Sciatic nerve pain are felt along the sciatic nerve is referred to as sciatica. The sciatic nerve is the largest single nerve in your body. It runs from each side of the lower spine, through to deep in the buttock into the back of the thigh and all the way down to your toes. It relays messages and connects your spinal cord with the leg and foot muscles.
Nerves act like power cables. These power cables control all your bodies movement and communication such as feeling to the skin and muscles, this includes touch, temperature and a variety of other feelings.
The Sciatic Nerve
The Sciatic nerve is a bundle of wires (nerve roots) that run out of the spinal cord at the Lumbar and Sacral vertebrae. The sciatic nerve is a very thick branch of nerves that come from the L4 to S3 nerve roots. Its like the power cables that run out of your back and into your leg. The nerve originates in the lower spine as nerve roots exit the spinal cord (through gaps in the bones at the back of the spine), and extends all the way down the back of the leg to the toes.
The sciatic nerve is the largest and longest single nerve in the human body, about as big around as a man’s thumb. The sciatic nerve is actually made up of five nerves. It is formed on the right and left hand side of the lower spine by the combination of the fourth and fifth lumbar nerves and the first three nerves in the sacral spine. (L4- S3)
The five nerves group together on the front surface of the piriformis muscle (at the back of the buttock) and become one large nerve, the sciatic nerve. This nerve then travels down the back of each leg, branching out to provide motor and sensory functions to specific regions of the leg and foot.
In the lower thigh/above the back of the knee, the sciatic nerve divides into two nerves, the tibial and peroneal nerves, which innervate different parts of the lower leg:
- Peroneal nerves. The peroneal nerves travel laterally (sideways) along the outer part of the knee and down into the upper foot.
- Tibial nerves. The tibial nerves continue to travel downward toward the feet and innervate the heel and sole of the foot.
Sciatic Nerve Pain (Sciatica)
Sciatica is a condition where there is compression or irritation on the sciatic nerve. Usually only one side is affected and pain runs from the right or left side of the lower back to the buttock, down the back of the thigh, into the calf all the way to the toes.
Any problem in the lower spine can affect one of the nerves that feeds into the sciatic nerve, causing pain to radiate along that part of the nerve.
The sciatic nerve supplies sensation and strength to the leg as well as the reflexes of the leg. It connects the spinal cord with the outside of the thigh, the hamstring muscles in the back of the thighs, and muscles in the lower leg and feet. As such, when the sciatic nerve is impaired, it can lead to muscle weakness and/or numbness or tingling in the leg, ankle, foot, and/or toes.
Because of the different nerve pathways, symptoms of sciatic nerve pain may present in different parts of the leg or foot depending on where the nerve is affected.
Where does the nerve pain come from?
This irritation or compression on the sciatic nerve can be causes by various structures that runs over and along the nerve pathway.
When these power cables gets compressed, it stimulates the nerve at the site where the compression is taking place, and the impulse will run to the area where the nerve supplies the muscle or skin. Each nerve root runs to a different area.
If the compression on the nerve roots of is only on one strand of nerve root (L4-S3) neurons. Only the area where that nerve root runs to will produce symptoms. In our experience usually one or two nerve roots are affected. But when the compression is so much that the whole leg area from L4 to S3 are affected, you must see a medical practitioner as soon as possible.
Sciatic nerve Compression
This is the result of a nerve irritation that gets worse. During this phase the nerves that supply the power cables to the legs can become totally compressed and cause constant burning or sharp pains. Constant irritation on the tissue surrounding the nerve can leave you with pain that does not ease, no matter what you do.
When the nerve is totally compressed, it may cut off the signal from your leg to your brain (Your toes sends the message, but it gets cut off at the point of compression). This will feel more like constant burning or sharp shooting pain. The pain will progress from pins & needles to numbness and eventually you won’t be able to control the movements in your hip, thigh, knee or foot. This pain tends to hang around a lot longer and stays for hours until (if) the compression is relieved.
The more the compression, the more distorted the feeling will be, until the nerve is totally compressed and no message can go to the brain, then your skin goes numb. If the compression on the nerve is not relieved, there could be permanent damage to the nerves.
The compression on a nerve prevents feedback signals to your brain which causes clumsiness and weakness, which will make you feel like you have lost power. Muscle weakness is a very clear sign of nerve compression.
Sciatic Nerve Irritation
The friction between the nerve, muscle, joint and ligament irritates the power cables and cause them to swell. This causes a sharp sudden burning or electrical shock type pain to run down the leg. The Sciatic nerve is irritated at the point of irritation, but you feel pain all the way down the nerve.
One of the first signs of irritation is that the discomfort progresses to pain, leading to Pins & Needles as it gets worse. Initially the nerve pain only comes on occasionally and relieves after a few minutes. This type of sudden sharp pain comes & goes away, only only to be brought on when moving into a specific movement or position.
Generally it starts at the Lower back and progressively moves downwards towards your butt and even into your toes. You will notice that it develops slowly and starts off being worse at night or early in the morning.
How does Sciatic nerve pain feel?
Sciatic nerve pain feels very different to other types of pain. Nerve pain is a very distinctive pain, unlike anything you have ever experienced. It can only be described as unbearable and excruciating.
This can be a variety of abnormal feelings like: Pins & needles, numbness, burning tingling, weakness, electrical shock traveling from the lowerback to the hip, leg, thigh, calf into the toes. This type of pain from a nerve is also known as neuropathic pain or neuralgia.
Signs of Sciatica
- Burning pain
- Pins & Needles
- Sharp stabbing, shooting pain
- Electrical shock pain
- Unable to control movement
- Dead feeling over skin
- Unable to do movements
- Dead feeling over skin
- Unable to control bladder
- Pain when sitting on the toilet and bearing down
- Fainting/ Dizziness
- Skin colour changes
- Change in consciousness, or mental status
Test for Sciatic nerve damage
If you suffer from any of these you should give us a call:
- Difficult to distinguish between Light touch (cotton wool stroked over the skin) and deep touch (compressing the skin in the area)
- Struggle to distinguish between Sharp touch (skin pierced with a toothpick) Blunt (press with the back of a pencil)
- Temperature: Difficult to distinguish between hot and cold temperatures.
- Pins & needles when touching something
- Numbness (“Dead” feeling over skin)
This is a test where needles are inserted into the muscles that the nerve supplies. It measures the electrical activity produced by these muscles. The electrical activity of the nerve will be tested when you contract and relax your muscles. This test can determine if there is any nerve damage.
This test is performed by a Neurologist and is often referred to as ‘Nerve conduction studies’. It examines both the sensory (feeling) and the motor (ability to contract or relax muscles) function of the nerve. This test is able to show the weakening of the impulse traveling through the nerve. It is considered abnormal when the impulse travels slower, and weakens between 2 points (conduction velocity).
An ultrasound can visualize the structures and the space around the nerve as well as swelling of the tendons, muscles, joints etc. We will compare the uninjured side to the painful side.