Table of Contents
Which muscles do spinal nerves from the sacral region of the cord innervate?
Spinal Motor Control. Individual pools of motor neurons in the sacral spinal cord innervate the levator ani, puborectalis, and EAS. A pool of small motor neurons in the ventral horn of the sacral spinal cord at S2, named Onuf’s nucleus, project their axons in the pudendal nerve.
What do the sacral nerves innervate?
In human anatomy, the sacral plexus is a nerve plexus which provides motor and sensory nerves for the posterior thigh, most of the lower leg and foot, and part of the pelvis. It is part of the lumbosacral plexus and emerges from the lumbar vertebrae and sacral vertebrae (L4-S4).
What regions are innervated by nerves of the sacral plexus?
The sacral plexus provides motor and sensory innervation through the following nerves:
- Sciatic Nerve (L4 – S3)
- Pudendal Nerve (ventral divisions of S2 – S4)
- Superior Gluteal Nerve (dorsal divisions of L4 – S1)
- Inferior Gluteal Nerve (dorsal divisions of L5 – S2)
- Nerve to Obturator Internus (ventral divisions of L5 – S2)
What does the spinal cord innervate?
The cervical spinal nerves innervate the muscles and provide sensation for the head, neck, and diaphragm, as well as the upper limbs and back. The lumbar, sacral, and coccygeal nerves combine to form the lumbosacral plexus.
What is the sacral spinal cord?
The sacral spine (sacrum) is located below the lumbar spine and above the tailbone, which is known as the coccyx. Five bones that are fused together make up the triangle-shaped sacrum, and these bones are numbered S-1 to S-5. Each number corresponds with the nerves in that section of the spinal cord.
What does the S1 nerve innervate?
Although considerable controversy still exists, previous work in this field suggests that the L5 nerve root supplies tibialis anterior, extensor hallucis longus, extensor digitorum brevis, and the lateral head of gastrocnemius, while the S1 nerve root innervates the medial head of gastrocnemius, soleus, and abductor …
What nerves are in the sacrum?
Nerves
- Lumbar Plexus.
- Femoral Nerve.
- Obturator Nerve.
- Sciatic Nerve.
- Tibial Nerve.
- Common Fibular Nerve.
- Superficial Fibular Nerve.
- Deep Fibular Nerve.
Is the sacral plexus part of the spinal cord?
Location. The spinal nerves that comprise the sacral plexus emerge from the lateral (side) regions of the spinal cord. Each of these nerves travels through its corresponding spinal foramen (opening) before they join in their various combinations to form the sacral plexus in the back of the pelvis.
Where is the sacral nerve?
The sacral plexus (plexus sacralis) is a nerve plexus that provides motor and sensory nerves for the posterior thigh, most of the lower leg, the entire foot, and part of the pelvis (see the following image). It is part of the larger lumbosacral plexus.
What are sacral nerves?
The sacral plexus is a network of nerves emerging from the lower part of the spine. These nerves provide motor control to and receive sensory information from most of the pelvis and leg. A plexus is a web of nerves that share roots, branches, and functions.