Laboratory 16: Pectoral Girdle. Flashcards
What does the pectoral girdle consist of?
Consists of an anterior clavicle and a posterior scapula on each side of the body.
What does the pectoral girdle represent?
An incomplete ring (girdle) of bones as the posterior scapulae do not meet each other but muscles extend from their medial borders to the vertebral column.
Do the clavicles meet?
No
What do the clavicles articulate with?
Manubrium of the sternum.
What does the pectoral girdle do?
Supports the upper limb and serves as the attachment point for various muscles that move the upper limb.
What does this allow for?
Considerable flexibility of the shoulder.
What does the relatively loose attachments of the pectoral girdle do?
They allow for a wide range of movements but shoulder joint injuries are somewhat common.
When is the clavicle easily broken?
The clavicle is a frequently broken bone when on reaches with an upper limb to break a fall.
What does each upper limb include?
A humerus, a radius, and an ulna. Eight carpals, five metacarpals, and fourteen phalanges in the hand.
Where is the humerus?
Upper arm.
Where is the ulna?
Forearm, closest to the body.
Where is the radius?
Forearm (farthest from the middle of the body)
What do the clavicle and the scapula provide?
Provide for attachment muscles of the neck and trunk.
Describe the clavicle
The clavicle is not a straight bone but rather has two curves making it slightly s-shaped and it serves as a bone to keep the upper limb to the side of the body.
Does the scapula connect directly to the axial skeleton?
No
What makes the humerus vulnerable?
The amount of flexibility of shoulder movements. This much flexibility makes the humerus vulnerable to dislocation from the scapula.
What is the sternal end of the clavicle?
Articulates with the manibrum of the sternum.
What is the acromial (lateral end) of the clavicle?
Articulates with the acromion of the scapula.
What is the acromoin scapula?
Lateral end of spine.