Pectoral Girdle - summary, joints (dave's notes) Flashcards
What are the bones of the pectoral girdle?
The clavicle and scapula
What does the scapula represent?
Fusion of the scapula proper and the coracoid
How is the clavicle formed?
Ossifies in membrane
What are the joints of the pectoral girdle?
Sternoclavicular and acromioclavicular. The remainder of attachment is purely muscular
Describe the embryology of the pectoral girdle
Muscles developed in the upper limb are supplied by branches form the brachial plexus. Some uscles migrate out (lat dorsi), and some migrate in (SCM, trapezius)
What is the function of the pectoral girdle?
Mobility on the thorax thus aiding shoulder joint movement ->thoracohumeral articulation
What type of joint is the sternoclavicular joint?
The sternoclavicular joint is an atypical synovial joint with features of ball and socket
What are the joints of the pectoral girdle?
sternoclavicular
Acromioclavicular
Separated into two cavities by a cartilaginous disc
Describe the articular surface of SC joint
Set at 45’ with the xx? perpendicular.
What projects above the manubrial facet? What lies here?
The sternal end of the clavicle projects well above the upper margin of the manubrial facet The interclavicular ligament.
Describe the capsule of the SC joint
Thickened in front and behind
What is the nerve to the SC joint?
The medial supraclavicular nerve
What is the movement of the SC joint?
The fulcrum is at the costoclavicular ligament. Rotation also occurs at this joint
What provide stability of the SC joint?
Ligaments, especially costoclavicular
What type of joint is the acromioclavicular joint? Between which bones? Surrounded by what?
An atypical synovial joint, plane type between the overhanging lateral end of the clavicle and the under hanging medial border of the scapula. Surrounded by a sleeve-like capsule.
