Lecture 12: Pectoral Girdle Flashcards
What is the upper limb made up of?
arm, forearm, hand and shoulder (pectoral girdle)
The shoulder joint has the ___ range of motion and is the ___ stable joint. This means it requires ____ of muscles.
widest; least; lots
Whats the fancy word that refers to the arm?
brachium
If you puff your chest out, what type of movement does that do to the pectoral girdle?
retraction
If you pull your shoulder forward, what type of movement does the pectoral girdle do?
protraction
If you shrug, your pectoral girdle is ___ and if you relax back down your pectoral girdle is ___
elavated: depressed
If you raise your arm, you are ____ rotating your glenoid fossa of your scapula.
superiorly
If you clap your hands behind you, you are ____ rotating your glenoid fossa of your scapula.
inferiorly
What main bones makes up the pectoral girdle?
clavicle and scapula
What are the main bone structures of the clavicle?
deltoid tubercle, costoclavicular roughened area (for ligament attachment), subclavian groove (for muscle attachment
What are the 3 angles of the scapula?
superior angle, inferior angle, glenoid fossa
What are the 3 borders of the scapula?
superior border, medial border, lateral border
What are the 3 surfaces of the scapula?
subscapula fossa (anterior view), infraspinous fossa, supraspinous fossa (both posterior view)
What are the 3 protuberene of the scapula?
coracoid (seen on anterior), acromion and spine (seen on posterior)
What are the two main main joints of the pectoral girdle?
sternoclavicular joint
Acromioclavicular
Describe the sternoclavicular joint
saddle shaped synovial joint that sits between the medial end of the clavicle and the manubrium (sternum)
What are the four most important ligaments of the sternoclavicular joint?
Posterior and anterior sternoclavicular ligament
Interclavicular and consto-clavicular ligament (this is the strongest)
Where is the acromioclavicular joint located?
between the lateral end of the clavicle and the medial end of the acromion
what lies inside the acromioclavicular joint and what surrounds it?
intra-articular disc; acromio-clavicular ligament
What two muscles help strengthen the AC joint?
Trapezius and deltoids
What ligament strengthens the AC joint (and the acromioclavicular ligament)?
coraco-clavicular ligament
What is the insertion and origin of the subclavius?
O= costal cartilage of the first rib I= clavicle
What is the insertion and origin of the pectoralis minor?
O= 3rd, 4th and 5th rib I= Coracoid process of the scapula
Primary action of the subclavius?
“braces” the clavicle
Primary action of the pectoralis minor?
depresses the scapula
What is the insertion and origin of the serratus anterior ?
O= ribs 1- 8/9 I= medial border of the scapula
Primary actions of the serratus anterior?
- protracts scapula
- lower fibres help superiorly rotate scapula
What is the insertion and origin of the three regions of the trapezius?
Superior
O= Skull to mid cervicle verterbrae
I= clavicle
Middle
O=beginning of thoracic verterbrae to mid thoracic verterbrae
I= acromion of scapula
Inferior
O= mid to end of thoracic vertebrae
I= spine of the scapula
Primary action of the traps
altogether= retracts scapula superior= elevate scapula mid= retract scapula inferior= depress scapula superior + inferior = superior rotation of scapula
What is the insertion and origin of the levator scapulae
O= cervical vertebraes I= coracoid process of the scapula
Primary action of the levator scapulae
elevate scapula
What are the insertion and origin of the major and mino rhomboids?
O= beginning of the thoracic to mid thoracic I= medial border of the scapula
Primary action of rhomboids
Retract scapula
What is the insertion and origin of the pectoralis major?
O= clavicular head AND the sterno-costal head I= lateral lip of the inter-tubercular groove of humerus
primary action of the pectoralis major
- adducts humerus
- medially rotates humerus
- assist in protraction of scapula (flys on cables)
what is the insertion and origin of the latissimus dorsi?
O= lumbar verterbrae and iliac crest I= floor of inter-tubercular groove on the anterior surface of the humerus
Primary action of latissium dorsi
- adducts the humerus (lat pulldowns)
- medially rotates humerus
- lower fibres help depress scapular by pulling on humerus
What is the apopneurosis of the latissimus dorsi?
It is the flat tendon seen on your lower back
