Shoulder Complex

Question 1

Rotary Cuff Muscles

Answer 1

Rotator Cuff Complex (SSIT):
Supraspinatus: Abducts (slight ext. rot)
Infraspinatus: Ext. Rot (slight Adduction)
Subscapularis: int. Rot
Teres Minor: ext. Rot

Question 2

Muscles acting on the humerus

Answer 2

Pectoralis Major: Flex+ adducts + int rot

Latissimus dorsi: Ext. + adducts + int. Rot+ pulls arm downwards

Deltoid: abducts, anterior = flex + int rot, Posterior = ext + ext rot

Question 3

Muscles acting on Scapular

Answer 3

Trapezius: elevates or depresses, rotate, adduct +stabilizes

Rhomboid Maj and Min: adduct + stabilize + rot +lower lat angle

Levator Scapulae: elevates

Pectoralis Min: draws anteriorly and downwards

Serratus Anterior: stabilizes, Aducts, rot

Question 4

Bursae

Answer 4

Subacromial Bursa: cushions rot cut muscles from acromion + compressed during overhead arm actions

Subcoracoid
Subscapularis

Question 5

Functional Anatomy of Shoulder Complex

Answer 5

• Greatest degree of mobility with limited stability
• Integration of capsule and rot cuff
• scapula stabilizes muscles and the relationship with the other joints of the shoulder Comp. and the glenohumeral joint is critical

Question 6

Acromioclavicular Sprain (AC sprain) Grades

Answer 6

Grade 1: painful horizontal adduction

Grade 2: tear or rupture of ACL lig

Grade 3: rupture of the AC and CC lig. (surgery req)

Grade 4: posterior separation of the clavicle (surgery)

Grade 5: loss of AC and CC lig, tearing of deltoid and trapezius muscle attachments (surgery)

Grade 6: Displacement of the clavicle behind the coracobrachialis (surgery)

Question 7

Glenohumeral (GH) Anterior Dislocations

Answer 7

E: head ant and infer
MOI: FOOSH (ext. rot. + abducted at 90 w/ bent elbow)

S/S: flattened deltoid, head in the axilla, arm carried in Abd + ext rot, mod pain and disability, + apprehension test, Sulcus sign

Question 8

Glenohumeral (GH) Posterior Dislocations

Answer 8

E: head post + infer
MOI: FOOSH (int. rot / forced Add and int. rot)

S/S: sever pain and disability, arm carried ADD and IR, prominent acromion and coracoid process, decreased radial pulse, numbness or paresthesia (brachial plexus or axillary nerve)

Question 9

Treatment for GH dislocations

Answer 9

Immobilize with sling (3 weeks following reduction)
immediate referral

Question 10

Possible Complication of Shoulder Dislocations

Answer 10

Bankart Lesion - ant def of labrum

Hill Sachs Lesion - divot in hum head due to compression

SLAP lesion - defect in superior labrum extending down to attachment of long head of bicep

Question 11

Special Tests for Shoulder Complex

Answer 11

Apprehension Test: tests anterior GH instability, Positive = facial grimace from the patient

Sulcus Sign: GH instability, positive test = depression under the acromial point

Question 12

Clavicular Fraction

Answer 12

MOI: direct impact, FOOSH, fall on tip of shoulder
- NB: most common point middle 1/3