Sciatica

Definition

Sciatica is a condition characterised by pain that radiates along the path of the sciatic nerve, which branches from the lower back through the hips and buttocks and down each leg. Typically, sciatica affects only one side of the body.

Aetiology

Sciatica can be caused by various factors, including:

Herniated disc: The most common cause, where a disc in the spine presses on a nerve
Spinal stenosis: Narrowing of the spinal canal
Spondylolisthesis: A condition where one vertebra slips over another
Trauma: Injury to the lower back or spine
Tumours: Rare, but can compress the sciatic nerve
Infections: Affecting the spine or nearby areas

Pathophysiology

The pain associated with sciatica occurs when the sciatic nerve is compressed or irritated. This can result from disc herniation, spinal stenosis, or other conditions that cause inflammation or mechanical pressure on the nerve roots that form the sciatic nerve.

Risk Factors

Age: Age-related changes in the spine, such as herniated discs and bone spurs, are the most common causes of sciatica
Occupation: Jobs that require heavy lifting, twisting the back, or driving for long periods
Prolonged sitting: People who sit for prolonged periods or have a sedentary lifestyle
Diabetes: This condition increases the risk of nerve damage

Signs and Symptoms

Pain radiating from the lower back to the buttock and down the back of the leg
Sharp, burning, or shooting pain
Numbness or weakness in the leg or foot
Tingling or pins-and-needles sensation
Pain that worsens with movement, such as coughing or sneezing

Red Flags

Severe, progressive lower limb weakness
Loss of bowel or bladder function
Severe, unremitting pain that is not relieved by standard measures
Unexplained weight loss or history of cancer
Recent significant trauma

Investigations

Clinical history and physical examination
Imaging studies (e.g., MRI or CT scan) if symptoms are severe or do not improve with conservative treatment
Electromyography (EMG) to assess nerve function
X-rays to check for fractures or bone abnormalities

Management

Primary Care Management

Initial assessment and diagnosis based on clinical history and physical examination
Pain management with analgesics (e.g., NSAIDs, Paracetamol)
Physical therapy and exercise to improve flexibility and strengthen the back muscles
Education on proper body mechanics and posture
Referral to a specialist if symptoms persist or worsen

Specialist Management

Advanced diagnostic testing (e.g., MRI, EMG)
Prescription of stronger pain medications if necessary (e.g., muscle relaxants, opioids)
Epidural steroid injections to reduce inflammation and pain
Surgical intervention in severe cases (e.g., microdiscectomy, laminectomy)
Multidisciplinary approach including pain management specialists, physical therapists, and neurologists

Example Management for Sciatica

A patient presenting with mild to moderate sciatica may be initially managed with NSAIDs, such as ibuprofen, and a short course of physical therapy to strengthen the back and improve posture. The patient should be educated on proper body mechanics to avoid exacerbating the condition. If the pain persists or worsens, referral to a specialist for further evaluation, MRI imaging, and potential epidural steroid injections may be necessary. Surgery may be considered if conservative treatments fail and the patient's quality of life is significantly affected.

References

NICE. (2024). Low Back Pain and Sciatica in Over 16s: Assessment and Management. Retrieved from NICE
NHS. (2023). Sciatica. Retrieved from NHS
Ropper, A. H., & Samuels, M. A. (2019). Adams and Victor's Principles of Neurology. 11th ed. McGraw-Hill Education.
Watters, W. C., et al. (2009). Guideline on the Treatment of Lumbar Disc Herniation with Radiculopathy. The Spine Journal.
Frymoyer, J. W., & Cats-Baril, W. L. (1991). An Overview of the Incidence and Costs of Low Back Pain. Orthopedic Clinics of North America.