Week 2 Pectoralis- Severson Flashcards
What muscle serves to medially rotate and adduct the upper extremity?
Pectoralis Major
The axillary artery is divided into thirds… what six arteries branch off from these thirds?
1st: Superior Thoracic artery
2nd: Thoracromial and lateral thoracic artery
3rd: Arterial circumflex humoral arter, posterior circumflex humoral artery, subscapular artery
From which artery does the axillary artery originate and where?
A continuation of the subclavian artery, it becomes the axiallary artery at the first rib
The axillary artery become what?
The brachial artery
What ventral rami contribute to the brachial plexus?
C5, C6, C7, C8, and T1
Anterior Division supplies what cords of the brachial plexus?
Medial and lateral cords
Posterior Division supplies what cords of the brachial plexus?
Posterior Cords
The medial and lateral cords give rise to what nerves?
Musculocutaneous
MediaN
Ulnar nerve
Posterior cords gives rise to what nerves?
Axillary and radial nerves (primary extensors of the upper limb)
What clinical deficit is manifest with axillary nerve injuries?
deltoid atrophies
Possible loss of sensation may occur over the lateral side of the proximal part of the arm
Limb hangs at side in a medial rotation at the shoulder with the forearm pronated in the “waiter’s tip” position…. what has been injured?
Upper Brachial plexus is injured (involves C5-C6)
Results from blow to the region that extends the angle between the neck and shoulder, possibly getting through from a motorcycle or horse, or during birth
What causes the “claw hand”
lower brachial plexus injuries
Not very common
Result from sudden upward pull of the shoulder
Injury effects lower trunk (C8-T1)
Paralysis generally affecting the area supplied by the ulnar nerve
**weakness of the forearm flexors of the fingers and thumb, and small muscles of the hand
What produces the “wrist drop”?
Injury to the radial nerve
Radial nerve supplies the primary extensors
May occurs during incorrect use of crutches
