Tendinosis & Subacromial Impingement Syndrome

Gene Desepoli, LMT, D.C.

What is the shoulder joint?

• Shoulder joint or shoulder “region?”

• There is an interrelatedness of all moving parts of the shoulder and dysfunction in one joint may cause dysfunction and pain in the others!

“He who treats the site of pain is lost.

- Karel Lewit

7 Joints of the Shoulder Region

1. Glenohumeral

2. Subdeltoid (false joint)

3. Acromioclavicluar

4. Scapulothoracic (false joint)

5. Sternoclavicular

6. Costosternal

7. Costovertebral

The 7 Joints of the Shoulder Region

Bony Anatomy Review

• Scapula

Bony Anatomy Review

• Humerus

Soft Tissue Review

Soft Tissue Review

9 Bursae of Shoulder Region

• Only 2 are clinically important: 1. Subacromial (subdeltoid) bursa

susceptible to impingement, esp. if swollen or inflamed. Frequently

ruptures due to a calcium deposit.

2. Subscapular bursa between anterior scapula and rib

cage

• Note: Bursitis is rarely a primary condition !!!!

Muscle Review

1. Supraspinatus2. Infraspinatus3. Teres Minor4. Subscapularis5. Levator Scapulae 6. Upper Trapezius 7. Serratus Anterior8. Biceps brachii

assists abduction when arm is externally rotated.

9. Deltoid: impingement!

Rotator Cuff

Rotator Cuff

• Muscles do not attach as discreet tendons but blend to form a continuous cuff surrounding the glenoid head.

• Provides dynamic stabilization of the joint due to blending into the capsule.

• Tendons of rotator cuff blend with joint capsule

Rotator Cuff

• Supraspinatus…………Abduction

• Infraspinatus…………..External rotation

• Teres Minor……………External rotation

• Subscapularis…………Internal rotation

Rotator Cuff: Supraspinatus

• Abduction

• Passes under

acromion process

• Most commonly injured or torn

• “Suitcase muscle”

Hypovascularity of the Supraspinatus

• Supraspinatus is considerably hypovascular with respect to the other cuff tendons: “critical zone”

• Tendonitis in this region correlates to hypovascualrity (that progress with age)

Rotator Cuff - Infraspinatus

• External rotation

• Pulls humerus downward with abduction

• Eccentric contraction

Rotator Cuff – Teres Minor

• External rotation

• Pulls humerus downward with abduction

Rotator Cuff - Subscapularis

• Internal Rotation

• Adduction

• Stabilizes humerus

• Pulls humerus downward w/ abduction

• Eccentric contraction

Glenohumeral Joint

• Designed for flexibility at the expense of stability

• Static stabilizers – capsule and ligaments

• Dynamic stabilizers – rotator cuff muscles

Posture and the Glenohumeral Joint

Glenohumeral Joint

Assuming good, normal posture:

• Gravity’s tendency to pull the humerus downward is overcome by superior joint capsule tightness. (vector: pulls humeral head inward for stability)

• Little or no deltoid or rotator cuff muscular effort is needed. (even w/ a small weight in the hand)

Glenohumeral Joint

• With thoracic kyphosis (round shoulders): the rotator cuff must increase tone to compensate for loss of capsular stabilization. Round shoulders may even be a cause of frozen shoulder!!!!

• Increased capsular stress leads to increased collagen production and increased fibrosis

Capsular Support

Capsule taut Capsule loose

Glenohumeral Joint

• With the arm elevated or with round shoulder posture:

• Tension is lost in sup. joint capsule• The rotator cuff muscles contract to provide stabilization. Over time, they fatigue!

• Conditions which compromise stabilization: 1. postural changes - round shoulders = downward scapular rotation 2. rotator cuff weakness/ dysfunction / trigger points

Biomechanics of Abduction of the Humerus

Abduction of Humerus

● Scapula rotates upward (scapulohumeral rhythm) from upper traps and serratus anterior

● Clavicle elevates & rotates backward

● Upper thoracic vertebrae must extend, rotate and bend to same side. The contribution of spinal movement to full arm elevation is often overlooked!

Abduction

• There is the danger of the greater tubercle

hitting the acromion, subjecting the soft

tissue to repeated trauma!

• The head of the humerus must be guided

into inferior glide / depression to prevent

impingement during abduction (actively or

passively) AND it must externally rotate!

Biomechanics of Abduction

External rotation of the humerus occurs due to untwisting of the capsule

Tight internal rotators my prevent this!

Impingement (pinching)

• Bones: acromion and greater tubercle

• Soft tissue:

supraspinatus tendon

& subacromial bursa

Coracoacromial Ligament

Runs from coracoid process to the acromion.Important for a/c joint stabilityMay be a source of impingement

Forms a protective arch over the glenohumeral areatogether with the acromion and clavicle (functions as asecondary restraining arch to prevent superior humeralhead dislocation

Can impinge the supraspinatus tendon and subdeltoidbursa.

Coracoacromial Arch

• An additional site of impingement

Altered Biomechanics

Impingement is prevented by proper biomechanics and by the proper placement of the humerus during abduction.

Causes of impingement therefore can be: muscle imbalance, trauma, trigger points, weakness,

inhibition, pain, arthritis, capsular tightness, muscle memory following injury

eg. scapula doesn’t rotate bursa is swollen and the space is reduced

Shoulder forward shrugging causes impingement.

Scapulohumeral Rhythm

Deltoid Muscle

Muscular Force Couple

• During abduction the humerus must be properly situated for full pain-free movement.

• Force coupling occurs to create smooth pain free movement

eg. trapezius and serratus anterior rotator cuff muscles with deltoid

Abduction of Humerus

• Infraspinatus & Teres Minor

Force Coupling

The Painful Arc

• There is pain during abduction in the range from 45-60 to 120 degrees.

Assessment Tests

• Painful Arc

• Hawkins’ Test / Speeds Test +++

• Subacromial push button (Dawbarn’s)

• Rotator cuff tendonitis assessment

• A/C joint tests

• Labrum disruption tests

• Rotator cuff tears

Progression of Rotator Cuff Tears

Tight pectoral muscles Round shoulders Impingement Supraspinatus Tendonosis/

Tendonitis Calcific Tendonitis Rotator cuff tear !!

• Surgery may be preventable.

• The real heroes and competent level of massage therapy deals with early recognition and prevention.

Corrective exercises

• Correct round shoulders/ergonomics• Restore mobility• Eliminate trigger points• Stretch tight muscles• Strengthen weak muscles• Rehabilitate supraspinatus with scaption. glenoid cavity faces forward, laterally and superiorly

Tendonitis / Tendonosis

Tendonitis / Tendonosis

• Causesoveruse

poor body mechanics

• Pathology

muscle cell damage (tearing, irritation)

microinflammation

fibroblasts

microscarring

Tendinosis / Tendonitis

• Not a true inflammatory condition

• Cell damage causes fibroblasts to

proliferate

• Creates a disorganized scar

(massage and movement)

• Leads to pain and further micro-tearing

Tendinitis / Tendinosis

• Accurate Assessment! 1. pinpoint pain

2. painful active (resisted) contraction3. painful passive overstretching

Highly accurate! Can be applied to any muscle for assessment.

Rotator Cuff Tendinosis

• Supraspinatus:

pinpoint pain at greater tubercle

painful active abduction

painful passive adduction stretch

Rotator Cuff Tendinosis

• Infraspinatus & Teres Minor:

pinpoint pain at greater tubercle

painful active external rotation

painful passive internal rotation stretch

Rotator Cuff Tendinosis

• Subscapularis:

pinpoint pain at lesser tubercle

painful active internal rotation

painful passive external rotation stretch

Treatment of Tendinosis• General Massage

• Remove TrPs which maintain a shortened / tight muscle

• Transverse Friction massage creates a mobile flexible scar causes “good damage” to allow healing

• Strengthen muscle / tendon to tolerate more stress

• Full recovery = the patient can perform 3 sets of 10 strong repetitions

• Ice may be needed before and after Tx. to decrease pain