The sciatic nerve starts in the lower back and extends down the back of the lower body, but if the nerve root is irritated where it exits the lumbar spine, or anywhere along its pathway, symptoms may be widespread throughout the lower body.
True sciatica affects the lower body and lower extremities due to nerve compression. The sciatic nerve doesn't reach the arms and hands, so if nerve pain is felt in the arms and hands, it’s likely that a nerve is compressed in the cervical spine.
Sciatic nerve irritation signals the need for treatment to prevent permanent damage.
Sciatica and the Arms and Hands
The sciatic nerve starts in the lumbar spine and extends down the back of the lower body through the hip, pelvis, buttock, leg, and foot.
The sciatic nerve is the largest in the body and is a mixed nerve containing both sensory and motor fibers. 
Because nerves of the cervical spine (C5-C8) exit the spinal cord and project directly into the arms and hands, the nerves control movement and touch.
The cervical spine (neck) has to support the weight of the head and the neck's range of motion, and if a cervical nerve root is exposed to uneven pressure due to disc degeneration, bone spurs, or arthritis, arm, hand, and/or shoulder pain is common.
Sensations of numbness and tingling (pins and needles), weakness, and loss of dexterity in the hands are additional signs of nerve compression in the upper spine.
In addition, a localized arm issue can also cause radiating pain in the arms and hands. Carpal tunnel syndrome, for example, is associated with arm and hand pain.
So patients experiencing nerve-related symptoms in the upper body need professional assessment to determine the location of the compressed nerve root, its underlying cause, and to customize a treatment plan around cause, severity, a patient's symptoms, and treatment goals.
Just as nerve roots compressed in the upper spine will largely affect the upper body, nerve root compression in the lower spine affects the lower body.
Diagnosing issues related to nerve compression isn't always easy. When symptoms develop far from the site of nerve irritation, it can be difficult to determine the cause.
It's important to recognize symptoms of sciatica so causes can be explored and treatment options can be discussed.
Symptoms of sciatic nerve root irritation include radiating pain that most often affects one side of the lower body. Commonly felt down the left side, it can also involve the right side of the body, and in rare cases, the left and right side can be affected. Leg, knee, and foot pain are common.
Pain can range from a dull ache to sharp shooting pain and/or electric shock-like sensations. Pins and needle sensations are common in the foot and/or calf. Difficulty moving and lifting the foot and wiggling the toes is also common, as is the feeling of pressure on the affected foot.
Pain can worsen with sitting for long periods due to weight and pressure on the lumbar spine. When back pain is occurring, the body tries to compensate by adjusting movement to reduce pain, and this can also lead to the development of unhealthy movement patterns and poor posture.
The health of the spine is shaped by a number of factors, and postural health is one, so if back and lower body pain is contributing to unhealthy posture, it needs to be addressed before further negative effects become established.
If symptoms of sciatica are noticed, it's time to isolate the underlying cause of the sciatic nerve compression so the next best steps can be determined.
The main cause of sciatica pain is disc herniation. The spine's vertebrae (bones) are separated by an intervertebral disc, and the discs give the spine flexibility, structure, cushioning during movement to prevent friction, and shock absorption.
Because of the many roles of the discs and their avascular nature, they are often the first spinal structures to experience degenerative changes, and when this happens, a disc can change shape, and become a bulging and/or herniated disc.
A disc herniates when its inner nucleus pushes through a tear in the disc's outer layer and projects into the space around the disc. If this happens in the lumbar spine, and the sciatic nerve is pinched, it can cause sciatic nerve pain throughout the lower body.
Degenerative disc disease is a contributing factor in the development of a number of spinal conditions and issues.
Spinal stenosis can also cause nerve root compression because the spinal canal cord narrows, applying pressure to the spinal cord in the affected section, and if lumbar stenosis develops, it can mean less space for the sciatic nerve.
Piriformis syndrome can cause sciatica if the buttock's piriformis muscles spasms and compresses the sciatic nerve along its pathway.
An underlying spinal condition like scoliosis can also cause sciatica if the spine's unnatural curve and rotation develops in the lumbar spine and interferes with the sciatic nerve.
Determining the cause of the radiating sciatic nerve pain is the first step to customizing a treatment plan for long-term improvement.
There is an important distinction between addressing sciatica symptoms and the underlying cause for long-term symptom relief.
Solely addressing symptoms offers short-term pain relief through medication and temporary solutions such as hot/cold therapy, but if the underlying cause of the sciatic nerve irritation isn't determined and addressed, potential for long-term improvement is limited.
Treatment options are shaped around a number of factors including cause, severity, and symptoms.
If disc herniation is the issue, improvements to disc health are necessary and can include a number of conservative treatments including physical therapy, activity modification, lifestyle guidance, and in severe cases, surgical intervention. The disc's shape will need to be restored so pressure is taken off the sciatic nerve.
If the spinal canal has narrowed and is compressing the spinal cord within, space needs to be opened up within the spine to reduce inflammation and pressure on the spinal cord. First-line treatments for lumbar stenosis can include physical therapy, targeted stretches, and anti-inflammatory medications.
Treatment for piriformis syndrome focuses on the piriformis muscle itself through targeted physical therapy, gentle stretching, and activity modification.
If sciatica symptoms are caused by lumbar scoliosis, the spine's unnatural curve and rotation need to be impacted on a structural level so uneven pressure on the sciatic nerve is reduced, and this can involve scoliosis-specific chiropractic care and physical therapy so the spine's unnatural curve is reduced, and surrounding muscle balance and strength are improved for more support.
Nerves need space to function, and if there is a loss of space and pressure is applied to the sciatic nerve, sciatic nerve pain can develop.
Sciatica can affect the lower body including the lower back, hip, buttock, leg, and foot, but because the sciatic nerve starts in the lumbar spine and extends down the back of the lower body, its effects are isolated to the lower body and don't reach the arms and hands.
If a nerve is compressed in the cervical spine, however, radiating pain in the arms and hands is a sign that assessment is needed to determine the cause and make informed treatment choices moving forward.
Here at the CLEAR Scoliosis Institute, the goal is always improving a patient's overall quality of life, so if you are experiencing leg pain, muscle weakness, knee pain, and strange sensations such as pins and needles throughout the lower body, treatment that reduces pressure on the sciatic nerve may offer long-term symptom relief.
Many patients experiencing sciatica pain find relief from conservative treatment involving a comprehensive evaluation to determine the underlying cause, lifestyle guidance with activity modifications where necessary, targeted physical therapy, stretches, hot/cold therapy, and anti-inflammatory medications.
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