L09 - Upper Limb Muscles Flashcards
Trapezius muscle origin?
External occipital protuberance; nuchal ligament; spinous processes of C7-T12 vertebrae
What are the superficial posterior axioappendicular muscles?
Trapezius
Latissimus dorsi
Trapezius insertion?
Inner aspect of Lateral third of clavicle; acromion and spine of scapula
Function of Trapezius?
Upper fibres elevate, middle fibres retract and lower fibres depress the scapula.
What are the deep posterior axioappendicular muscles?
Levator scapulae
Rhomboid major
Rhomboid minor
Origin of Levator scapulae?
Posterior tubercules of transverse processes of C1-C4 vertebrae
Insertion of Levator scapulae?
Medial border of scapula
superior to root of spine
Origin of Rhomboid minor?
Spinous process of C7 and T1 vertebrae, nuchal ligament
Origin of Rhomboid major?
Spinous process of T2 - T5 vertebrae
Insertion of Rhomboid minor and major?
Minor = Medial border of scapula (at medial end of scapula spine)
Major = Medial border of scapula from level of spine to inferiorly
Action of Levator scapulae, Rhomboid minor and Rhomboid major?
Levator scapulae = Elevate scapula
Rhomboid minor and major = Retract scapula
Function of Serratus anterior?
protracts & rotates scapula; holds scapula to body
Origin and insertion of Serratus anterior?
Origin = External surface of lateral parts of 1st to 8th ribs
Insertion = Converge into Anterior surface/ inferior angle of medial border of scapula
Explain which nerve is damaged and which muscle cannot function in ‘Winged Scapula’.
Injury to Long thoracic nerve
Arm cannot be completely abducted above the horizontal position because Serratus anterior is unable to rotate the glenoid cavity superiorly
Which muscles contract to rotate the scapula?
Serratus anterior + Trapezius
- Upper fibers of trapezius = rotate glenoid fossa superiorly
- Lower fibers of trapezius = rotate glenoid fossa of scapula inferiorly
- Lower fibers of serratus anterior = rotate inferior angle of scapula laterally
Origin and insertion of pectoralis minor?
Origin = 3rd to 5th rib near costal cartilage
Insertion = Coracoid process of scapula
Origin and insertion of Subclavius?
Origin = Between 1st rib and its costal cartilage
Insertion = Inferior surface of middle third of clavicles
Action of Pectoralis minor and Subclavius?
Both depress scapula
Pec minor = draw scapula inferiorly and anteriorly
Subclavius = Depresses scapula
What are the 9 muscles that move the arm at the shoulder joint?
Danny Likes Playing Super Sonic In The TV Cabin
Deltoid Latissimus dorsi Pectoralis major Subscapularis Supraspinatus Infraspinatus Teres minor Teres major Coracobrachialis
Generally speaking, where are the origins and insertions of muscles that move the arm at the shoulder joint?
- Origin: axial skeleton or pectoral girdle
* Insertion: humerus
Origin, insertion and function of Deltoid muscle?
Origin = Lateral 1/3 of calvicle, acromion and spine of scapula
Insertion = Deltoid Tuberosity of Humerus
Function: abducts arm beyond initial 15 degrees
Origin, insertion and function of Latissimus dorsi?
Origin = spinous process of inferior 6 thoracic vertebrae, thoracolumbar fascia, iliac crest and inferior 3 or 4 ribs
Insertion = Floor** of intertubercular groove of humerus
Function = adducts, medially rotates & extends arm
Insertion of Latissimus dorsi is lateral to which 2 other muscles’ insertion?
Lat. dorsi inserts at the FLOOR of intertubercular groove
Lateral to the FLOOR is Pectoralis major attachment
Medial to FLOOR is Teres major attachment
“Lady D lies between 2 majors”
Pectoralis major origin, insertion and function?
Origin:
Clavicular part = Anterior surface of medial half of clavicle;
Sternal part = sternum &superior 6 CC;
Abdominal part = aponeurosis of External oblique muscle
Insertion = Lateral lip of intertubercular groove of humerus
Function: adducts, flexes and medially rotates the arm
Muscles that form the rotator cuff? What are their collective and own functions?
Supraspinatus = ABduction (initial 15 degrees before Deltoid takes over)
Infraspinatus = Lateral rotation
Teres minor = Lateral rotation
Subscapularis = Medial rotation
Collectively hold the humeral head in the glenoid fossa of the scapula/ stabilize the shoulder joint
Origin and insertion of Supraspinatus?
Origin = Supraspinous fossa of scapula
Insertion = Superior facet of greater tubercule of humerus