Acute Right-Sided Weakness (OSCE focused) 🧠
Candidate Instructions: You are the medical student on the ward. A 72-year-old patient has been brought in with sudden right arm and leg weakness.
Please take a focused history to identify the likely cause and associated risk factors.
You do not need to examine the patient or discuss management at this stage.
Key Areas to Cover ✅
- Onset & progression: Time of onset (last known well), sudden vs gradual, progression.
- Associated neurological symptoms: speech disturbance, facial droop, visual changes, sensory loss, headache, seizure.
- Stroke risk factors: hypertension, diabetes, AF, smoking, hyperlipidaemia, family history.
- Past medical history: TIA, vascular disease, recent MI, bleeding disorders.
- Drug history: anticoagulants, antiplatelets, antihypertensives, statins.
- Social history: functional baseline, independence, driving, support at home.
- Red flags: thunderclap headache (SAH), trauma, fluctuating symptoms (TIA).
Examiner Prompts 💬
- “What key time points are essential when assessing stroke?”
- “What would you ask to distinguish stroke from a TIA?”
Expected Differential Diagnoses 🔎
- Stroke (ischaemic or haemorrhagic) – most likely given sudden focal neurology.
- TIA – if symptoms have completely resolved.
- Stroke mimics: hypoglycaemia, seizure (post-ictal Todd’s paresis), migraine aura, space-occupying lesion.
Mark Scheme (10 points) 📝
| Domain | Marks | Details |
|---|
| Presenting Complaint | 2 | Clarifies onset, timing, progression, lateralisation. |
| Associated Symptoms | 2 | Speech, vision, swallowing, sensation, headache, seizure. |
| Risk Factors | 2 | Explores AF, HTN, DM, smoking, vascular history. |
| PMHx & DHx | 2 | Past strokes/TIAs, anticoagulant/antiplatelet therapy. |
| Closing | 2 | Summarises, checks for patient concerns, thanks them. |
Teaching Commentary 📚
In stroke OSCEs, the time of onset is absolutely critical ⏱️ - it determines eligibility for thrombolysis or thrombectomy.
Always ask about associated red flags such as thunderclap headache (SAH) or seizures (mimics).
UK exams expect you to remember stroke risk factors (AF, HTN, DM, smoking) and the need to exclude hypoglycaemia.
Finish by gently asking about the patient’s independence, living situation, and concerns - this shows empathy and holistic care.
🧑⚕️ Case Examples - Acute Right-Sided Weakness
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Case 1 (Ischaemic Stroke - Left MCA): 🧠
A 70-year-old man develops sudden right arm and face weakness with expressive aphasia. CT head shows left middle cerebral artery infarct. Diagnosis: Acute ischaemic stroke. Teaching point: Contralateral weakness with cortical signs (aphasia, neglect) localises to MCA territory; consider thrombolysis/thrombectomy if within window.
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Case 2 (Intracerebral Haemorrhage): 💥
A 65-year-old woman with uncontrolled hypertension presents with acute right-sided hemiplegia and reduced GCS. CT head reveals left basal ganglia haemorrhage. Diagnosis: Hypertensive intracerebral haemorrhage. Teaching point: Hypertension is the key risk factor; presents like stroke but CT distinguishes; management is supportive ± neurosurgery.
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Case 3 (Brain Tumour with Seizure): 🎗️
A 55-year-old man develops focal seizure with post-ictal right-sided weakness. MRI brain shows a left frontal mass. Diagnosis: Brain tumour presenting with seizure and Todd’s paresis. Teaching point: Always consider space-occupying lesions in new focal deficits; Todd’s paresis is transient weakness post-seizure but imaging is essential.
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Case 4 (Hypoglycaemia Mimic): 🍬
A 60-year-old diabetic man on insulin is found with confusion and right-sided weakness. Capillary glucose = 2.1 mmol/L. He recovers after IV dextrose. Diagnosis: Hypoglycaemia mimicking stroke. Teaching point: Always check glucose in acute neurological deficit; hypoglycaemia is a reversible stroke mimic.
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Case 5 (Multiple Sclerosis Relapse): 🌿
A 32-year-old woman presents with subacute right-sided weakness and sensory loss over days. MRI brain shows multiple demyelinating plaques. Diagnosis: Relapse of multiple sclerosis. Teaching point: Younger patient with subacute focal neurological deficit → think MS; manage relapses with steroids and consider long-term DMTs.
