MSK

Question 1

Dermatomes upper limb (anterior)

Answer 1

Question 2

Dermatomes upper limb (posterior)

Answer 2

Question 3

Dermatomes Lower Limb

Answer 3

Question 4

Dermatomes Trunk

Answer 4

Question 5

Myotomes Upper Limb

Answer 5

Neck Flexion - C1,2

Lateral neck flexion - C3

Shoulder shrugging - C4

Shoulder Abduction - C5,6 (axillary)

Elbow Flexion - C5,6 (muskulocutaneous)

Elbow Extension - C6,7,8 (radial)

Wrist Extension - C7,8 (radial)

Finger Extension - C7 (radial - posterior interosseous)

Finger Flexion - C8 (median)

Finger Abduction - C8, T1 (ulnar)

Abductor pollis brevis - T1 (median)

Question 6

Myotomes Lower Limb

Answer 6

Hip Flexion - L2,3 (femoral)

Hip Extension - L4,5 (inferior gluteal)

Knee Extension - L3,4 (femoral)

Knee flexion - L5,S1

Ankle Dorsiflexion - L4,5 (deep peroneal)

Great toe extension - L5

Ankle Plantarflexion - S1,2 (tibial)

Question 7

Reflexes

Answer 7

Biceps & Brachioradialis - C56

Triceps - C78

Patellar - L34

Achilles - S12

Question 8

Spurling’s Sign

Answer 8

• pain down arm with axial load to head in extension and lateral flexion towards affected side
• 90% specific, 45% sensitive for radiculopathy

Question 9

L’hermitte’s Sign

Answer 9

• electric shock pain/paresthesias down spine into arms with forward neck flexion

Question 10

Atraumatic Neck Pain - Indications for Imaging

Answer 10

• acute, atraumatic, nonradicular/nonmyelopathic
  
  • no imaging
• chronic (weeks-months) or RA/ankspond –> c-spine films
  
  • bone/disc margin destruction/instability –> MRI
• neuro ssx –> MRI (inpatient if progressive weakness or ssx myelopathy)
  
  • CT myelogram if cannot do MRI

Question 11

DDx of Atraumatic Neck Pain

Answer 11

• cervical disc herniation
  
  • worse valsalva
  • +ve Spurling’s
  • better with manual cervical distraction in flexion
  • most common c5-c6, c6-c7
  • MRI
• cervical spondylosis & stenosis
  
  • may cause myelopathy with osteophytes
• cancer
  
  • MRI entire spine
• cervical myofascial pain syndrome
• epidural abscess
• osteomyelitis
• discitis
  
  • night pain, constant
• spinal epidural abscess
• transverse myelitis
  
  • MRI may lag behind findings
  • admit if suspicious even if MRI neg
  • LP lymphocytosis + protein
  • treat steroids + plasma exchange
• cervical spinal epidural hematoma
  
  • patient on OAC/hemophilia

Question 12

Treatment/Dispo of Atraumatic Neck Pain

Answer 12

• radiculopathy
  
  • NSAIDS, opioids, GP f/u for imaging
  • admit if
    
    • progressive weakness
    • acute/progressive symptoms
    • signs of myelopathy
• myelopathy
  
  • bilat symptoms, sexual dysfunction, bowel/bladder/clumsiness in hands
  • d/w neurosx