Kinesiology of Upper Extremity Flashcards
What is the function and location of the anterior shoulder girdle muscles?
Serratus Anterior: Originates on the 1st to 9th rib and inserts to the entire medial border of the scapula. Hence, it abducts the scapula and is an upward rotator, it also enables powerful forward motions of the arms such as throwing and ensures that the scapula is not posteriorly displaced from the thorax.
Pectoralis minor: Located on the 3rd to 5th ribs and inserts to the coracoid process of the scapula. Hence it is a depressor, a downward rotator, an abductor, and a posture stabilizer, which worsens a kyphotic posture by tilting the scapula forward should it be weakened.
Name all the anterior and posterior shoulder girdle muscles.
Anterior muscles: Serratus anterior and Pectoralis minor.
Posterior muscles: Levator scapulae, Rhomboids, Trapezius.
What is the function and location of the posterior shoulder girdle muscles?
Trapezius: Originates from the base of the skull, the whole thoracic vertebrae (C7 -T12), and inserts on the spine and acromion process of the scapula as well as the lateral clavicle. Its functions differ from its regions.
- Upper: Elevation and upward rotation
- Middle; Adduction of scapula
- Lower: Downward rotation and depression
Rhomboids: Originates from C7 and T1-T5, inserts on the medial border of the scapula, hence is responsible for adduction, and elevation and assists with downward rotation.
Levator scapulae: Originates from transverse processes of C1-C4, inserts on superior angle of scapulae. Hence, is responsible for the elevation of the scapula.
What are the muscles that move the glenohumeral joint?
Latissimus dorsi, teres minor, pectoralis major, deltoids, and rotator cuffs. (Supraspinatus, infraspinatus, subscapularis, teres minor)
What are the 2 portions of the pectoralis major and its functions?
The 2 portions include the clavicular and the sternocostal portions. The clavicular portion flexes, internally rotates and horizontally flexes the humerus. The sternocostal portion acts as an extensor.
State the movements of the different portions of the deltoids.
Anterior: Flexor, Internal rotator, horizontal flexor
Posterior: Extensor, External rotator, horizontal extensor
Middle: Adductor
Why is the teres minor commonly referred to as the little lat?
The functions of the teres minor and the latissimus dorsi are similar and their insertion points are near each other on the medial aspect of the proximal humerus. They both act concentrically to produce adduction, internal rotation, and extension.
