1. Dana Brandariz, Brittany Clark and Ryan Collins
Brachial Plexus
Dana Brandariz, Brittany Clark and Ryan Collins

2. What is the Brachial Plexus?
Anterior roots, C5-T1
Cervical region extending to axilla
5 sections
Roots
Trunks
Divisions
Cords
Terminal Branches
Roots: Anterior Rami of the C5-T1 nerves
-usually pass through the gap between the anterior and middle scalene muscles with the Subclavian Artery
Trunks: roots of the brachial plexus unite to form three trunks
-superior trunk: C5 and C6 roots
-middle trunk: C7 root
-inferior trunk: C8 and T1 roots
-Each trunk then divides into anterior and posterior divisions as the plexus passes through the cervico-axillary canal (posterior to the clavicle)
-anterior divisions supply the anterior compartments of the upper limb (flexors)
-posterior divisions of the trunks supply the posterior compartments of the upper limb (extensors)
-the divisions of the trunks form 3 cords within the axilla
-anterior divisions of the superior and middle trunks unite to form the lateral cord
-anterior division of the inferior trunk continues as the medial cord
-posterior divisions of ALL 3 trunks form the posterior cord
-the cords are named for their position in relation to the second part of the axillary artery
-ex. lateral cord is lateral to the axillary artery
-Supraclavicular branches: Dorsal scapular, long thoracic, suprascapular, and subclavian nerve

3. Protection of the Brachial Plexus
Anteriorly
Pectoralis Major
Pectoralis Minor
Clavicle
Posteriorly
Subscapularis
Scapula

4. Drawing the Brachial Plexus

5. Muscles Innervated by the Brachial Plexus
Anterior and Posterior Compartment of Arm
Anterior and Posterior Compartment of Forearm
Latissimus dorsi
Pectoralis Major/Minor
Rhomboids
Serratus Anterior
Subclavius
Subscapularis
Supra/Infraspinatus
Teres Major/Minor
-refer to chart

6. Common Brachial Plexus Injuries
Nerve compression or stretching
Excessive stretching of neck during infants delivery
External trauma, tumors, or inflammation
Superior brachial plexus injuries (more common)
Increase of angle between the neck and shoulder
Shoulder stops, head continues to move
Inferior brachial plexus injuries (less common)
Upper limb pulled superiorly
Breaking a fall
refer to page in Moore

7. “Massage-Induced Brachial Plexus Injury”
Female, 58 years old
Presented to ED with severe pain and weakness in left shoulder after receiving massage therapy
Prior history: 2 years prior, fractured left distal radius and had left shoulder scoped, doctors found torn supraspinatus
Patient had been receiving massage therapy to relieve shoulder pain
Symptoms began 4 sessions into the treatment
Examination:
Normal passive ROM of left shoulder
EMG: decreased recruitment of motor units
of left biceps, left triceps, left deltoid, and
left supraspinatus
Conclusion: Brachial Plexus Injury involving
upper trunk

8. References
Chang, C.-Y., Wu, Y.-T., Chen, L.-C., Chan, R.-C., Chang, S.-T., & Chiang, S.-L. (2015, January). Massage-Induced Brachial Plexus Injury. Physical Therapy Journal, 95(1),
Med School Made Easy. (2014, November 10). Brachial Plexus- How to draw it well in less than 20 seconds. [Video file]. Retrieved from
Moore, K. L., Agur, Anne M.R., and Dalley, Arthur F. (2015). Essential Clinical Anatomy. Baltimore, MD: Lippincott Williams & Wilkins.