- axillary nerve (C5
) originates from and passes backward from posterior cord
of brachial plexus
- at level of axilla;
- it arises immediately posterior to the coracoid process and conjoined tendon;
- it crosses the inferolateral surface of the subscapularis
, 3-5 mm medial to the musculotendinous border;
- sweeping a finger from superior to inferior along the anterior aspect of subscapularis will catch the axillary nerve;
- it courses along inferior border of the shoulder capsule, & then thru quadrangular space
below lower border of teres minor
where it passes around posterior and lateral humerus on deep surface of the deltoid
- after passing thru quadrilateral space (at inferior border of subscapularis muscle and posterior aspect of the humeral neck) it divides into
anterior and posterior trunks;
- anterior trunk:
- branches supply the middle and anterior deltoid as it winds around the inner surface of deltoid;
- posterior trunk:
- branch to the teres minor
- posterior part of the deltoid muscle
(lie deep in deltoid);
- terminal branches: superior lateral brachial cutaneous nerve
- The Posterior Branch of the Axillary Nerve: An Anatomic Study.
- Anatomical basis of the variable aspects of injuries of the axillary nerve (excluding the terminal branches in the deltoid muscle).
- The position of the axillary nerve in the deltoid muscle. A cadaveric study.
- Anterior Dislocation of Shoulder:
- because of its relatively fixed position at posterior cord
and at deltoid
, any downward subluxation of proximal humerus can result in traction
and injury to the nerve;
- also because of its close relationship to the inferior capsule makes it suseptible to injury with anterior dislocations;
- in pts w/ axillary nerve injuries following anterior dislocation, sensory exam over the lateral shoulder will be normal;
- injury causes loss of shoulder abduction & external rotation;
- Axillary Nerve and Shoulder Reconstruction:
- Anatomy of the axillary nerve and its relation to inferior capsular shift
- The axillary nerve and its relationship to common sports medicine shoulder procedures.
- Prevention of Axillary Nerve Injury in Anterior Shoulder Reconstructions. Use of a Subscapularis Muscle-Splitting Technique and a Review of the Literature.
- The Anatomic Relationship of the Brachial Plexus and Axillary Artery to the Glenoid. Implications for Anterior Shoulder Surgery.
- The Relationship of the Axillary Nerve to Arthroscopically Placed Capsulolabral Sutures. An Anatomic Study.
- Determining the Relationship of the Axillary Nerve to the Shoulder Joint Capsule from an Arthroscopic Perspective.
- Axillary Nerve Injury during Rotator Cuff Surgery:
- if deltoid
is split anteriorly for > 5 cm, branches of axillary nerve will be damaged, rendering corresponding portion of deltoid ineffective;
- in smaller patients, the deltoid should not be split more than 4 cm;
- smallest split possible should be made in deltoid to permit sufficient exposure of the rotator cuff
- arm can be passively moved into various positions to allow this exposure without creating a larger muscle split than is necessary;
- Axillary Nerve and Proximal Interlocking Screws for IM Nailing:
(see IM nailing
- Relationship of the axillary nerve to the proximal screws of a flexible humeral nail system: an anatomic study.
- Antegrade locked nailing for humeral shaft fractures.
- Percutaneous Pinning of the Proximal Part of the Humerus. An Anatomic Study.
- Anatomic considerations of locked humeral nailing.
The sub-deltoid approach to the metaphyseal region of the humerus
Repair of isolated axillary nerve lesions after infraclavicular brachial plexus injuries: case reports
Suprascapular neuropathy in the differential diagnosis of rotator cuff injuries
Isolated and combined lesions of the axillary nerve. A review of 146 cases
Surgical anatomy of the axillary nerve
Is There a Safe Area for the Axillary Nerve in the Deltoid Muscle?
The anatomic relationships of the axillary nerve and surgical landmarks for its localization from the anterior aspect of the shoulder.
Original Text by Clifford R. Wheeless, III, MD.