Gait abnormality is one of those presentations that quietly separates the careful registrar from the premature diagnostician. It arrives in the emergency department wrapped in ambiguity: a frail octogenarian who “went off their legs”, a child refusing to weight-bear, or a middle-aged man whose spouse noticed he had been walking “oddly” for a week. The differential spans benign musculoskeletal pathology at one end and immediately life-threatening posterior fossa haemorrhage at the other. For trainees working through FRCEM SBA practice questions, gait abnormality is a recurring theme precisely because it demands the kind of structured, anatomically-grounded reasoning that the exam is designed to test. Understanding this topic thoroughly rewards you both clinically and in the examination room.
FRCEM SBA practice questions: Key Points
- Gait abnormality must be classified by anatomical level (cortical, cerebellar, spinal, peripheral nerve, neuromuscular, musculoskeletal, vestibular) before a coherent differential is constructed.
- Central causes of acute gait disturbance, particularly posterior fossa stroke and cerebellar haemorrhage, are disproportionately dangerous and must be actively excluded before attributing unsteadiness to peripheral or benign causes.
- The HINTS examination (Head Impulse, Nystagmus, Test of Skew) is a validated bedside tool for differentiating central from peripheral vestibular pathology in acute continuous vertigo with gait disturbance.
- Red flag features mandating urgent neuroimaging include acute onset, headache, vomiting, truncal ataxia, direction-changing nystagmus, new cranial nerve signs, and immunosuppression or malignancy history.
- In children, septic arthritis must be distinguished from toxic synovitis urgently: Kocher criteria and inflammatory markers guide risk stratification, and delay risks avascular necrosis.
- Multifactorial gait disorder in the elderly is common but remains a diagnosis of exclusion in the acute setting: polypharmacy review is mandatory.
Clinical Context and Epidemiology
Gait abnormality is among the most common reasons for attendance in elderly patients and a significant contributor to falls-related morbidity. NICE guidance on falls in older people recognises that impaired gait and balance are major modifiable risk factors, but the acute ED encounter demands more than falls prevention counselling. Studies of acute dizziness and unsteadiness consistently show that central nervous system pathology, including posterior fossa stroke, cerebellar haemorrhage, and spinal cord compression, accounts for a clinically important minority of presentations that carry catastrophic consequences when missed.
Across age groups, the aetiology shifts substantially. In children, toxic synovitis and trauma predominate, but septic arthritis, transient synovitis mimics such as leukaemia, and posterior fossa tumours require consideration. In working-age adults, acute disc prolapse with cord or cauda equina involvement, multiple sclerosis relapse, and Guillain-Barre syndrome enter the differential. In the elderly, the picture is frequently multifactorial: sarcopenia, vestibular degeneration, visual impairment, peripheral neuropathy, and polypharmacy interact to erode gait stability. Antihypertensives, benzodiazepines, and opioids are particularly implicated, and medication reconciliation is a core ED task.
Anatomical Classification: The Foundation of Safe Reasoning
The most reliable method for structuring the gait abnormality differential is anatomical localisation. Each level of the neuraxis produces characteristic gait patterns that the examiner can identify at the bedside, and the FRCEM SBA exam routinely tests whether candidates can match clinical features to the correct anatomical level.
Cortical and Subcortical Pathology
Lesions at this level produce a broad-based, shuffling, “magnetic” gait with preserved arm swing in frontal lobe pathology (as in normal-pressure hydrocephalus), or a hemiparetic gait with ipsilateral arm flexion and leg circumduction following stroke in middle cerebral artery territory. Subcortical small vessel disease produces a “cautious” or “lower-body” gait disorder with short steps and freezing, clinically overlapping with Parkinsonism. Acute cortical presentations, particularly haemorrhagic or ischaemic stroke, present with additional features: unilateral weakness, facial droop, dysarthria, or neglect.
Cerebellar and Brainstem Pathology
Cerebellar pathology produces a wide-based, staggering, ataxic gait with impaired tandem walking and past-pointing on finger-nose testing. Crucially, truncal ataxia, the inability to sit or stand unsupported, indicates a midline cerebellar lesion and carries a high probability of serious structural pathology. Posterior fossa stroke and haemorrhage are the most urgent considerations. Wernicke encephalopathy, precipitated by thiamine deficiency in malnourished or alcohol-dependent patients, produces the classical triad of ophthalmoplegia, ataxia, and confusion, though all three features are present simultaneously in fewer than 20% of cases. Empirical thiamine replacement is justified when Wernicke encephalopathy is suspected, and the British National Formulary recommends parenteral thiamine (Pabrinex) administered before any glucose-containing fluid in at-risk patients.
Spinal Cord and Cauda Equina
Cord compression above the conus produces a spastic paraparesis with a scissor gait, hyperreflexia, upgoing plantars, and a sensory level. The key emergency is cauda equina syndrome (CES), which presents with lower limb weakness, saddle anaesthesia, and bladder or bowel dysfunction. CES is a surgical emergency and requires urgent MRI of the entire spine followed by immediate neurosurgical referral. NICE guidance is clear that suspected CES mandates same-day specialist assessment.
Peripheral Nerve and Neuromuscular
Foot drop from common peroneal nerve palsy produces a high-stepping (steppage) gait. Bilateral ascending weakness with areflexia raises the spectre of Guillain-Barre syndrome (GBS), in which gait disturbance may precede respiratory compromise: serial FVC measurement is mandatory. Myasthenic gait, worsening with exertion, may be accompanied by ptosis, diplopia, and dysarthria.
ED Assessment: History, Examination, and Investigation
History
Onset characterisation is paramount. Hyperacute onset (seconds to minutes) points to vascular causes: stroke, haemorrhage, or transient ischaemic attack. Subacute onset over hours to days suggests inflammatory demyelination, infection, or metabolic disturbance. Chronic and progressive deterioration is more consistent with degenerative, neoplastic, or nutritional aetiology. Associated symptoms demand systematic enquiry: headache and vomiting with cerebellar signs suggest raised intracranial pressure or posterior fossa lesion; saddle anaesthesia and urinary retention demand immediate CES workup; fever and back pain with cord signs raise the possibility of spinal epidural abscess, a neurosurgical emergency that is frequently misdiagnosed on first contact.
Examination
A targeted neurological examination is non-negotiable. Observe the patient walking if clinically safe. Assess Romberg’s sign: positive (worsening with eyes closed) implicates dorsal column or vestibular pathology rather than cerebellar disease. Tandem gait testing is sensitive for midline cerebellar dysfunction. Upper and lower motor neurone signs, sensory level, reflexes, and cranial nerve examination complete the neurological survey.
The HINTS examination, validated for use in patients with acute, continuous vertigo accompanied by gait instability, comprises three components: the Head Impulse Test (abnormal catch-up saccade suggests peripheral pathology), the assessment of Nystagmus (direction-changing nystagmus is a central sign), and the Test of Skew (vertical skew deviation indicates central pathology). A HINTS examination demonstrating a normal head impulse, direction-changing nystagmus, or skew deviation is more sensitive for posterior fossa stroke than early MRI DWI in the first 24 to 48 hours, a fact heavily tested in FRCEM SBA exam questions.
Investigations
Point-of-care blood glucose must be checked in every patient with acute neurological disturbance. A full metabolic screen, including electrolytes, renal function, liver function, FBC, CRP, and coagulation, guides management of systemic and metabolic causes. Thiamine and B12 levels should be requested where deficiency is suspected, though treatment must not be delayed pending results. CT head without contrast is the first-line neuroimaging modality for suspected intracranial haemorrhage, mass lesion, or hydrocephalus. CT is insensitive for early posterior fossa ischaemic stroke: MRI with DWI is the gold standard and should be requested urgently in suspected cerebellar or brainstem stroke even when CT is normal. Lumbar puncture, preceded by CT where indicated, is required when subarachnoid haemorrhage or CNS infection remains in the differential despite negative initial imaging.
How the FRCEM SBA Exam Tests Gait Abnormality
The Royal College of Emergency Medicine FRCEM SBA curriculum encompasses neurology presentations across all age groups, and gait abnormality appears across multiple domains: acute stroke and TIA, spinal emergencies, paediatric limping child, and toxicological presentations. Candidates working through FRCEM SBA practice questions consistently encounter stems that require distinguishing central from peripheral causes of ataxia, identifying the correct investigation sequence in suspected CES, and selecting the appropriate initial management step for Wernicke encephalopathy.
Common question archetypes include: a patient with acute onset gait ataxia and vomiting where the correct answer requires recognising that a normal CT does not exclude posterior fossa stroke and that MRI DWI is indicated; a patient with bilateral leg weakness and urinary retention where the single best answer is urgent MRI spine rather than catheterisation alone; and a child with a two-week history of limp and fever where the Kocher criteria guide whether immediate orthopaedic referral or watchful waiting is appropriate. The FRCEM SBA exam rewards candidates who apply a structured anatomical framework rather than pattern-matching superficially to the most memorable diagnosis.
Candidates preparing for the FRCEM SBA exam should also be comfortable with the pharmacological management of specific conditions encountered in this presentation: empirical Pabrinex dosing, dexamethasone in cord compression from malignancy, and the role of intravenous immunoglobulin in GBS. These frequently appear as management-focused stems.
Revision Pearls: High-Yield Facts for the FRCEM SBA
- Truncal ataxia is a neurosurgical red flag. Inability to sit unsupported with acute onset implies a midline cerebellar lesion and mandates urgent CT or MRI with neurosurgical involvement.
- HINTS outperforms early MRI DWI for posterior fossa stroke in the first 24 to 48 hours when performed by a trained examiner. A normal head impulse test in continuous vertigo should raise, not lower, your suspicion for central pathology.
- Wernicke encephalopathy is underdiagnosed. The full triad is present in fewer than 20% of cases. Any at-risk patient with neurological signs should receive IV Pabrinex before glucose administration.
- Cauda equina syndrome is a time-critical surgical emergency. Urinary retention with a post-void residual greater than 100 mL in the context of back pain and lower limb symptoms is CES until proven otherwise.
- In children, the limping child protocol applies to gait refusal. Kocher criteria (fever, non-weight-bearing, ESR greater than 40 mm/h, WBC greater than 12) predict probability of septic arthritis; three or four criteria warrant urgent orthopaedic referral.
- Guillain-Barre syndrome can present with gait instability before weakness is overt. Areflexia is an early and reliable sign. Serial FVC is essential as respiratory failure may develop rapidly.
- Spinal epidural abscess is frequently missed on initial ED assessment. The triad of fever, back pain, and neurological deficit is a red flag for immediate MRI spine and infectious disease or spinal surgical consultation.
Common Pitfalls: Where Candidates Lose Marks
- Accepting a normal CT head as sufficient to exclude posterior fossa stroke and discharging the patient without MRI or senior review.
- Attributing acute ataxia to alcohol intoxication without a full examination and blood glucose: Wernicke encephalopathy and hypoglycaemia are both treatable and both carry a normal-appearing superficial appearance.
- Failing to assess for saddle anaesthesia and post-void residual bladder volume in patients presenting with back pain and bilateral leg symptoms.
- Diagnosing a peripheral vestibular cause of gait disturbance without performing or documenting a HINTS examination.
- Overlooking polypharmacy as a contributing factor in elderly gait disturbance and failing to perform a medication reconciliation.
- Confusing positive Romberg’s sign (dorsal column or vestibular) with cerebellar ataxia, which is present with eyes open and does not significantly worsen on eye closure.
How EM Learning Centre Supports Your FRCEM Single Best Answer Revision
Gait abnormality is a topic where surface-level knowledge is genuinely dangerous, both clinically and in the examination. The structured, case-based approach used in the FRCEM Single Best Answer revision course at EM Learning Centre is designed precisely to build the anatomical reasoning and red-flag recognition that the exam, and your patients, demand. Each lesson integrates clinical context, pathophysiology, investigation strategy, and management into a format that mirrors real SBA stems, so that FRCEM SBA practice questions reinforce understanding rather than encouraging rote memorisation.
The platform covers the full breadth of the FRCEM SBA syllabus, including neurological emergencies, paediatric presentations, toxicology, trauma, and resuscitation, all aligned with current RCEM curriculum standards. Whether you are building your first structured revision plan or refining your approach in the weeks before the exam, the EM Learning Centre provides the depth and clinical accuracy that distinguishes genuinely effective FRCEM SBA revision from passive reading. Consistent engagement with high-quality, explained practice questions remains one of the most reliable predictors of exam success, and it is the foundation on which this platform is built.
References
- Royal College of Emergency Medicine. FRCEM curriculum and assessment framework. rcem.ac.uk
- National Institute for Health and Care Excellence. Falls in older people: assessing risk and prevention. Clinical guideline CG161. nice.org.uk
- British National Formulary. Thiamine (Pabrinex): prescribing and dosing information. bnf.nice.org.uk
- Newman-Toker DE, Kattah JC, Alvernia JE, Wang DZ. Normal head impulse test differentiates acute cerebellar strokes from vestibular neuritis. BMJ referenced via bmj.com
- Royal College of Paediatrics and Child Health. Standards and guidance for paediatric emergency care. rcpch.ac.uk
