Set pattern and Neurology Algorithms

Question 1

General set pattern

Answer 1

1. Distinguishing UMN vs LMN and its chronicity
   - UMN: spastic (hypertonia), hyperflexia, contractures
   - LMN: flaccid (hypotonia), hyporeflexia, wasting
2. Pattern and geographical distribution
   - Symmetry vs asymmetry
   - Focal, monoparesis, hemiparesis, paraparesis, tetraparesis
3. Site of involvement
   - Left or right or both
   - Proximal vs distal
   - UL or LL or both
   - Facial involvement
4. Motor and sensation involvement
   - Pure motor vs pure sensory vs mixed
   - Think: UMN (cortex) -> LMN (anterior horn -> root -> plexus -> nerves -> NMJ -> muscles)
   - Think of radiculopathy - overlapping dermatomes with less sensation impairment
5. Functional status and cognition

Question 2

Levels of lesions

Answer 2

UMN
Cortical and subcortical
Spinal cord

LMN
Anterior horn
Roots and plexus
Peripheral nerves
NMJ
Muscles

Question 3

List of diseases corresponding to levels

Answer 3

Cortical and subcortical
1. Cortex and subcortical injuries (strokes, haemorrhage)
2. Brainstem lesion
3. Multiple sclerosis

Spinal cord
A. Whole cord lesion
1. Cauda equina or conus medullaris syndrome
2. Transverse cord lesion
3. Spondylosis and myelopathy - disc hernia, OA, tumour compression
4. Multiple sclerosis with transverse myelitis

B. Focal cord lesion
5. Subacute combined degeneration
6. Tabes dorsalis
7. Posterior spinal artery occlusion
8. Syringomyelia

C. Spastic paraparesis plus syndrome
9. Friedreich’s ataxia
10. Spinocerebellar ataxia
11. Hereditary spastic paraparesis

Anterior horn
1. Motor neuron disease - ALS, SMA (proximal > distal)
2. Poliomyelitis (proximal > distal)
3. Hirayama disease (distal > proximal)

Roots, plexus
1. Infectious nerve root - TB, Lyme, syphilis, shingles
2. Radiculopathies - physical compression, tumour, OA, etc

Peripheral nerves (predominantly distal)
A. Polyneuropathies
1. Multifocal motor neuropathy
2. GBS (AIDP) and CIDP
3. HSMN / CMT or AMAN

B. Mononeuropathies
4. Peripheral neuropathies - median, ulnar, radial, etc
5. Mononeuritis multiplex

NMJ
1. Myasthenia gravis
2. Lambert Eaton syndrome
3. Botulism

Musculopathy
A. Proximal
1. FSHD
2. Inclusion body myositis
3. Polymyositis or dermatomyositis
4. Duchenne’s and Becker’s
5. Endocrine - Cushing’s, steroidal, acromegaly, thyroid
6. Chronic alcoholism or drugs

B. Distal
7. Myotonic dystrophy

Question 4

Geographical pattern of weakness and etiologies

Question 5

Lower motor weakness algorithm

Answer 5

Question 6

Upper motor weakness algorithm

Answer 6

Question 7

Ptosis algorithm

Answer 7

1. Unilateral or bilateral?
2. Partial or complete ptosis?
3. Fatigability
4. Pupil function
5. Extraocular motility

Question 8

Foot drop algorithm

Question 9

Horner’s syndrome algorithm

Answer 9

First order - from brainstem to C8/T1
- Symptoms: ptosis, miosis, anhidrosis of face and arm
- Causes: brainstem disorder, hypothalamic disorder, cervical cord disorder
> Stroke > Tumour > MS (demyelination) > myelitis > syringomyelia

Second order - until lung, including cervical rib
- Symptoms: ptosis, miosis, anhidrosis of face only
- Causes: C8/T1 radiculopathy, brachial plexus, vascular abnormalities
> trauma > inflammation > pancoast tumour > carotid disease (aneurysm, dissection)

Third order - until superior cervical ganglion, splits and follows ECA and ICA
- Symptoms: ptosis, miosis, NO anhidrosis
- Causes: superior cervical ganglion disorder, ICA disorder, CSS/SOF/OA disorder
> trauma > ICA aneurysm/dissection > pituitary tumour > inflamamtion > CS thrombosis

Question 10

Upper limb algorithm