One of the causes of lower back pain is pressure on the sciatic nerve. The roots that make up the sciatic nerve can be squeezed by a protruding disc (intervertebral disc herniation). Sometimes the sciatic nerve is compressed by the piriformis muscle, Causes a set of symptoms called piriformis syndrome.
But is there a difference between these two?
In this article, we will examine the differences between sciatica (Sciatic nerve pain) and piriformis syndrome.
The human lumbar spine has five vertebrae, called lumbar vertebrae, which are named as follows:
L1; L2; L3; L4; L5
The sciatic nerve trunk is formed by the joining of two lumbar spinal roots and three sacral spinal roots (Three roots that protrude from the sacral vertebrae which are below the lumbar vertebrae).
Between the two vertebrae is a flexible and cartilaginous piece called the intervertebral disc, which prevents abrasion of two adjacent bones and they also play the role of shock absorbers. Nerve roots (separated from the spinal cord) emerge from the spaces between the vertebrae. These spinal roots provide the sensation and movement of our lower limbs, the muscles of the buttocks, thighs, thighs and toes on both sides.
When these roots come out of the spine, they connect to each other and form the nerve trunk. It is the nerve trunk that extends to our limbs and provides the sensation and movement of all the components of our legs.
The sciatic nerve is the longest nerve in the human body, which is formed by the connection of nerve roots in the lumbar region.
And after connecting the roots and forming the trunk of the sciatic nerve, it moves from the lower back and the back of the pear-shaped muscle called the piriformis muscle to the buttocks, the back of the thigh and the back of the knee, so the sciatic nerve is responsible for the sensation and movement of the buttocks, back of the thighs to the soles of the feet and under the toes.
The main cause of sciatica?
What people call sciatica is actually pain that occurs due to pressure on the spinal roots that make up the trunk of the sciatic nerve in the lower back, and sciatica has two main causes:
- Intervertebral disc protrusion or disc herniation
- Degenerative changes of the vertebrae
- Intervertebral disc protrusion or herniated disc:
Disc problems are more common at a younger age and among young people. The central part of the intervertebral discs is jelly-like. There is a tight circle around the disc, with excessive pressure on the vertebrae, such as when lifting heavy objects, the central part and the jelly-like core of a disc, pushes against the tight ring around the disc and pushes out. This displacement of the disc from a normal location is called a herniated disc.
The protruding disc can put pressure on the spinal roots that make up the sciatic nerve trunk, causing inflammation of the nerves and eventually spreading pain along the sciatic nerve pathway, which is from the lower back and buttocks to the soles of the feet.
Other symptoms of sciatica include:
- Tingling in the path of the sciatic nerve
- Muscle weakness
- Inability to move the toes up (For example, shooting)
- Degenerative changes of the vertebrae:
With age, the jelly-like core of the disc loses its flexibility and water and hardens. Gradually, the height of the disc decreases due to the constant movements of the spine, and the so-called strength of the disc decreases.
The bones adjacent to the disc try to increase the strength of the area by producing extra bony appendages, Osteoarthritis of the joints between the vertebrae also occurs gradually. These bony appendages can put pressure on the spinal roots that make up the sciatic nerve trunk. The main cause of sciatica which is the above characteristics, is the same in elderly too.
What are the symptoms of sciatic nerve pain or sciatic pain?
Symptoms of sciatic nerve pain or sciatic pain include:
- Lower back pain that spreads to the buttocks and back of the thighs, behind the knees, behind the legs, soles of the feet, and under the toes and has a shooting pain (this type of pain is called radicular pain).
- Tingling sensation in the movement of sciatic nerve from the lower back and buttocks and back of the thigh to the sole of the foot
- Feeling of heaviness or muscle cramps in the sciatic nerve
- Inability to bend the toes upwards
- If the pressure continues, the leg muscles will become thinner
In both cases above, skeletal changes are seen on diagnostic imaging, such as MRI or CT scans.
What is piriformis syndrome?
We said that the trunk of the sciatic nerve passes from the back and sometimes through the pear-shaped muscle of the piriformis. This small muscle is located deep in the buttocks and in the pelvis, and spasms or contractions of this muscle put pressure on the sciatica. Piriformis causes you to twist your thigh out of the pelvic joint or away from the axis of your body.
Piriformis contractions or pelvic injuries and bleeding inside the piriformis muscle cause pressure on the sciatic nerve.
Symptoms in piriformis syndrome
Symptoms of piriformis syndrome include:
- Chronic and deep pain that mainly affects the lower back and pelvis and sometimes the buttocks and rarely the upper thighs.
- Pain that is exacerbated by prolonged sitting.
- Pain in the morning when getting out of bed
- Exacerbation of pain with defecation(??)
- Pain intensifies by rotating into the thigh.
- Pain sometimes pierces the penis.(??)
In piriformis syndrome, when affected person is lying on his back and we lift his whole lower limb without bending the knee, He feels pain in the back of the pelvis and buttocks.
If the patient’s thigh is rotated inwards while the patient is lying on his back, the pain will intensify.
When a person is sitting on the edge of a bed or the edge of a chair with their legs dangling, raising the leg without bending the knee will aggravate the pain.
The difference between sciatica (sciatic nerve pain) and piriformis syndrome
So now we can easily tell the difference between sciatica and piriformis syndrome.
Although the two may be similar in some clinical signs (such as hip and lower back and upper back pain),but they will have some differences:
- Unlike sciatica, pain in piriformis Syndrome does not spread to the back of the thighs, the back of the knee, or the elbows and soles of the feet and toes.
- MRI of patients with piriformis syndrome will not show any discs between the elderly vertebrae and degenerative changes despite the pain.
- Intra-articular injections, such as those useful in degenerative changes and pressure on the sciatic nerve, will not play a role in piriformis syndrome.
Similar symptoms between sciatica (sciatic nerve pain) and piriformis syndrome
Symptoms that are similar between the two are:
- Lower back pain
- Spread of lower back pain to the buttocks and above the back of the thigh
- Exacerbation of pain and discomfort when sitting
Misdiagnosis can delay your recovery and waste your money