Station Title & Timing
- Title: Lower Limb Motor Weakness – Transient Ischemic Attack (TIA)
- Duration: 10 Minutes (2 minutes reading time, 8 minutes performance)
Learning Objective(s)
- Perform a focused motor neurological examination of the lower limbs.
- Demonstrate clinical reasoning by performing “relevant” systemic checks (Cardiovascular/Carotid).
- Communicate a provisional diagnosis and differential diagnoses using patient-centered language.
Patient Profile
- Name: Mr. Arthur Thompson
- Age: 68 years old
- Gender: Male
- Ethnicity: Caucasian
- Occupation: Retired Accountant
- Social History: Lives with his wife; non-smoker; drinks 1-2 glasses of wine on weekends.
Presenting Complaint
Mr. Thompson presented to the GP clinic this morning because he experienced a sudden onset of “heaviness” and weakness in his right leg about two hours ago while gardening. The feeling lasted for approximately 15 minutes and has now completely resolved.
Contextual Information
- HPC: Sudden right leg weakness; no associated facial drooping or arm weakness. No speech difficulties. No loss of consciousness. This is the first time this has happened.
- PMH: Hypertension (well-controlled), Hyperlipidemia.
- Medications: Amlodipine 5mg, Atorvastatin 20mg.
- Allergies: Nil known.
- Family History: Father died of a stroke at age 75.
Exam Instructions
Candidate Instructions
Arthur Thompson is a 68-year-old male who experienced transient right-sided leg weakness earlier today. His symptoms have now resolved.
- Perform a focused Lower Limb Motor Neurological Examination.
- Perform any other relevant systemic examinations based on the clinical context.
- Discuss your provisional diagnosis and two differential diagnoses with the patient.
- Briefly explain the nature of the condition to the patient.
Note: You are not required to perform sensory or coordination testing.
Standardised Patient (SP) Instructions
- Demeanor: You are slightly anxious but calm. You are currently asymptomatic (the weakness is gone).
- Role-Play: If the candidate asks how you feel, say “I feel fine now, but it was very frightening when my leg just wouldn’t move properly.”
- Examination: Follow the candidate’s instructions. If they test your “Power,” provide full resistance (since symptoms have resolved).
Examiner Checklist Items
- Introduces self and obtains consent.
- Ensures patient is appropriately positioned and exposed.
- Performs I-T-P-R sequence (Inspection, Tone, Power, Reflexes) bilaterally.
- Provides a running commentary of Myotomes (L2-S1).
- Performs Carotid Auscultation (identifies need to check for bruits).
- Performs Cardiac Auscultation/Pulse (identifies need to check for AF).
- Explains TIA using the “mini-stroke” analogy.
Key Clinical Findings
- Vitals: BP 145/90 mmHg, Pulse 82 bpm (Regular), Temp 37°C.
- Inspection: No muscle wasting or fasciculations.
- Tone: Normal bilaterally in hip, knee, and ankle.
- Power: 5/5 bilaterally in all muscle groups (L2-S1).
- Reflexes: 2+ (normal) at patellar (L3/4) and Achilles (S1/2) tendons.
- Systemic: No carotid bruits. S1, S2 heard, no murmurs.
Communication Triggers (Murtagh’s Approach)
- Open-ended start: “Mr. Thompson, can you tell me in your own words what happened earlier today?”
- Summarising: “So, to make sure I’ve got this right, your right leg felt heavy for 15 minutes, but now it feels back to normal. Is that correct?”
- Lay Language: Avoid “Transient Ischemic Attack” initially; use “mini-stroke” or “temporary blockage.”
- Empathy: “I can understand why that would be a very frightening experience for you.”
Assessment & Marking Guide
| Domain | Key Performance Indicators |
| Motor Exam | Correct sequence: Inspection $\rightarrow$ Tone $\rightarrow$ Power $\rightarrow$ Reflexes. Conducted bilaterally. |
| Myotomes | Explicitly mentions L2 (Hip Flexion), L3 (Knee Extension), L4 (Knee Flexion), L5 (Dorsiflexion), S1 (Plantarflexion). |
| Systemic Checks | C-A-P: Auscultates Carotids, checks Pulse for AF, checks Heart Sounds. |
| Diagnosis | Correctly identifies TIA and provides differentials (e.g., Todd’s Paralysis, MS, Hypoglycemia). |
| Communication | Explains the “clot/narrowing” mechanism clearly without jargon. |
Sample Answers / Model Performance
Suggested Running Commentary (Power):
“I am now checking Hip Flexion which tests the L2 nerve root… Now checking Knee Extension for L3… Knee Flexion for L4… I am checking Dorsiflexion of the foot for L5… and finally Plantarflexion, pressing down like a gas pedal, for S1.”
Explaining the Diagnosis:
“Mr. Thompson, based on what you’ve told me and my examination, it appears you’ve had what we call a Transient Ischemic Attack, often referred to as a ‘mini-stroke’. This happens when the blood supply to a part of your brain is briefly interrupted, usually by a tiny blood clot or a narrowing in the blood vessels in your neck. Because the blood flow returned quickly, your symptoms disappeared, but we need to do some tests to prevent a full stroke in the future.”