Spinal cord compression
Back pain in someone with cancer is cord compression until proven otherwise. Act on the pain, before the weakness.
A 66-year-old man with prostate cancer has had worsening mid-back pain for 3 weeks, worse lying down and at night. Today his legs feel heavy and he is unsteady. Power 4/5 in both legs, brisk reflexes, sensory level at T10. He has not passed urine since the morning.
What do you give now, what scan, and how fast?
- Suspect itKnown cancer with back pain plus any neurological symptom.
- Dexamethasone now16 mg orally or IV, with a PPI.
- MRI of the whole spineWithin 24 hours (sooner if possible) with neurological signs, within 1 week for pain alone.
- Lie flat if unstable or severe painLog-roll until stability is known.
- BladderBladder scan, catheter if retaining.
- Discuss with the MSCC coordinator, oncology, spinal surgeonsSurgery or radiotherapy.
- Prevent complicationsVTE prophylaxis, pressure care, bowels, glucose on steroids.
- New leg weakness or numbness
- Bladder or bowel problems
- Sensory level
- Rapid progression
- Pain worsening despite treatment
- Cord compression in an unknown cancer
- Cauda equina syndrome
- Spinal abscess or TB (Pott's spine)
- Epidural haematoma
- Steroid hyperglycaemia
| Dexamethasone | 16 mg once (oral or IV), then 16 mg daily in divided doses |
| MRI | Whole spine, within 24 hours with neurological signs, within 1 week for pain alone |
| Most common level | Thoracic spine |
| Common primaries | Lung, breast, prostate, kidney, myeloma |
| Outcome | Walking ability at diagnosis predicts walking after treatment |
| Steroids | Add a PPI, check glucose |
Check every dose against a current drug reference and your hospital protocol.
On this page
Who gets it?
- Known cancer, especially lung, breast, prostate, kidney, myeloma, lymphoma.
- Up to a quarter present with no known cancer diagnosis.
- Non-cancer causes in Pakistan: spinal TB, epidural abscess, disc prolapse, trauma.
Warning symptoms
- Pain in the thoracic or upper lumbar spine.
- Progressive, severe, or not responding to analgesia.
- Worse lying flat, at night, or on coughing or straining.
- Band-like pain around the chest or abdomen.
- Localised spinal tenderness.
- Leg weakness, heaviness, unsteadiness.
- Numbness, a sensory level.
- Urinary retention or incontinence.
- Constipation or faecal incontinence.
- Brisk reflexes and upgoing plantars (upper motor neuron) above L1; reduced reflexes at the cauda equina.
Management
- Dexamethasone 16 mgNow, with a PPI.
- MRI whole spineWithin 24 hours with neurological signs; within 1 week for suggestive pain without signs.
- Spinal precautionsFlat and log-roll if severe pain or suspected instability.
- Bladder and bowelsBladder scan, catheter, laxatives.
- Definitive treatmentSurgery (decompression and stabilisation) or radiotherapy, decided by spinal surgeons and oncology.
Differential diagnosis
| Condition | Clues |
|---|---|
| Cauda equina syndrome | Saddle numbness, bladder, low back |
| Spinal TB | Fever, weight loss, gibbus, young adults |
| Epidural abscess | Fever, injecting drug use, diabetes |
| Disc prolapse | Younger, sciatica |
| Vertebral fracture | Osteoporosis, myeloma |
| Guillain-Barré | Ascending weakness, absent reflexes, no sensory level |
| Transverse myelitis | Rapid onset, no compression on MRI |
Investigations
| Test | Why |
|---|---|
| MRI whole spine | Diagnosis and level (often more than one) |
| FBC, U&E, calcium, LFT | Hypercalcaemia, staging |
| PSA, myeloma screen, chest X-ray | Unknown primary |
| Glucose | Before and during steroids |
| CT | If MRI not possible |
Treatment
See cauda equina and back pain.
Common mistakes
- Waiting for weakness before scanning.
- Scanning only the painful part of the spine.
- Forgetting dexamethasone.
- Not checking the bladder.
- Missing spinal TB in a young patient with back pain and weight loss.
- Not monitoring glucose on high-dose steroids.
Frequently asked questions
What dose of dexamethasone is used in spinal cord compression?
16 mg once, orally or IV, then 16 mg daily, with a PPI.
Which part of the spine is most often affected?
The thoracic spine.
How quickly should an MRI be done?
Within 24 hours if there are neurological signs, and within 1 week for suggestive pain alone.
What predicts walking after treatment?
Being able to walk at the time of diagnosis.
Test yourself
Exam-style questions on this guide, from our two question banks. Choose an answer to see why each option is right or wrong.
1. A man with prostate cancer has 2 weeks of thoracic back pain and new leg heaviness. What is the most urgent investigation?
Answer: Immediate whole-spine MRI. Suspected metastatic cord compression with neurological symptoms needs immediate MRI of the whole spine.
- Plain X-ray of the spine: Can miss compression.
- MRI within 2 weeks: Too slow with neurology.
- PSA: Doesn't change urgent management.
- Bone scan: Doesn't show cord compression.
2. What dose of dexamethasone is given in suspected metastatic spinal cord compression?
Answer: 16 mg daily. Dexamethasone 16 mg daily with a PPI and glucose monitoring until definitive treatment.
- 100 mg daily: Too high.
- No steroids: Steroids are recommended.
- 0.5 mg daily: Too low.
- 4 mg once only: Too low.
3. Which finding favours spinal cord compression over cauda equina syndrome?
Answer: Sensory level, brisk reflexes. Cord compression causes upper motor neuron signs and a sensory level; cauda equina causes lower motor neuron signs and saddle numbness.
- Bilateral sciatica: Cauda equina.
- Saddle anaesthesia: Typical of cauda equina.
- Reduced anal tone: Both can have it.
- Absent ankle reflexes: Lower motor neuron.
4. A man with prostate cancer has new back pain, bilateral leg weakness and urinary retention. What should be given immediately?
Answer: High-dose dexamethasone. Malignant spinal cord compression (breast, lung, prostate, renal, myeloma) is an oncological emergency. Give dexamethasone 16 mg/day with PPI, urgent whole-spine MRI within 24 h, and definitive treatment (radiotherapy or decompressive surgery) within 24 h. Ambulatory status at treatment predicts outcome. Back pain in a cancer patient — especially thoracic or worse lying down — is a red flag.
- NSAIDs and physiotherapy: NSAIDs do not treat cord compression.
- Outpatient MRI in 2 weeks: Cord compression is an emergency.
- Bed rest only: Bed rest does not treat compression.
5. A 15-year-old with recent frontal sinusitis develops a soft, tender, doughy swelling in the middle of his forehead with fever and headache. What is this and what is the concern?
Answer: Pott’s puffy tumour. Pott’s puffy tumour: complication of frontal sinusitis (or trauma) — frontal bone osteomyelitis with subperiosteal abscess presenting as a soft forehead swelling; mostly in adolescents (developing frontal sinus with rich diploic venous system). Spread via valveless diploic veins causes epidural abscess, subdural empyema, meningitis, brain abscess, cavernous sinus thrombosis — frequently coexisting. Investigations: contrast CT and MRI brain. Treatment: prolonged IV antibiotics (covering streptococci, staphylococci and anaerobes — e.g. ceftriaxone + metronidazole ± vancomycin) for 6–8 weeks, surgical drainage of abscess, debridement of necrotic bone and sinus surgery; neurosurgery for intracranial collections. Not a tumour — named after Percivall Pott.
- Sebaceous cyst: A sebaceous cyst is not acute or tender.
- Frontal lipoma: A lipoma is not febrile.
- Periorbital cellulitis: Periorbital cellulitis affects the eyelids, not the forehead.
6. A line joining the highest points of the iliac crests crosses which vertebral level, used to find the space for a lumbar puncture?
Answer: L4. The supracristal (Tuffier's) line crosses the L4 spinous process or the L4/5 interspace. Lumbar puncture is done at L3/4 or L4/5, safely below the end of the spinal cord (L1/2 in adults, L3 in newborns).
- L1: The transpyloric plane and the cord's end in adults.
- T12: The level of the coeliac trunk and 12th rib.
- S2: The end of the dural sac and the posterior superior iliac spines.
- L2: Too high; the conus ends near here.
7. An elderly man with prostate cancer develops lumbar back pain. Bone scan shows vertebral metastases. Through which route did the cancer most likely spread?
Answer: Batson's vertebral venous plexus. The prostatic venous plexus connects with the valveless vertebral venous plexus. When abdominal pressure rises (coughing, straining), blood and tumour cells can flow directly into the vertebrae, skipping the lungs. Prostate metastases are typically osteoblastic (sclerotic).
- Thoracic duct: Lymphatic route; not the main route to the spine.
- Portal vein: Drains the gut, not the prostate.
- Via the IVC to the lungs first: Would seed lungs first.
- Direct invasion through the rectum: Denonvilliers' fascia usually blocks this.
References and dose sources
- NICE NG234: Spinal metastases and metastatic spinal cord compression
- Dexamethasone dosing: Drugs.com: Dexamethasone dosage (see also our dexamethasone dose page)
- Omeprazole dosing: Drugs.com: Omeprazole dosage (see also our omeprazole dose page)
- Morphine dosing: Drugs.com: Morphine dosage (see also our morphine dose page)
- Enoxaparin dosing: Drugs.com: Enoxaparin dosage (see also our enoxaparin dose page)
International guidance is linked where it reflects good practice. Where your hospital’s protocol differs, follow your hospital.