Shoulder Joint-Anatomy (1)

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/shoulder_anatomy.htm

Shoulder Anatomy (2)

The shoulder encompasses 5 separate articulations Sternoclavicular (SC) joint Acromioclavicular (AC) joint Coracoclavicular joint Glenohumeral (GH) joint Scapulothoracic (ST) joint

Sternoclavicular (SC) Joint **

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 anterior and posterior SC ligament Costoclavicular ligament Interclavicular ligament

Acromioclavicular (AC) Joint**

Lies between the acromion process and the clavicle

Has limited motion Primary ligament: AC ligament Secondary ligaments

Coracoacromial ligament Coracoclavicular ligaments

Glenohumeral (GH) Joint**(1)

Fig 8-2 “true” shoulder joint Glenoid fossa of the scapula

VERY shallow Head of the humerus (3-4 x larger

than glenoid)-plunger/volleyball example

lacking in bony stability

GH joint** (2)

Joint is deepened by a meniscus like structure called the glenoid labrum functions to add stability to the joint

Stabilized by two types of stabilizers Static stabilizers

joint capsule several glenohumeral ligaments

GH joint** (3)

Dynamic stabilizers rotator cuff muscles (SITS)

Supraspinatus Infraspinatus Teres minor Subscapularis

Scapulathoracic Joint** Gliding joint Scapula rotates to allow full

abduction and adduction Called Scapulothoracic rhythm

Several important muscles are stabilzers including the: levator scapula, rhomboids, trapezius,

and serratus anterior

Other shoulder anatomy (3)

Bursa Subacromial (clinically most

important) Nerve supply

brachial plexus (C5-T1) Blood supply

subclavian, axillary artery

Shoulder movements

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

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 Three phases of over arm

throwing- Fig 8-10 and Box 8-1 Preparatory or cocking phase Acceleration or delivery phase Deceleration or follow-through phase

Shoulder goes thru over ???°/sec-knee ???°/sec when walking

Common injuries during the throwing motions Box 8-2

Cocking phase

Arm in horizontal abduction, hyperextension and external rotation

eccentrically loaded: horizontal adductors internal rotators

scapular muscles rhomboids pull scapula back serratus anterior stabilizes the scapula

Acceleration or delivery phase

Ball brought forward and released humeral horizontal add, elbow

extension, rapid internal rotation romboids relax Large stresses placed on

ligaments,

Arm deceleration/ follow through

After ball release, until maximum shoulder internal rotation, horizontal adduction are reached

Eccentric loads placed on: infraspinatus, supraspinatus, teres

major and minor, lats, posterior deltoid

Preventing shoulder problems

General muscle strengthening Try and avoid exercises above 90 degrees

Stretching for shoulder capsule, but be careful

Strengthening rotator cuff muscles including eccentric work http://www.asmi.org/SportsMed/throwing/throw

er10.html Throwing Program

Strengthen scapular stabilizers push-ups press-ups

SC joint Sprain MOI: direct blow to clavicle or transition

forces from a blow to the shoulder driving the clavicle out of place

HOPS 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 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

Two forms: Acute Dislocations Recurrent subluxations/ dislocations

Acute Dislocations 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) HOPS

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

MOI: same as acute, force required is less

HOPS: less symptoms than acute “dead arm syndrome”

TX: conservative: therapy surgery if needed

Rotator Cuff impingement (1)

Involves several structures: 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 MOI: repetitive microtrauma (overuse) HOPS:

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 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 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

Apprehension test (shoulder dislocation)

Empty Can and Drop Arm Tests (supraspinatus)

Impingement (impingement) Yergerson’s (biceps tendinitis)

HOPS

History Observation Palpation