Shoulder and Arm Flashcards
What is the correct anatomical position for the palms and thumb?
Palm is anterior
Thumb is the most lateral digit
What is the only bone connecting the upper limb with the rest of the skeleton?
The clavicle
What composes the pectoral girdle (shoulder girdle)?
Scapula + clavicle
What is an anterior dislocation?
Rupture of the anterior sternoclavicular ligament
What is a posterior dislocation?
Rupture of the posterior sternoclavicular ligament
*More serious
*Medial end of the clavicle may compress arteries
During a clavicle fracture what happens to the medial and lateral fragment?
Medial: lifted by the sternocleidomastoid muscle
Lateral: sags with upper limb
What is the range of motion at the sternoclavicular joint?
- rotate around its own longitudinal axis
- Clavicle can be raised up to 60 degrees
- Can move 30 degrees anteriorly or posteriorly during protraction and retraction of the scapula
What is the Acromioclavicular joint between?
The acromion and clavicle
What does the Acromioclavicular joint do
Supports entire weight of scapula and upper limb
What is a grade I or II Acromioclavicular joint dislocation
Only joint capsule affected (AC joint)
What is a grade II Acromioclavicular joint dislocation?
Coracoclavicular ligament is torn
*The shoulder falls away from the clavicle
What type of joint is the glenohumeral joint?
Ball-and-socket, synovial joint
What is a common fracture site of the humerus?
The surgical neck
What is the coracoclavicular ligament between?
Clavicle and coracoid process of the scapula
What does the coracoacromial arch do?
Resist superior movements of the humerus
*connects scapula to scapula
*acromion to Coracoid process
what are the rotator cuff muscles?
Subscapularis
Infraspinatus
Teres minor
Supraspinatus
What is the origin, insertion, and action of the Subscapularis muscle?
O: Subscapular Fossa of scapula
I: Lesser tubercle of Humerus
A: Medially rotates and adducts the Humerus
What is the origin, insertion, and action of the Infraspinatus muscle?
O: Infraspinous fossa of the scapula
I: Greater tubercle of humerus
A: Laterally rotates the humerus
What is the origin, insertion, and action of the teres minor muscle?
O: Lateral border of the scapula
I: greater tubercle of humerus
A: Laterally rotates the humerus
What is the origin, insertion, and action of the Supraspinatus muscle?
O: Supraspinous fossa of the scapula
I: Greater tubercle of humerus
A: Initiates abduction of humerus; stabilizes abducted arm
What is the Supraspinatus muscle deep to?
The trapezius and deltoid muscle
What is the infraspinatus, teres minor muscle deep to?
Infraspinous fascia
What do all four rotator cuff muscles do?
Stabilizing the glenohumeral joint
*Pulls the humeral head close to the glenoid fossa
What is the nerve and blood supply to the Supraspinatus and infraspinatus muscle?
Suprascapular nerve and artery
What goes over the superior transverse scapular ligament
Suprascapular Artery (Army over the bridge)
What goes under the superior transverse scapular ligament?
Suprascapular Nerve (Navy under the bridge)
What is the nerve supply of the serratus anterior muscle?
Long thoracic nerve
What is the origin, insertion, and action of the deltoid muscle?
O: Lateral spine of the scapula, acromion, lateral clavicle
I: Deltoid tuberosity of the humerus
A: Abduction to shoulder height
What is the action of the clavicular part of the deltoid?
Flexes, medially rotates humerus
What is the action of the middle (acromion) part of the deltoid?
Abducts the humerus from 15 degrees to should height
What is the action of the spinal (posterior) part of the deltoid?
Extends, laterally rotates humerus
What is the groove between the pectoralis major and the deltoid?
Deltopectoral groove
What is the function of bursae?
Reduces friction between adjacent mobile structure (found deep to tendons)
What is the blood supply to the serratus anterior muscle?
Lateral thoracic Artery
What happens if the long thoracic nerve is damaged
Winged scapula
What is the Origin, Insertion, and action of the teres major muscle?
O: inferior angle of the scapula
I: Anterior side of humerus
A: abducts and medially rotates arm