What causes sciatica? 4 possible conditions
Your sciatic nerve begins at your spinal cord, goes through your hips and buttocks, and then branches down each leg. This nerve is the body’s longest nerve and one of the most important ones, as it has a direct effect on your ability to control and feel your legs. When this nerve is irritated, you will experience sciatica.
Sciatica is a sensation that can manifest itself as a moderate to excruciating pain that you feel in your back, buttocks, and legs. You may also feel weakness or numbness in these areas. Sciatica is a symptom caused by an underlying injury to the nerve or to an area that impacts the nerve, such as your vertebrae (the bones in the neck and back).
According to the American Academy of Orthopaedic Surgeons, sciatica is most likely to occur to those between 30 and 50 years old. (AAOS, 2007)
Sciatica can be caused by a number of conditions that involve the spine and that can affect the nerves running along your back. Other times, the cause is an injury, such as falling or spinal/sciatic nerve tumors.
Common conditions that can cause sciatica are described below.
Your vertebrae, or spinal bones, are separated by pieces of cartilage. Cartilage is filled with a thick, clear material to ensure flexibility and cushioning while you move around. Herniated disks occur when the first layer of the cartilage rips. The substance inside can extrude and compress the sciatic nerve, resulting in lower limb pain and numbness. It is estimated that one in every 50 people will experience a herniated disk in their lifetime, according to the American Academy of Orthopaedic Surgeons. (AAOS, 2007)
Also called lumbar spinal stenosis, this condition is characterized by the abnormal narrowing of the upper or lower spinal canal. This narrowing puts pressure on the spinal cord and the sciatic nerve roots.
This is one of the associated conditions of degenerative disk disorder. When one spinal bone (vertebra) extends forward over another, the extended spinal bone can pinch your sciatic nerve.
Piriformis syndrome is a rare neuromuscular disorder in which the piriformis muscle (the muscle that connects the lower portion of your spine to your thighbones) involuntarily contracts or tightens, causing sciatica. The sciatica occurs because of the pressure the tightening places on the sciatic nerve. Piriformis syndrome can worsen as the result of such commonplace events as sitting for long periods of time, falling, or being involved in a fender-bender.
Sciatica is a very distinct type of symptom. If you are experiencing pain that flows from your lower back through your buttock area and into your lower limbs, it is typically sciatica.
Sciatica is the result of damage or injury to the sciatic nerve, so other symptoms of nerve damage are usually present with the pain. Other symptoms of sciatica may include:
- pain that gets worse with movement
- numbness/weakness: This symptom can occur in your legs or feet and is usually felt along the sciatic nerve pathway. In severe cases, there can be a loss of feeling and/or movement.
- pins and needles: This is a painful tingling in your toes or feet.
- incontinence: This is the term for the inability to control your bladder or bowels. This is a rare symptom of cauda equina syndrome (which is explained ahead) and calls for immediate emergency attention.
When to Seek Medical Attention
Seek immediate medical attention in the case of the following symptoms:
- Your pain comes after a severe injury or accident.
- You have sudden, excruciating pain in your lower back or leg that is coupled with numbness or muscle weakness in that same leg.
- You are not able to control your bladder or bowels (symptom of cauda equina syndrome).
Cauda Equina Syndrome
This is a rare disorder that can cause paralysis, chronic bladder and bowel issues, and decreased sexual sensation if left untreated. Because this disorder often develops slowly, when symptoms appear, it is important to make an appointment with your doctor immediately.
Symptoms of this disorder include:
- inability to control your bladder or bowels (this includes retaining waste as well)
- pain, numbness, or weakness in one or both of your legs, making it hard to get up after sitting; you may notice yourself stumbling when trying to get up
- a noticeable progression or sudden severe loss of feeling in your lower body area, which includes the area between the legs, the buttocks, the inner thighs, the backs of the legs, and the heels and entire foot
Since sciatica is, itself, a symptom that can vary from condition to condition and person to person, your doctor will first want to get your full medical background. This includes whether or not you have had any recent injuries, where you feel the pain, and how the pain feels. The next step is a physical exam that will include testing your muscle strength and reflexes. Your doctor might also have you do some stretching and moving exercises to determine which ones bring about more pain.
The next round of diagnosis is for individuals who have dealt with sciatica for longer than a month or have a major illness such as cancer. Nerve tests will allow your doctor to examine the way nerve impulses are being conducted by the nerve and see if there are any abnormalities. Imaging tests will allow a doctor to get a look at your spine, which will help him or her to determine the sciatica’s cause. The most common imaging tests used to diagnose sciatica and to find its cause are:
- X-ray of spine: Normal X-rays will not be able to provide a view of sciatic nerve damage, but a spinal X-ray can reveal herniated disks and other nerve damage.
- magnetic resonance imaging (MRI): An MRI uses a magnet and radio waves to create detailed images of your back.
- computed tomography (CT) scan: A CT scan uses radiation to create detailed images of your body. Your doctor will more than likely inject a special dye into your spine (in a process called a CT myelogram) to help produce clearer pictures of your spinal cord and nerves. (Mayo Clinic, 2010)
Upon first diagnosis of sciatica, your doctor will often give you tips for treating your sciatica pain. One of the most important things to remember is to keep your daily activities going as much as possible, as lying in bed or avoiding activity can create a worse situation than you started with.
Some commonly suggested at-home treatments are described below.
You can purchase ice packs or even use a package of frozen vegetables. Wrap the ice pack or frozen vegetables in a towel and then apply to the affected area for 20 minutes a day, several times a day during the first few days of pain. This will help to reduce swelling and ease pain.
You can also purchase hot packs or a heating pad. It is recommended that you use ice the first couple of days. After two or three days, switch to heat. If you continue to have pain, try alternating between ice and heat therapy.
Gentle stretching of the lower back can also be helpful. A good way to do quality stretching is to get personal, one-on-one physical therapy or even yoga instruction from a physical therapist or instructor who is aware of and trained in dealing with your injury.
Over-the-counter medications, such as aspirin and ibuprofen, can also help with pain, inflammation and swelling. Be careful using aspirin excessively due to its potential complications, which include stomach bleeding and ulcers.
The more you stay active, the more endorphins your body releases. Endorphins are painkillers made by the body. Keep to low-impact activities at first, such as swimming and stationary bicycling. As your pain decreases and your endurance improves, create an exercise regimen that includes aerobics, core stability, and strength training. A regimen with these components can decrease the risk of future back problems. (Mayo, 2010)
If at-home treatments fail to treat your pain effectively, the doctor might suggest that you take further measures, including:
- physical therapy: Exercises will help to improve posture and strengthen back muscles.
- prescription medication: Doctors might prescribe muscle relaxers, narcotic pain relief, and even antidepressants. Antidepressants can increase your body’s endorphin production.
- epidural steroid injections: Corticosteroid medications are injected into an area called the epidural space. The epidural space is the fluid that surrounds your spinal cord. Because of side effects, these injections are given on a limited basis.
- surgery: Surgery may be needed for severe pain or situations in which you have lost control of your bowel and bladder. The two most common types of surgery are diskectomy and microdiskectomy. Diskectomy is the removal of the part of the disk that is pressing on the sciatic nerve. Microdiskectomy is disk removal done through a small cut while the doctor utilizes a microscope.
Certain behaviors or factors can make sciatica more likely. The most common factors for developing sciatica include:
- age: As your body ages, it becomes more likely that parts will wear out or break down.
- occupation: Certain careers place a lot of strain on your back, especially those that involve lifting heavy objects, sitting for extended periods, or twisting movement.
- diabetes: This condition can increase the risk of nerve damage.
- smoking: Smoking can cause the outer layer of your spinal disks to break down.
The world of alternative medicine is growing in popularity. There are a number of alternative remedies for sciatica. These include:
- acupuncture: Sterilized needles are inserted at key points to affect the flow of energy within your body. This procedure is virtually painless.
- chiropractic care: A chiropractor will manipulate your spine to achieve maximum spinal mobility.
- hypnosis: A trained professional will induce hypnosis. Hypnosis is intended to put a patient in a very relaxed, focused state of mind, which will allow him or her to best receive healthy suggestions and instructions. In the case of sciatic pain, the messages might involve pain relief.
The following steps can assist you in preventing sciatica or from keeping it from reoccurring:
- Exercise often. Strengthening your back muscles and your stomach or core muscles is the key to maintaining a healthy back.
- Mind your posture. Make sure your chairs offer proper support for your back. You should be able to place your feet on the floor, and make sure to use your armrests.
- Mind how you move. Take care of yourself. Lift heavy objects the proper way by bending at the knees and keeping your back straight.
- Baker, R. M. (2009, July 17). Epidural Steroid Injections. KnowYourBack.org. Retrieved July 22, 2012, from http://www.knowyourback.org/Pages/Treatments/InjectionTreatments/ES_Injections.aspx
- Cauda Equina Syndrome. (2007, October). American Academy of Orthopaedic Surgeons. Retrieved July 22, 2012, from http://orthoinfo.aaos.org/topic.cfm?topic=a00362 http://orthoinfo.aaos.org/topic.cfm?topic=a00362
- NINDS Piriformis Syndrome Information Page. National Institute of Neurological Disorders and Stroke.Retrieved July 21, 2012, from http://www.ninds.nih.gov/disorders/piriformis_syndrome/piriformis_syndrome.htm
- Sciatica. (2010, April 22). Mayo Clinic. Retrieved July 5, 2012, from http://www.mayoclinic.com/health/sciatica/DS00516/DSECTION=causes
- Sciatica. (2007, October). American Academy of Orthopaedic Surgeons.Retrieved July 7, 2012, from http://orthoinfo.aaos.org/topic.cfm?topic=a00351 http://orthoinfo.aaos.org/topic.cfm?topic=a00351
- Spinal Stenosis. (2012, June 28). Mayo Clinic.Retrieved July 21, 2012, from http://www.mayoclinic.com/health/spinal-stenosis/DS00515/
- What is Sciatica? (2010, March 8). Cleveland Clinic.Retrieved July 7, 2012, from http://my.clevelandclinic.org/disorders/sciatica/hic_what_is_sciatica.aspx
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