Anatomy Exam 1: Upper Limb 1

Gross Anatomy 1

Clavicle Ossification: Order

the clavicle is the first bone to ossify and the last to complete the process.

When does clavicle ossification begin?

5th/6th week

When does clavicle ossification complete?

20-25 years of age

What type of clavicle ossification occurs?

undergoes endochondral and intramembranous ossification

Where do clavicle fractures occur?

In the middle third of the clavicle

What structures are comprised of the surgical neck (Humeral fracture)?

Axillary Nerve and posterior Humeral circumflex artery

What structures are comprised of the mid-shaft (humeral fracture)?

radial nerve and deep brachial artery

What structures are comprised of the supracondylar (humeral fracture)?

Brachial artery and median nerve (anterior interosseus branch)

A.R.M.

Axillary Nerve

Radial Nerve

Median Nerve

Abduction/Adduction of the Glenohumeral

lateral/medial arm movement away from the body; in the coronal plane

Flexion/Extension of the glenohumeral

forward/upward vs backward/upward arm movement; sagittal plane

Medial/Lateral Rotation of the glenohumeral

Arm turned inward/outward in relation to the body; transverse plane

Circumduction of glenohumeral

circular movement of the arm at the shoulder joint; combines flexion, extension, adduction and abduction

Upward/Downward rotation of scapula

Rotational lateral/medial movement of the scapula; frontal plane

Protraction/Retraction of scapula

Scapular movement away/toward the spine

Elevation/Depression of scapula

superior/inferior translation of the scapula next to thoracic wall

Articulations of the sternoclavicular joint (SC)

proximal (sternal) end of clavicle and the clavicular notch of the manubrium (near sternum)

SC joint classification

Synovial joint; saddle joint

SC Joint movements

elevates/depresses; protracts/retracts; anterior/posterior rotation

The interclavicular ligament prevents:

Excessive depression of the clavicle

The sternoclavicular liigament prevents/resists:

anterior and posterior translation of the proximal clavicle

Costoclavicular ligament (rhomboid) is the:

primary stabilizer of the SC joint

The most frequent SC joint dislocation is an:

Anterior displacement (dislocation)

Articulation of the Acromioclavicular Joint

distal (acromial) end of the clavicle and the acromion process of the scapula

Joint classification of the AC joint

Synovial; plane joint

Movement of the AC Joint

Gliding allows scapular rotation (upward/downward)

Tilt (anterior/posterior)

rotate (internal/external) relative to the clavicle

The Acromioclavicular ligament is a:

Small ligament that provides horizontal stability

The coracoclavicular ligament is a:

an extrinsic ligament that provides much of the weight bearing support for the upper limb

consists of the trapezoid ligament and the conoid ligament

Division of the coracoclavicular ligament

Both the trapezoid ligament and the conoid ligament provide vertical stability

The coracoacromial ligament attaches:

from the coracoid process to the acromion process

prevent excessive superior displacement of the humeral head

coracoacromial arch is formed by:

the inferior aspects of the acromion and coracoid process and the coracoacromial ligament combined together.

provide a protective roof over the supraspinatus and long head of biceps brachii

The subacromial space is:

space between the humeral head ad the coracoacromial arch

The muscle protection of the coracoacromial arch consists of:

the supraspinatus and long head of biceps brachii

Prevention of the coracoacromial arch is:

superior displacement of the humeral head

Rockwood Classification of the AC Joint Type I:

Acromioclavicular ligament sprained;

ligaments are stretched, but still intact (no displacement)

Rockwood Classification of the AC Joint Type II:

Acromioclavicular ligament is torn and coracoclavicular ligament is sprained

Causes slight elevation of the clavicle

Rockwood Classification of the AC Joint Type III:

acromioclavicular ligament and coracoclavicular ligament are torn

Complete seperation and an obvious elevation of the clavicle

Impingement Syndrome

The tissues of the subacromial space become compressed during arm elevation

What muscles does impingement syndrome involve?

Supraspinatus

long head of biceps brachii

subacromial bursa

subdeltoid bursa

Articulations of the glenohumeral joint

Head of humerus and the glenoid cavity of the scapula

Classification of the GH Joint

Synovial Joint; Ball and socket joint

Movements of the GH Joint include:

Flexion/extension, abduction/adduction, medial/lateral rotation, and circumduction

what does the glenoid labrum do to the glenoid cavity?

it deepens and expands the cavity; the glenoid labrum is continuous with the tendon of long head of biceps brachii

Fibrous membrane of GH joint

is the outer membrane of the GH Joint capsule; it attaches to glenoic cavity outside of the glenoid labrum attachment

Coracohumeral ligament resists:

inferior translation of the humeral head and limits external rotation

Glenohumeral Ligaments (superior, middle and inferior)

reinforce the anterior capsule

resist anterior and inferior translation

Transverse Humeral Ligament

holds the tendons of biceps brachii muscle in the intertubercular sulcus

Synovial membrane of GH Joint

inner memrbane of GH Joint capsule

extends along the tendon of the long head of biceps brachii

Bursa associated with the GH joint capsule

subcutaneous acromial bursa

subacromial bursa and subdeltoid bursa

coracobrachial bursa

subcutaneous acromial bursa

reduces friction between the skin and the acromion process

subacromial bursa and subdeltoid bursa

reduces friction between supraspinatus and the coracoacromial arch/deltoid during shoulder abduction and rotation

coracobrachial bursa

subtendinois bursa of subscapularis

When the GH joint dislocates, what structures are affected?

posterior humeral circumflex artery

axillary nerve

Common location of GH Joint

Subcoracoid; Anterior direction

When a GH Joint occurs, what motions are affected?

abduction and external rotation

What’s a Bankart lesion?

a detachment or tear of the glenoid labrum from the glenoid cavity

What’s a Hill-Sachs lesion?

a compression fracture of the posterolateral humeral head with an anterior dislocation

SLAP Tear; what tissues does it involve?

Superior Labrum Anterior to Posterior Tear

the superior aspect of the glenoid labrum where the long head of biceps brachii tendon attaches

Frozen Shoulder

the loss of active and passive range of motion in all ranges of the GH Joint; often ideopathic (spontaneous, unknown cause)

What motions are limited with frozen shoulder?

External rotation is most common, along with abduction

How many carpal and metacarpals do we have?

8 carpals

5 metacarpals

Is it more dangerous to have a proximal or distal injury?

Proximal, because the distal regions are affected also.

The middle third of the clavicle is the most fractured region. Why?

It’s the thinnest portion and lacks strong ligament reinforcement

EX: a fall onto the lateral aspect of the shoulder, FOOSH - result in a direct blow to the clavicle

What humeral structures are affected on a surgical neck fracture?

The axillary nerve and posterior humeral circumflex artery

What humeral structures are affected on a mid-shaft fracture?

radial nerve and deep brachial artery

What humeral structures are affected on a supracondylar fracture?

brachial artery and median nerve (the interosseous branch)

What is ischemia?

a loss of oxygen in the blood

Which landmark of the scapula articulates with the humerus?

glenoid cavity (fossa)

are anterior or posterior sternoclavicular joint dislocations more common?

anterior SC joint dislocation are more common; more than 90% ore anterior dislocations caused by high force injury by forcing the proximal clavicle anteriorly

What are the causes/symptoms of impingement syndrome?

repetitive movements, overuse, or postural dysfunction

pain and decreased ROM w/overhead movements are symptoms of this

Which ligament is the primary stabilizer of the sternoclavicular joint?

costoclavicular ligament

Which ligament prevents superior displacement of the humeral head?

coracoacromial ligament

What is the glenoid labrum?

it’s a ring of fibrocartilage that deepens and expands the glenoid cavity

it’s continuous with the tendond of long head biceps brachii

Whats the difference between the fibrous membrane and the synovial membrane?

The fibrous membrane is superficial to the synovial membrane. It attaches to the glenoid cavity outside of the glenoid labrum attachment and LH of BB

attaches to the anatomical neck

The synovial membrane protrudes through apertures (opening) in the fibrous membrane to form some of the GH bursa

subcutaneous acromial bursa

reduces friction between the skin and the acromion process

subacromial bursa and subdeltoid bursa

often continuous with each other, they reduce friction between supraspinatus and the coracoacromial arch/deltoid during shoulder abduction and rotation

coracobrachial bursa (subcoracoid)

reduce friction between subscapularis and the tendons of coracobrachialis and SH of BB

usually continuous with the subtendinous bursa of subscapularis

A GH joint dislocation usually occurs during what ctions?

Abduction and extension (ABER)

GH joint dislocations are most commonly _______ and are located commonly in the _______.

anterior; subcoracoid

What arteries/nerves are compromised with a GH joint dislocation?

the axillary artery (posterior humeral circumflex artery) and the axillary nerve, along w/muscles that insert on the proximal humerus

What are causes of a SLAP tear?

FOOSH injury, repeitive overhead activituy, excessive traction of the arm

What are symptoms of a SLAP tear?

deep shoulder pain w/overhead motion

How is frozen shoulder treated?

usually with conservative car and/or corticosteroids

If those don’t work, surgery may be required

Which ligament provides stability to the long head of the BB as it passes through the intertubercular sulcus?

transverse humeral ligament

WHat’s the most common location of a shoulder dislocation?

subcoracoid