Upper Limb 1 Station 3 - Pectoral Girdle, Scapular Movements and Muscles Flashcards
What is the pectoral/shoulder girdle?
The set of bones which connects the upper limb to the axial skeleton on each side
What bones are in the pectoral girdle?
Clavicle
Scapula
What is the joint called where the scapula and the clavicle meet?
Acromioclavicular joint
Where on the scapula does the clavicle join?
Acromion process
The entire upper limb and girdle articulate at one small joint only - what one is it?
Sternoclavicular joint
How do you tell if the clavicle is in the correct plane/direction?
The medial end should stick out anteriorly more
Medial part that articulates with the sternum is larger than the one that joins onto the acromion
Where is the conoid tubercle?
Inferior surface nearer lateral end
Function of conoid tubercle?
Attachment point for the conoid ligament which binds the clavicle to the coracoid process of the scapula
What part of clavicle is weakest?
Junction of middle and lateral thirds
What type of joints are the acromioclavicular and sternoclavicular joints?
AC - synovial plane
SC - synovial saddle
What muscles work to elevate the scapula?
Levator scapulae
Upper trapezius
Rhomboids
What muscles depress the scapula?
Lower trapezius
Pectoralis major and minor
What muscles protract (forwards movement) the scapula?
Serratus anterior
Pectoralis major and minor
What muscles retract (backwards movement) the scapula?
Middle fibres of trapezius
Rhomboids
What muscles retract (backwards movement) the scapula?
Middle fibres of trapezius
Rhomboids
What muscles laterally (up) rotate the scapula? Therefore elevating the glenoid cavity.
Trapezius
What muscles medially (down) rotate the scapula? Therefore depressing the glenoid cavity.
Levator scapulae
Rhomboids
Pec Major
(Gravity also)
What is the scapulo-humeral rhythm?
For abduction of the arm, beyond the first 30 degrees (where all movement is done at the shoulder joint)
- for every 3 degrees of abduction, 2 occurs at the shoulder joint and 1 occurs at the scapula-thoracic joint.
What is the scapulothoracic joint?
The movement of the scapula on the thoracic wall - not actually a joint
