9.1 Shoulder Conditions Flashcards
What is the definition of impingement syndrome?
Impingement syndrome is a general term describing shoulder pain, typically diagnosed following a positive mid range painful arc as well as various other impingement special tests. Typically referring to pinching on structures in the subacromial space during humeral elevation.
What structures in the subacromial space can get pinched with impingement syndrome?
- Supraspinatus tendon
- Subacromial bursa
- Biceps long head tendon
At what range in the painful arc with their GH doing joint pain? Acromioclavicular joint pain?
- GH joint: in 45° to 120°
- AC joint: in 170° to 180°
What are some intrinsic factors that cause primary impingement at the subacromial/suprahumeral space?
- Vascular changes in rotator cuff tendons (due to secondary disease process, age)
- Structural variation in the acromion (flat vs hooked)
- Trophic changes to the humeral head, AC joint, coracoacromial arch (fibrosis and thickening of coracoacromial ligament)
- Post-traumatic/postsurgical scarring
What are some extrinsic factors resulting in decreased suprahumeral space and repetitive trauma to soft tissue during humeral elevation?
- Posterior capsule tightness causes anterosuperior translation of humeral head
- Weak external rotator/short internal rotators: restricts ability for humerus to externally rotate during abduction and restricts ability for greater tubercle to clear acromion (anterior cuff dominates posterior cuff)
- Deltoid overpowers rotator cuff: net superior translation of humeral head during abduction
- Poor scapular stability and muscular imbalances: if scapula is not stable, it doesn’t allow for optimal length-tension relationship of rotator cuff muscles
- Hyperkyphosis: places scapula into position rotation, protraction and anterior tipping. Also places humerus into a position of internal rotation
- Rotator cuff (and biceps LH) overuse and fatigue: if these muscles are fatigued from overuse, they no longer provide the dynamic stabilizing and compressive forces required for normal joint mechanics
- Tendonopathy: inflammation (edema) decreases subacromial space with tendinitis, thickening/fibrosis decreases subacromial space with tendinosis
- Supraspinatus: pain on palpation of tendon inferior to anterior of chromium, painful GH arc, positive impingement test
- Infraspinatus: pain on palpation of tendon inferior to posterior corner externally of acromion when patient externally rotates and horizontally adducts, painful GH arc with abduction and flexion
- Biceps long head: pain on palpation of tendon in bicipital groove, positive speeds test
- Chronic inflammation and tendon overload can also stimulate the formation of osteophytes in the joint, which can further damage the surrounding musculature
What is difficult to differentiate from supraspinatus tendinitis because of the anatomical proximity?
Subacromial bursitis
Where might subacromial bursitis refer pain to?
To the deltoid insertion
How might subacromial bursitis present?
- Acute burning or sharp pain
- Painful “catch” when lowering arm from full abduction
- Pain on release of speeds test (Isometric shoulder flexion)
- May refer pain to deltoid insertion
In the cases of rotator cuff tears, either partial or full thickness, what should be emphasized during treatment?
Treatment needs to emphasize optimal joint/muscular mechanics. This includes normalizing posture, muscle imbalances (Length, strength, endurance) and tissue health/extensibility.
What is secondary impingement?
Due to instability (multi or unidirectional) impingement is the secondary result
What are some causes of secondary impingement?
- Lax connective tissue, greater translation of humeral head in one or multiple directions
- Labral or rotator cuff tears
- Dislocation
What’s the aka for primary frozen shoulder?
Adhesive capsulitis
What is the capsular pattern for shoulder?
External rotation, abduction, internal rotation, flexion
Where are some causes of secondary frozen shoulder?
- Another issue presents in which there is a period of pain and/or restricted motion that results in chronic inflammation and capsular adhesion
- OA/RA
- Immobilization (fracture, dislocation, surgery)
- Trauma
What’s the onset, age of onset, and cause of primary frozen shoulder?
- insidious onset
- usually between ages 40-60
- more prevalent in women
- unknown cause
- some studies have linked chronic inflammation in musculotendinous or synovial tissue (rotator cuff, biceps tendon, joint capsule) to the development of primary frozen shoulder