Low Back Pain

Pain localized to lumbosacral region: acute (<6 weeks), subacute (6-12 weeks), chronic (>12 weeks); non-specific mechanical (>90%), radicular, or specific serious pathology (rare but must not be missed).

• Mechanical: worse with movement, relieved by rest, no neurological deficit, no radiation below knee
• Radicular (sciatica): pain radiating below knee dermatomally, associated numbness/weakness, positive straight leg raise
• Cauda equina syndrome (SURGICAL EMERGENCY): bilateral leg pain/weakness, saddle anesthesia, urinary retention/incontinence, fecal incontinence/reduced anal tone, sexual dysfunction, emergency MRI + urgent decompression
• Fracture red flags: significant trauma, osteoporosis with minor trauma, prolonged corticosteroid use
• Malignancy red flags: age >50, cancer history, weight loss, night pain, failure to improve
• Infection red flags: fever, IV drug use, recent spinal procedure, immunosuppression, severe unremitting pain
• Inflammatory red flags: age <40, insidious onset, morning stiffness >30 min improving with exercise, alternating buttock pain

Non-specific mechanical without red flags: no routine imaging needed.

Red flags present: urgent MRI (cauda equina, same-day emergency; malignancy/infection, urgent); X-ray/CT/MRI if fracture suspected; bloods per suspected cause. Radicular symptoms persisting >6 weeks or progressive deficit: MRI if intervention considered.

Differentials: disc herniation, spinal stenosis, spondylolisthesis, fracture, malignancy, infection, inflammatory spondyloarthropathy, referred pain (renal, aortic, pancreatic, gynecological), myofascial pain, fibromyalgia.

Acute non-specific:

• Reassurance, education, encourage continued activity (bed rest NOT recommended)
• NSAIDs first-line, paracetamol adjunct; avoid routine opioids
• Muscle relaxants: short-term option for significant spasm

Subacute/chronic:

• Exercise therapy: core strengthening, general activity program
• Physiotherapy: manual therapy, exercise-based rehab
• CBT: for chronic pain with functional impact/fear-avoidance
• Duloxetine: option for chronic LBP
• Avoid long-term opioids

Radicular pain: conservative management initially (majority resolve within 6-12 weeks); epidural corticosteroid injection for refractory pain; surgical discectomy for persistent significant pain with correlating MRI findings or progressive deficit

Cauda equina: EMERGENCY, immediate MRI, urgent surgical decompression (ideally within 24-48h)

Spinal stenosis: flexion-relieving activity modification, physiotherapy, epidural injections, surgical decompression for refractory symptoms

Referral: emergency for cauda equina; urgent for suspected malignancy/infection/fracture; spine surgery for persistent radicular symptoms/progressive deficit; rheumatology for suspected inflammatory disease; pain management for chronic refractory disease.