Nervus ulnaris

arises from the fasciculus medialis plexus brachialis (C8–Th1)
initially runs together with n. medianus and a. brachialis along the inner edge of the arm
stored medially from the artery
in the middle of the arm it passes through the septum intermusculare brachii mediale and runs to the back of the medial epicondyle of the humerus
in sulcus n. ulnaris placed superficially, covered by skin and arm of lig. collaterale mediale – it is fixed by it in the bone groove (due to its superficial position, it is easily vulnerable - tumulus)
more distally, it enters together with a. ulnaris between the two heads m. flexor carpi ulnaris and descends on the ventral side of the forearm, between the m. flexor carpi ulnaris and m . flexor digitorum profundus towards the palm
enters the palm above the retinaculum flexorum, radially from the os pisiforme
terminal branches' - ramus superficialis and ramus profundus

Branches on the forearm[edit | edit source]

Rami musculares - for m. flexor carpi ulnaris and for the ulnar half of m. flexor digitorum profundus (part of the muscle for the 4th and 5th fingers).
Ramus cutaneus palmaris
Ramus dorsalis n. ulnaris - departs in the distal third of the forearm, turns around the ulna to the dorsal side of the forearm, pierces the fascia, innervates: the skin of the ulnar half of the back of the hand and the skin 5th, 4th and ulnar halves of the 3rd finger (with the exception of the nail joint - innervated from the median nerve)
Ramus palmaris n. ulnaris - innervates the skin of the ulnar half of the carpal region and extends to the hypothenar and the palm

Ramus superficialis - runs along the hypothenar muscles, runs under and innervates m. palmaris brevis, the final branches innervate the skin of the ulnar part of the palm, the 5th finger and the ulnar half of the 4th. finger - n. digitalis palmaris communis IV and 3rd finger nn. digitales palmares proprii'
Ramus profundus - pierces the beginnings of the hypothenar muscles into the middle palmar space, it runs in an arc together with the arterial arcus palmaris profundus taken to the fascia interossea palmaris, branches for the hypothenar muscles, for mm. lumbricales (III. , IV.), for all mm. interossei, for m. adductor pollicis and for caput profundum m. flexoris pollicis brevis

PETROVICKÝ, Pavel. Anatomy with topographic and clinical applications. Osveta edition. 2002. 542 pp. ISBN 80-8063-048-8.