Sciatica is a very common condition, especially in men and women between the ages of 30 and 50.
The pain usually starts in the lower back or hips and then radiates into the back of the thighs and can spread down into the legs with the possibility of affecting the feet. This is the path of the sciatic nerve and it’s branches – it is the longest nerve in your body and runs from your spinal cord to your buttock and hip area and down the back of each leg.
Sciatica is a symptom (what you feel), not a disorder (the cause of the problem).
The radiating pain of sciatica signals another problem involving the compression or irritation of nerves as they exit the spinal canal (space which the spinal cord travels).
Hence, you will sometimes hear terms such as nerve root pain or radiculopathy instead.
References
Konstantinou K, Dunn KM. Sciatica: review of epidemiological studies and prevalence estimates. Spine. 2008;33:2464–2472.
Symptoms
Sciatica may feel like a bad leg cramp that lasts for weeks before it goes away. It may be come on suddenly and can persist for days or weeks.
You may experience the following:
- Pain in your lower back or hip that radiates down from your buttock to the back of one thigh and into your leg.
- especially when you sit, sneeze or cough.
- Weakness,
- Down your leg. Pins and needles, numbness, or a burning or tingling sensation down your leg.
- Loss of bladder or bowel control – sign of cauda equina syndrome, a rare but serious condition that requires emergency care. If you experience either of these symptoms, seek medical help immediately.
References
Chou R, Qaseem A, Snow V, et al; Clinical Efficacy Assessment Subcommittee of the American College of Physicians; American College of Physicians; American Pain Society Low Back Pain Guidelines Panel. Diagnosis and treatment of low back pain: a joint clinical practice guideline from the American College of Physicians and the American Pain Society. Ann Intern Med. 2007;147(7):478-491.
Causes
Herniated Disc
This is the most common cause of sciatica. The gel-like disc between the block bones (vertebrae) of the spine bulge outward hitting the nerves of the spine producing the symptoms of sciatica.
Degenerative Arthritis
Due to wear and tear of the bones of the spine. This can lead to narrowing of the spinal canal (spinal stenosis) or stress fractures or instability of spinal joints (spondylolysis and spondylolisthesis).
Spinal Tumours
Rarely, tumours will compress the nerve roots or spinal cord causing compressing symptoms such as sciatica. Tumours can occur in the spinal cord, between the covering layers of the spinal cord (meninges) or in the spaces between the spinal cord and the spinal bones (vertebrae).
Infection and inflammation
Both cause tissue swelling around the nerve roots, hence may increase pressure around the affected areas.
Trauma (single or cumulative small trauma)
A fall or blow to the spine or buttock can affect the nerves of the lower back producing symptoms of sciatica.
Piriformis Syndrome
This is generally due to shortening or spasm of the piriformis muscle (a muscle in the buttock) from trauma or overuse, compressing the nerve beneath it to cause sciatica.
Pelvic Instability
Uterine pressure during pregnancy
Vascular Problems
Abnormal blood vessels in and around the spinal canal.
References
Stafford MA, Peng P, Hill DA. Sciatica: a review of history, epidemiology, pathogenesis, and the role of epidural steroid injection in management. Br J Anaesth. 2007;99(4):461-473.
Risk Factors
Factors predisposing to sciatica include:
- History of low back trauma
- Heavy smoking
- Pregnancy
- Tall skeletal frame
- Occupational loading of the low back
- Back strain from unaccustomed physical exertion
Factors in 14-year-old adolescents that predicted sciatica in adulthood:
- Smoking
- Obesity (i.e., body mass index (BMI) > 95th percentile for age)
- Sports participation
References
Rivinoja AE, Paananen MV, Taimela SP, et al. Sports, Smoking, and Overweight During Adolescence as Predictors of Sciatica in Adulthood: A 28-Year Follow-up Study of a Birth Cohort. American Journal of Epidemiology. 173(8):890-897.
Investigations
Sciatica is mainly diagnosed by history taking and physical examination.
Your doctor may ask you some of the following questions:
- What are your symptoms? When are they worse?
- When and how did your symptoms start?
- What has changed since?
- Has there been any bowel or bladder changes?
- What makes the symptoms better or worse?
- What investigations have been done by doctors in the past to evaluate the cause of your symptoms?
- Have you had treatment for your symptoms, such as medications, steriod injections and surgery? Were they effective?
- Have you tried any other alternative therapy for your problems?
- Do you have any other medical problems?
Your doctor may also want to test the following:
- Your gait – by asking you to walk
- Power of your legs
- Range of motion of your back and leg joints
- Reflexes
- Sensation
- Straight Leg Test – this may reproduce your symptoms. Your doctor will ask you to keep your knee straight while bending your hip. He or she may also bend your ankle. Let your doctor know if you feel pain or numbness.
To further investigate the cause of your sciatica, your doctor may suggest a few tests including:
- X-ray. To detect evidence of spondylolisthesis (misalignment of the vertebrae), narrowed disks, or evidence of erosion that may suggest a tumour affecting the spine.
- CT scan. Allows visualization of the spinal cord and nerves.
- MRI scan. Allow visualization of the vertebral disks, ligaments, and muscles, as well as the presence of tumors.
References
Jensen TS, Albert HB, Soerensen JS, Manniche C, Leboeuf-Yde C. Natural course of disc morphology in patients with sciatica: an MRI study using a standardized qualitative classification system. Spine (Phila Pa 1976). 2006;31(14):1605-1613.
Complications
If you experience any of the following symptoms, it is essential you present to your nearest emergency department immediately.
- Difficulty passing urine
- Loss of sensation around anus region
- Extreme pain/numbness/weakness in both legs
These are symptoms of cauda equina syndrome.
It is also important to let your doctor know if you are experiencing fever, increased night pain & night sweats, as they may indicate a more sinister cause for the sciatica.
Your mental health
The pain from sciatica may prevent you from leading a normal life and this can be frustrating. If you find yourself having low moods most times of the week and no longer enjoying activities you use to enjoy, it is important to talk with friends or family. Your doctor will be available if you need help.
References
Stafford MA, Peng P, Hill DA. Sciatica: a review of history, epidemiology, pathogenesis, and the role of epidural steroid injection in management. Br J Anaesth. 2007;99(4):461-473.
Treatment
You are encouraged to return to your normal daily activities as soon as possible. Bed rest has not been found to improve the symptoms of sciatica and instead may worsen the pain. There are also physical exercises you can do to improve your strength and range of movements.
Acupuncture, spinal manipulation and corsets have not shown to make a significant difference in the improvement of sciatica symptoms. These alternative treatments are often tried by patients but are not usually recommended by doctors.
Non-surgical Treatments
It is reasonable that your doctor will put you on a trial of painkillers. The type of painkillers (paracetamol, NSAIDs, opioids etc.) will depend on the severity of your pain and he or she may change the strength of painkillers as your symptoms change. You may also be prescribed muscle relaxants to reduce spasm of muscle around the nerve. This has shown to work for some people. It is important to discuss the side effects of these medications, if any, with your doctor.
If the pain does not improve with oral medications, the next step to treatment is to try epidural corticosteroid injections. This involves the injection of steroids into the space within the spinal cord that surrounds the nerves using a needle, around the lower back. Studies have shown positive short-term effects for reducing pain in a proportion of people. Unfortunately, the pain will eventually return for these people hence long-terms effects should not be expected.
Surgical Treatments
- Laminectomy
- Discectomy
- Spinal Fusion
References
Valat JP, Genevay S, Marty M, Rozenberg S, Koes B. Sciatica. Best Pract Res Clin Rheumatol 2010;24(2):241-252.
Jacobs WCH, Maurites VT, Arts M, et al. Surgery versus conservative management of sciatica due to a lumbar herniated disc: a systematic review. Eur Spine J (2011) 20:513–522
Seeking Advice
Your Family Doctor (GP)
Your Family Doctor will be able to diagnose and help treat your problem. He or she will be able to
- tell you about your problem
- advise you of the best treatment methods
- prescribe you medications
- and if necessary, refer you to Specialists (Consultants) for further treatment
Prevention
- Try to take rests in between activities that strain your back.
- Maintain postural awareness during daily activities.
- Reduce your risk factors such as obesity and smoking.