Bones:

Clavicle
Scapula
Humerus
Sternum

Articulations:

1) Sternoclavicular
2) Acromioclavicular
3) Glenohumeral
4) Scapulothoracic

1) SC Sternoclavicular
Only direct connection between arm and trunk

Movements: Superior / Inferior
Anterior / Posterior
Rotation
Combination (Up and Back ..)

2) AC Acromioclavicular

Weak Joint
Common site for Shoulder sprains
Connection between the scapula and the clavicle
Step up to the clavicle

3) GH Glenohumeral

Head of the Humerus articulates with the shallow gleniod fossa of the scapula

Passive Stability Glenoid Labrum
Capsular Ligaments

Active Stability Deltoid Muscle
Rotator Cuff Muscle

4) Scapulothoracic

Not a true joint – articulation between the scapula and the posterior ribs
Critical to shoulder motion – Scapulohumeral rhythm

Ligaments –

1) Sternoclavicular (SC) Sternum and the Clavicle
2) Coracoacromial (CA) Coracoid Process and the Acromian Process
3) Acromioclavicular (AC) Acromian Process and the Clavicle
4) Coracoclavicular (CC) Coracoid and the Clavicle
5) Coracohumeral (CH) Coracoid and the Humerus
6) Glenohumeral (GH) Glenoid Fossa and the Humerus
Superior
Middle
Inferior
7) Joint Capsule

MUSCLES –Produce dynamic motion and establishes stability at the shoulder

Motions:
Flexion and extension
Abduction and Adduction
Internal and External Rotation

3 Groups of Muscles

Group 1 – From the skeleton to the Humerus

• Latissimus Dorsi
• Pectoralis Major

Group 2 – Scapula to the Humerus

• Deltoid
• Teres Major
• Rotator Cuff – Adheres to the capsule and reinforces the structure
Supraspinatus
Infraspinatus
Teres Minor
Subscapularis
• Biceps
• Triceps

Group 3 Scapular Muscles – From the skeleton to the scapula – Provides dynamic stability to the shoulder

• Levator Scapula
• Trapezius
• Rhomboids
• Serratus Anterior

Bursae – Most Important Bursae is the Subacromial bursae

- Between the coracoacromial arch and the glenohumeral capsule
- Easily injured when the humerus is over the head
- Biceps Tendon, Supraspinatus tendon

Nerve Supply – Spinal Nerve Roots C5-T1
Creates the brachial Plexus

Functional Anatomy
The shoulder has a great deal of mobility
Stability is compromised
Instability leads to injury – often in overhead sports
Humeral head must stay relative to the Glenoid fossa
Dynamic stability from the rotator cuff maintains position of the Humerus

Dynamic Movement – The Glenohumeral joint in conjunctions with the AC, SC and the Scapulothoracitic joint creates the excessive motion.

Scapulohumeral Rhythm – Describes the movement of the scapula relative to the movement of the Humerus throughout a full range of abduction

- 0 – 30 degress – No scapular movement
- 30 - 90 degress – 2 humeral degrees = 1 scapular degree
- 90+ degrees – 1 humeral degree = 1 scapular degree

PREVENTING SHOULDER INJURIES

• Proper physical conditioning is of major importance in preventing many shoulder injuries
• Program should be develop around the entire body, if extreme activity is required at the shoulder, then extensive conditions must be used
• Proper warmup must be accomplished
• Instructed and drilled on how to fall properly on the shoulder
• Don’t catch on an outstretched arm
• Must be taught appropriate techniques for overhead activities

ASSESSMENT OF THE SHOULDER COMPLEX

History –
Must understand biomechanics of the shoulder in the activity
Acute vs chronic or overuse
Acute?? Force or blow
Numbness
Fatigue of muscle
Position of shoulder when pain occus
Movements that cause pain

Observation –
Shoulder tips level (Acromian Process)
Shoulder level (Muscle Spasm)
Clavicle equal
Biceps irregularities (Rupture?)
Thoracic Kyphosis (rolled shoulders)
Scapular movement
Winging scapula

Palpation

Anterior Side
SC Joint
Clavicle
AC Joint
Coracoid Process
Acromion Process
Humeral Head
Bicipital Groove
Deltoid (Ant & Middle)
Rotator Cuff Tendons
Subacromial space
Pect Major
Sternocleidomastoid
Bicpes
Glenohumeral Joint Capsule

Special Tests

Active and Passive ROM
Flexion = 180 degrees
Extension = 50 degrees
Abduction = 180 degrees
Adduction = 40 degrees
Int. Rotation = 90 degrees
Ext. Rotation = 90 degrees
Piano Key Test - AC joint sprain
Apprehension test - shoulder DX
Drop Arm Test – Supraspinatus
Empty Can Test – Supraspinatus
Impingement Test - Shoulder Impingement
Adson’s Test – Thoracic Outlet Syndrome

Shoulder Injuries (561)

Clavicle FX:
Commonly occur in the middle third of the bone and in young athletes usually are greenstick fx.

MOI:
One of the most common fractures in sports. Fractures result from a fall on the outstretched arm arm, a fall on the tip of the shoulder or direct blow to the clavicle.

S&S:
Supports arm on injured side and titles head toward that side to take pressure of clavicle. May have signs of obvious deformity, swelling, point tenderness, etc

Treatment:
Sling
X-ray
DR
Figure 8 brace for 6-8 weeks

Scapular FX (562)
Infrequent injury in sports. Well protected, by design and by muscles above and below

MOI:
Direct blow or impact then the force is transmitted through the Humerus to the scapula. Fractures can also happen to any process of the scapula

S&S:
Pain during shoulder movements and swelling along with point tenderness

Treatment:
Sling and x-ray
Sling for 3-4 weeks

Fractures to the Humerus (563)
Fractures can occur to the humeral shaft, proximal humerus and the head of the Humerus.

MOI:
Humeral Shaft: direct blow or fall on the arm.
Deformity is often seen as the bone fragments override each other as a result of the strong muscular pull.

Proximal Humerus:: Direct blow, dislocation or impact received by falling on the arm. Various parts of the Humerus may be involved, such as the anatomical neck, tuberosities or the surgical neck. Often mistaken for a shoulder DX. Greatest number of fractures at the surgical neck.
Epiphyseal Fractures (Growth plate): More common in the young athlete (10 and younger). Caused by a direct blow or indirect force traveling along the length of the Humerus.

S&S:
Difficult to recognize by visual inspection alone. Pain, inability to move the arm, swelling, point tenderness and the discoloration. Severe hemorrgaging or paralysis may occur.

Treatment:
Immediate care
Out 3-4 months
Cast, sling, reduction

Sternoclavicular Sprain (564)

MOI: relatively uncommon is sports, but may occur as a result from one of the various traumas effecting the shoulder girdle.
Medial end of the clavicle must be displaced normally up and forwards

S&S: Three grades
Grade 1: little pain and disability, with some point tenderness, but no deformity
Grade 2 displays a SX SC joint with visible deformity, pain , swelling, point tenderness and inability to abduct the shoulder
Grade 3: complete DX of the SC joint. Gross displacement. If displaced posteriorly, pressure may be placed on the blood vessels, esophagus, or trachea, cause a life and death situation.

Treatment: RICE
Sling
3-5 weeks

AC sprain (564)
AC joint is extremely vulnerable to sprains among active sports participants, especially in collision sports. Piano Key Test

MOI: direct impact to the tip of the shoulder, pushing the acromion process downward, or by an upward force exerted against the long axis of the humerus. Normally arm is adducted and partially flexed.

S&S: Three grades
Grade 1: AC sprain reflects point tenderness and discomfort during movement at the AC joint. No deformity, indicating only a mild stretching of the AC ligament.
Grade 2: Small tear or rupture of the AC ligament. Associated with a tear of the CC ligament. Small displacement of the clavicle vs the acromion. May require surgery.
Grade 3 Involves rupture of the AC and CC ligaments and dislocation of the clavicle. Also may have injured the CA ligament.
Treatment: Immediate care of the AC sprain. RICE
Sling
Possible Surgery for grade 2 and 3

Glenohumeral Joint Sprain

MOI: similar to that which produces DX of joint.
Forced Abduction
Often involves the Rotator Cuff Muscles (infraspinatus and teres minor)

S&S Complains of pain during arm movement, especially when MOI is reproduced. Decreased ROM.

Treatment:
RICE, ultrasound, cryotherapy range of motion exercises

Acute SX and DX of the Shoulder (567)
Account for up to 50% of all dislocations in the body. The extreme ROM creates an inherent instability in the joint.

Anterior most common, posterior 1-4%, inferior rare, superior never

SX:
MOI: excessive translation of the humeral head on the glenoid fossa. Forced horizontal abduction.

DX
MOI: direct impact to the posterior side of the shoulder or forced abduction, external rotation and extension.
Also may fall on an outstretched arm, or anterior blow for a posterior dx.

S&S: Shows a flattened deltoid contour. Palpation in the armpit reveals the humeral head is present. Athlete caries the affect arm in a slight abducted and externally rotated fashion and is unable to touch the opposite shoulder with the hand of the affected arm.

Treatment: reduction by a doctor
Sling for about 1-2 weeks
Strengthening

Recurrent Instability (Chronic SX and DX) (570)

After the initial injury a recurrent injury is very common, due to the disruption of the joint capsule. Most are going to be anterior problems.

Eventually will or may require surgery to fix.

Shoulder Impingement (571)

Involves mechanical compression of the supraspinatus tendon, the subacromial bursa, and the long head of the biceps tendon, all of which are located under the coracoacromial arch. The space under the clavicle and acromian is limited and can cause an irritation to occur to any of the structures.

Often associated with shoulder instability: Instability can cause a ‘sloppy” shoulder to occur, which directly causes the inflammation to occur of the structures in the subacromial space.

Force internal rotation and adduction is a good indicator for the injury.
May show some lack of strength and or numbness in the arm.

Rotator Cuff Tears (572)

Almost always are near the insertion of the muscle onto the greater tuberosity of the humerus.
Either what is called a partial thickness tear or full thickness tear.
Associated with an acute trauma, or impingement. Chronic overuse may also present.
Supraspinatus muscle most commonly injured.

Overhead activities will show a weakness in the ability to use the shoulder.
Lack of strength or function
Positive Empty can test or drop arm test

Treatment: restore proper mechanics, strength via JOBE exercises
May require surgery for more severe injuries

Shoulder Bursitis (574)

MOI: Chronic inflammation result from overuse or trauma
Develop a direct impact under the subarcromial arch
Most common is subacromial bursa.

S&S pain when trying to move the shoulder, especially abduction or with flexion, adduction and internal rotation. Point tenderness in the subacromial space. Positive Impingement tests.

Treatment:
RICE
NSAIDS
Electric modalities

Biceps Brachii Rupture (575)

MOI: Powerful concentric or eccentric contraction of the muscle. Normally rupture occurs near bicipital groove.
S&S: May show signs of obvious rupture, balled up in upper arm.
Weakness in elbow flexion

Treatment: refer to MD
May require Surgery

Throwing Mechanics:

Three phases:

Cocking
Acceleration
Follow-through (deceleration)