Ulnar neuropathy pearls

Most distal muscle of ulnar nerve is adductor pollicis reached at the first free web space between the thumb and forefinger. It adducts the thumb. Unlike abductor digiti minimi itmay be involved in lesions of Guyon's canal. Like ADM its involved in other ulnar entrapments (cubital tunnel, tardy ulnar palsy, cervical rib).

Klumpke's paralysis (avulsion of C8 T1 roots) will involve these plus abductor pollicis brevis (APB median C8 T1).

The FDI may occassionally get innervation from the median nerve / musculocutaneous nerve