Dermatomes of upper limb

Question 1

Spinal segment C3, C4

Dermatome description

Answer 1

Region at base of neck extending laterally over shoulder

Question 2

Spinal segment C5

Dermatome description

Answer 2

Lateral aspect of arm (superior aspect of abducted arm)

Question 3

Spinal segment C6

Dermatome description

Answer 3

Lateral forearm and thumb

Question 4

Spinal segment C7

Dermatome description

Answer 4

Middle three fingers and centre of posterior aspect of forearm

Question 5

Spinal segment C8

Dermatome description

Answer 5

Little finger, medial side of hand and forearm (inferior aspect of abducted arm)

Question 6

Spinal segment T1

Dermatome description

Answer 6

Medial aspect of forearm and inferior arm

Question 7

Spinal segment T2

Dermatome description

Answer 7

Medial aspect of superior arm and skin of axilla

Question 8

Foerster versus Keegan and Garrett

Answer 8

Foerster (1933) Innervation of medial aspect of the limb by upper thoracic spinal cord (T1-3) - consistent with angina pectoris referred pain Keegan and Garrett (1948) Regular progression and correlation with developmental concepts