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PassPMR - 04 Electrodiagnostic Medicine > 4 - Upper Extremities Mononeuropathies > Flashcards

4 - Upper Extremities Mononeuropathies Flashcards

1
Q

Mention the Shoulder Stabilizers ๐Ÿ”‘๐Ÿ”‘ Dr. Jamal

A

DYNAMIC STABELIZER

  1. Rotator cuff muscles
  2. Deltoid
  3. Scapular stabilizers (e.g., trapezius, serratus anterior)
  4. Long head of the biceps tendon
  5. Teres major
  6. Latissimus dorsi

STATIC STABELIZER

  1. Glenoid (shallow articular surface located on the lateral angle of the scapula)
  2. Labrum (fibrocartilaginous tissue within the glenoid cavity)
  3. Shoulder capsule (ligaments connect the humerus (the upper arm bone) to the glenoid (the shoulderโ€™s socket) and stabilize the joint)
  4. Glenohumeral ligament (three ligaments on the anterior side of the glenohumeral joint)

Cuccurollo 4th Edition Chapter 4 MSK pg154

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2
Q

Medial vs Lateral Winging ๐Ÿ”‘๐Ÿ”‘ EXAM

A

Cuccurollo 4th Edition Chapter 5 EDX pg407

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3
Q

Root and Branch of Long Thoracic Nerve, EDX for shoulder winging & Treatment

A

๐Ÿ’ก C5, C6 and C7 spinal nerve root โ†’ Long Thoracic Nerve

NCS of Motor Nerve

  • SNAP: Not available
  • CMAP: Abnormal

EMG

  • Abnormal activity
    • Serratus anterior with a long thoracic nerve injury
    • Trapezius and SCM with spinal accessory nerve injury

Treatment of serratus anterior injury/injury to the long thoracic nerve

  1. Acute stage, pain reduction and ROM exercise
  2. Intermediate stage, passive stretching of the rhomboids, levator scapulae, and pectoralis minor
  3. Late stage, strengthening exercise of all shoulder girdle muscles, including the trapezius.
  4. Surgical repair with a dynamic muscle transfer in case of failed conservative treatment

Treatment of trapezius palsy/injury to the spinal accessory nerve

  • Strengthen adjacent muscle groups, including rhomboids and levator scapulae.

Cuccurollo 4th Edition Chapter 5 EDX pg407

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4
Q

Describe the difference between a long thoracic nerve palsy and a C5โ€“C6 radiculopathy ๐Ÿ”‘๐Ÿ”‘REVIEW

A

Long thoracic nerve palsy

Causes winging of the scapula with the arms outstretched because of weakness of the serratus anterior muscle.

C5โ€“C6 radiculopathy

Shoulder and arm muscles (e.g., deltoid, biceps, supraspinatus) will remain normal.

Neurology Secrets 6th Edition Chapter 32 EDX pg472

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5
Q

If pt. cannot do abduction from 0-15; what nerve affected?๐Ÿ”‘๐Ÿ”‘ EXAM

A

Suprascapular nerve, supraspinatous muscle

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6
Q

Patient with right scapular fracture, now presents with difficulty with arm abduction initiation but full active range of motion. On examination normal sensory only weakness with ER and Abduction, no sensory findings.๐Ÿ”‘๐Ÿ”‘ EXAM

What muscles are affected?

What nerve is affected?

On EMG what location for the lesion is important to rule out.

A

Muscle

  • Supraspinatous (Initial abduction)
  • Infraspinatus (External rotation)

Nerve

  • Suprascapular nerve

EMG

  • Infraspinatous to rule out lesion in supascapular notch - ligament

My Answer

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7
Q

Origin of Suprascapular nerve

List 4 causes of suprascapular nerve palsy

EDX result of supracapular nerve entrapment

A

๐Ÿ’ก C5 and C6 spinal nerve roots โ†’ upper trunk โ†’ suprascapular nerve

Coarse

It runs through the suprascapular notch, which is covered by the transverse scapular ligament and branches to innervate the supraspinatus. The nerve then wraps around the spinoglenoid notch to innervate the infraspinatus

Causes

  1. Sports with repetitive overhead throwing/hitting volleyball
  2. Neuralgic amyotrophy (C5-C6)
    1. Spinal accessory nerve
    2. Axillary nerve
    3. Suprascapular nerve
    4. Long thoracic nerve
    5. Anterior interosseus nerve [AIN]
  3. Trauma like penetration injury
  4. Traction like stinger, Erbโ€™s Palsy or rotator cuff tear
  5. Compression like entrapment or cyct or hematoms

Clinical Presentation

  1. Weakness in abduction (SS)
  2. External rotation (IS)

NCS

  • SNAP not available
  • CMAP: Abnormal

EMG:

  • Abnormal activity in both SS and IS muscles (entrapment at suprascapular notch)
  • Abnormal activity in IS only (entrapment is at the spinoglenoid notch)

Cuccurollo 4th Edition Chapter 5 EDX pg405-406

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8
Q

How is a suprascapular nerve lesion differentiated from a C5โ€“C6 radiculopathy?

A

Suprascapular nerve lesion

  • Preservation of the deltoid, biceps, and rhomboid muscles
  • Abnormalities in the supraspinatus and infraspinatus muscles

A rotator cuff tear will show normal EMG of all the shoulder muscles

Neurology Secrets 6th Edition Chapter 32 EDX pg472

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9
Q

Devision of axillary nerve 3 marks

A

1- Anterior Branch

Supply Middle and anterior deltoid

2- Posterior Branch

Supplies Teres minor & Posterior deltoid

3- Superior lateral brachial cutaneous nerve (axillary sensory nerve)

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10
Q

Root and Coarse & Branches of Axillary nerve 4 marks

A

๐Ÿ’ก Teres major is supplied by Lower subscapular nerve (C5-C7) which branches from posterior cord BEFORE axillary nerve.

Root

  • Upper trunk โ†’ Posterior divisions & cord โ†’ Axillary n. (C5-6)

Branch

  1. Deltoid
  2. Teres minor
  3. Superior lateral cutaneous n. of the arm

Cuccurollo 4th Eiditon Chapter 5 EDX pg404-405

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11
Q

Axillary nerve palsy Etiology, PEx & EDx.

Axillary nerve injury Presentation. 4 marks ๐Ÿ”‘๐Ÿ”‘

A

Etiology

  • Traction or compression from a shoulder dislocation
  • Humeral head fracture
  • Improper axillary crutch use.

Clinical presentation

  • Weakness of shoulder flexion
  • Weakness of shoulder abduction (deltoid weakness)
  • Weakness of shoulder external rotation (teres minor weakness).
  • Abnormal sensation of the lateral shoulder (lat cut n. of arm)

NCS:

  • SNAP not available
  • CMAP: Abnormal

EMG:

  • Abnormal activity in the deltoid & teres minor.

Cuccurollo 4th Edition Chapter 5 EDX pg405

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12
Q

Radial Nerve Origin & Coarse ๐Ÿ”‘๐Ÿ”‘ Motor and sensory branches.

A

ROOT

  • C5-T1 โ†’ upper, middle, and lower trunks โ†’ posterior division & cord โ†’ radial n.

COURSE

  • Posterior to the axillary artery goes in between triceps.
  • Long and medial heads of the triceps muscle toward the spiral groove
  • Distally between the brachioradialis and brachialis
  • Terminate in forearm as motor (PIN) and sensory (superficial) branch

ARM

  • Above Spiral Groove โ†’ Muscles & Sensation Above Elbow
    1. Triceps brachii
    2. Anconeus
    3. Posterior cutaneous nerve of arm
    4. Lower lateral cutaneous nerve of arm
  • Below Spiral Groove โ†’ Two Radialis & Sensation Below Elbow
    1. Brachioradialis (BR)
    2. Extensor Carpi Radialis Longus (ECR L)
    3. Posterior cutaneous nerve of the forearm

ELBOW

  1. Superficial radial sensory nerve
  2. Posterior Interosseus Nerve (PIN) ุนุตุจ ุงู„ู…ุดุงุจูƒ
    - Supinator
    - Extensor Wrist Compartment ๐Ÿ”‘๐Ÿ”‘ EXAM Q

1st : Abductor pollicis longus (APL) + Extensor pollicis brevis (EPB)

2nd: Extensor carpi radialis brevis (ECR-B)
3rd: Extensor pollicis longus (EPL)
4th: Extensor digitorum communis (EDC) + Extensor indicis proprius (EIP)
5th: Extensor digiti minimi (EDM)
6th: Extensor carpi ulnaris (ECU)

Cuccurollo 4th Edition Chapter 5 EDX pg400-401

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13
Q

When to consider root injury in case of radial n. injury? 4 marks

A

๐Ÿ’ก In any EDX question, think neuro examination + EDX study result

Sensory

  • Dermatomal sensory loss rather than peripheral nerve distribution

Motor

  • Involvement of median or ulnar innervated C7 and C8 muscles

NCS

  • Normal sensory study (SNAP)

EMG

  • Involvement of cervical paraspinals
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14
Q

When to consider posterior cord injury or C7-8 radiculopathy in case of radial n. injury?

A

Posterior Cord (Plexopathy)

  • Sensory loss around the deltoid muscle and upper arm.
  • Weakness of the deltoid muscle +/- subscapular muscles

C7-8 Radiculopathy

  • Involvement median (C5-T1) or ulnar n. (C8-T1)
  • Involvement of cervical paraspinals (Neck pain)

Neurology Secrets 6th Edition Chapter 32 pg 472-473

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15
Q

What is the key muscle in differentiating a radial nerve palsy from a C7 radiculopathy? ๐Ÿ”‘๐Ÿ”‘

A

Flexor carpi radialis is a C7 muscle but is innervated by the median nerve.

Neurology Secrets 6th Edition Chapter 32 EDX pg472

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16
Q

How is a radial nerve palsy differentiated from a brachial plexus posterior cord lesion?

A

Lesion in the posterior cord of the brachial plexus, abnormal both

  1. Deltoid muscle (axillary nerve)
  2. Radial-innervated muscles

Radial nerve palsy

  1. Spared Deltoid muscle (axillary nerve)
  2. Affected Radial-innervated muscles

Neurology Secrets 6th Edition Chapter 32 EDX pg472

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17
Q

List 8 muscles innervated by Radial nerve ๐Ÿ”‘๐Ÿ”‘

List 3 Muscles functioning at the wrist joint which are innervated by radial n. ๐Ÿ”‘

List 4 Sensory branches of radial nerve ๐Ÿ”‘

A

Above the Elbow โ€œExtensionโ€

  1. Triceps
  2. Anconeus

At the Elbow โ€œFlexionโ€

  1. Brachioradialis

Below the Elbow โ€œPIN, Extensionโ€

  1. Supinator
  2. Abd. poll. longus
  3. Ext. poll. longus & brevis
  4. ECR longus & brevis
  5. Finger extensors
  6. ECU

Wrist Joint ู…ุดุงุจูƒ

  1. Extensor carpi radialis brevis (ECR-B)
  2. Extensor carpi ulnaris (ECU)
  3. Supinator

Sensory

  1. Posterior cutaneous n. of the arm
  2. Lower Lateral cutaneous n. of the arm
  3. Posterior cutaneous n. of the forearm
  4. Superficial radial sensory n.
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18
Q

Crutch Palsy: Injury - PEx - EDx. ๐Ÿ”‘๐Ÿ”‘

A

Injury

  • Posterior cord of the brachial plexus, most commonly affecting the radial nerve.

Clinical presentation

  • Weakness of deltoid muscles
  • Weakness in all radial nerve innervated muscles, including the triceps brachii.
  • Sensation will be decreased over the posterior arm, forearm and hands.
  • Diminished triceps reflex (LMN)

EDXs

Posterior cords Injury

  • Abnormal SNAPs and CMAPs of radial, axillary, and/or suprascapular nerves.
  • Abnormal EMG activity in corresponding muscles

Isolated Radial Injury

  • Abnormal radial SNAP and CMAPs
  • Abnormal EMG activity in all radial nerve innervated muscles

Managment

๐Ÿ’ก External compression typically causes neurapraxia that recovers within 2 months.

  1. Remove compression: Discontinuing crutch use
  2. Static cock up splint or dynamic splinting
  3. No recovery within 8 to 10 weeks, surgical exploration is indicated
  4. No return of function after 1 year, refer for tendon transfer

Cuccurollo 4th Edition Chapter 5 EDX pg401

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19
Q

Radial entrapment at the upper arm vs elbow. How to distinguish in clinical examination. ๐Ÿ”‘๐Ÿ”‘ Hint: it neuro examination (sensory - motor - reflexes)

A

Above Spiral Groove โ†’ Muscles & Sensation Above Elbow

  1. Triceps brachii
  2. Anconeus
  3. Posterior cutaneous nerve of arm
  4. Lower lateral cutaneous nerve of arm

Below Spiral Groove โ†’ Two Radialis & Sensation Below Elbow

  1. Brachioradialis (BR)
  2. Extensor Carpi Radialis Longus & Brevis (ECR L & B)
  3. Posterior cutaneous nerve of the forearm

Elbow

  1. PIN
  2. Supinator
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20
Q

Radial entrapment at the upper arm vs elbow. How to distinguish in clinical examination. ๐Ÿ”‘๐Ÿ”‘ Saturday night palsy Etiology, PEx, EDx & Treatment.

A

Location

  • Radial nerve injury at the spiral groove, compression, trauma or humeral fractures.

Etiology

  1. Humeral fractures
  2. Compression: Saturday night palsy or honeymoonerโ€™s palsy.
  3. IM injection
  4. Iatrogenic injury (upper limb surgery)

Sensory

  • Sensory deficits dorsal aspect of the hand and posterior forearm
  • Intact sensation of posterior and lateral arm

Motor

  • Preservation of elbow extension (triceps, anconeus)
  • Weakness of elbow flexion (BR)
  • Weakness of PIN muscles
    1. Weakness of supination (supinator)
    2. Wrist drop (ECR-L, ECR-B, ECU weakness)
    3. Weak finger extension (EDC weakness)

Reflexes

  • Diminished brachioradialis reflex.
  • Spared triceps and biceps reflexes

NCS

  • Abnormal radial SNAPs and CMAP
  • Normal triceps study

EMG

  • Abnormal activity in all radial nerve innervated muscles below the spiral groove
  • Normal triceps study

Cuccurollo 4th Edition Chapter 5 EDX pg401

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21
Q

Posterior Interosseous Nerve, Mention the motor and sensory supply. ๐Ÿ”‘๐Ÿ”‘ EXAM 2020

A

Motor ู…ุดุงุจูƒ

  1. Supinator muscle
  2. Extensor compartment of the wrist

Sensory

  • Dorsal wrist joint capusle (proprioception)
  • No cutaneous innervation

Last muscle to recover is the extensor indicis proprius.

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22
Q

List 5 radial muscles that are not innervated by PIN. ๐Ÿ”‘๐Ÿ”‘ Patient with elbow fracture, mention which radial muscles that are spared? ๐Ÿ”‘๐Ÿ”‘

A
  1. Triceps
  2. Anconeus
  3. Brachioradialis (BR)
  4. Extensor carpi radialis longus (ECR-L)
  5. Extensor carpi radialis brevis (ECR-B)
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23
Q

Radial tunnel syndrome (Brachial Family) Etiology, PEx & EDx.

Supinator Syndrome Etiology, PEx & EDx.

A

RADIAL TUNNEL SYNDROME

Etiology

  • Entrapped radial n. between the brachialis and BR in the radial tunnel in the elbow.

PEx

  • Lateral proximal forearm pain that worsens with activity
  • approximately 3 to 4 cm distal to the lateral epicondyle.
  • Can mimic lateral epicondylitis.

EDX

  • NCS and needle EMG studies are typically normal

SUPINATOR SYNDROME (Lesion of the PIN)

Causes

  1. Compression of the nerve at the Arcade of Frohse
  2. Lipoma, ganglion cyst, synovitis from RA
  3. Monteggia fracture: fall on an outstretched hand with the forearm in pronation.

PEx (Pure Motor Syndrome, PIN is just like AIN of median nerve)

  1. Intact triceps
  2. Intact brachioradialis
  3. Intact radial deviation (ECR gets innervated before supinator muscle)
  4. +/- Supinator
  5. Wrist and finger drop (finger extensors and ECU)
  6. Intact sensory branches on arm & forearm

NCS

  • Normal sensory radial nerve SNAP (itโ€™s a motor syndrome)
  • Abnormal radial CMAP motor study for PIN innervated muscles.

EMG

  • Abnormal activity in the muscles innervated by the PIN

Cuccurollo 4th Edition Chapter 5 EDX pg402

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24
Q

How to different between lateral epicondylitis and radial tunnel syndrome? ๐Ÿ”‘๐Ÿ”‘

A

RADIAL TUNNEL SYNDROME

  1. Resisted extension of the third digit during elbow extension
  2. Resisted supination
  3. Palpation of the radial tunnel

LATERAL EPICONDYLITIS (TENNIS ELBOW)

  1. Palpation directly on the lateral epicondyle
  2. Cozenโ€™s test: Pain on resisted wrist extension
  3. Less pain on resisted supination

Cuccurollo 4th Edition Chapter 5 EDX pg402

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25
Q

Wartenbergโ€™s (Watch-enburg) Syndrome Etiology, PEx & EDx.

A

Etiology

  • Superficial radial nerve injury at the wrist
  • Seen in tight wristwatch, tight handcuffs, peripheral IV placement

Clinical presentation

  • Pure sensory syndrome with no muscle involvement.
  • Pure sensory syndrome with no muscle involvement
  • Exacerbated with palmar and ulnar wrist flexion or forced pronation.

EDX

  • NCS: Abnormal radial nerve SNAP but normal CMAP
  • EMG: Normal

Cuccurollo 4th Edition Chapter 5 EDX pg403

26
Q

List 4 Differential Diagnosis of a Wrist Drop ๐Ÿ”‘

Wrist drop: what are possible anatomic localizations? ๐Ÿ”‘๐Ÿ”‘

A

Differential Diagnosis of a Wrist Drop

  1. Mononeuropathy: PIN, radial nerve
  2. Radiculopathy: C6 or C7
  3. Diffuse polyneuropathy: Lead
  4. Plexopathy: Posterior cord, upper trunk, middle trunk
  5. Central: SCI/TBI/CVA, etc.

Cuccurollo 4th Edition Chapter 5 EDX pg402

Shapiro Chapter 24 Box 24.1

Other causes based on case, just to think in bigger picture:

  1. NMJ disorder
  2. Myopathies
27
Q

Musculocutaneous Nerve: Origin and Branches of Musculocutaneous nerve.

Musculocutaneous nerve palsy Etiology, PEx & EDx

List 4 branches of Musculocutaneous nerve ๐Ÿ”‘๐Ÿ”‘

A

ORIGIN

  • Upper trunk โ†’ Anterior division โ†’ lateral cord โ†’ Musculocutaneous branch (C5-7)

BRANCHES

  1. Coracobrachialis
  2. Biceps brachii
  3. Brachialis (also radial n.)
  4. Lateral cutaneous nerve of the forearm

MUSCULOSURANEOUS PALSY

  1. Trauma: proximal humeral fractures, shoulder dislocation, gunshot wounds
  2. Compression
  3. Phlebotomy

PEx

  1. Elbow flexion weakness (Biceps, Brachialis)
  2. Coracobrachialis is typically spared
  3. Abnormal sensation over the lateral forearm.

NCS

  • Abnormal SNAP in the lateral cutaneous nerve of the forearm
  • Abnormal CMAP to the biceps brachii

EMG

  • Abnormal activity in the brachialis and biceps brachii

Cuccurollo 4th Edition Chapter 5 EDX pg404

28
Q

Median Nerve: Origin - Course

Motor & sensory branches of medial nerve. (11) ๐Ÿ”‘๐Ÿ”‘

Median innervated muscles in order, proximal to distal ๐Ÿ”‘๐Ÿ”‘

A

ORIGIN

  • C5โ€“T1 roots โ†’ upper, middle, and lower trunks โ†’ medial and lateral cords โ†’ median n.

COURSE

  • Medial to the axillary artery, It continues down the humerus.
  • Ligament Of Struthers (LOS) at the medial epicondyle of the humerus.

FOREARM (4+1)

  1. Pronator teres (PT)
  2. FCR
  3. Palmaris longus
  4. Flexor digitorum superficialis (FDS)
  5. Palmar cutaneous (thenar eminence)

ANTERIOR INTEROSSEOUS NERVE (3)

  1. Flexor pollicis longus (FPL)
  2. Flexor digitorum profundus (1, 2)
  3. Pronator quadratus (PQ)

HAND (LOAF)

  1. Lumbricals (1, 2)
  2. Opponens pollicis
  3. Abductor pollicis brevis
  4. Flexor pollicis brevis 1/2
  5. Digital cutaneous n. for 3 1/2 fingers

SENSATION

  • Sensation of the hand is lost in proximal lesions of median nerve, i.e. at the elbow
  • Digital sensation will be lost in proximal lesions like carpal tunnel syndrome.
29
Q

What are the common sites of median nerve compression should be considered in the deferential diagnosis of CTS? ๐Ÿ”‘๐Ÿ”‘

A
  1. Supracondylar ligament of Struthers
  2. Lacertus Fibrosis (Bicipital aponeurosis)
  3. Two heads of pronator teres
  4. Anterior interosseos branch (AIN)
  5. Carpal Tunnel

PMR Secrets 3rd Edition Chapter 18 Neuropathy pg156 Q19

30
Q

A 40-year-old lady who works as a secretary, is complaining of numbness involving her right radial 3 and half digits that wakes her up at night. ๐Ÿ”‘๐Ÿ”‘

1) Name the nerve involved in this condition.
2) Name the root(s) origin of that nerve.

Female with radial aspect numbness, relived with shaking, increase at night.

1) Diagnosis
2) 3 Special Test
3) Other causes for her diagnosis ๐Ÿ”‘๐Ÿ”‘

A

Diagnosis

  • Median nerve
  • Carpal Carpal Tunnel Syndrom
  • C5-T1

Tests

  1. Phalen
  2. Reverse Phalen
  3. Compression / Torniquete Test
  4. Tinelโ€™s Sign

Causes

  1. Pregnancy (20%).
  2. Rheumatoid arthritis (any inflammatory arthritis).
  3. Fracture
  4. Acromegaly.
  5. Glucose (diabetes).
  6. Mechanical (overuse, occupational).
  7. Amyloid.
  8. Thyroid (myxedema)
  9. Infection (TB, fungal)
  10. Crystals (gout, pseudogout).
  11. Renal Failure

Cucurollo & Rheumatology Secrets

31
Q

Ligament of Struthers & Bicipital aponeurosis (Lacertus fibrosus) Etiology, PEx & EDX.

A

Ligament of Struthers

The nerve becomes entrapped with the brachial artery under the ligament.

Bicipital aponeurosis

Thickening of the antebrachial fascia compressing median nerve or arterial blood gas or venipuncture injury.

Presentation

  1. Motor weakness
    • Weakness in grip strength (FDP and FDS weakness)
    • Wrist flexion (FCR weakness).
    • Active benediction sign (proximal median nerve injury)
  2. Sensory loss
    • Dull, achy sensation can occur in the distal forearm.
  3. Brachial pulse is possibly diminished.

NCS

  • Abnormal median SNAP and CMAP

EMG

  • Abnormal in median nerve-innervated muscles, including the PT

Cuccurollo 4th Edition Chapter 5 EDX pg391

32
Q

Pronator teres syndrome Compression sites, PEx & EDX.

A

Compression site

  1. Two heads of the pronator teres (PT)
  2. Biceps aponeurosis.
  3. Sublimis Bridge: fascial band from the flexor digitorum superficialis (FDS)

Presentation

  • Pronator Teres (PT) muscle is usually spared, as it receives its innervation before it is pierced by the nerve.
  • Pain exacerbated by forceful pronation (PT) or finger flexion (FDS).
  • Forearm and hand muscles may become easily fatigued.
  • Patients present with pain and paresthesias in the first three fingers of the hand

NCS

  • Abnormal median nerve SNAPs and CMAPs

EMG

  • Abnormal activity in all median nerve innervated muscles EXCEPT the PT

Cuccurollo 4th Edition Chapter 5 EDX pg391

33
Q

AIN palsy Etiology, PEx & EDX.

A

Etiology:

  1. Repetitive forearm flexion or pronation
  2. Elbow or forearm fractures
  3. Venipuncture or penetrating injuries
  4. Lacerations, or compression.
  5. Brachial neuritis.

Presentation

  1. Motor: Positive (abnormal) โ€œOKโ€ sign and inability to form a fist (FPL, PQ, and FDP 1, 2)
  2. Sensory: volar branches to the wrist joint.

NCS

  • Sensory Study (SNAP): Normal median nerve
  • Motor Study (CMAP): Abnormal to the AIN muscles.

EMG

  • Abnormal to the AIN muscles.

๐Ÿ’ก AIN is like PIN, both are motor nerves resulting in normal sensory study.

Treatment

  • Surgical exploration and decompression should be delayed unless there is no recovery after 12 months.

Cuccurollo 4th Edition Chapter 5 EDX pg392

34
Q

Content of carpel tunnel & Mention the boards. 10 marks ๐Ÿ”‘๐Ÿ”‘

A

Content

  1. Flexor digitorum superficialis tendons (4)
  2. Flexor digitorum profundus tendons (4)
  3. Flexor pollicis longus tendon (1)
  4. Median nerve (1)

Boarders

  • Transverse carpal ligament & Carpal arch bones

Cuccurollo 4th Edition Chapter 5 EDX pg393 Figure 5-88

35
Q

List 4 Risk Factors & 4 Symptoms for CTS ๐Ÿ”‘๐Ÿ”‘

A

Risk Factors

  1. Idiopathic process (most common)
  2. Increased canal volume โ†’ thyroid disease, congestive heart failure (CHF), renal failure, mass (tumor, hematoma), and pregnancy
  3. Decreased canal volume โ†’ fracture, arthritis, and rheumatoid tenosynovitis.
  4. Double crush syndrome โ†’ diabetes mellitus, cervical radiculopathy, and TOS.
  5. Occupational exposures
  6. Female, Menopause

Symptoms

  1. Numbness of 3 1/2 fingers
  2. Thenar eminence will be spared as the palmar cutaneous branch comes off before the carpal tunnel (hyposthesia in pronator teres syndrom)
  3. Pain which can radiates to forearm (DDx cervical radiculopathy, epicondylitis)
  4. Muscle weakness in โ€œLOAFโ€ muscles (opening jars, buttoning, or dropping objects.)
  5. Autonomic symptoms (tight or swollen feeling, temperature changes)

Cuccurollo 4th Edition Chapter 5 EDX pg393

36
Q

Patient with numbness and pain in his thumb, index and middle finger. Give 6 DDx other than CTS. ๐Ÿ”‘

A

Spinal Cord

  1. C6 or C7 radiculopathy
  2. Cervical cord compression
  3. Myelopathy
  4. Syringomyelia

Brachial Plexus

  1. Brachial Plexopathy โ†’ any trunk or mediolateral cord
  2. Thoraric outlet syndrom

Mononeuropathy

  1. Proximal median nerve injury (pronator or anterior interosseous syndrome)
  2. Martin-Gruber anastomosis (MGA)

MSK

  1. Tenosynovitis (De Quervainโ€™s)
  2. Wrist tendonitis (overuse)
  3. Osteoarthritis (Carpometacarpal)
  4. Keinbockโ€™s Disease (AVN lunate necrosis)

PMR Secrets 3rd Edition Chapter 18 Neuropathy pg155 Box 18-4

37
Q

Mention which branches of median nerve that is not affected (spared) in CTS. 2 marks ๐Ÿ”‘๐Ÿ”‘

A

๐Ÿ’ก CTS = LOAF + Digit cutaneous nerve

1- Spared sensation of thenar eminence

Palmar cutaneous n. branches before the carpal tunnel

2- Spared AIN muscles

AIN branches before the carpal tunnel

3- Spared Forearm muscles

FCR, Palmaris longus and FDS

38
Q

Patient with hand numbness suspecting CTS.

During your examination, what findings suggest other diagnosis rather than CTS?

What clinical findings suggest other pathology of his condition?

Findings make you suspect other diagnosis, not just CTS?

A

1- Tenderness

tendonitis, tenosynovitis

2- Involvement of more than LOAF muscles

  1. Weakness in other median innervated muscles โ†’ AIN, PTS
  2. Weakness of ulnar or radial innervated muscles (root or plexus)

3- Reflexes

Asymmetry of muscle stretch reflexes or prominent neck pain. (root, UMN)

39
Q

What are the degrees of CTS ๐Ÿ”‘๐Ÿ”‘

A

Memory Aid

Starts with sensory dysthesia at first, abnormal SNAP (demyelination)

Progress to weakness and atrophy of thenar (LOAF) muscles, abnormal CMAP (axonal)

Cuccurollo 4th Edition Chapter 5 EDX pg393

40
Q

List 5 Provocative Tests for CTS ๐Ÿ”‘๐Ÿ”‘

A

1- Tinelโ€™s sign

Percussion of the median nerve at the wrist

2- Phalenโ€™s test

Hold the wrist at 90 degree flexion for approximately 1 minute

3- Reverse Phalenโ€™s test

Hold the wrist at 90 degree of extension for approximately 1 minute

4- Tourniquet test

Inflated BP cuff reproduction of symptoms at 1 minute

5- Carpal compression test

Hold thumb compression over the tunnel for 30 seconds

Cuccurollo 4th Edition Chapter 5 EDX pg394

41
Q

List 4 Ultrasound Findings in Carpal Tunnel Syndrome ๐Ÿ”‘

A
  1. Flattening & enlargement of the median nerve (inflamed and compressed)
  2. Decreased median nerve mobility with wrist flexion.
  3. Bowing of the flexor retinaculum (swelling & edema)
  4. Increased vascularity (Inflammation)
42
Q

Role of EMG in CTS๐Ÿ”‘๐Ÿ”‘

A

๐Ÿ’ก Severe cases present with wasted hand and weakness due to axonal loss.

We do it with obvious wasted muscle patient, we want to:

  1. Confirm axonal loss affecting muscles bulk, thus confirming severity of CTS.
  2. Chronicity of the condition (Acute or chronic axonal injury)
43
Q

Conservative Treatment for CTS๐Ÿ”‘๐Ÿ”‘

A

Controlling Risk Factors

1- Exacerbating activities, such as repetitive or excessive wrist flexion and extension and gripping, should be avoided

2- Ergonomic changes

The wrist should be splinted in 0 to 5 degrees of extension. Wrist splints are widely available but frequently hold the wrist in greater than 30 degrees of extension. In this case the patient should be instructed in reducing the wrist extension angle of the metal plate along the dorsum of the wrist.

3- Treat underlying medical disorders

Physiotherapy

  • Physiotherapy: Passive Stretch & ROM Exercises

Orthosis

  • Orthotics: Hand splint neutral to 30-degree extension

Pharmacological

  • Nonsteroidal anti-inflammatory drugs (NSAIDs)
  • Diuretics
  • Vitamin B6.
  • Local corticosteroid injections

Cuccurollo 4th Edition Chapter 5 EDX pg395

44
Q

List 6 Poor Prognosis for CTS ๐Ÿ”‘

A

๐Ÿ’ก Old female patient, lost sensation and weak motor power, waster hand and easily provoked, EDX shows demyelination and axonal lesion.

History (Chronic Severe CTS)

  • Long duration >10 months in duration
  • Constant paresthesias not improved by hand shakes
  • Motor weakness

Examination

  • Atrophy of thenar muscles
  • Positive Phalenโ€™s test in <10 seconds

EDX

  • NCS: Prolonged latency
  • EMG: Abnormal spontaneous activity (FIBs, PSW, CRD)

Cuccurollo 4th Edition Chapter 5 EDX pg395

45
Q

Recovery time of CTS 2nd to pregnancy

A

It usually occurs at 6 months and resolves postpartum

46
Q

What are the causes of false-positive result in CTS? ๐Ÿ”‘

A
  1. Cold temperature
  2. Increased age
  3. Increased height
  4. Increased hand circumference

PMR Secrets 3rd Edition Chapter 18 Neuropathy pg155 Box 18-4

47
Q

List 3 EDX findings in Martin Gruber Anastomosis.๐Ÿ”‘๐Ÿ”‘

A

1- Falsely increased CV

2- Conduction block

Elbow median nerve CMAP > Wrist median nerve CMAP due to simultaneously stimulating the median and the ulnar nerve innervated muscles

3- Initial positive deflection of median nerve CMAP

Antecubital fossa stimulation resulting in volume conduction from ulnar nerve

Cuccurollo 4th edition Chapter 5 EDX pg395

48
Q

Pt. with carpel tunnel operated, after 1 week came with swelling, stiffness, pain & dislocation. What you should exclude? Management? ๐Ÿ”‘๐Ÿ”‘ EXAM

A

DDx

  1. Tendon rupture (iatrogenic)
  2. Infection in operation site
  3. Nerve damage
  4. Necrosis

Management

  1. Xray
  2. Wrist U/S
  3. MRI
49
Q

Ulnar Nerve Origin & Course ๐Ÿ”‘๐Ÿ”‘

Motor & sensory branches of ulnar nerve ๐Ÿ”‘๐Ÿ”‘

How can you differentiate sensory abnormalities in proximal vs distal ulnar nerve palsy? ๐Ÿ”‘๐Ÿ”‘

What branches before and after Guyon canal?

A

Origin

  • C8โ€“T1 Roots โ†’ lower trunk โ†’ medial cord โ†’ ulnar nerve.

Course

  • Medial surface of the medial head of the triceps runs in arcade of Struthers (AOS).
  • Retrocondylar groove between medial epicondyle and olecranon
  • Enters cubital tunnel โ€œthick fascia made from FCRโ€
  • Through Guyonโ€™s canal, it splits into three branches
    • Superficial sensory branch
    • Hypothenar branch
    • Deep motor branch

Ulnar n. at Forearm / Before Guyon Canal / After Cubital Canal

  1. Flexor carpi ulnaris (FCU)
  2. FDP (third and fourth)
  3. Palmar ulnar cutaneous nerve
  4. Dorsal ulnar cutaneous (DUC) nerve

Ulnar n. at Wrist / After Guyon Canal

  1. Superficial sensory branch (digital nerves)
  2. Hypothenar branch (digiti minimi)
  3. Deep motor branch
    • 2 Lumbricals
    • 4 Dorsal interossei (โ€œDABโ€: Abduction)
    • 3 Palmar interossei (โ€œPADโ€: Adduction)
    • Palmaris brevis
    • 1 Adductor pollicis
    • 1/2 Flexor pollicis brevis (deep head)

Sensation

  1. Palmar ulnar cutaneous nerve (Abnormal in proximal compressions)
  2. Dorsal ulnar cutaneous (DUC) nerve (Abnormal in proximal compressions)
  3. Dorsal digital nerves (Travels through Guyonโ€™s canal, abnormal in distal compression)

Cuccurollo 4th Edition Chapter 5 EDX pg396

50
Q

What is the 1-1/2 Nerve supply of ulnar n.

A

Cuccurollo 4th Edition Chapter 5 EDX pg397

51
Q

Mention the muscle and nerve supply of thumbs movements ๐Ÿ”‘๐Ÿ”‘

A
  1. Abduction โ†’ Abductor Pollicis Longus by PIN branch of Radial, Brevis by Median.
  2. Adduction โ†’ Adductor Pollicis by Ulnar (Froment Sign)
  3. Extenstion โ†’ Extensor Pollicis by PIN branch of Radial
  4. Flexion โ†’ Flexor Pollicis โ†’ Longus by Median, Brevis by Median & Ulnar
  5. Opposition โ†’ Opponens Pollicis by Median
52
Q

List 6 causes of paresthesia in the little and ring fingers ๐Ÿ”‘๐Ÿ”‘

List 4 DDx in unlar neuropathy

A
  1. Cervical myelopathy & Syrinx
  2. C8-T1 Root Impingement
  3. Lower Trunk Plexopathy: apical lung tumour
  4. Medial Cord: clavicular fracture/ TOS
  5. Humeral Fracture
  6. Ulnar Nerve Entrapment at elbow
  7. Ulnar Nerve Entrapment at wrist
  8. Tendinopathies โ†’ Tennis Elbow
53
Q

Give 2 neuro-musculoskeletal causes for claw hand

A

NMSK

  1. Median and ulnar n. palsy (Lower trunk, Klumpkeโ€™s Palsy)
  2. Thoracic Outlet Syndrome (Vascular)
  3. Charcot-Marie-Tooth Disease (Demyelination Polyneuropathy)

Ulner Claw

  1. Proximal ulnar neuropathy

Others

  1. Scarring dorsal hand burn
  2. Leprosy
54
Q

Compare ulnar compression at the elbow and the wrist with respect to motor and sensory findings. ๐Ÿ”‘๐Ÿ”‘

A

ELBOW - CUBITAL TUNNEL SYNDROME

Sensory

  • Abnormal dorsal ulnar cutaneous (DUC)
  • Abnormal palmar ulnar cutaneous branch (PUC)
  • Abnormal 4th-5th digital branches.
  • Numbness in medial hand and fingers

Motor

  • Weak grip & pinch
  • Numbness in medial hand and fingers
  • Abnormal flexor carpi ulnaris (FCU), flexor digitorum profundus (FDP) and all intrinsic muscles.

EDX

  • Amplitude drop or conduction block across the elbow.

WRIST - GUYONโ€™S CANAL SYNDROME

Sensory

  • Numbness in 4th and 5th finger tip only

Motor

  • Clawing of the ring and little finger
  • Abnormal intrinsic hand muscles
55
Q

Draw the ulnar nerve in the guyonโ€™s canal & structures passing ๐Ÿ”‘๐Ÿ”‘ EXAM 2018-2019

A

Guyon canal

  1. Ulnar nerve
  2. Ulnar artery

Contains no tendons, which possibly explains why injuries to it are more likely related to external compression than overuse, as is seen in CTS

SHEAโ€™S CLASSIFICATION SYSTEM

Type l: Involvement of the deep ulnar branch, hypothenar, and sensory

Type ll: Involvement of deep ulnar motor branches

Type lll: Involvement of the superficial ulnar sensory branch

Cuccurollo 4th Edition Chapter 5 EDX pg399

56
Q

30-Year-Old Male presented with pain, numbness and tingling sensation in the 4th, 5th digits of the left arm of 2 monthsโ€™ duration. How would you differentiate clinically if this is secondary to left C8-T1 Radiculopathy versus left ulnar entrapment neuropathy at the elbow or thoracic outlet impingement (TOS) (Neurogenic) ๐Ÿ”‘๐Ÿ”‘ MOCK

A

C8-T1 Radiculopathy (Radicular Pain)

  • Neck pain with dermatomal distribution at C8-T1

Ulnar entrapment neuropathy

  • Tenderness at left elbow, positive tinnelโ€™s sign

Neurogenic TOS

  • Left thumb abduction will be mainly affected
57
Q

Arcade of struthers Etiology, Presentation, 2 Signs & EDX Finding.

A

Arcade of Struthers

  • Fascial band in the medial arm that connects the brachialis to the triceps brachii
  • Ulnar nerve can be injured due to compression under the fascial band.

Clinical presentation

๐Ÿ’ก Like playing arcade

  1. Involvement of all motor branches of ulnar n. (Distal โ†’ Ulnar claw hand)
  2. Involvement of all sensory branches of ulnar n.
  3. Wrist flexion with a radial deviation (FCU weakness, unopposed action of FCR)
  4. Ulnar claw hand = Unopposed action of finger extensors affecting fingers pulley system leading to partial finger flexion of the fourth and fifth PIP and DIP and extension of MCP.

Examination

  1. Fromentโ€™s sign: Inability to adduct the thumb (adductor pollicis weakness) leading to relaying on median innervated FPL muscle causing thumb flexion.
  2. Wartenbergโ€™s sign: Inability to adduct the fifth digit (interossei weakness).

EDX

  1. Abnormal ulnar SNAP and CMAP
  2. Abnormal Dorsal ulnar cutaneous nerve SNAP (proximal injury)
  3. EMG: Abnormal activity in all the ulnar innervated muscles

Cuccurollo 4th Edition Chapter EDX pg397

58
Q

Tardy ulnar nerve palsy Etiology, PEx & EDX.

A

๐Ÿ’ก Ulnar neuropathy that can occur months to years after a distal humeral fracture.

  • Result from bone overgrowth or scar formation.
  • Involvement of all the ulnar nerve innervated muscles.
  • EDX findings: Abnormal ulnar SNAP and CMAP and abnormal EMG of all ulnar muscles

Cuccurollo 4th Ediiton Chapter 5 EDX pg398

59
Q

Cubital Tunnel: Presentation - PEx - EDX - Treatment

Borders of Cubital Tunnel. 3 marks ๐Ÿ”‘๐Ÿ”‘

A

Cubital Tunnel

  • Put your index between medial epicondyle and olecranon
    1. Medially: Medial epicondyle of the humerus
    2. Laterally: Olecranon process of the ulna
    3. Top is UCL and FCU tendon or aponeurosis.

Etiology

  • Compression beneath FCU aponeurosis or arcuate ligament.

Clinical presentation

๐Ÿ’ก Just like Pronator teres syndrome, sparing pronator muscles.

  • The FCU may or may not be involved.
  • All ulnar nerve innervated muscles
  • Numbness 1/2 fourth digit and fifth digit
  • Loss of dexterity and grip strength

PEx

๐Ÿ’ก FDP & FCU will be less affected since they branch in forearm

  • Atrophy of hand muscles, esp 1st Dorsal Interosseous & Abductor Digiti Minimi
  • โ€œclawingโ€ of the hand due to intrinsic muscle weakness
  • Positive Tinelโ€™s sign at the elbow

EDX

  • SNAP: Abnormal ulnar nerve and Dorsal ulnar cutaneous (DUC) findings
  • CMAP: Decrease in CV and conduction block
  • Abnormal activity in the ulnar nerve innervated (hand intrinsics > forearm) muscles

Treatment

  1. Patient education & lifestyle modification
  2. Avoid of strong, repetitive gripping โ†’ avoid finger flexion
  3. Avoid repetitive elbow flexion โ†’ limit nerve stretching
  4. Cushioning of the elbow to prevent compression โ†’ avoid compression

Cuccurollo 4th Edition Chapter 5 EDX pg398

60
Q

List 4 signs in Ulnar Neuropathy ๐Ÿ”‘๐Ÿ”‘

A
  1. Fromentโ€™s Sign
  2. Wartenbergโ€™s Sign (Weak interossie)
  3. Ulnar Claw Hand (Weak lumbricals +/- FDP)
  4. Static Benediction Sign
61
Q

When do you suspect C8-T1 Root pathology in ulnar n. palsy patient?

A

๐Ÿ’ก Go back to basics: Any root (radiculopathy) comes with neck pain and other involvement of the major trunk or cords.

  1. History of neck pain
  2. Weakness of thumb flexion and abduction (Median n.)
  3. Weakness of index finger extension (Radial n.)
  4. Sensory loss of medial forearm
  5. UMN Finding (Abnormal Reflexes)

Shapiro Chapter 22 Table 22.1

62
Q

List 6 Poor Prognosis for CTS ๐Ÿ”‘

A

History (Chronic Severe CTS)

  • Long duration >10 months in duration
  • Constant paresthesias not improved by hand shakes
  • Motor weakness

Examination

  • Atrophy of thenar muscles
  • Positive Phalenโ€™s test in <10 seconds

EDX

  • NCS: Prolonged latency
  • EMG: Abnormal spontaneous activity (FIBs, PSW, CRD)

Cuccurollo 4th Edition Chapter 5 EDX pg395

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