Shoulder and brachial plexus Flashcards
What muscle forms the rounded lateral contour of the shoulder and what is its nerve supply?
Deltoid muscle, axillary nerve.
What muscle forms the anterior fold of the axilla and what is its nerve supply?
Pectoralis major, medial and lateral pectoral nerve (C6,7,8).
What large muscle inserts into the upper border of the scapula spine and whats its innervation?
Trapezius, spinal accessory nerve (not brachial plexus).
What muscle forms the posterior fold of the axilla and what is its innervation?
Latissimus dorsi, thoracodrosal nerve (C6,7,8).
What is meant by ‘winging scapula’?
Where the scapula lifts away from the thoracic cade. Serratus anterior is not working.
What does the clavicle do?
Strut to provide mechanical advantage. Provides attachment for powerful muscles and ligaments. First bone to ossify, developed in membrane. Most frequently fractured bone.
What is the function of supraspinatus?
Initiates abduction.
What is the function of infraspinatus?
External rotation.
What is the function of subscapularis?
Internal rotation.
What is the function of teres minor?
External rotation.
What is the origin, insertion, function and nerve supply of pectoralis minor?
Origin: Ribs 3-5. Insertion: Scapula:coracoid process. Action: pulls the scapula anteriorly and elevates the thorax during inspiration. Nerve supply: pectoral nerves from brachial plexus.
What are the 5 terminal branches of the brachial plexus?
Musculocutaneous, axillary, radial, median and ulnar nerves.
