Shoulder Pain Flashcards
Which muscles play an important role in positioning the head of the humerus?
The rotator cuffs
SITS
Describe the mismatch of the humerus and the scapula and the consequence / benefit of this
The head of the humerus is large and the glenoid fossa is smaller and flatter. Benefits are this makes the shoulder extremely mobile but at the sacrifice of stability.
What effect does the contraction of the rotator cuff muscles have on the head of the humerus ?
It translates the head of the humerus down so it can move without any impingement
How do the rotator cuff muscles provide dynamic stability to the GH?
By producing GH compression and inferior glide of the head of the humerus on the glenoid
How does the long head of the biceps provide dynamic stability?
When the GH is laterally rotated it assists with abduction and anterior stabilization and it probably centres the head of the humerus
Which muscle initiates shoulder abduction ?
Supraspinatus especially in the first 60 degrees
What is the role of the deltoids during shoulder abdication
Provides superior translators force and upward rotator u force. Active throughout GH abduction
Describe the role of subscapularis in GH stability
It compresses and stabilizes during elevation and guides the humerus
What forms the coracoacromial arch ?
Corocoid process, acromion, coracoacromial ligament and the superior rim of the glenoid fossa
Why is the coracoacromial arch prone to injury
Because it has many contents in the small and tight space.
What are the contents of the coracoacromial arch ?
Subacromial bursa, supraspinatus tendon, tendon of the long head of the biceps and the coracohumeral ligament
What are the three types of acromion
Type 1 = Flat
Type 2 = Curved
Type 3 = hooked
