The cervical (C1-C4) and brachial (C5-T1) plexuses innervate the muscles and skin of the neck, shoulder, arm, and hand. They are responsible for motor control and sensation in these areas. The C1-C4 plexus primarily innervates the muscles of the neck and head, while the brachial plexus primarily innervates the upper extremities.
The major plexuses of the spinal cord are: Cervical Plexus (C1–C4) – neck & diaphragm Brachial Plexus (C5–T1) – upper limbs Lumbar Plexus (L1–L4) – abdomen & thigh Sacral Plexus (L4–S4) – leg & foot Coccygeal Plexus (S4–Co1) – coccyx
The ventral rami of spinal nerves C1-T1 form the cervical plexus, serving the head, neck, and diaphragm. T12-S4 form the lumbosacral plexus, serving the lower limbs and pelvic region. These plexuses distribute nerve fibers to various muscles and skin areas, allowing for coordinated movement and sensation in these regions.
The brachial plexus primarily comprises the ventral rami of spinal nerves C5 to T1, but there are several nerves that are not part of it. Notably, the intercostal nerves, which arise from the thoracic spinal nerves (T1 to T11), and the phrenic nerve, which originates from C3 to C5, are not included in the brachial plexus. Additionally, the cranial nerves, such as the vagus nerve (cranial nerve X), also do not belong to this plexus.
The brachial plexus contains fibers from the ventral rami of the cervical spinal nerves (C5-C8) and the first thoracic spinal nerve (T1). These fibers combine to form the nerves that innervate the upper limb.
The pectoralis minor muscle is innervated by the medial pectoral nerve, which arises from the medial cord of the brachial plexus (C8-T1).
motor and sensory needs of the body
The major plexuses of the spinal cord are: Cervical Plexus (C1–C4) – neck & diaphragm Brachial Plexus (C5–T1) – upper limbs Lumbar Plexus (L1–L4) – abdomen & thigh Sacral Plexus (L4–S4) – leg & foot Coccygeal Plexus (S4–Co1) – coccyx
Brachial plexus (C5-T1)
The ventral rami of spinal nerves C5 to T1 contribute fibers to the brachial plexus. This plexus is responsible for innervating the muscles and skin of the shoulder, arm, and parts of the hand. It plays a crucial role in motor and sensory functions of the upper limb.
The brachial plexus is formed by the spinal nerves C5-T1, while the lumbosacral plexus is formed by the spinal nerves L1-S4. These plexuses are networks of nerves that supply motor and sensory innervation to the upper and lower limbs, respectively.
Except for T2-T12, all ventral rami branch and join one another lateral to the vertebral column, forming complicated interlacing nerve networks called nerve plexuses. Nerve plexuses occur in the cervical, brachial, lumbar, and sacral regions and primarily serve the limbs (MarieB, 2010 8th ed. pp. 502)
what major nerves arise from the coccygeal plexus
The ventral rami of spinal nerves C1-T1 form the cervical plexus, serving the head, neck, and diaphragm. T12-S4 form the lumbosacral plexus, serving the lower limbs and pelvic region. These plexuses distribute nerve fibers to various muscles and skin areas, allowing for coordinated movement and sensation in these regions.
The median nerve is a member of the brachial plexus. It is formed by contributions from the lateral and medial cords of the brachial plexus, primarily from spinal nerve roots C6, C7, C8, and T1.
The root nerves C5-T1 make up an arrangement called the brachial plexus. This plexus supplies all the musles of the upper limb. There is no one muslce supplies by all of these root nerves.
The brachial plexus primarily comprises the ventral rami of spinal nerves C5 to T1, but there are several nerves that are not part of it. Notably, the intercostal nerves, which arise from the thoracic spinal nerves (T1 to T11), and the phrenic nerve, which originates from C3 to C5, are not included in the brachial plexus. Additionally, the cranial nerves, such as the vagus nerve (cranial nerve X), also do not belong to this plexus.
plexuses