Shoulder Joint-Anatomy (1)
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Sternum
Clavicle
Scapula- acromion process and
coracoid process, glenoid fossa and
glenoid labrium, spine of scapula
Humerus- Greater tubercle, Lesser
tubercle, head of humerus,
http://www.readingshoulderunit.com/sh
oulder_anatomy.htm
Shoulder Anatomy (2)
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The shoulder encompasses 5 separate
articulations
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Sternoclavicular (SC) joint
Acromioclavicular (AC) joint
Coracoclavicular joint
Glenohumeral (GH) joint
Scapulothoracic (ST) joint
Sternoclavicular (SC) Joint **
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Joint between the sternum and clavicle
Allows for rotation during movements
like shrugging the shoulders and
reaching above the head.
Supported by 4 ligaments- Fig 8-1
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anterior and posterior SC ligament
Costoclavicular ligament
Interclavicular ligament
Acromioclavicular (AC) Joint**
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Lies between the acromion process and
the clavicle
Has limited motion
Primary ligament: AC ligament
Secondary ligaments
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Coracoacromial ligament
Coracoclavicular ligaments
Glenohumeral (GH) Joint**(1)
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Fig 8-2
“true” shoulder joint
Glenoid fossa of the scapula
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VERY shallow
Head of the humerus (3-4 x larger than
glenoid)-plunger/volleyball example
lacking in bony stability
GH joint** (2)
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Joint is deepened by a meniscus like
structure called the glenoid labrum
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functions to add stability to the joint
Stabilized by two types of stabilizers
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Static stabilizers
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joint capsule
several glenohumeral ligaments
GH joint** (3)
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Dynamic stabilizers
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rotator cuff muscles (SITS)
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Supraspinatus
Infraspinatus
Teres minor
Subscapularis
Scapulathoracic Joint**
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Gliding joint
Scapula rotates to allow full abduction
and adduction
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Called Scapulothoracic rhythm
Several important muscles are stabilzers
including the:
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levator scapula, rhomboids, trapezius, and
serratus anterior
Other shoulder anatomy (3)
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Bursa
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Nerve supply
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Subacromial (clinically most important)
brachial plexus (C5-T1)
Blood supply
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subclavian, axillary artery
Shoulder movements
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Flexion (180) and Extension (80-90)
Abduction (180) and Adduction
Horizontal Adduction/Flexion (130)
Horizontal Abduction/Extension (60)
External rotation (90)
Internal rotation (90)
Throwing Motion Activity
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Cocking, Acceleration, Deceleration
Flexion, Extension, Hyperextension
Abduction, Adduction
Horizontal Adduction/Flexion
Horizontal Abduction/Extension
External rotation, Internal rotation
Elbow Extended, Elbow Flexed
Anatomy of throwing
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Three phases of over arm throwing- Fig
8-10 and Box 8-1
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Preparatory or cocking phase
Acceleration or delivery phase
Deceleration or follow-through phase
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Shoulder goes thru over ???°/sec-knee ???°/sec
when walking
Common injuries during the throwing
motions Box 8-2
Cocking phase
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Arm in horizontal abduction,
hyperextension and external rotation
eccentrically loaded:
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horizontal adductors
internal rotators
scapular muscles
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rhomboids pull scapula back
serratus anterior stabilizes the scapula
Acceleration or delivery phase
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Ball brought forward and released
humeral horizontal add, elbow
extension, rapid internal rotation
romboids relax
Large stresses placed on ligaments,
Arm deceleration/ follow
through
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After ball release, until maximum
shoulder internal rotation, horizontal
adduction are reached
Eccentric loads placed on:
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infraspinatus, supraspinatus, teres major
and minor, lats, posterior deltoid
Preventing shoulder problems
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General muscle strengthening
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Stretching for shoulder capsule, but be careful
Strengthening rotator cuff muscles
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Try and avoid exercises above 90 degrees
including eccentric work
http://www.asmi.org/SportsMed/throwing/thrower10.
html
Throwing Program
Strengthen scapular stabilizers
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push-ups
press-ups
SC joint Sprain
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MOI: direct blow to clavicle or transition
forces from a blow to the shoulder driving
the clavicle out of place
HOPS
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point tenderness over SC joint
bruising, swelling and pain over SC joint
deformity increases with degree; posterior is
serious
Motion decreases with degree
TX-See Field Strategy 8.4
AC joint sprain
“Separated Shoulder”
 MOI: fall on tip of shoulder, direct blow to the
tip of the shoulder, falling on outstretched
hand (FOOSH)
HOPS
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point tenderness over AC joint
bruising, swelling and pain over AC joint
deformity increases with degree; or step deformity
Piano key test positive in 3 degree
TX: place in sling, x-ray; Field Strategy 8.5
GH joint sprains
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Two forms:
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Acute Dislocations
Recurrent subluxations/ dislocations
Acute Dislocations
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MOI: external rotation, abduction,
extension
Most are anterior dislocations
may cause a avulsion of the anterior
portion of the glenoid = Bankart lesion
Acute Dislocations (con’t)
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HOPS
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Intense pain
Tingling and numbness down arm into the hand
arm held at slight abduction, external rotation,
and stabilized against the body
Flattened appearance to the shoulder; acromion
process becomes prominent (Fig 8-14)
inability to move shoulder
Tx-check neurovascular status, sling and ice if
able; referral; DO NOT REDUCE
Chronic dislocations/
subluxation
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MOI: same as acute, force required is
less
HOPS:
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less symptoms than acute
“dead arm syndrome”
TX:
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conservative: therapy
surgery if needed
Rotator Cuff impingement (1)
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Involves several structures:
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supraspinatus tendon micro-tears
subacromial bursa
coracoacromial ligament
Glenoid labrum
long head of bicep
May lead to rotator cuff rupture if
unchecked
Rotator Cuff impingement
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MOI: repetitive microtrauma (overuse)
HOPS:
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pain with activity
pain with overhand motions
painful arch (between 70 and 120 degrees of AB)
Inability to sleep on involved side
+ supraspinatus tests, impingement test
TX: TX: cryotherapy, NSAID’s, rest, gradual
strengthening, retraining of muscles
Bicipital Tendonitis
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MOI- overuse during rapid overhead movements
with excessive elbow flexion and supination;
Bicep tendon gets irritated in the bicipital groove
and may partially sublux
HOPS-pain in anterior aspect of shoulder over
the bicipital groove; athlete may say something
is “popping”; pain with resistive elbow flex and
supination and passive stretch of bicep
Tx- rest from motions that aggravate, ice,
NSAID’s, strengthening and stretching
ROM/Muscle Testing
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Shoulder flexion-Ant Delt/Pec Major
Shoulder extension-Post Delt
Shoulder abduction-Middle Delt
Shoulder adduction-Pec Major/Lats
Shoulder internal rotation-Ant Delt/ Subscapularis
Shoulder external rotation-Infraspinatus/ Teres Major
Horizontal ADD/Flex-Ant Delt
Horizontal ABD/Ext- Post Delt
Scapula elevation, depression, protraction, and
retraction
Special Tests
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Apprehension test (shoulder dislocation)
Empty Can and Drop Arm Tests
(supraspinatus)
Impingement (impingement)
Yergerson’s (biceps tendinitis)
HOPS
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History
Observation
Palpation