Session 4: Neuromuscular Disorders

1. Session 4:Neuromuscular Disorders

2. Vignette • 19 yo athlete has "tingling" in arms & legs for the 3 days with nl strength and coordination. Exam in is normal. • Two days later, he is admitted with rapidly progressive weakness • Exam shows tachycardia, nl pupils, EOM, facial expression with a poor cough & gag. There is proximal weakness, areflexia and nl sensation. Bladder function is good as is rectal tone.

3. Questions • Which motor subsystem: muscle, neuromuscular junction, peripheral nerve, plexus, root, anterior horn cell, spinal cord, or brain is the problem located? • Differential diagnosis? • Tests • CSF findings • Management • Significance of the tachycardia and management • Prognosis • What if symptoms developed over 6 months?

4. Guillain-Barre Syndrome: Acute Inflammatory Demyelinating Polyneuropathy (AIDP) Georges Charles Guillain Jean-Alexandre Barre André Strohl Jean Landry

5. GBS • Causes: In about 80% of the patients, symptoms began about 5 days to 3 weeks after a mild infection, surgery, etc. Some have infection by Campylobacter jejuni • Treatment includes plasmapheresis (plasma exchange, PLEX) and/or high-dose immunoglobulin therapy.

6. Muscle NMJ Nerve ALS Cord Prox/distal P P D/P D/P D/P Sensory - - + - + Prom fascic - - + ++ - Reflexes - nc - + + EOM + + + - - Dysarth/dysph + + + + - Bladder - - + - +

7. ??? diab neurop CIDP CMT I CMT II Axonal vs Demyelin A or D A or D Sens vs. sensmotor Both Length-dep Yes

8. Muscle Tone: Hypotonia/Atonia: Reduce or absent tone; associated with LMN or cerebellar lesions or acute UMN insult (e.g., spinal shock) Increased tone Rigidity Present bidirectional – associated with basal ganglia/extrapyramidal lesions (when accompanied with tremor there is “cogwheeling”). Changes in tone may be accentuated with contralateral limb activation. Performed by passively moving appendicular or axial structures Spasticity Velocity dependent; unidirectional increase in tone; associated with UMN lesion Paratonia Also known as “gegenhalten”; which is apparent increase in tone due to patient’s inability to relax; often present in individuals with cognitive changes

9. Function Root Nerve Deltoid Sh ab C5 Axillary Biceps flex C5/6 Musculocutan Triceps ext C6 Radial Finger ext ext C7 Radial APB abd C8/T1 Median FDI abd C8/T1 Ulnar Iliopsoas Hip flex L12 Upper plexus Quadriceps Leg ext L234 Femoral Hamstrings Leg flex S1 Sciatic Tibialis ant Dorsi L45 Peroneal Gastroc Plantar S1 Tibial EHL Dorsi L5 Peroneal

12. Axillary Nerve

13. Median Nerve Musculocutaneous Nerve

14. Radial Nerve Ulnar Nerve

15. Nerve

16. Peroneal Nerve

17. Femoral Nerve

18. Obturator Nerve Tibial Nerve

19. Deltoid C5 Axillary N. 

20. Biceps C6 Musculocutaneous N. 

21. Triceps C7 Radial N. 

22. Brachioradialis C6 Radial N. 

23. Extensor Carpi Ulnaris C7 Radial (Posterior Interossious) 

24. Extensor Digitorum C7 Radial (Posterior Interossious) 

25. First Dorsal Interossious T1 Ulnar Nerve

26. Abductor Pollicis Brevis T1 Median N.

27. Psoas L1,2 

28. Hamstring S1 Sciatic 

29. Tibialis Anterior L4,5 Deep Peroneal N. 

30. Ext. Hallucis Longus L5 Deep Peroneal N.

31. Extensor Digitorum Brevis L5 Deep Peroneal N. 

32. Extensor Digitorum Longus L5 Deep Peroneal N. 

33. Gastrocnemious S1 Tibial N. 

34. Grading Strength 

35. Deep Tendon Reflexes : Adequate Relaxation Stretch Tendon Suddenly Reinforcement Grading 0 to 4

36. Deep Tendon Reflex Technique: Adequate Relaxation Stretch Tendon Suddenly Reinforcement Grading 0 to 4

37. Segmental Reflex Innervation:

38. Reinforcement

39. Grading 0 to 4

46. Abnormal Plantar Response: Extension of the great toe and fanning of other toes implies upper motor neuron dysfunction. Babinski

47. Chaddock

48. Oppenheim

49. Gordon

50. Snout