The Shoulder Flashcards
What 4 bones are involved in the shoulder joint?
- Humerus, Scapula, Clavicle, Sternum
What are the 3 joints of the shoulder?
- Glenohumeral joint
- Acromioclavicular joint
- Sternoclavicular joint
Sternoclavicular joint kinematics: Elevation?
Clavicle rolls upwards and simultaneously slides downwards into sternum (stretches the costoclavicular ligament)
Sternoclavicular joint kinematics: Depression?
Head of the clavicle rolls downwards and simultaneously slides upwards in the concavity of the sternum (stretches the interclavicular ligaments and superior part of the joint capsule)
Sternoclavicular joint kinematics: Protraction
(opposite to P - retraction gets P, protractions gets A)
Clavicle slides and rolls anteriorly relative to the convex surface of the sternum
Sternoclavicular joint kinematics: Retraction
Concave articular surface of clavicle slides and rolls posteriorly relative to convex surface of sternum (stretches the anterior face costoclavicular ligament and joint capsule)
Sternoclavicular joint kinematics: Anterior and posterior rotation?
During flexion posteriorly rotates 50-60 degrees, and during extension it rotates anteriorly 30 degrees)
Glenohumeral joint kinematics: External rotation
Convex head of humerus rolls backwards and slides forward
Glenohumeral joint kinematics: Internal rotation
Convex head of humerus rolls forward and slides backwards
Glenohumeral joint kinematics: External rotation
Try the movement
Humeral head anteriorises and scapula tilts forward to increase ROM
Glenohumeral joint: Abduction
head of humerus rolls up and slides down
Glenohumeral joint: adduction
head of humerus rolls down and slides up
Supraspinatus
External rotation and abduction
Infraspinatus and teres minor
External rotation and adduction
Subscapularis
Internal rotation
What is scapulohumeral rhythm?
Is the coordinated movement between the scapula, clavicle and humerus during shoulder movements
Phase 1 of scapulohumeral rhythm?
0-30 deg elevation
Humerus 30 degrees abduction
Clavicle 0-5 degrees of elevation
Scapula: minimal movement medially
Phase 2 of scapulohumeral rhythm?
90 degrees elevation
Humerus 40 degrees abduction (up to 90)
Clavicle: 15 degrees of elevation
Scapula: 20 degrees lateral rotation
Phase 3 of scapulohumeral rhythm?
180 degrees abduction
Humerus: 60 abduction, 90 degrees lateral rotation
Scapula: 30-40 degrees lateral rotation
Clavicle: 30-50 posterior rotation, 15 degrees elevation
What is the ratio in scapulohumeral rhythm?
1:2 eg when the arm is abducted 180 degrees - 60 degrees occurs due to rotation of the scapula and 120 degrees occurs due to rotation of the humerus
What would you test for in an AC Joint injury?
Special test: Horizontal adduction & O’Brien’s
ROM: Flexion/extension & internal/external rotation
What would you test for a RC tear
Belly test, Gerber’s lift off & lag sign
External and internal rotation
What would you test for a Subacromial impingement?
Neers, Hawkin-Kennedy, painful arc, empty can, resisted external
(3 out of 5 positive = SAI)
External and internal rotation
What would you test for shoulder instability?
Sulcus sign, load and shift & apprehension test
ROM: Flexion/extension & internal/external rotation
What would you test for SLAP?
Biceps load II test, Jerk & Passive compressive
ROM: Flexion/ext and internal or external rotation
Mechanism of injury SLAP?
Fall on outstretched arm, clicking/popping and pain in overhead movements
Mechanism of injury for an SAI?
Isolated traumatic event or repetitive movements. Sharp catching pain, difficulty reaching behind the back or overhead.
Mechanism of injury for instability?
Anterior (dislocation): forced ER & ABD
Posterior (dislocation): fall onto outstretched, internally rotated arm
Multidirectional instability: No MOI
Mechanism for AC?
Fall on outstretched arm, pain on palpation and compression, pain in ADL’s eg ABD + ER
