Test 3- Shoulder impairments Flashcards
Four joints of the shoulder
Scapulothoracic
Sternoclavicular
Acromioclavicular
Glenohumeral
Rhythm of the scapula
2: 1 ratio overall
- During the first 60 degrees of flexion or initial 30 degrees of abduction, the scapula does not move and is seeking position of stability in relation to the humerus
- -> this is called the setting phase
Glenohumeral joint
Joint stability is provided by rotator cuff muscles, long head of biceps brachii and extracapsular ligaments
- labrum is very important because it deepens the fossa
- dislocation will be either due to ligament laxity or ligament tear
Rotator cuff
- Supraspinatus (most common for dislocation and pinching Nn)
- Infraspinatus (second most common for injury)
- Teres minor
- Subscapularis
Supraspinatus function
Supraspinatus is the anchor for the shoulder.
-without it you would not be able to reach beyond 90 degrees of abduction
Force couples
Muscles with opposing actions that work together to produce rotation
- Shoulder abduction: deltoid and RTC
- Upward scap rotation: upper and lower trapezius
Shoulder impingement
Umbrella term that includes rotator cuff tears as well as several shoulder muscle injuries (compressions or tears) that result in impingement
-usually gradual onset from overuse
Common muscles of shoulder impingement
- Suprispinatus, long head of biceps, subacromial bursae, and sometimes the infraspinatus
- All get pinched under subacromial arch
Causes of impingement
- Instability of the glenohumeral joint (weakness or joint laxity)
- Dyskinesia: scapula not moving in correct rhythm with humeral head
- Poor posture
- Arthritis: osteophytes can grow down into the subacromial space and stop muscle from moving fully
- Anatomical predisposition
External vs. internal impingement
- External: rotator cuff, or bursae getting compressed/pinched on the superior surface by the acromion
- Internal: rotator cuff, labrum or capsule getting compressed/pinched on the under surface by the humeral head
SICK scapula
A type of dyskinesia:
- Scapular malposition
- Inferior medial border prominence
- Coracoid pain and malposition
- dysKinesis of scapular motion
Painful Arc
Slow arc of motion (abduction) to find out where pain occurs along arc
-Pain from 60-120 degrees: rotator cuff impingement
Hawkins Kennedy Test
Shoulder flexed to 90 degrees, elbow horizontally flexed to 90 degrees> push down lightly just proximal to elbow joint
-Pain= positive shoulder impingement
Neer Test of Impingement
- Stabilization on shoulder
- Shoulder internal rotation
- Full PROM shoulder flexion
- -> pain= positive sign of shoulder impingement
Full can and empty can test
Hand open as if holding a can, arm extended to 90 degrees, practitioner stabilizes at shoulder pushes down on arm
- Full can = external rotation (supination)
- Empty can= internal rotation (pronation); hurts worse, so always start with full can
- ->test for supraspinatus dysfunction