Ortho- Shoulder Flashcards
what is the blood supply to the deltoid
thoracoacromial artery and anterior and posterior humeral circumflex artery
what are the muscles of the anterior compartment of the arm
- biceps brachii
- coracobrachialis
- brachialis
presents with:
Shoulder pain/weakness over lateral deltoid exacerbated by overhead activities and at night
rotator cuff tear
what is the action of the deltoid
abduction
flexion
extension
what are the actions of the teres minor
lateral rotation
what nerve innervates the teres minor
axillary nerve(C5, C6)
what is the blood supply to the teres minor m.
subscapular and circumflex scapular artery
what nerve innervates the infraspinatus
suprascapular nerve (C5, C6)
what are the attachments of the trapezius
ligamentum nuchae and spinous processes (T1-T12)
to
lateral 1/3rd of clavicle, acromion and scapular spine
what nerve innervates the teres major m.
lower subscapular nerve (C6, C7)
what type of shoulder dislocations are there
- anterior (95-97%)
- posterior (2-4%)
- inferior (0-0.5%)
what does the axillary nerve innervate
deltoid, teres minor
*runs w/ posterior circumflex humeral artery
what 4 joints make up the shoulder?
- Glenohumeral joint - a shallow cavity (hole) in the scapula where the humerous sits.
- Acromioclavicular (AC) joint - between the clavicle and scapula.
- Sternoclavicular (SC) joint - between the clavicle and sternum (chest bone).
- Scapulothoracic joint - where the scapula meets the ribs at the back of the chest.
what is the function of the aconeus
extension of forearm
what is the blood supply of the trapezius
superficial branch of transverse cervical artery
what are the attachments of the deltoid
clavicle to scapula to deltoid tuberosity of humerus
what are the actions of the trapezius
rotation, retraction, elevation and depression of scapula, shrug shoulders
what are rotator cuff muscles
- suprspinatus
- infraspinatus
- teres minor
- subscapularis
what is the triceps brachia innervated by
radial nerve
PE: prominence of posterior shoulder, holds arm ADDucted and INTERNALLY rotated
posterior shoulder dislocation
what do the anterior compartment muscles all have in common?
- ALL innervated by musculocutanenous nerve
- ALL supplied by muscular branch of brachial artery
- ALL function of flexion of arm and/or forearm
action of biceps brachii
flexion of arm and forearm
supination of forearm
what are the attachments of the infraspinatus
infraspinatous fossa
to
greater tubercle
most common complication of a shoulder dislocation
axillary nerve damage (runs inferiorly to humeral head and wraps around surgical neck of humerus)
*check sensation of “shoulder badge” and deltoid strength
what are the attachments of the subscapularis
subscapular fossa
to
lesser tubercle
MOI: blow to abducted externally rotated and extended arm
anterior shoulder dislocation
what is the blood supply to the infraspinatus m.
suprascapular and circumflex scapular artery
what are the attachments of the teres minor
middle 1/3rd of scapula
to
greater tubercle
actions of coracobrachialis
flexion
adduction of arm
what are the actions of teres major
extension, adduction, medial rotation
action of triceps brachia
extension of arm (long head)
extension of forearm (long, lateral, and medial heads)
what are the actions of the infraspinatus
lateral rotation
actions of brachialis
flexion of arm
PE: slightly ABDucted and EXTERNALLY rotated
anterior shoulder dislocation
what tests assess rotator cuff tear
- Active painful arc test- pain with abducting arm to side around horizontal
- Neer Test- examiner stabilizes scapula while forcing arm into maximal elevation
- Hawkins-Kennedy test- Tests subacromial impingement
- Drop arm test (failure to smoothly control shoulder adduction)-Supraspinatus test
- Raise arms to side as high as possible and then lower arms to 90 degrees (arm will drop)
- Weakness in external rotation
what is the antagonist m. to the deltoid
latissmus dorsi
what is the blood supply to the subscapularis m.
subscapular artery
what nerve innervates the trapezius
Accessory nerve (motor), cervical spine (motor and sensation)
what nerve innervates the subscapularis
subscapular nerve (C5, C6)
what is the aconeus innervated by
radial artery
what is the blood supply of the teres major
subscapular and circumflex scapular arteries
MOI: blow to the anterior portion of the shoulder, axial loading of an adducted and internally rotated arm, seizure convulsion
posterior shoulder dislocation
what are the attachments of the teres major m.
medial lip of intertubercular groove of humerus
what are the attachments of the supraspinatus
-supraspinatous fossa (superior to scapula)
to
-greater tubercle of humerus
what ligaments stabilize the GH joint
- Anterior: GH ligament (superior, middle, inferior)
- Superiorly: coacoacromial ligament and coracohumeral ligament
- Posterioinferiorly: No lig!- joint capsule only
*Labrum: fibrocartilage attached to the rim of the shoulder socker
what nerve innervates the deltoid
axillary nerve
what is the blood supply to the supraspinatus
suprascapular and circumflex scapular artery
what nerve innervates the supraspinatus
suprascapular nerve (C5, C6)
what imaging could assess a rotator cuff tear
- plain radiograph
- MRI**
what are the actions of the subscapularis
medial rotation
MOI: axial loading w/ the arm fully abducted for forecul hyperabduction
inferior shoulder dislocation
what are the actions of the supraspinatus
abduction and lateral rotation
