# Clinical Cases: Neurological Examination ## Case 1: Upper Motor Neuron Lesion (Hemispheric Stroke) ### Patient Presentation **Demographics:** 68-year-old right-handed male **Chief Complaint:** Left arm and leg weakness **History of Present Illness:** The patient was found by his wife with weakness on his left side. She last saw him normal 3 hours ago when she left to run errands. Upon return, he was sitting in his chair but could not lift his left arm and had slurred speech. He has a history of hypertension (poorly controlled), type 2 diabetes, and former smoking. **Systematic Neurological Examination:** **Mental Status:** - Level of consciousness: Alert - Attention: Intact; follows commands appropriately - Orientation: Oriented to person, place, and time - Language: Speech slightly dysarthric; naming, repetition, and comprehension intact - Neglect testing: When asked to identify objects in left visual field, patient occasionally misses items; extinction to double simultaneous stimulation (extinguishes left side) **Cranial Nerves:** - II: Visual acuity grossly intact; left homonymous hemianopia on confrontation (misses fingers in left visual fields of both eyes) - III, IV, VI: Pupils equal and reactive; eyes deviate to the RIGHT (toward the lesion); full range of motion when tested - V: Sensation intact bilaterally - VII: Left lower facial weakness (flattened nasolabial fold, droop of mouth corner); able to wrinkle forehead bilaterally (forehead SPARED - UMN pattern) - VIII-XII: Intact **Motor Examination:** - Inspection: No atrophy; no fasciculations - Tone: Left arm and leg have increased tone with spasticity (velocity-dependent catch) - Strength (MRC scale): - Right upper extremity: 5/5 - Right lower extremity: 5/5 - Left upper extremity: 2/5 (deltoid, biceps, triceps, wrist extensors, grip) - Left lower extremity: 3/5 (hip flexion, knee extension, ankle dorsiflexion) - Pronator drift: Left arm pronates and drifts downward when arms extended with eyes closed **Sensory Examination:** - Light touch: Decreased on left face, arm, and leg - Proprioception: Impaired in left fingers and toes - Pain/temperature: Decreased on left hemibody **Reflexes:** - Right biceps 2+, triceps 2+, brachioradialis 2+, patellar 2+, Achilles 2+ - Left biceps 3+, triceps 3+, brachioradialis 3+, patellar 4+ with clonus, Achilles 3+ - Babinski: Extensor response (upgoing toe) on LEFT; flexor (normal) on right - Hoffman's sign: Present on left **Coordination:** - Right: Normal finger-to-nose, normal heel-to-shin - Left: Unable to assess adequately due to weakness **Gait:** - Unable to walk independently; when supported, demonstrates circumduction of left leg (swings leg in arc due to stiffness) **Summary of UMN Findings:** - Weakness with spasticity (not flaccidity) - Hyperreflexia with clonus - Positive Babinski sign - Forehead-sparing facial weakness - NO atrophy, NO fasciculations **Diagnosis:** Right MCA territory stroke with left hemiparesis (UMN pattern) **Clinical Pearl:** Upper motor neuron lesions produce a characteristic pattern: weakness with increased tone (spasticity), hyperactive reflexes, and pathological reflexes (Babinski, Hoffmann). The weakness affects extensors more than flexors in the arm and flexors more than extensors in the leg. Forehead sparing in facial weakness indicates UMN localization because the upper face has bilateral cortical representation. The eyes "look toward the lesion" in acute cortical strokes. --- ## Case 2: Lower Motor Neuron Lesion (Guillain-Barre Syndrome) ### Patient Presentation **Demographics:** 34-year-old female **Chief Complaint:** Progressive weakness in legs and arms over 5 days **History of Present Illness:** The patient noticed tingling in her feet 8 days ago. Over the following days, she developed weakness in her legs, making it difficult to climb stairs. The weakness has ascended to involve her hips and is now affecting her arms. She had a respiratory infection with diarrhea 2 weeks before symptom onset. She feels short of breath when lying flat. **Systematic Neurological Examination:** **Mental Status:** - Fully alert and oriented; cognition intact **Cranial Nerves:** - II-VI: Intact - VII: Bilateral facial weakness - unable to fully close eyes, cannot puff cheeks or whistle; forehead also weak bilaterally (LMN pattern) - IX, X: Mild dysphagia; weak cough - XI-XII: Intact **Motor Examination:** - Inspection: No atrophy (too acute); no fasciculations - Tone: DECREASED throughout (flaccid); limbs feel "floppy" on passive movement - Strength (MRC scale): - Proximal upper extremities: 4/5 bilaterally (shoulder abduction, elbow flexion) - Distal upper extremities: 4+/5 bilaterally (wrist extension, grip) - Proximal lower extremities: 3/5 bilaterally (hip flexion, knee extension) - Distal lower extremities: 3/5 bilaterally (ankle dorsiflexion, plantarflexion) - Pattern: Symmetric, ascending weakness; proximal = distal **Sensory Examination:** - Light touch: Decreased in stocking distribution to mid-calf, glove distribution to wrists - Vibration: Decreased at toes, intact at ankles - Proprioception: Mildly impaired at toes bilaterally - Pain/temperature: Mild decrease distally **Reflexes:** - Biceps: ABSENT bilaterally (0) - Triceps: ABSENT bilaterally (0) - Brachioradialis: ABSENT bilaterally (0) - Patellar: ABSENT bilaterally (0) - Achilles: ABSENT bilaterally (0) - Babinski: ABSENT bilaterally (flexor/no response - toes stay still) **Coordination:** - Finger-to-nose: Intact but weak - Heel-to-shin: Unable to perform adequately due to weakness **Gait:** - Unable to stand without assistance - Steppage gait pattern when attempting to walk (high knee lift to clear floppy foot) **Respiratory Assessment:** - Forced vital capacity (FVC): 1.8 L (predicted 3.4 L) - 53% of predicted - Negative inspiratory force (NIF): -28 cm H2O (concerning if less than -30) **Summary of LMN Findings:** - Weakness with DECREASED tone (flaccidity) - ABSENT reflexes (areflexia) - NO Babinski sign - Facial weakness including forehead (LMN pattern bilaterally) - Sensory involvement in peripheral distribution **Workup:** - Lumbar puncture: Protein 185 mg/dL (elevated), WBC 3 (normal) - albuminocytologic dissociation - Nerve conduction studies: Prolonged distal latencies, conduction block, reduced amplitudes - demyelinating pattern **Diagnosis:** Guillain-Barre syndrome (acute inflammatory demyelinating polyradiculoneuropathy) **Treatment:** - ICU admission for respiratory monitoring - IVIG 0.4 g/kg/day for 5 days - Prophylactic DVT prevention - Pain management - Close monitoring of FVC and NIF (intubation if FVC <1L or NIF >-20) **Clinical Pearl:** LMN lesions produce the opposite pattern from UMN lesions: weakness with decreased tone (flaccidity), diminished or absent reflexes, and (over time) atrophy and fasciculations. In Guillain-Barre syndrome, the areflexia is often the most striking early finding. The ascending pattern and facial weakness are characteristic. Respiratory failure is the major life-threatening complication, requiring close monitoring of FVC. --- ## Case 3: Cerebellar Lesion (Cerebellar Stroke) ### Patient Presentation **Demographics:** 58-year-old male **Chief Complaint:** Sudden dizziness and inability to walk for 2 hours **History of Present Illness:** The patient was eating lunch when he suddenly felt the room was spinning. He vomited twice and noted that he could not walk straight, veering to the left. He has no arm or leg weakness. He has a history of atrial fibrillation (on anticoagulation) and hypertension. **Systematic Neurological Examination:** **Mental Status:** - Alert and oriented; cognition intact - Speech: Scanning dysarthria (staccato, irregular rhythm) **Cranial Nerves:** - II-V: Intact - VI: Nystagmus present - horizontal, gaze-evoked (worse on left lateral gaze), with rotatory component - VII-XII: Intact (no facial weakness, tongue midline) **Motor Examination:** - Tone: DECREASED on left (hypotonia is a cerebellar sign) - Strength: 5/5 in all extremities (NO weakness) **Sensory Examination:** - Completely normal throughout **Reflexes:** - 2+ and symmetric throughout; may be slightly decreased on left - Babinski: Absent bilaterally (flexor response) **Coordination (KEY FINDINGS):** - Finger-to-nose (RIGHT): Normal, accurate - Finger-to-nose (LEFT): Dysmetria (overshoots target), intention tremor (oscillation increasing as finger approaches target) - Heel-to-shin (RIGHT): Normal - Heel-to-shin (LEFT): Ataxic, irregular, falls off shin - Rapid alternating movements: Dysdiadochokinesia on LEFT (irregular rhythm and amplitude when tapping hand on thigh) - Rebound phenomenon: Present on left (arm overshoots when resistance suddenly released) **Romberg Test:** - Stands with feet together - unsteady with eyes OPEN - Still unsteady with eyes CLOSED (does not significantly worsen) - NEGATIVE Romberg (unsteadiness is not dependent on vision) - indicates cerebellar, not sensory, ataxia **Gait:** - Wide-based - Veers to the LEFT (toward the side of the lesion) - Cannot perform tandem walking - Unable to stand on left foot alone **Summary of Cerebellar Findings (DANISH mnemonic):** - Dysdiadochokinesia (left) - Ataxia (limb and gait) - Nystagmus (gaze-evoked) - Intention tremor (left) - Slurred/Scanning speech - Hypotonia (left) - ALL IPSILATERAL to the lesion (cerebellum exerts ipsilateral control) **Imaging:** - CT head: Hypodense region in left cerebellar hemisphere - MRI: Acute infarction in left PICA territory **Diagnosis:** Left cerebellar stroke (PICA territory) with ipsilateral cerebellar signs **Clinical Pearl:** Cerebellar lesions produce ipsilateral ataxia without weakness. The Romberg test helps distinguish cerebellar from sensory ataxia: in sensory ataxia, the patient is stable with eyes open but falls when eyes close (positive Romberg) because they lose visual compensation for proprioceptive loss. In cerebellar ataxia, the patient is unsteady regardless of eye opening. The cerebellar stroke patient has normal strength because pyramidal tracts are intact - coordination, not power, is the problem. --- ## Clinical Image ![Neurological examination techniques](case_01_image.jpg) **Image Description:** Illustration or photograph demonstrating key components of the neurological examination, including reflex testing with a reflex hammer, the Babinski sign test (stroking the lateral plantar surface), and pronator drift assessment with arms extended and eyes closed. These techniques help distinguish upper motor neuron from lower motor neuron pathology. **Attribution:** Image from Radiopaedia (https://radiopaedia.org/), Creative Commons Attribution-NonCommercial-ShareAlike 3.0 license.