Back Pain — Causes, Red Flags & Treatment — Causes, Diagnosis & When to See a Doctor | MyMedicPlus

Back pain is one of the most common medical complaints in the world and the leading single cause of disability globally, responsible for more years lived with disability than any other condition. It encompasses pain arising from the muscles, ligaments, intervertebral discs, facet joints, spinal nerves, or vertebrae of the cervical, thoracic, or lumbar spine — though the lumbar region (lower back) is by far the most frequently affected. Back pain ranges from a dull, persistent ache that limits daily activities to sharp, stabbing, or radiating pain that may extend down one or both legs (sciatica). It is classified by duration: acute (fewer than 6 weeks), subacute (6–12 weeks), or chronic (more than 12 weeks). The majority of acute episodes — approximately 90% — improve substantially within 4–6 weeks with conservative management. Chronic back pain, however, follows a more variable course and often requires a multidisciplinary approach involving physiotherapy, psychological support, and in selected cases, interventional or surgical treatment.

Muscle or ligament strain from sudden heavy lifting, awkward movements, or sustained poor posture is the most common cause of acute back pain. Herniated (prolapsed) intervertebral disc occurs when the disc's soft nucleus pushes through the outer fibrous ring, potentially compressing adjacent nerve roots and causing radiating leg pain (sciatica). Degenerative disc disease involves progressive loss of disc height and hydration with ageing, leading to stiffness and chronic pain. Spinal stenosis — narrowing of the spinal canal — causes neurogenic claudication, where pain, heaviness, or weakness in the legs appears with walking and is relieved by sitting forward. Facet joint osteoarthritis causes localised back pain that worsens on extension (leaning backward). Spondylolisthesis (forward slipping of one vertebra on another) can cause both back pain and neurological symptoms. Less common but serious causes include vertebral fractures from osteoporosis — especially in postmenopausal women and older men — kidney infection (pyelonephritis), malignancy (primary or metastatic spinal tumours), spinal infection (discitis, epidural abscess), and ankylosing spondylitis (inflammatory back pain in younger adults, characterised by morning stiffness improving with movement).

Certain features of back pain constitute medical red flags and demand urgent, same-day evaluation without delay. Bladder or bowel dysfunction (urinary retention, incontinence, or loss of control over bowel function) combined with back pain and saddle anaesthesia (numbness in the perineum, inner thighs, and buttocks) constitute cauda equina syndrome — a neurosurgical emergency where spinal cord compression requires decompression within hours to prevent permanent paralysis and loss of continence. Fever with back pain, particularly if accompanied by night sweats and a recent history of intravenous drug use, dental procedure, or immunosuppression, raises concern for spinal infection (epidural abscess or discitis). Back pain in a patient with a known history of cancer should be treated as potential spinal metastasis until proven otherwise. New back pain in a person over 50 without a prior history of back problems, especially combined with unexplained weight loss or progressive neurological deficit, warrants urgent MRI. Back pain following significant trauma in older adults or those on long-term corticosteroids may indicate vertebral fracture.

History and physical examination remain the cornerstone of back pain assessment. The clinician establishes the onset, location, character (sharp, aching, burning, colicky), radiation (into the buttock or below the knee), and exacerbating and relieving factors. Neurological examination assesses deep tendon reflexes (knee and ankle jerks), dermatomal sensation, and limb power. The straight leg raise test — lifting the leg to reproduce sciatica below 60 degrees — indicates L4/L5/S1 nerve root irritation. Routine X-ray is not recommended for acute back pain without red flags, as it rarely changes management and exposes the patient to radiation. MRI is the preferred imaging modality for suspected disc disease, nerve root compression, spinal infection, or malignancy — it provides detailed soft tissue resolution without radiation. CT myelogram is used when MRI is contraindicated. Blood tests including full blood count, CRP, ESR, and PSA (in men over 50) help exclude inflammatory or neoplastic causes.

Most acute back pain resolves with staying active — bed rest is actively harmful and delays recovery. Regular gentle movement, heat application to muscle spasm, and simple analgesics (paracetamol, NSAIDs such as ibuprofen or naproxen) form the first-line approach. Muscle relaxants such as diazepam or cyclobenzaprine are used short-term for severe acute muscle spasm. Physiotherapy with specific exercises targeting spinal stabilisation, flexibility, and core strengthening is the cornerstone of both acute recovery and chronic pain management. Neuropathic pain from disc herniation and nerve root compression may respond to gabapentin or pregabalin. Epidural corticosteroid injections can provide meaningful temporary relief in selected patients with radiculopathy. Spinal cord stimulation is used for refractory chronic pain. Surgery (discectomy for herniated disc, spinal fusion or decompression for stenosis) is reserved for significant, progressive neurological compromise or prolonged failure of comprehensive conservative management. For inflammatory causes such as ankylosing spondylitis, disease-modifying anti-rheumatic drugs (DMARDs) and biologic agents (TNF inhibitors) are the main treatments.

Strengthening the core and paraspinal muscles through regular low-impact exercise is the single most evidence-based strategy for preventing recurrent back pain — swimming, walking, cycling, yoga, and Pilates are all beneficial. Use correct manual handling technique: bend at the knees rather than the waist, keep the load close to the body, avoid twisting while lifting, and never lift more than you can manage safely. Optimise your workstation ergonomics — maintain a neutral spine position when sitting, with feet flat on the floor, monitor at eye level, and take regular standing or walking breaks at least every 30–45 minutes. A supportive mattress of medium firmness is associated with better outcomes for chronic back pain. Maintain a healthy body weight — each kilogram of excess body weight adds disproportionate load to lumbar discs and facet joints. Ensure adequate calcium (1000–1200 mg daily) and vitamin D (at least 800 IU daily) intake to maintain bone density and reduce osteoporotic fracture risk. Address smoking, which impairs disc nutrition through its effects on spinal vasculature.

Call emergency services or go immediately to the nearest emergency department if you develop back pain with any loss of bladder or bowel control, numbness in the saddle area (inner thighs and around the anus), or sudden severe leg weakness — these are signs of cauda equina syndrome, which is a surgical emergency. Seek urgent same-day medical evaluation for back pain with fever (possible spinal infection), back pain following significant trauma or a fall, or back pain with a known or suspected history of cancer. Schedule a priority appointment within a week for back pain lasting more than 4–6 weeks without improvement, pain radiating below the knee, back pain combined with progressive weakness in one or both legs, or back pain in anyone over 50 with no previous history. Routine appointment is appropriate for recurrent low back pain that resolves between episodes but is affecting quality of life. Ongoing self-management with a physiotherapist-guided programme is recommended as first-line treatment for most chronic back pain.