Exam II in Class Review

What nerve roots are primarily affected in Erb's palsy?

C5-C6

Which trunk of the brachial plexus is affected in Erb's palsy?

Upper (superior) trunk

What characteristic position is associated with Erb's palsy?

Waiter's tip deformity

What movements are commonly weak in Erb's palsy?

Shoulder abduction/external rotation and elbow flexion/supination

A baby experiences excessive separation of the head and shoulder during delivery. What brachial plexus injury could result?

Erb's palsy

A motorcycle rider lands forcefully on the shoulder and develops C5-C6 weakness. What condition should you suspect?

Erb's palsy

Which part of the brachial plexus is primarily affected in Klumpke's palsy?

Lower (inferior) trunk

Which nerve roots are primarily associated with Klumpke's palsy?

C8-T1

What area is especially affected by Klumpke's palsy?

Intrinsic muscles of the hand

What causes thoracic outlet syndrome?

Compression of neurovascular structures passing from the neck into the upper extremity

What symptoms may occur with thoracic outlet syndrome?

Pain, numbness, tingling, weakness, or vascular symptoms in the upper extremity

What is mallet finger?

Injury to the terminal extensor mechanism causing loss of active DIP extension

What joint remains flexed in mallet finger?

DIP joint

Mallet finger most commonly results from injury to what structure?

Terminal extensor tendon/slip

A ball strikes the tip of an extended finger and the client can no longer actively extend the DIP. What injury should you suspect?

Mallet finger

What is boutonnière deformity?

PIP flexion with DIP hyperextension

What structure is injured in boutonnière deformity?

Central slip of the extensor mechanism

A client has PIP flexion and DIP hyperextension. What deformity is present?

Boutonnière deformity

What is swan neck deformity?

PIP hyperextension with DIP flexion

A client has PIP hyperextension and DIP flexion. What deformity is present?

Swan neck deformity

How can you quickly distinguish boutonnière from swan neck?

Boutonnière = PIP flexion; Swan neck = PIP hyperextension

What nerve is commonly associated with claw hand?

Ulnar nerve

What position is characteristic of an ulnar claw?

MCP hyperextension with IP flexion, especially digits 4 and 5

What nerve is compressed in carpal tunnel syndrome?

Median nerve

Where does median nerve compression occur in carpal tunnel syndrome?

At the wrist within the carpal tunnel

What sensory area is commonly affected by carpal tunnel syndrome?

Thumb, index, middle, and radial half of the ring finger

What muscle group may become weak with severe carpal tunnel syndrome?

Thenar muscles

What is De Quervain's tenosynovitis?

Inflammation/irritation of the thumb tendons on the radial side of the wrist

Which two tendons are associated with De Quervain's?

Abductor pollicis longus and extensor pollicis brevis

Where would a client with De Quervain's typically report pain?

Radial/thumb side of the wrist

What motions commonly aggravate lateral epicondylitis?

Resisted wrist extension, gripping, and often forearm supination

What is lateral epicondylitis commonly called?

Tennis elbow

What is Dupuytren's contracture?

Thickening and shortening of the palmar fascia causing progressive finger flexion

What is trigger finger?

Catching or locking of a flexor tendon during finger movement

Which pulley is most commonly involved in trigger finger?

A1 pulley

What nerve controls most wrist and finger extension?

Radial nerve

What muscles does the radial nerve primarily supply in the arm and forearm?

Extensor muscles

What classic condition can occur with radial nerve paralysis?

Wrist drop

What causes wrist drop?

Weakness or paralysis of the wrist extensors from radial nerve injury

If a client cannot actively extend the wrist, which nerve should you suspect?

Radial nerve

Which nerve passes through the cubital tunnel?

Ulnar nerve

Which nerve passes behind the medial epicondyle of the humerus?

Ulnar nerve

Which nerve innervates biceps brachii and coracobrachialis?

Musculocutaneous nerve

What are the primary spinal roots of the musculocutaneous nerve?

C5-C7

Which major muscles are supplied by the musculocutaneous nerve?

Biceps brachii, brachialis, and coracobrachialis

What is the main motor function associated with the musculocutaneous nerve?

Elbow flexion

Which nerve is especially important for most intrinsic hand muscles?

Ulnar nerve

Which nerve innervates the dorsal interossei?

Ulnar nerve

Which nerve innervates the palmar interossei?

Ulnar nerve

What does PAD mean?

Palmar interossei ADduct the fingers

What does DAB mean?

Dorsal interossei ABduct the fingers

A client cannot spread the fingers apart. What muscles are likely weak?

Dorsal interossei

A client cannot bring the fingers together. What muscles are likely weak?

Palmar interossei

What nerve would you suspect if both finger abduction and adduction are weak?

Ulnar nerve

What are the spinal roots of the brachial plexus?

C5-T1

What is the order of the major portions of the brachial plexus?

Roots → Trunks → Divisions → Cords → Branches

Which brachial plexus structure comes immediately before the divisions?

Trunks

Which roots form the superior trunk?

C5-C6

Which root forms the middle trunk?

C7

Which roots form the inferior trunk?

C8-T1

Which nerve arises directly from the superior trunk?

Suprascapular nerve

Which two nerves arise from the roots of the brachial plexus?

Dorsal scapular and long thoracic nerves

Which terminal nerves arise from the posterior cord?

Axillary and radial nerves

Which terminal nerve arises from the medial cord?

Ulnar nerve

The median nerve receives contributions from which cords?

Lateral and medial cords

Which cord is posterior to the axillary artery?

Posterior cord

Which nerves arise proximally from the posterior cord?

Upper subscapular, thoracodorsal, and lower subscapular nerves

What nerve innervates latissimus dorsi?

Thoracodorsal nerve

What nerve innervates the deltoid?

Axillary nerve

What movement would likely be weak with axillary nerve palsy?

Shoulder abduction

What nerve is at risk with a surgical neck fracture of the humerus?

Axillary nerve

Is the brachial plexus the primary source of motor innervation to the upper limb?

Yes

What nerve primarily supplies the flexor compartment of the arm?

Musculocutaneous nerve

What nerve primarily supplies the extensor compartments of the arm and forearm?

Radial nerve

What is the best artery for taking a pulse at the wrist?

Radial artery

Where is the radial artery palpated for a wrist pulse?

Thumb/radial side of the wrist

What is the bony prominence forming the tip of the elbow?

Olecranon

What muscle attaches to the olecranon?

Triceps brachii

What muscle attaches to the radial tuberosity?

Biceps brachii

What muscle attaches to the ulnar tuberosity?

Brachialis

Which carpal bone articulates directly with the radius on the thumb side?

Scaphoid

Which carpal bone is commonly fractured after a FOOSH?

Scaphoid

What does FOOSH stand for?

Fall On an Outstretched Hand

After a FOOSH, a client has pain near the anatomical snuffbox. What fracture should you suspect?

Scaphoid fracture

What is the primary action of flexor digitorum profundus at the fingers?

Flexion of the DIP joints

What is the primary action of flexor digitorum superficialis at the fingers?

Flexion of the PIP joints

Which extensor structure primarily extends the PIP joint?

Central slip

Which extensor structure primarily extends the DIP joint?

Terminal tendon/slip

Damage to the central slip can lead to what deformity?

Boutonnière deformity

Damage to the terminal extensor tendon can lead to what condition?

Mallet finger

What bursa reduces friction beneath the acromion?

Subacromial bursa

What commonly aggravates an inflamed olecranon bursa?

Leaning directly on the elbow

What is the general function of a bursa?

Reduce friction between moving tissues

What movements occur at the radiocarpal joint?

Flexion, extension, radial deviation, and ulnar deviation

What movements occur at the radioulnar joints?

Pronation and supination

What movements occur at the elbow?

Flexion and extension

What movements occur at the MCP joints of digits 2-5?

Flexion, extension, abduction, and adduction

What movements occur at the PIP and DIP joints?

Flexion and extension

Which forearm bone rotates around the other during pronation and supination?

Radius rotates around the ulna

During pronation, what happens to the radius and ulna?

The radius crosses over the ulna