T1 nerve root

Roots · T1

The lowest root. Joins C8 to form the lower trunk, and carries the sympathetic fibres whose interruption produces Horner syndrome.

Detail

Motor
Contributes to the intrinsic muscles of the hand
Sensory
Medial arm (T1 dermatome)

When it goes wrong

Pancoast tumour, or a cervical rib compressing the lower trunk

Wasting of the small muscles of the hand with medial arm numbness, and Horner syndrome if the sympathetic fibres are involved.

Practise this structure

No question in the bank is tagged to T1 nerve root yet. Questions appear here automatically once one is — the question bank is free to browse in the meantime.