Because T1 carries the sympathetic fibers for the eye, injury to this nerve can result in Horner’s Syndrome. This is often seen in Pancoast tumors (lung cancer located at the apex of the lung) that invade the T1 nerve root.
It provides sensation to the medial (inner) aspect of the forearm and the upper arm near the elbow. t1 nerve
: It innervates several intrinsic hand muscles, including the abductor pollicis brevis (used for thumb movement), interossei (used to spread fingers), and lumbricals. Because T1 carries the sympathetic fibers for the
T1 carries sympathetic fibers that can affect the eye and face; damage here can sometimes lead to Horner’s syndrome , characterized by a drooping eyelid and constricted pupil. Clinical Findings in T1 Pathology interossei (used to spread fingers)