Back Pain. John W. Engstrom, MD December 15, Disclosures. Neurology Clinical Dilemmas Goals. Neurology Clinical Dilemmas Goals

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1 Disclosures Nothing to declare --- or --- Significant ownership interests Consulting, speaker bureaus, honorarium, grants Link to Harrison s Chapter on Headache: on/education.html Clinical Neurology Dilemmas for the Primary Care Provider John Engstrom, MD April 27, 2012 Neurology Clinical Dilemmas Goals Know how to recognize common gait disorders-demonstration Hemiparetic gait Cerebellar gait Parkinsonian gait Steppage gait Sensory ataxia Elaborated gait Spastic parapetic gait Antalgic gait Neurology Clinical Dilemmas Goals Know signif of common sympt/sign patterns Central vs. peripheral weakness Tingling hand-positive vs. negative sensory symptoms Diminished sensation-patch vs. circumferential Testing attention vs. memory Altered vision on one side Facial palsy

2 Hemiparetic gait Arm held in flexion across the body Ipsilateral leg extended, foot drop +/- Leg extended during walking and foot circumducts The affected leg moves more slowly Easily recognized, occasionally confused with severe dystonia Cerebellar Gait Walking is relatively normal speed and accuracy, but the legs are unusually far apart (wide-based) Difficulty with tandem gait Limb coordination ataxic if the problem is pancerebellar, normal if only midline When very severe cannot walk, pitches about while sitting unless holding on with hands Common with chronic alcohol use Parkinsonian Gait Slow shuffling gait with stooped posture En bloc turning-many steps to turn Lack of associative movements-decr arm swing Bradykinesia-slows adaptive responses to sudden changes in postures-frequent falls and fractures Retropulsion-tendency to fall backwards Gait apraxia-get stuck in doorways or at curbs Ddx-all parkinsonian syndromes, not just PD Steppage Gait Underlying problem is a foot drop while walking The apparent excess hip flexion of the leg is compensation to avoid tripping over the foot Visible and embarassing; frequent falls/fractures AFO if foot dorflexion power less than antigravity Fits inside socks, shoes, pant Can be custom-made if necessary

3 Spastic Paraparesis (Scissors) Gait May only affect the legs if cord injury or arms and legs if brain injury When walking, both legs extend and circumduct Each leg completes its slow movement before the other initiates movement When affects legs alone, easily confused with severe dystonia-detailed neuro exam needed Sensory Ataxia (Wide-Based Stomping Gait) Seen in patients with severe sensory loss in feet Balance normally depends upon sensation from the feet, vestibular system, and vision Compensate by setting the legs far apart while standing and pounding the feet when walking to increase sensory input from the joints High risk falling in dark; flashlight on key chain Elaborated Gait Patient frequently pitches about during the testing of tandem gait, but does not fall If there is falling, the side is often inconsistent When analyzing the gait, the patient may unknowingly demonstrate exquisite balance Usually an indicator of a behavioral component to the symptoms; may still have abnl neuro exam Antalgic Gait Patient avoids full weight bearing on the affected limb by shifting weight to the unaffected side The affected limb moves faster when walking to lessen the time of weight bearing Common in patients with limb pain due to arthritis (e.g.-knee or hip joint pathology)

4 Q1: 60 yo man with HTN/DM has new foot drop. What neuro exam feature would not suggest an injury to the CNS? A) Hyper reflexia on the opposite side B) Slowed fast finger movements on same side C) Pronator drift on the same side D) Babinski sign on the same side E) Increased tone on the same side The Weak Patient: Central Weakness I Power - distal > proximal in limbs extensors > flexors in arms dorsiflexors > plantar flexors in legs lower 2/3 of face (if from brain injury) Bulk - Normal Tone - spastic; Babinski sign(s) present Reflexes - The Weak Patient: Central Weakness II Spasticity-velocity-dependent increase in tone to passive stretch of a limb that is greatest in the flexors of the arms and extensors of the legs -Rapid, repetitive movements are slow in the fingers and feet; dominant side normally faster -Pronator drift-pronation the essential finding; may also flex the fingers and drop the arm

5 CNS Weakness-Practical Implications Dictates whether or not CNS imaging likely to identify etiology Correlate with known history (e.g.-old stroke) If not CNS, there may be a PNS injury Consider EMG study Consider neurology consultation Q2: 30 yo woman notes intermittent tingling of the hands. Which of the following is not true? A) Tingling could be carpal tunnel syndrome B) Tingling could be hyperventilation syndrome C) Tingling could be C6 radiculopathy D) Tingling reflects a loss of sensory function E) You may never explain the tingling hands Sensory Symptoms-Positive and Negative Establish presence/absence sensory loss by exam! Numbness (negative sensory symptom) may indicate decrease in sensory function Paresthesias/pain (positive sensory symptoms) reflect alive nerve cells firing inappropriately May be neurologic (e.g.-nerve injury with deficits) May be non-neurologic (e.g.-fractured arm) Positive sensory symptoms often non-diagnostic! Q3: 35 yo woman has right hand/distal forearm circumferentially diminished light touch (2/10). Which answer is true? A) Exam finding could be due to carpal tunnel B) Exam finding could be due to cervical root C) Exam finding could be due to brain lesion D) Exam fining could be an ulnar neuropathy

6 Arm-Nerve Root Dermatomes Dermatomes-Hand Sensory Nerves Sensory Loss on Exam-Significance Sensory loss in a patch on a limb is due to nerve or nerve root injury Circumferential sensory loss in a limb-cns origin If PNS injury affected entire hand, would need to involve at least 3 nerve roots or 3 nerves Examine same side of the body for sensory loss in the face or leg Q4: 70 yo woman is described as forgetful. Digit span is 4 forward. Which statement is false? A) Result abnormal-indicates reduced attention B) The result may indicate delerium C) Association with fever, tachycardia, postural tremor, asterixis, or myoclonus favors delerium D) Memory testing next will be helpful E) Reviewing medications being taken is likely to be helpful.

7 Delerium Precludes Memory Testing Delerium fluctuating levels of consciousness and inattentiveness Nl digit span 7 forward, usu not culturally biased unless primary language not English Imm recall poor-can t test short-term memory Common gen exam accompaniments: fever, tachycardia, tremor, asterixis, myoclonus Neurologic exam: poor, fluctuating attention Delerium- Common Causes and Evaluation Metabolic Causes Hyponatremia, hypernatremia Renal failure Hypoxia, ischemia Hypoglycemia, hyperglycemia Hypothyroidism, hyperthyroidism Recreational drugs Alcohol intoxication / withdrawal Other drugs Hypercalcemia, hypermagnesia Hyperphosphatemia Laboratory Studies Na BUN, Cr PO2 Glucose Thyroid function tests Toxicology screen Alcohol level, osmolarity Review medications Calcium, magnesium Phosphate Delerium Common Causes and Evaluation Infectious Causes Sepsis Meningitis Neurologic Causes Subarachnoid hemorrhage Cerebral infarction Seizures, post-ictal state Laboratory Studies Cultures, CBC, Chest X-Ray, UA Lumbar puncture (LP), Cultures, CBC Brain CT, LP Brain CT or MRI Consider brain CT/MRI, EEG Q5: A 35 yo woman sts she cannot see to the right. Which statement is false? A) She could have impaired right eye vision B) She could have impaired left eye vision C) Visual field testing should be done D) She could be neglecting vision to the right E) She could have a scotoma

8 Visual Field Testing Test each eye separately-have pt cover one eye Imagine a circle representing the 4 visual quadrants; place your finger in the center of each Move the finger and ask the patient if they see it The left brain is wired to the right field of vision and the right brain to the left field of vision Neglect-patient knows she can t see to right and is therefore not neglecting the right Q6: 38 yo woman-new left lower facial weakness. Which statement is false? A) The weakness indicates an upper motor neuron (CNS) facial paralysis B) The injury could be in the brainstem C) The injury could be in the brain D) It will be difficult to use the exam to tell if the nerve tissue injury is in the CNS or PNS E) Finding could represent post-sz weakness Facial Palsy Lower 2/3 of face (smile and eye closure) indicates upper motor neuron (CNS) weakness Entire face (including furrowing of the brow) indicates LMN (PNS) weakness Ask pt to smile, close eyes forcefully, raise brow Easy to distinguish If CNS-get brain imaging; if PNS-full neuro exam Facial paresis can be a post-ictal finding, resolves

9 Q7: 38 yo man-new complete left facial weakness. Which statement is false? A) The injury could be in the subarachnoid space B) The injury could be in the brainstem C) Injury could along course of the facial nerve D) Injury could be after the nerve exits the parotid gland E) Injury could be first attack of multiple sclerosis Facial Nerve-Long Brainstem Course How to approach any cranial nerve palsy 3 compartments-brainstem, subarachnoid space (SAS), and peripheral nerve Brainstem-usu CNS/cranial nerve (CN) exam abnl SAS-other CN or nerve root findings; (e.g.-absent DTRs); neoplastic/infectious meningitis? Peripheral Nerve-Can follow expected course on brain MRI; only nerve branches if too distal

10 Bell s Palsy-A Cautionary Tale Most lower motor neuron facial pareses will be Bell s palsy Leave yourself wiggle room-patient to return if there are new symptoms or worsens further Other causes of LMN facial-ms, brainstem glioma, Lyme meningitis, metastatic meningeal neoplasm, parotid tumors, sarcoid Other CN involved? Only distal nerve twigs? Bilateral Bell s Palsy? Variations: The Bronx Facial Palsy A benign variant Q9: 38 yo man with dx Bell s palsy returns after 1 year with partial ipsilateral eye closure when smiling. Which statement is true? A) He probably has synkinesis B) He has post-bell s myoclonus C) He should stop smiling D) He will not have partial eye closure with facial grimacing

11 Synkinesis 50 yo man tingling of R hand, diminished lt touch over palmar D1 and D2. Which statement is false? A) Patients can confuse a difference in quality of sensation with a decrease in sensation (numbness) B) Sensation should be compared with a normal control patch of skin in the opposite limb C) If pt reports 8/10 lt touch on R hand and 10/10 on left, the loss of function is definite D) Give up-the sensory exam is impossible Practical Tips for the Sensory Exam Ask pt when simul comparing numb patch with a nl analagous patch in opposite limb if difference is in quantity of touch or quality of sensation Given the nl side 10/10 and 0 = no sensation 5/10 is half nl side What is abnl side x/10? Sometimes pt can t tell; a limit of the sensory exam Pseudoquantitative; if < 5/10-probable sensory loss Clinical Dilemmas in Neurology Know your gaits! Distinguish UMN from LMN weakness Positive sensory symptoms indicate presence of nerve function, diminished sensation by exam indicates loss of nerve function Digit span-a great screen for attn; if abnormal don t test recent memory or complex cognition

12 Clinical Dilemmas in Neurology Visual fields are easily screened in patients with directional visual loss or symptoms Distinguish UMN facial from LMN facial When Bell s palsy might not be a Bell s palsy How to use the normal side as a control during the sensory exam