Back pain
Most common reason adults see a primary-care doctor. Vast majority (>90%) is non-specific musculoskeletal and resolves within 6 weeks. Lab role is to catch the small group with inflammatory, infectious, malignant or metabolic causes — not the mechanical pain itself.
What it means
Back pain is pain anywhere from the cervical to the sacral spine; 'low back pain' specifically refers to the lumbar region. Three clinical patterns: (1) mechanical / non-specific — sudden onset after activity, worse with movement, better at rest, no systemic features. >90% of cases. (2) Inflammatory — gradual onset, worse at night and in the morning, improves with movement, often in young men (axial spondyloarthritis). (3) Sinister (red-flag) — constant pain unaffected by position, weight loss, fever, night sweats, neurological deficit, history of cancer. Sinister pain demands urgent imaging and bloods; mechanical pain doesn't.
Common causes
- Non-specific musculoskeletal strain — by far the commonest; ligament, muscle, disc.
- Disc herniation with radiculopathy — pain radiating down a leg in a dermatomal pattern.
- Spinal stenosis — older adults, leg pain with walking, relieved by leaning forward.
- Osteoporotic vertebral fracture — sudden severe pain in postmenopausal women / men >70.
- Inflammatory back pain (axial spondyloarthritis) — young adults, gradual onset, morning stiffness >30 min.
- Vertebral osteomyelitis / discitis — fever, IV drug use, recent bacteraemia.
- Malignancy (myeloma, metastases, primary spinal) — weight loss, night pain, history of cancer.
- Renal colic, pyelonephritis — flank pain radiating to back; check urine.
- Aortic aneurysm rupture / dissection — sudden tearing pain, hypotension — emergency.
Lab work-up approach
Routine mechanical back pain needs no labs. Order bloods when red flags or no improvement at 4–6 weeks: full blood count (anaemia of chronic disease, leucocytosis in infection), CRP + ESR (inflammatory or infectious), calcium + alkaline phosphatase (bone metastases, Paget's), HLA-B27 (suspected spondyloarthritis), serum / urine protein electrophoresis (myeloma in older adults with bone pain), vitamin D (severe deficiency causes diffuse skeletal pain). Imaging (X-ray, MRI) for red flags or persistent radiculopathy. Mediora.AI surfaces the inflammatory / metabolic / haematological labs; mechanical-cause workup is GP + physio.
Tests Mediora.AI can interpret
Related conditions
When to see a doctor
Same-day medical attention: new severe back pain with leg weakness or numbness, urinary / faecal incontinence or retention (cauda equina — surgical emergency), sudden 'tearing' chest-and-back pain (aortic dissection), fever + back pain, history of cancer + new back pain. GP review within days: back pain unchanged at 4 weeks, night pain, unexplained weight loss with back pain, inflammatory features (worse at night, morning stiffness, age <45). Self-managed (NSAIDs, gentle activity, heat) is appropriate for typical mechanical pain with no red flags. Mediora.AI helps screen for the medical mimics.