Questions to ask the patient

• Where is the pain? Is it in the back, the buttock, or down the leg?
• Does it go below the knee, to the foot, or to the toes? Which side?
• How did it start? Was it sudden after lifting or bending, or gradual?
• Have you had earlier episodes of back pain? (Close questioning often shows months or years of intermittent back pain before the leg pain began. Campbell's Operative Orthopaedics, p. 2351-2352)
• Is the leg pain worse than the back pain? (In a true disc herniation the leg pain is usually equal to or greater than the back pain. If back pain dominates and leg pain is minimal, be careful before blaming the disc. Campbell's, p. 2352)
• Is it sharp, shooting, burning or electric?

• Does it get worse with sitting, driving, bending forward, or lifting? (Disc pain usually worsens with sitting and driving. Campbell's, p. 2352)
• Does coughing, sneezing or straining make it worse? (Campbell's, p. 2352)
• Does rest help? Which position eases it? (Rest, especially the semi-Fowler position, eases it. Campbell's, p. 2352)
• Is the pain uniform, or does it change with posture and activity? A bizarre or constant pattern makes the diagnosis doubtful.

• Do you have numbness or tingling? In which area? (Disc paresthesias follow one dermatome. Campbell's, p. 2352)
• Is there any weakness, foot drop, tripping, or trouble standing on your toes or heels?
• Are both legs affected? (Generalized symptoms make a simple unilateral disc herniation less likely. Campbell's, p. 2352)

• Any difficulty passing urine, loss of control, or retention?
• Any change in bowel control, or constipation?
• Any numbness around the genitals, anus or inner thighs (saddle anaesthesia)?
• Any new sexual dysfunction?
• Do you have weakness or numbness in both legs? (Together with sphincter loss, this means cauda equina syndrome. Campbell's, p. 2352)

• Fever, weight loss, or night pain? These suggest infection or tumour.
• Any history of cancer, TB, or steroid use?
• Any significant trauma? Is there pain at rest that doesn't ease?
• How old are you? Is there osteoporosis?
• Are there morning stiffness and a pattern of improvement with activity? This suggests ankylosing spondylitis.
• Is the pain worse on walking and relieved by sitting or bending forward? This suggests spinal stenosis and neurogenic claudication, which is more common in older people.

• What is your occupation? Do you do heavy lifting, or sit or drive for long periods?
• How far can you walk? Can you sleep? Does it limit daily activities?
• What treatment have you tried (analgesics, physiotherapy, injections), and what was the response?
• Any diabetes (neuropathy can mimic this), smoking, or obesity?
• Any past spine surgery?

Examination to follow the history

• Inspection and palpation: look for loss of lumbar lordosis, a list or scoliosis, paraspinal spasm, and spinous process tenderness (Campbell's, p. 2352).
• Straight leg raising (SLR): pain below 40 degrees suggests a disc protruding onto a nerve root. Pain above 40 degrees suggests a nerve root that is abnormally sensitive from a cause not necessarily a disc (S Das, A Manual on Clinical Surgery, p. 299-300).
• Lasègue sign: at the angle where pain begins, dorsiflex the ankle passively. Pain that worsens confirms root irritation. A sacroiliac joint problem will not worsen with ankle dorsiflexion (S Das, p. 300).
• Crossed SLR: pain in the affected leg when the opposite leg is raised is regarded as pathognomonic of a herniated disc (Campbell's, p. 2353). Ipsilateral and contralateral SLR are the most important signs for lumbar disc herniation in sciatica (Goldman-Cecil Medicine).
• Femoral nerve stretch test: thigh pain suggests an upper lumbar (L2-3) disc (S Das, p. 300).
• Neurological examination: check power, sensation, reflexes, and perianal sensation and anal tone if you suspect cauda equina.

Next steps

• MRI of the lumbosacral spine is the main investigation. Order it urgently if you suspect cauda equina syndrome.
• Most patients improve with conservative care. Surgery is for those with intractable pain, progressive deficit, or cauda equina syndrome.