Approach to Weakness

Question 1

pattern of weakness in Primary Muscle disorders

Answer 1

Proximal mm and symmetric

- neck flexors and extensors (not affected in nerve or brain lesions) may be weak

Question 2

signs and sx of primary muscle disorder

Answer 2

• may have muscle pain
• no sensory findings
• reflexes perserved

Question 3

pattern of weakness in NMJ disorders

Answer 3

• mostly proximal mm
• ptosis and weakness of EOM, bulbar and neck mm
• usually show fatigability
• no sensory sx

Question 4

mononeuropathies MC occur as a result of..

Answer 4

entrapment

Question 5

mononeuropathy multiplex is usually due to…

Answer 5

systemic vasculitis
metabolic
rheumatologic dz

Question 6

pattern of weakness in nerve root disorders

Answer 6

weakness in the muscles inn. by fibers from that root, while leaving other neighbouring muscles unaffected

Question 7

radiculopathies are often assoc with

Answer 7

tingling and pain - radiating out from neck or back

Question 8

if multiple muscles in a limb are weak and do not conform to a pattern of particular nerve root or nerve, what should you suspect

Answer 8

plexus problem

Question 9

causes of plexopathies

Answer 9

idiopathic inflammation, radiation, metastases, hemorrhage or trauma

Question 10

two patterns of weakness in spinal cord

Answer 10

1. ant. horn cells - mimics radiculopathy

2. weakness below level of lesion due to interruption of corticospinal tracts (UMN signs)

Question 11

pattern of weakness in lesion of cerebral hemisphere

Answer 11

UMN pattern in contralateral body part

- region depends on what part of homunculus is disturbed

Question 12

lesions in base of pons (weakness)

Answer 12

weakness of IL face and CL arm and leg (Crossed signs)