Approach to Weakness PDF

NEW! Approach to Weakness Ap...

NEW! Approach to Weakness Approach to Credits: How to Bilateral Weakness Prof Umapathi’s many lectures decide on Tips (UL/LL) M3 Neuro STJ by CO2023 the path Many others General Inspection Assess Wasting, Tone, Reflexes, Clonus, Babinski UMN: LMN: 1. Wasting minimal 1. Wasting +++ 2. Hypertonia 2. Flaccid Tone UMN UMN or LMN? 3. Hyporeflexia LMN 3. Hyperreflexia 4. Babinski +ve 4. Babinski -ve 5. Clonus +ve 5. Clonus -ve Sensory assessment: 1. It is CRUCIAL to be certain whether sensation is normal/abnormal 2. Use the different modalities (fine touch, pain, vibration, proprioception), use as many as you need to be confident! Unilateral or 3. Use a sensory examination spiel (to prime patient to give you findings) Unilateral Bilateral LL Bilateral? I would like to test your sensation in your hands/feet. I would like to find out in which parts you are feeling less/feeling numb. As I test, please tell me which Proximal Proximal or parts are feeling less, different or simply feel abnormal Distal Weakness First, I am using this tuning fork... Weakness Distal? I am using this soft cotton wool/tissue I am using this sharpened toothpick Contralateral Contralateral No = Brain Pain + Temp Spinal Cord Tracts: Sensation Sensation Sensory loss Sensation Intact Deficit 1. Spinothalamic: Anterolateral Abnormal intact? Sensory assessment technique: Pain + Temp 1. Vibration - with tuning fork (start with this cos its very objective and accurate, then D: level of spinal cord cont with the following to see pattern) Strike at hand Place on base of toe (can feel 2. Corticospinal: Lateral 80% for a median of ard 8 seconds) Motor (pyramidal) 2. Light touch (up to knee) - use a rolled up piece of tissue Brown Sequard D: Medulla (brainstem) Spinal Cord 3. Pin prick (up to mid calf) - use a toothpick or satay stick (hold loosely and allow it Cortical Syndrome to slip in your hand) Percussion & Grip Distal Myopathy Cortical Signs: Cortical 3. DCML: Posterior signs? 4. Proprioception (position sense) Myotonia (Myotonic Dystrophy) Vibration, fine touch, proprioception MND Brain 5. Temperature - use alcohol swab (feel coldness, see if they feel the coldness more HSP Brown Sequard: (ALS, PLS) at some parts) D: Medulla (brainstem) 1. Contralateral Spinothalamic Central Cord 2. Ipsilateral Corticospinal Fasciculations: Sensation Sensation Zebra AHC/MND D: decussates at Syndrome 1. Tongue (just ask them to open their mouth, Pain/Fine touch: Sensation Intact Fasciculations 3. Ipsilateral DCML protruding tongue may affect) Abnormal intact? Stripes? (ALS, PMA, Polio) ASIA Scoring is sufficient (Dermatomal) - as you 2. Major muscle bulk (flick to elicit) Clumsy Hand Cranial simply need to know whether sensation is intact or Sensation Sensation Brainstem affected Sensation Intact Syndrome: Nerve Palsy? Central Cord: Abnormal intact? 1. Cape-like Bilateral weakness if sensation affected, test more sites to check if its (UL>LL) gloves & stocking vs patchy distribution Pure Motor Peripheral Neither Neuropathy 2. Loss of Spinothalamic Cortical Subcortical (MMN) MUD: Motor>>sensory deficit (Parasaggital (Binswanger / Subcortical UL>>LL (cape-like) lesion) multiple lesions) Distal>>proximal deficit Guillain-Barré Syndrome (GBS) Onset: Acute Glove & Stocking Sensory loss Patchy ***Spares of DCML Mx: IVIG only Demyelinating Distribution Distribution Distribution Anterior Cord Fatigability: Fasciculations: Chronic Inflammatory Demyelinating Syndrome (CIDP) Polyneuropathy 1. Fatigable Ptosis (ask patient to look Zebra 1. Tongue (just ask them to open their mouth, Syndrome Fatigability Fasciculations Onset: Chronic (GBS/CIDP) laterally) Stripes? protruding tongue may affect) Mx: IVIG + Steroids 2. Diplopia on prolonged upward looking 2. Major muscle bulk (Expose as much as Glove & Stocking Distribution: 3. Curtain-sign (ptosis worsened when you possible, flick to elicit) 1. All 4 limbs affected Both help lift up non-ptosis eye) 2. LL>UL (Stockings>Gloves) Anterior Cord: early loss of reflexes 4. Ice-pack test (ptosis relieved with ice-pack 3. Symmetrical placed on eyes till discomfort) 1. Bilateral Spinothalamic Loss proximal and/or distal weakness 5. Tensilon test (Edrophonium injection) NMJ AHC/MND Ulnar C8 Why is neck flexion/extension (Myasthenia (SMA, PMA, ALS, neuropathy Radiculopathy assessed in GBS? Why eyes are assessed for Neither It is a good surrogate measure for fatigability? Gravis, LEMS) Polio) Amyotrophic Lateral Sclerosis diaphragm involvement as both are It is more specific compared to other (ALS) is the commonest MND Posterior Cord innervated by same nerve muscles such as arm muscles which (>90%) Syndrome fatigue even in healthy people Fasciculations are not specific to MND, it is just Radial a LMN sign; but marked fasciculations most Peripheral Neuropathy EOM, speech muscles, lung muscles likely to be MND are typically non-fatigable Neuropathy Also note that tongue fasciculations suggest (ABCDEFGH) “ulnar” distribution Posterior Cord: Proximal bulbar involvement 1. Bilateral DCML Loss Myopathy “Wrist drop” (NDICE) C7 Radiculopathy Peripheral Neuropathy Etiologies A: Alcohol B: B12 Deficiency Neoplastic Drugs Inflammatory Congenital C: CMT (Charcot Marie Tooth) General Approach to 1 limb distal weakness: Only 1 limb (Dermatomyosit (Colchicine, (Dermatomyosit (Duchenne’s/Be Endocrine D: Diabetes Radiculopathy UL or LL? affected? Mononeuropathy (e.g. ulnar) is) Statins, fibrates, is, Polymyositis) cker’s, MD, (Hyper/Hypothy E: Endocrine (Hypothyroidism) F: Facioscapulohumeral muscular dystrophy (FSHMD) Femoral Steroids) FSHMD) roid, Cushing’s, G: GBS (Guillain-barré syndrome) Vit D defici.) neuropathy *Diabetic neuropathy will have markedly Dermatomyositis Zebra Stripes: Myotonia Dystrophy (MD) Zebra Stripes: Hyper/Hypothyroidism Zebra Stripes: sensory>motor deficits! For motor to affect patient, dx 1. Heliotrope rash (violaceous/PURPLE rash; non- photosensitive/around the eyes) 1. Percussion Myotonia (hand involuntarily flexes on percussion/tapping of thenar) 1. Thyroid Eye Disease (specific to Grave’s Dx) 2. Clubbing (Thyroid Acropachy) must be very severe; need to correlate with extent of knee weakness diabetic retinopathy which has similar progression 2. Shawl + V-neck rash (photosensitive neck rash) 2. Grip Myotonia (patient is unable to relax/open 3. Essential Tremors Footdrop 3. Gottron’s plaque (purplish plaques on knuckles his hand quickly after you ask him to clench his & other finger joints) fists tightly) Peripheral Neuropathy Zebra Stripes: 4. Subungal erythema Alcohol (parotidomegaly, dupuytren's contracture) 5. Nail-fold infarcts 1. Cushing’s Zebra Stripes: Purple striae B12 (anaemia) L4 6. Gottron’s sign (purplish plaques on extensor FacioScapuloHumeral Muscular Dystrophy 2. Moon facies (facial fullness) CMT (Pes Cavus, Hammertoes, inverted champagne Mononeuritis Radiculopathy surface of elbows) (FSHMD) Zebra Stripes: 3. Buffalo hump (supraclavicular fatpads) bottle (severe wasting)) Multiplex 1. Facial weakness 4. Hirsutism (male-pattern hair growth) DM (diabetic dermopathy, hypocount pinprick) 2. Scapular winging (+curious scapula) 5. Acne, thin skin Hypothyroidism (delayed reflexes, goitre) Dermatomyositis Etiologies 3. Biceps+Triceps weakness (preserved deltoid) FSHMD (Curious Scapula, Beevor’s Sign, Biceps/Triceps weakness with preserved deltoids) 2" to Malignancy 4. Beevor sign (upward movement of umbilicus) 2" to Autoimmune condition GBS (marked lack of wasting as acute) L5 Peroneal Sciatic (Sjogren’s, SLE, Scleroderma etc) Radiculopathy neuropathy neuropathy Primary (polymyositis) Becker’s/Duchenne’s Zebra Stripes: 1. Calf Hypertrophy Leprosy Vasculitis *Majority of adult dermatomyositis is 2" malignancy Leprosy Zebra Stripes: Vasculitis Zebra Stripes: 1. Thickened Nerves (sural, superficial peroneal, 1. Hyperpigmented/purpuric painful rashes (of greater auricular nerve, superficial ulnar) varying ages) 2. Hypopigmented anesthetic rash 3. Neuropathic Charcot’s joints 4. Asymmetric anesthetic mutilating injuries Vasculitis Etiologies Systemic Vasculitis: PAN, Churg- Sites of Thickened Nerves: Strauss vasculitis, Wegener’s, Sural: thickened cord-like structure Cryoglobulinaemia behind the lateral malleolus Systemic immune dx: SLE, Sjogrens Superficial peroneal: visible/palpable Infections: Hep B/C, HIV cord anterior of lateral malleolus Greater auricular: visible cord from ear lobe to trapezius