V) nerve, serves most of the skin of the face and scalp. 腦神經之一，三叉神經 (V)，服務於臉部和頭皮的大部分皮膚。

The area of the skin that provides sensory input to the CNS via one pair of spinal nerves or the trigeminal (V) nerve is called a dermatome (DER-ma-tõm; derma-

= skin; -tome = thin segment) (Figure 13.7). 透過一對脊椎神經或三叉神經 (V) 神經向中樞神經系統提供感覺輸入的皮膚區域稱為皮節 (DER-ma-tõm；derma-

= 皮膚； -tome = 薄段）（圖 13.7）。

The nerve supply in adjacent dermatomes overlaps somewhat. 相鄰皮區的神經供應有些重疊。

Knowing which spinal cord segments supply each dermatome makes it possible to locate damaged regions of the spinal cord. 了解每個皮節的脊髓節段可以定位脊髓的受損區域。

If the skin in a particular region is stimulated but the sensation is not perceived, the nerves supplying that dermatome are probably damaged. 如果特定區域的皮膚受到刺激但感覺不到，則供應皮區的神經可能已受損。

In regions where the overlap is con-siderable, little loss of sensation may result if only one of the nerves supplying the dermatome is damaged. 在重疊相當大的區域，如果只有一條供應皮節的神經受損，可能會導致很少的感覺喪失。

Information about the innerva-tion patterns of spinal nerves can also be used therapeutically. 有關脊椎神經支配模式的資訊也可用於治療。

Cutting posterior roots or infusing local anesthetics can block pain either permanently or transiently. 切斷後根或註入局部麻醉劑可以永久或暫時緩解疼痛。

Because dermatomes overlap, deliberate production of a region of complete anesthesia may require that at least three adjacent spinal nerves be cut or blocked by an anesthetic drug. 由於皮區重疊，故意產生完全麻醉的區域可能需要用麻醉藥物切斷或阻斷至少三個相鄰的脊椎神經。

Source:

Tortora’s Principles of Anatomy& Physiology, Global Edition, Gerard J. Tortora and Bryan H. Derrickson