Unit One Brachial Plexus Flashcards
Thoracic outlet syndrome produced by
Compression of the components of the brachial plexus, subclavian artery or subclavian vein
What are the subtype of thoracic outlet syndrome
Neurogenic TOS, arterial TOS and venous TOS
The compression of TOS can be
Positional or static
What occurs during positional TOS
Caused by movement of the clavicle and shoulder girdle with arm movement
What occurs during static TOS
Caused by abnormalities or enlargement of the various muscles surrounding the arteries, veins and brachial plexus
The presence of a cervical rib can cause a form of TOS due to
Compression of the lower trunk of the brachial plexus or subclavian artery
Cervical rib and what can cause TOS
Scalenus muscle
Brachial plexus is formed by union of
Anterior rami of C5-C8 and T1
What are the roots of the brachial plexus
C5-C8, T1
The brachial plexus roots pass laterally between
Anterior and middle scalene muscles
The brachial plexus roots run along with what vessel
Subclavian artery
What joins the brachial roots as they pass between the scalenes
Sympathetic fibers from the middle and inferior cervical ganglia
What trunks form from the brachial roots
Superior, middle and inferior
Superior trunk formed by
C5 and C6
Middle trunk forms from what root
C7
Inferior trunk forms from what root
C8 and T1
As the trunks pass lateral to the first rib each trunk then
Splits into anterior and posterior divisions
When do the trunks become divisions
When passing under the clavicle and enter the cervicoaxillary canal
Anterior division of the brachial plexus innervates
The muscles of the anterior compartment in the arm and forearm
The posterior division of the brachial plexus innervates
The muscles of the posterior compartment of the arm and forearm
Divisions of the brachial plexus then forms what and where
Cords and area superior to the pectoral minor muscle
Superior and middle anterior divisions unite to form
The lateral cord
Inferior anterior division of the inferior trunk forms
The medial cord
Posterior divisions unite to form the
Posterior cord
What are the branches from the rami of the BP
Dorsal scapular and long thoracic
Dorsal scapular nerve innervates
Rhomboids and levator scapulae
Long thoracic nerve innervates
Serratus anterior
Dorsal scapular nerve comes off which rami
C5
Long thoracic nerve comes off what rami
C5, C6 and C7
Branches from the trunk of BP
Nerve to subclavius
Subclavius nerve innervates
Subclavius
What branch comes off the division of BP
Suprascapular nerve
Suprascapular nerve innervates
Supraspinatus and infraspinatus
The supraclavicular branches are
Root branches, trunk branches, and division branches
The dorsal scapular nerve pierces
Middle scalene and passes inferiorly to the rhomboids
C5 also gives a root to what nerve
Phrenic nerve
Phrenic nerve comes from
C3-C5
Nerve to subclavius comes from what trunk
Superior
The nerve to subclavius passes directly to the inferior surface of the
Clavicle and gives branch to sternoclavicular joint
Suprascapular nerve comes from what division of BP
Anterior division of superior trunk
Suprascapular nerves runs parallel to
Suprascapular artery
How does the suprascapular n run to the scapula
Goes underneath suprascapular ligament of suprascapular notch to supply the supraspinatus muscle and around the greater scapular notch to the infraspinatus muscle
What are the nerves that come from the cords
Lateral pectoral, medial pectoral, medial brachial cutaneous, medial antebrachial cutaneous, lower subscapular, upper subscapular, thoracodorsal nerve
Lateral pectoral nerve innervates
Pectoralis major
Medial pectoral innervates
Pectoral major and minor
Medial brachial cutaneous innervates
Skin and medial arm
Medial antebrachial cutaneous nerve innervates
Skin and medial forearm
Lower subscapular nerve innervates
Teres major and subscapularis
Upper subscapular nerve innervates
Subscapularis
Thoracodorsal nerve innervates
Latissimus dorsi
Brachial plexus can be divided into what two parts
Supraclavicular and infraclavicular
Supraclavicular contains
Root, trunk and divisions
Infraclavicular contains what of BP
Cords and branches
What are the infraclavicular cords
Lateral, posterior, and medial
what are the branches off of the lateral cord
Musculocutaneous, median, and lateral pectoral
Musculocutaneous nerve innervates
Coracobrachialis, biceps brachii and brachialis
Lateral pectoral innervates
Pectoralis major
What are the branches off of the posterior cord
Axillary, radial, upper subscapular, lower subscapular and thoracodorsal
Axillary nerve innervates
Teres minor and deltoid
Radial nerve innervates
Triceps brachii, brachioradialis, extensor carpi radialis
Upper subscapular innervates
Subscapularis
Lower subscapular nerve innervates
Subscapularis and teres major
Thoracodorsal nerve innervates
Latissimus dorsi
What are the branches off of the medial cord
Ulnar, median nerve, medial pectoral, medial brachial cutaneous, medial antebrachial
Medial pectoral nerve innervates
Pectoralis major and minor
The median nerve is formed from
Medial and lateral cord