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Suspected cauda equina syndrome — MSRA MCQ

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HardMRISuspected cauda equina syndromeMSRA

A 46-year-old man requests an urgent same-day GP assessment for worsening low back pain. For 5 days, he has had severe central lumbar pain radiating down both posterior thighs. Since this morning, he has needed to strain to initiate urination. He also reports new numbness around the anus when wiping after defecation. He has longstanding urinary frequency attributed to benign prostatic enlargement, but has never previously had hesitancy or straining. He is independently mobile. Lower-limb power, reflexes and pinprick sensation are normal. He has no fever, weight loss, recent trauma or history of malignancy. He has no contraindication to MRI. What is the most appropriate management today?

Educational content. Not a substitute for clinical judgement or local policy.

Reveal the answer and explanation

Correct answer: E — Refer immediately through the local suspected cauda equina pathway for emergency assessment and urgent MRI

Explanation lettering: C = shown as A · A = shown as B · B = shown as C

This man requires immediate referral for suspected cauda equina syndrome (CES). The key linked findings are severe back pain radiating into both legs, an acute change in bladder function (new hesitancy and straining rather than his baseline urinary frequency), and new perineal sensory disturbance. NICE advises immediate referral via local pathways when severe low back pain radiating into the leg is accompanied by new bladder, bowel or sexual dysfunction, or new perineal numbness. His preserved mobility and normal lower-limb power, reflexes and distal pinprick sensation do not remove the indication for emergency CES assessment because he meets the specified bladder and perineal symptom criteria. The purpose of referral is prompt specialist assessment and urgent MRI through the acute local pathway, with timely escalation if compressive CES is confirmed. A is attractive because MRI is required, but outpatient imaging risks an inappropriate delay. B is plausible because benign prostatic enlargement can cause lower urinary tract symptoms; however, it does not explain the new saddle sensory change with bilateral radicular pain, and urological assessment must not delay exclusion of CES. C incorrectly substitutes observation and serial examination for immediate escalation. D uses a non-emergency referral timescale that is incompatible with suspected CES.

Reference: Suspected neurological conditions: recognition and referral (NG127), Recommendations for adults aged over 16 (Published May 2019; last updated 2 October 2023) — https://www.nice.org.uk/guidance/ng127/chapter/Recommendations-for-adults-aged-over-16