Vertebral Column Anatomy and Clinical Correlates

Also written as spine, backbone.

The vertebral column provides structural support, protects the spinal cord and enables movement. Understanding its segments, common pathologies and bedside assessment is essential for safe patient care in low‑resource settings.

Overview

The spine consists of 33 vertebrae grouped into cervical (7), thoracic (12), lumbar (5), sacral (5 fused) and coccygeal (4 fused) regions. Intervertebral discs, ligaments and muscles allow flexibility while protecting the spinal cord within the vertebral canal.

• Cervical vertebrae have transverse foramina for vertebral arteries.
• Thoracic vertebrae articulate with ribs; limited flexion.
• Lumbar vertebrae are largest, bear most weight.

Key concepts

Clinicians must link vertebral level to neurological findings, recognise red‑flag signs of spinal infection or trauma, and understand how low‑resource constraints affect diagnosis.

• Dermatomal maps guide localisation of cord or nerve root injury.
• Spinal tenderness plus fever = possible spinal infection (TB, pyogenic).
• Trauma with focal neurological deficit → consider vertebral fracture.

Clinical relevance

Common conditions in East African hospitals include spinal tuberculosis, traumatic fractures from road traffic accidents, and degenerative disc disease presenting as low back pain. HIV and sickle cell increase infection risk.

• Plain radiograph (AP & lateral): Detects vertebral collapse, fracture lines, gibbus; if unavailable, rely on clinical suspicion and refer for CT/MRI when possible.
• MRI (if available): Identifies epidural abscess, cord compression, discitis; if unavailable, treat presumptively for TB if red‑flag symptoms present.
• ESR/CRP: Screen for inflammation; markedly raised ESR supports spinal TB but is non‑specific.

• Spinal TB: insidious back pain, night sweats, weight loss; may cause gibbus deformity.
• Traumatic burst fracture: severe back pain, possible spinal cord compression, bladder dysfunction.
• Degenerative disc disease: chronic low back pain, worsened by activity, improves with rest.

Exam pearls

A focused spinal exam can differentiate mechanical pain from neuro‑genic or infectious causes.

• Inspect for deformity, scars, or skin changes.
• Palpate vertebral tenderness; midline tenderness suggests infection or fracture.
• Assess motor strength and sensation in key dermatomes (C5‑T1, L2‑S1).
• Test reflexes (biceps, triceps, knee, ankle) for upper vs lower motor signs.

Common mistakes

Errors often arise from over‑reliance on imaging, missing red‑flag signs, or mis‑localising pain.

• Assuming all low back pain is mechanical; ignore fever or weight loss.
• Failing to assess for spinal cord compression before mobilising a trauma patient.
• Using plain X‑ray alone to rule out TB when early disease may be radiographically silent.

Questions an examiner may ask

• A 30‑year‑old HIV‑positive man presents with 3 months of mid‑back pain, night sweats and a gibbus. What is the most likely diagnosis and next step? — Recognise spinal TB; obtain MRI if possible, start anti‑TB therapy, arrange surgical review for deformity.
• A motorbike accident victim has lumbar tenderness and loss of ankle reflexes. What does this indicate and how should you act? — Suggests possible cauda equina injury; immobilise spine, urgent imaging, consult neurosurgery.
• A patient with chronic low back pain improves when lying flat. Which condition is most likely and what is the first-line management? — Mechanical low back pain; advise activity modification, NSAIDs, physiotherapy.
• During a routine exam you note a positive Lasègue’s sign at 30°. What does this tell you? — Indicates nerve root irritation, likely disc herniation; consider MRI if severe or progressive.
• You suspect spinal TB but MRI is unavailable. Which investigations can still support the diagnosis? — Plain X‑ray for vertebral collapse, ESR/CRP elevation, TB skin test or GeneXpert on sputum if pulmonary involvement.
• A patient on long‑term steroids presents with acute back pain and fever. What condition must you exclude and why? — Spinal epidural abscess; requires urgent MRI and possible surgical drainage.
• What is the significance of a “gibbus” deformity? — Sharp angular kyphosis typical of advanced thoracic TB; indicates vertebral body collapse and risk of cord compression.
• Why should high‑dose steroids be avoided in a patient with suspected spinal infection? — Steroids suppress immunity and may worsen infection; they are contraindicated unless indicated for another condition.

When to seek help

• Progressive neurological deficit (weakness, numbness, bowel/bladder loss)
• Severe back pain with fever or night sweats
• Suspected spinal fracture with instability

Quick questions

What bedside sign suggests spinal cord compression?

New onset weakness or sensory loss below a spinal level, often with a brisk reflex and positive Babinski.

Why is ESR useful in spinal TB?

It is usually markedly elevated, supporting an inflammatory process, though it is not diagnostic alone.

Can low back pain be safely managed without imaging?

Yes, if no red‑flag features are present; treat conservatively and reassess if symptoms persist beyond 6 weeks.