Rotator Cuff Tears Or Tendinosis Flashcards
What is rotator cuff tears or tendinosis
-account for the largest percentage of soft-tissue shoulder disorders
-close relationship and overlap between rotator cuff disorders and shoulder impingement syndrome (ex. Supraspinatus tears may result directly from subacromial impingement)
Characteristics
- may start as minor tendinosis or muscle overload and progress to serious muscle damage as fibres become fatigued and overused
-tensile stress injuries can occur as chronic irritation from micro-trauma or as an acute injury from overwhelming force; severe injury may be avoided if early signs of dysfunction are addressed; proper tissue identification is essential when initiating treatment
-rotator cuff: supraspinatus, infraspinatus, teres minor and subscapularis (stabilize GH joint); also function to control and assist in shoulder movement; when exposed to excessive or repetitive tensile loads greater than the muscle’s strength, injuries develop and vary from minor tendinosis to complete
-supraspinatus most often damaged; subscapularis least often damaged
Supraspinatus
Supraspinatus: easily damaged because of its anatomical arrangement and mechanical demands placed on it; primary function is to stabilize humeral head and assist in GH abduction
-distal muscle and tendon fibres under acromion process make it susceptible to impingement damage between humeral head and acromion process; distal tendon is less vascular also
-strains can be either partial-thickness or full-thickness tears
-tears result from excessive tensile loading but can be aggravated by subacromial impingement
-chronic compression causes degeneration which increases risk of tearing
-tensile loads can cause tendinosis and not a tear but the pain is similar to a minor tear (extends healing time)
Infraspinatus and Teres minor:
Infraspinatus and Teres minor: become dysfunctional due to tensile stress; can be eccentrically overloaded (throwing); at the end of the motion they slow the momentum of the arm; fibre fatigue can result from continued stress; begins as a low-level tendinosis and may end up as a full tear; develop at the musculotendinous junction; easier to identify than other rotator cuff muscles
Subscapularis
Subscapularis: sustains few strains or tendon irritation; shares its main action with pectoralis major, latissimus dorsi, anterior deltoid and teres major (prevent subscapularis overload); GH joint capsule restricts lateral rotation before there is enough tensile load to cause strain
-can be strained during a shoulder dislocation; primary support for anterior GH joint (assisted by biceps brachii long head tendon)
-subacromial compression occurs when the arm is brought into full flexion or abduction
-chronic periods of holding the shoulder in these positions can also lead to fibre degeneration and tissue damage
-tissue degeneration from previous stress or trauma followed by an acute injury can result in strains
-pain can be mild aching to severe acute
-difficult to localize, typically aggravated in abduction and forward flexion
-night pain is common due to sleep position where humeral head may be jammed against underside of acromion process (worse when lying on affected side)
-affects those over 40 due to decrease in effective tissue repair, pathological changes in shape of
acromion process
History
History: acute or chronic, ask about repetitive motion or shoulder injuries; ask about activities or occupations that require overhead or throwing activities that cause muscle damage
Supraspinatus: tears occur when muscle-tendon unit is suddenly loaded; ask about acute injuries (lifting something heavy or falling on an outstretched arm); pain described as deep in shoulder, difficult to point to
Infraspinatus and teres minor: activities that might cause sudden or repetitive eccentric forces on posterior rotator cuff muscles; pain in posterior shoulder region, can reproduce pain by pressing on damaged tissue
Subscapularis: torn with severe trauma (dislocation); with initial onset, ask about strong forces; forced lateral rotation (dislocation/subluxation)
Tendinosis: all four rotator cuff muscles: gradual onset of pain, strong aching pain with activity, dissipates with rest
Observation
Observation: may be inflammatory response, acute tears of infraspinatus or teres minor can be visible; redness, swelling or bruising; tears of subscapularis not visible but may be inflammation
-tendinosis has no visible signs
-tendinitis can occur at a low level and rarely visible
-bone spurs or osteophytes that cause tissue tearing visible with x-ray
-visible compensating patterns of movement or pain avoidance are evident
-apprehension when perform active or resisted abduction
Palpation
Palpation: tenderness and reproduction of pain; fibrosity and thickening may be felt in muscle/tendon; excess heat from inflammation, muscular hypertonicity in rotator cuff and surrounding muscles
Supraspinatus: tear difficult to palpate under acromion process, may be palpated in the supraspinous fossa or just inferior to acromion process on lateral aspect of shoulder (may also feel hooked acromion)
Infraspinatus and teres minor: easily palpated at musculotendinous junction
Subscapularis: inaccessibility of muscle so difficult to palpate; use caution because of brachial plexus and vasculature near distal end of muscle
Range of Motion and Resistance Testing
AROM: supraspinatus tears or tendinosis: pain with active abduction, with impingement, may be pain with flexion also; other muscles not likely to produce pain without significant resistance and starting in neutral position; same is true for supraspinatus with medial rotation; may be pain at end of motion in the opposite direction from muscle’s concentric action due to stretching damaged fibres
PROM: supraspinatus tears or tendinosis: pain with abduction or flexion due to compression of damaged tissue; other muscles produce pain at end ROM when stretched
MRT: pain and weakness from stressing tissue and reflex muscular inhibition from rotator cuff tears or
tendinosis when primary action is tested
Supraspinatus: resisted abduction painful and weak
Infraspinatus and teres minor: resisted lateral rotation painful and weak
Subscapularis: resisted medial rotation painful (weakness counteracted by other muscles)
Special tests:
Drop-Arm: standing, raise affected arm to 90° abduction; watch pattern of movement, may have difficulty bringing arm into position and visible apprehension or discomfort evident, movement may not be smooth or coordinated, may drop arm; if able to hold arm in position, slowly lower arm
-positive test if patient cannot slowly lower arm or significant pain
-may place slight resistance to arm for additional load
-assess supraspinatus with a 2nd or 3d degree tear
-reflex muscular inhibition shuts off motor signals with sudden pain sensation
Differential Evaluation:
subacromial bursitis, shoulder impingement, calcific tendinitis, suprascapular neuropathy, bicipital tendinosis, cervical radiculopathy, myofascial trigger point referrals, acromioclavicular joint injury, frozen shoulder/adhesive capsulitis, glenohumeral subluxation
Suggestions for Treatment:
treated according to their severity and whether they are acute/chronic; encourage collagen production or facilitate healthy scar tissue repair; deep transverse frictions, deep longitudinal stripping, pin-and-stretch or passive/facilitated stretching; address hypertonic and compensating muscles
