Intercostal nerve

Intercostal nerves

Intercostal nerves (labeled as thoracic nerves) seen in a diagram of the brachial plexus.
Latin	nervi intercostales

The intercostal nerves are part of the somatic nervous system and arise from the anterior divisions of the thoracic spinal nerves from T1 to T11. These nerves are responsible for the innervation of the intercostal muscles, which are crucial for the mechanical aspect of breathing.

Anatomy

The intercostal nerves are the anterior rami of the thoracic spinal nerves. They run along the inferior border of each rib, within the intercostal space, and are accompanied by the intercostal arteries and veins. The nerves provide motor innervation to the intercostal muscles and sensory innervation to the skin and parietal pleura.

Branches

Each intercostal nerve gives off several branches:

• Muscular branches - supply the intercostal muscles.
• Lateral cutaneous branches - pierce the intercostal muscles to supply the skin of the thorax and abdomen.
• Anterior cutaneous branches - supply the skin near the midline of the thorax and abdomen.

Function

The primary function of the intercostal nerves is to facilitate the contraction of the intercostal muscles, which play a vital role in the mechanics of respiration. They also provide sensory feedback from the skin and pleura, contributing to the perception of pain and temperature.

Clinical significance

Intercostal nerve blocks are used in anesthesia to provide pain relief for procedures involving the thorax and upper abdomen. Damage to these nerves can result in loss of sensation or motor function in the areas they supply, leading to conditions such as intercostal neuralgia.

See also

• Thoracic spinal nerve
• Intercostal muscle
• Respiratory system