8 - Intro to Shoulder Complex Flashcards
What joints make up the shoulder complex?
Glenohumeral Joint
Acromioclavicular Joint
Sternoclavicular joint
Sapulothoracic complex
True or false the GH joint is designed for mobility over stability?
True
How many degrees of freedom does the GH joint have?
3
What type of joint is it?
Synovial and Unmodified ovoid
What fraction of the humeral head articulates with the glenoid fossa?
1/3
What deepens the glenoid fossa?
The glenoid labrum
What action gets pure spin at the GH joint?
Flexion/extension
What action would give you superior roll plus inferior glide at the GH joint?
Abduction
What action would give you inferior roll plus superior glide at the GH joint?
Adduction
What action would give you anterior roll plus posterior glide?
Medial/Internal Rotation
What action would give you posterior roll plus anterior glide at the GH joint
Lateral/External Rotation
In what order would you start to lose the following movements. Internal rotation, external rotation and abduction
ER then abduction then IR
What is the function of the coracohumeral ligament?
To limit ER below 60 degees abduction
Works with the superior glenohumeral ligament
Provides restraint for flex/ext
Is a tunnel for the biceps
What is the function of the superior glenohumeral ligament?
Limits inferior translation in the adducted arm
Limits ER from 0-45 degrees abduction
Put on stretch with biceps during throwing
What is the function of the middle glenohumeral ligament?
Anterior stability at 45 degrees abduction
Anterior stability at 90 degrees abduction
Inferior stability in adduction and ER
What is the function of the inferior glenohumeral ligament?
Primary restraint to all movements anterior, posterior and inferior with the arm abducted beyond 45 degrees
How does the supraspinatus contribute to dynamic stability?
It facilitates GH compression maximally between 45 and 90 degrees and is gone at 150 degrees
How do infraspinatus and teres minor contribute to dynamic stability?
They are humeral head depressors. They allow supraspinatus to compress and prevent subacromial compression
They are also external/lateral rotators and eccentrically decelerate internal/medial rotation
How does subscapularis contribute to dynamic stability?
It is active in all movements of the humerus that require compression and depression
Acts eccentrically to decelerate external rotation
How does the long head of biceps contribue to GH joint dynamic stability?
It increases GH compression with supraspinatus
Applies longitudinal compressive force during deceleration activities
It increases anterior stability in abduction/external rotation by resisting translational stress
What is the primary force couple of scapular lateral rotation?
Upper fibers of traps and seratus anterior
How does the UFT and serratus anterior force couple work?
UFT pull the spine of the scapula up and serratus anterior pulls the medial border and inferior angle laterally
This is all in the initial stages of shoulder flexion (0-90 degrees)
What muscle helps with lateral rotation of the scapula after 90 degrees of shoulder flexion?
The lower fibers of traps
In terms of location of pain where is it typically felt when there is a shoulder dysfunction?
On the lateral aspect of the upper arm (common around the deltoid insertion)
Where would acromioclavicular pain be felt?
On the anterior aspect of the upper arm
Where is C-spine pain typically felt?
neck, upper shoulder and scapula
What does the ending “itis” mean?
Inflammation
What does the ending “opathy” mean?
any pathology
What does the ending “osis” mean?
degenerative over time
True or false: acromioclavicular pain is evident above 90 degrees abduction?
True
In what age range are you most likely to see frozen shoulder/ adhesive capsulitis?
45-60
In what age population are you most likely to see rotator cuff degeneration?
40-60
In what age are you most likely to see or suspect a chondrosarcoma
30+
In what age range are you likely to see or suspect calcium deposition?
20-40
In what population are you likely to suspect GH instability?
15-20
If someone gets relief with placing their hands on their head what type of pain might it indicate?
Nerve root pain
If someone’s arm is fixed in a forward flexion and slight abduction position what might you suspect?
Anterior GH dislocation
If someone’s arm is fixed in an internal rotation and abduction position what might you suspect?
Posterior GH dislocation
What are some indicators od nerve injury?
History of weakness, numbness or paresthesia
Positive test findings when testing the muscle supplied by the nerve
What organs can refer pain to the shoulder/upper arm area?
Liver
Gallbladder (inferior angle on R side)
Heart (left anterior upper arm)
Diaphragm (upper traps, referral to C3-4 dermatome)
What could be some sources of static scapula winging?
Weak muscles (LFT) or having another muscle be tight (peck minor)
Paralyzed SA
Damage to Long Thoracic Nerve
Instability of medial border to remain against chest wall
What is a sulcus sign?
A divit or sulcus in the shoulder which could indicate an anterior or inferior dislocation or just having general laxity at the shoulder
What does a step deformity indicate?
AC sprain
The traps pull up and the weight of the arm pulls downward giving a step down look
What is the painful arc of shoulder movement?
Occurs between 60-120 degrees when the bursa gets impinged under the aromian
