Sciatica is a common physical condition, affecting approximately 1.6 percent of the overall population, with a notably higher incidence of around 43 percent among specific occupational groups [1]. This condition primarily manifests as intense pain originating from the sciatic nerve, extending from the lower back, through the buttocks, and down the legs, ultimately reaching below the knee. The sciatic nerve serves a crucial role in connecting the spinal cord to the leg and foot muscles. Sciatica-induced pain can be excruciating and debilitating. It can disrupt daily activities and significantly affect the quality of life for those afflicted.
In addition to the characteristic pain, sciatica can also manifest as numbness or tingling sensations. The sciatic nerve sensory area extends from the thigh to half of the area below the knee. The diverse symptoms highlight the complexity of sciatica, affecting individuals beyond just pain. It not only impacts physical health but also has profound mental and emotional implications. Persistent discomfort and limited mobility can diminish overall well-being.
Symptoms of Sciatic Nerve Compression
If you’re wondering whether you have sciatica, check for the following symptoms:
| Symptom | Description |
|---|---|
| Severe Leg Pain | Intense pain in one leg, stronger than the pain in the lower back |
| Posterior Leg Radiating Pain | Pain typically spreads from the back of the leg below the knee |
| Numbness and Tingling in Leg | Feelings of numbness or tingling in the lower leg |
| Mechanical Compression/Irritation | Pressure or irritation on the nerves, tested by provoking pain in the affected leg |
To check for mechanical compression/ irritation of the sciatic nerve, your physician may conduct the following physical tests:
| Physical Test | Purpose | Procedure |
|---|---|---|
| Straight Leg Raise Test | To assess mechanical compression or irritation of nerve roots, especially the sciatic nerve. | The patient lies supine, and one leg is raised while keeping the knee straight. A positive test is indicated if the patient experiences pain along the sciatic nerve pathway. |
| Femoral Nerve Test | To evaluate the femoral nerve for compression or irritation. | The patient lies prone, and the therapist stabilizes the pelvis. The affected leg is flexed at the knee to its end range. Pain or discomfort during this maneuver may suggest femoral nerve involvement. |
| Slump Test | To provoke pain and assess neural tension in the spinal cord and peripheral nerves. | The patient is seated with hands behind their back for a neutral spine. They slump forward at the thoracic and lumbar spine. If no pain is felt, various neck and knee movements are performed to reproduce or alleviate symptoms. A positive test indicates pain reproduction. |
| Neurological Deficit Signs | – Muscle Weakness: Reduction in muscle strength associated with the affected nerve root. – Absence of Tendon Reflexes: Diminished or absent reflexes indicating nerve dysfunction. – Sensory Deficit: Altered or loss of sensation in the dermatomal distribution. | These signs are indicative of nerve dysfunction and can be assessed through clinical examination, including strength testing, reflex assessment, and sensory examination. |
Causes of Sciatic Nerve Compression
Sciatica has two main types: intraspinal and extraspinal, indicating if symptoms come from inside or outside the spine. Intraspinal sciatica, which is within the spine, has different causes, with radiculopathy, often called a “pinched nerve,” being a significant factor. Radiculopathy involves conditions where nerves are affected, causing impaired functioning.
Moreover, intraspinal sciatica can be caused by lumbar disc herniation, which involves a disc bulging, protruding, or rupturing in the lower back. Stenosis, the narrowing of the spinal canal in the lower back, is another contributor. Together, these factors compress or irritate the sciatic nerve, leading to sciatic symptoms.
On the other hand, extraspinal sciatica stems from causes outside the spinal column. One notable factor is piriformis, a condition in which the piriformis muscle located in the buttocks compresses the sciatic nerve. This compression leads to the onset of sciatic symptoms, adding a layer of complexity to the diagnosis and management of sciatica.
Sacroiliitis, impacting the sacroiliac joints, and hamstring injury are external factors that can cause sciatica. The varied causes highlight the complex nature of sciatica. Hence, a thorough understanding of both intraspinal and extraspinal factors is crucial for precise diagnosis and successful treatment.
Intraspinal Causes
| Intraspinal Causes | Description | Key Characteristics |
|---|---|---|
| Disc Herniation | Commonly occurs due to aging, where the cushion-like discs in the back may bulge, protrude, or rupture. | Bulging, protruding, or ruptured disk in the lower back. Can cause irritation or compression of the sciatic nerve, leading to sciatic symptoms. |
| Trauma | Rarely, sciatica can result from a spine injury, such as a fall or accident. | Injury-related damage to the spine can cause sciatic symptoms. |
| Foraminal Stenosis | This happens when the openings (foramina) in the spine narrow, often due to wear and tear. | Narrowing of the spaces where nerves exit the spine, contributing to sciatic symptoms. |
| Soft Tissue Stenosis | Caused by non-bony structures like cysts or tumors, narrowing the spinal canal. | Narrowing of the spinal canal due to non-bony structures, leading to compression or irritation of the sciatic nerve. |
| Lumbosacral Plexus | Conditions outside the spine, like tumors, trauma, or infections, can mimic sciatica. | Various conditions affecting the nerves outside the spine can mimic sciatic symptoms. |
| Muscle Entrapment | Piriformis Syndrome – Compression of the sciatic nerve by a muscle in the buttocks. | Compression of the sciatic nerve by the buttock muscle (piriformis), leading to sciatic symptoms. |
| Modifiable Risk Factors | Certain lifestyle factors like smoking, obesity, and heavy manual labor may increase the risk of experiencing sciatica. | Identified lifestyle factors that can contribute to the first episode of sciatica. |
Extraspinal Causes
| Extraspinal Causes | Description | Key Characteristics |
|---|---|---|
| Piriformis Syndrome | Compression of the sciatic nerve by a muscle in the buttocks. | Sciatic symptoms due to compression by the buttock muscle (piriformis), adding complexity to diagnosis and management. |
| Sacroilitis | Inflammation affecting the joints connecting the spine to the pelvis. | Sciatic symptoms associated with inflammation and dysfunction of the pelvis joints. |
| Hamstring Injury | Injury to the muscles in the back of the thigh leading to sciatic symptoms. | Sciatic symptoms induced by injury to the muscles in the back of the thigh. |
By recognizing and differentiating between these categories, healthcare professionals can tailor interventions to address the specific underlying causes, offering more targeted and personalised approaches to alleviate sciatic symptoms.
How is sciatica diagnosed?
Patient medical history and physical (neural tension) tests are some of the best means of diagnosing Scaitica. However, imaging tests such as the MRI may be used in exceptional circumstances. MRI is only recommended if the patient experiences loss of sensation and reflexes, and muscle weakness, has a history of trauma (injury), or has not been relieved of their symptoms for a prolonged period despite conservative care. If you believe your condition aligns with these criteria, you can discuss the possibility of an MRI with your doctor.
What is the prognosis for sciatica?
Most people experience an improvement in symptoms over time with either conservative treatment or surgery. In a five year follow-up of a Dutch randomised controlled trial (231 patients), only 8% of patients showed no recovery and 23% reported ongoing symptoms that fluctuated over time. About 55% of patients with sciatica reported improvement in pain and disability at one year in a recent UK primary care cohort study (452 patients) [2]. Although symptoms can be distressing and affect quality of life and daily productivity, they diminish over time with proper care and attention. Most people are able to live a comfortable life despite their condition through a whole host of recently developed remedies.
What are the treatment options available for Sciatica?
Sciatica care can be broadly categorised into conservative and surgical. When a patient is initially diagnosed with sciatica, treatment is aimed at alleviating pain and maintaining function while the compression and/or inflammation or the sciatic nerve root subsides. Patients are advised to remain active and avoid bed rest, so that their everyday activities continue unabated. They are also advised to remain on the lookout for and report any changes in the symptoms, particularly intensification of pain or loss of sensation and reflexes.
Exercise and Manual Therapy
Patients are encouraged to engage in physical activity, as it likely to reduce the intensity of leg and low back pain. However, according to a meta-analysis of research on the subject, it must be noted that patients with sciatica experience little to no difference by engaging in either bedrest or exercise. It is best to consult a physiotherapist or chiropractor when deciding how to exercise for sciatica patients. Acupuncture is not recommended in patients with sciatica.
Spinal Injections
An epidural injection is a medical procedure that involves injecting a medication into the space around your spinal nerves known as the epidural space. The injection helps decrease pain and swelling around the nerve root. With these injections, cortisone or another corticosteroid is placed into the tissue directly around where the pinched nerve meets the spine in an area known as the epidural space. As an anti-inflammatory, the corticosteroid relieves inflammation around the nerve. This can reduce pain in the back and the radiating pain related to sciatica, which might be felt in your legs or other areas.
Steroids, including corticosteroids, are very powerful. They should be used at the lowest strength possible while still being effective. There are different types of corticosteroids that can be used to treat sciatica, and each has different guidelines for how much medication should be used. Epidurals are only considered in cases of severe sciatica as a means of last resort before surgery.
When to consider surgery for sciatica?
People with persistent pain for more than 12 weeks from the onset of symptoms despite conservative treatment may be considered for surgery. After Imaging has confirmed lumbar disc herniation at the nerve root level corresponding with findings on clinical examination, a surgical procedure for removal of disc herniation is the commonest procedure. Studies suggest that surgery provides faster relief than conservative care in sciatica patients.
Living With Sciatica
Even though it may appear bleak right now, an entirely normal life is possible while living with Sciatica. For the majority of patients, conservative treatments such as heat and ice therapy can bring much reprieve. With medication and the right dietary and exercise regimen, pain can be relieved without much hassle. Even if the symptoms are dire, new and evolving interventions can help reduce the pain and alleviate the symptoms in very little time.
