Sciatic Pain
The Sciatic nerve is the largest and thickest nerve in the body. It runs from either side of the lower back, runs through the buttock and knee where it divides into two branches. Sciatic pain commonly referred as sciatica is the nerve pain that radiates from the lower back through buttock and hip and sometimes down the foot. This is the pathway of sciatic nerve along which pain radiates. Pain commonly occurs when sciatic nerve is pinched, entrapped or compressed somewhere along its pathway. This pinching can occur due to many underlying causes.
Table of Contents
Causes of Sciatica
Pain can occur due to many reasons including:
Disc herniation is a fragment of slipped or bulged disc puts an extra pressure on the nerves that pass through the space between two vertebrae. This increased pressure pinches the nerve and results in pain. Herniation mostly occurs at L4-L5 and L5-S1 level.
Spinal stenosis is the narrowing of space between vertebrae. This narrowing of space pinches the nerve between vertebrae and decreases the nerve supply. Stenosis mostly occurs in older people.
Disc dislocation Weakness or injury may result in dislocation of the disc that results in putting pressure on the nerve resulting in pain and numbness in the leg.
Tumor Tumors or growths that may be benign or cancerous may cause local compression of the nerve that cause sciatica
Underlying disease Some diseases like diabetes can cause sciatic pain but it is not true sciatica. Diabetic neuropathy causes pain and numbness in hands, feet and legs. Symptoms may look like sciatica.
Spondylolisthesis is the slipping of upper vertebrae over the lower one. This slippage presses the nerve between two vertebrae and results in symptoms of sciatica.
Ankylosing spondylitis Chronic inflammation in the spine may reduce the space between vertebrae and cause nerve compression.
Piriformis syndrome The Piriformis is a muscle that is located in the buttock region. Due to some injury or any other cause this muscle undergoes spasm and compresses the nearby sciatic nerve. This compression results in numbness and tingling sensations in the leg and foot. Pain is non discogenic in nature.
Osteoarthritis is the inflammation of bones and joints. This degenerative disease of vertebral bones and joints reduces flexibility of the joints, may result in osteophyte formation that irritates or pinches the nerve causing sciatica like symptoms along the nerve pathway.
Types of Sciatica
True Sciatica is when sciatic nerve or its branch is entrapped due to disc herniation, spondylosis or spinal stenosis. True sciatica can also be referred as discogenic sciatica.
False Sciatica occurs when sciatic nerve is compressed when muscles of the buttocks or lower leg undergo spasm. As this compression is not due to discal or vertebral involvement, this often is known as false or non-discogenic sciatica.
Radicular sciatica occurs when pain radiates from lower back through buttocks and down to the foot. It may be of mechanical or so-called inflammatory origin. Mechanical sciatica results when an abnormal pressure is put on the spine whether it is due to poor posture, poor seating, or weight lifting. This pressure in turn compresses the nerve that radiates down to its pathway. Due to herniated disc, spinal stenosis, or bone spurs sciatic nerve gets inflamed. This inflammation of nerve causes pain and numbness along the nerve pathway.
Truncal Sciatica as described in piriformis muscle syndrome is an entrapment of sciatic nerve by piriformis muscle. Pain starts in the trunk and buttocks initially, therefore, known as truncal sciatica.
Peripheral Sciatica is when the popliteal nerve (a branch of sciatic nerve) gets entrapped around the neck of fibula, pain and numbness are experienced in the lower leg and foot (periphery).
Symptoms
- Symptoms of sciatic pain may be unilateral, or bilateral depending on the site of nerve compression.
- You may experience pain in leg including buttock, calf and foot. Pain may be sharp, shooting or stabbing in nature. Some injury or weakness may
- Muscle weakness may be experienced due to lack of nerve supply.
- Tingling sensation may be felt in leg, toes and foot.
- Numbness in leg is also a remarkable symptom.
- Pain occurs when you sit or stand for hours.
- Pain worsens with bending of lumbar spine. Sudden movements during coughing or sneezing may exaggerate symptoms.
- A disturbance in normal gait may be experienced.
- Some reflexes like ankle jerk reflex may also be diminished.
- Bowel and bladder control may also be lost in some severe cases.
Risk Factors
Mental stress puts a pressure on muscles and muscles become taut. This may be the reason of sciatic pain. Also, as oxygen supply to the brain increases during stress situation, it deprives other nerves of oxygen supply resulting in numbness and pain along the nerve root. During stress situation cytokines are also released that cause inflammation of the nerve resulting in inflammatory sciatica.
Physical overload exerts pressure on the spine. While lifting a heavy object spine extends and puts pressure on the nerve that result in the symptoms of sciatic pain.
Obesity exerts a stress over spine and can trigger sciatica.
Tumor or any mass either benign or malignant may result in nerve compression causing sciatic pain.
Arthritis Joint inflammation in the vertebral column can cause inflammation of the sciatic nerve and cause sciatica.
Core stability Core muscles are the muscles of back and abdomen. If they are weak an extra pressure is put up on the lumbar vertebrae. This compresses the nerve causing pain and numbness in the leg.
Posture Poor postural habits i.e, lordotic posture cause extension of lumbar spine. This approximation of vertebrae compresses the nerve and cause sciatic pain.
Diabetes does not cause true sciatica. It can cause diabetic neuropathy causing symptoms like that of sciatic pain.
Sedentary lifestyle or jobs that require prolonged standing, sitting and driving can cause compression of the nerve. It results in sciatic pain.
Smoking causes wearing of the spinal disc resulting in lumbar radiculopathy.
Pregnancy Lumbar lordosis causes nerve compression and cause sciatica.
Prevention
Proper body mechanics and good posture while sitting, standing, sleeping, lifting some weight or during any physical activity can reduce the pressure on spine and risk of nerve compression is also reduced.
Regular exercise is essential for general body muscles strengthening. Core muscles strengthening need special attention in this regard. These muscles are responsible for good body posture and mechanics.
Stop smoking because nicotine reduces blood supply to the bones that causes wearing of bones. Spine becomes weak and extra pressure on the nerve results in its compression.
Weight management Maintaining a healthy body weight reduces the stress on spine and chances of nerve entrapment are minimized.
Physical job If you are involved in jobs that require prolonged standing or sitting, then, try to change your position after every half an hour to one hour. It reduces the risk of nerve compression or entrapment that ultimately reduces the risk of sciatic pain.
Mental stress is not good for general body health. Just start working on relieving your stress if you don’t want to be a patient ultimately.
Treatment
Sciatic pain can be relieved by using medications, surgery and also by physical therapy treatment.
Medical treatment Prescription depends on the origin of pain. Aspirin for quick pain relief and NSAIDs (Non-steroidal anti-inflammatory drugs) as pain killers and anti-inflammatory drugs can be used. If cause of pain is due to muscle spasm then muscle relaxants are prescribed. And if back pain is due to stress then anti-depressants are given. However, if disc is herniated or ruptured steroid injections are given in the intervertebral space.
Surgical treatment generally comprises two procedures. It may be discectomy and laminectomy. When nerve is entrapped due to herniated, bulged, or slipped disc ultimate treatment is the removal of a small part of disc by surgery (discectomy). Decompression can also be performed that increases the intervertebral space that is narrowed either due to disc herniation or spinal stenosis. In patients with spinal stenosis in lumbar area, a part or full lamina is removed (laminectomy).
Physical therapy treatment includes the following procedures:
Cold pack Cold therapy is very beneficial if the condition is acute. By icing or applying cold back on lower back will numb the pain in its origin. It also reduces inflammation of the nerve and muscle spasm.
Heat therapy applied on the lower back and buttock region increases the blood supply to muscles. It removes the waste substances and help relieving the pain. Alternate cold and heat therapy reduce the symptoms more quickly.
Muscle strengthening of back, abdomen and buttocks reduces the symptoms. Increased muscle strength reduces the risk of pressure on vertebrae and pain is relieved. Plank or bridge hold is highly beneficial in this respect that strengthen the core muscles and muscles of leg.
Stretching the muscles of buttocks (hamstrings), lower back and calf reduce the muscle spasm and sciatic pain is relieved if it is due to muscular spasm. Also stretching a muscle improves its blood supply and the symptoms of pain are subsided.
Flexion and extension of spine It depends on the origin of pain if he is flexion bias (pain relieved on flexing the spine) or extension bias (symptoms reduced on extension of spine). After evaluation flexion or extension of spine is performed (according to patient’s preference). Movement of spine reduces the nerve entrapment and compression thus relieving the pain.
Nerve mobilization is performed by a trained therapist. Nerve is stretched along its pathway that releases the entrapped nerve and pain subsides.
Joint mobilization of lumbar vertebrae puts a pressure on the joints sue to which disc bulge is reduced. It reduces the compression force over the nerve and pain is relieved.
Joint manipulation is a sudden, quick forceful thrust applied by the therapist that reduces the pain and other symptoms of sciatic pain. It also also restores the normal range of muscles.
Dry needling is a technique in which trigger points in muscles are released using a small needle. As the nerve passes through muscles it gets entrapped due to trigger points or spasm. Using dry needling technique nerve is released that has undergone entrapment. Hence the pain and numbness go away.
Soft tissue mobilization is another technique to reduce muscle spasm and nerve entrapment. Therapist may perform this mobilization with the help of some instrument or may use his hands.
Functional training restores the strength of patient. Patient performs active exercise while therapist helps him in the painful range so that the muscle strength is gained.