Overview

Sacral nerves are a part of the human peripheral nervous system, emerging from the sacral region of the spinal cord. They play a critical role in transmitting sensory information and controlling motor functions in the pelvic region, buttocks, groin, and lower limbs, including the bladder, bowel, and sexual functions.

A network formed by the nerves of the lumbosacral trunk and sacral nerves together is known as the sacral plexus. The sacral plexus is located at the pelvic wall's posterior and anterior to the piriformis muscle. The plexus also gives off different branches, such as anterior, posterior, and terminal branches.

These branches help process the information provided and movement of the posterior thigh, lower leg, complete foot, and a part of the pelvis. These nerves emerge from the lower part of the spine, providing motor control. They receive sensory information from the pelvis and leg. These nerves cover the maximum portion of the body.

Sacral Plexus - Sacral Nerves S1 through S4 and lumbar spinal nerves L4 and L5 form the sacral plexus. Multiple combinations of these nerves divide into the branches of the sacral plexus. The lumbosacral trunk is connected with sacral spinal nerves S1, S2, S3, and S4 to form the sacral plexus. A connection between the anterior motor root and posterior sensory root is observed at each spine level.

- S1 Nerve: It innervates the muscles that control plantar flexion of the ankle joint (pointing your toes downward). It also plays a role in knee flexion and hip extension. It also provides sensation to the outer side (lateral) and back (posterior) of the lower leg and the sole of the foot.
- S2 Nerve: It innervates muscles involved in hip extension and knee flexion. It also plays a role in some pelvic floor muscles. It also provides sensory innervation to the back of the thigh and the back of the knee.
- S3 Nerve: It contributes to the innervation of muscles involved in hip extension and knee flexion. It also provides sensation to the skin over the back of the thigh and part of the buttocks.
- S4 Nerve: It is primarily associated with controlling some pelvic floor muscles, including the S4 Nerve: It is primarily associated with controlling some pelvic floor muscles, including the anal sphincter. It may provide sensory input to the area around the perianal region and the perineum.
- Ventral and Posterior Portions - Each spinal nerve is divided into ventral and posterior portions for motor and sensory functions. The sacral plexus divides into various nerves, such as the superior gluteal nerve, inferior gluteal nerve, sciatic nerve, common fibular nerve, posterior femoral cutaneous nerve, and many other similar forms of nerves.

The spinal nerves of the sacral plexus emerge from the lateral regions of the spinal cord. These nerves then travel through their corresponding openings before forming a sacral plexus in the back of the pelvis. During this procedure, some nerves remain in the pelvic region while some travel down through the leg. Few nerves exit the pelvic area through the sciatic foramen and travel down the leg.

The structure of the sacral plexus has several different variations. No medical issues are caused due to the variations of the sacral plexus, but they can be observed during a surgical procedure. The plexus may be divided into the higher or lower pelvic region. Studies also show that sacral nerves are divided into different branches, such as the pudendal nerve, the quadratus femoris muscle nerve, the obturator internus muscle, and the nerve to the piriformis muscle. Different sections form all these nerves and have other functions as well.

[caption id="attachment_22818" align="alignnone" width="1000"] Anatomy of Sacral Nerves[/caption]

Functions of Sacral Nerves

- Nerve Stimulation - Sacral nerves function majorly in the pelvic region and the legs. Several muscles feel nerve stimulation with the help of the branches of the sacral plexus. The sensory messages sent by the pelvic region's skin, joints, structures, and legs are also received by units of the sacral plexus.
- Messaging to Motor Nerves - Its motor nerves receive the messages from the brain's motor area. The message is then forwarded to the front column of the spine, sacral plexus, and its motor nerve branches for smooth muscle movement. Motor nerves of the sacral plexus include different types of nerves, such as the superior gluteal nerve, inferior gluteal nerve, pudendal nerve, and sciatic nerve.
- Messaging to the Sensory Fibres - The skin, joints, and muscles send nerve messages to the sensory fibres. These messages are then forwarded to the spine's upper direction and then to the back column of the spine. The messages then travel to the brain's sensory regions to make an individual aware of different sensations. These sensory nerves include other nerves, such as the posterior femoral cutaneous, sciatic, and pudendal nerves.

Treatment of Sacral Nerves

The sacral nerves or a part of the sacral plexus can be damaged due to different tragic conditions such as other types of diseases, traumatic damage, neuropathy, infection, injury, or fatal medical issues such as cancer. The affected individual can recognise the problem by symptoms such as pain and weakness in the things or pelvic region. The problem can be resolved by carrying out different types of steps, such as:

- Treatment of an underlying medical issue – Identifying the cause of the medical problem and treating it accordingly helps to eliminate a medical disorder with greater ease. Hence, identifying the nerve disorders helps identify the medications and preventive measures to cure the problem. The method also helps to prevent the issue and avoid its relapsing.
- Physical therapy – Different physical and occupational therapies help the affected individual gain strength and senses while healing from sacral nerve disease. The method is also helpful to allow one to recover from damaged nerves due to an accident or external injury. The therapy also helps the affected individual walk properly and feel proper sensation in the legs.
- Medications - Prescription medications may be used to manage symptoms such as pain or bladder dysfunction.
- Lifestyle Modifications - Dietary changes, fluid management, and pelvic floor exercises can effectively manage certain sacral nerve-related conditions.
- Surgery: In severe cases or when conservative treatments fail, surgical procedures may be considered to address specific issues such as nerve compression or structural abnormalities.
- Nerve Blocks: Injections of medication or anaesthetic around the sacral nerves to relieve pain or dysfunction.
- Alternative Therapies: Complementary approaches such as acupuncture or biofeedback may be explored for symptom management.
- Use of neurotransmitter- Installation of a neurotransmitter in the buttock region is also one of the treatment options for damaged sacral nerves. The device is similar to a pacemaker and is placed under the skin with the help of a surgical procedure.

When to consult a Doctor

Timely medical intervention can help cure many of these ailments or help in managing them. You can also get in touch with the expert Neurology doctors at Narayana Healthcare based in your city to get immediate attention and medical support to treat brain conditions, neurological disorders or any other health concern.

Conclusion

Sacral nerves are a part of the sacral plexus found in the lower region of the back. These nerves are helpful for proper movement of the lower area of the body. Damage to these nerves can make one lose sensation in the lower body. Still, it can be recovered with the help of different types of medical procedures and other physical therapies.

Reference Links

- https://www.narayanahealth.org/blog/lumbar-spinal-stenosis-causes-symptoms-and-treatment-options/
- https://www.verywellhealth.com/sacral-plexus-anatomy-4689205