Spinal Nerves

Question 1

Paralysis of serratus anterior:
* What nerve is damaged?
* What does it cause?
* What is the appearance?
* What cannot be done?

Answer 1

• Injury to the long thoracic nerve
• The medial border of the scapula moves laterally and posteriorly away from the thoracic wall
• This gives the scapula the appearance of a wing. When the arm is raised, the medial border and inferior angle of the scapula pull markedly away from the posterior thoracic wall, a deformation known as a winged scapula
• The arm cannot be abducted above the horizontal position because the serratus anterior is unable to rotate the glenoid cavity superiorly to allow complete abduction of the limb.

Question 2

For lateral winging what is injuried?

Answer 2

Probelm with/injury to spinal accessory nerve to trapezius or dorsal scapular nerve to rhomboids

Question 3

Answer 3

Question 4

What are the boundaries of the axilla?

Answer 4

• Anterior: pectoralis major and minor
• Medial: serratus anterior or ribs
• Lateral: proximal shaft of humerus
• Posterior: Subscapularis+teres major+lat dorsi
• Base: skin or axilla (arm pit) or 5th rib

Question 5

Where is the thoraic outlet?

Answer 5

Btw first rib and clavical

Question 6

What is a type of thoracic outlet syndromes? What is the cause and what are the symptoms?

Answer 6

Costoclavicular syndrome— pallor and coldness of the skin of the upper limb and diminished radial pulse resulting from compression of the subclavian artery between the clavicle and the 1st rib, particularly when the angle between the neck and the shoulder is increased.

Question 7

Answer 7

Question 8

Answer 8

Question 9

Answer 9

Question 10

What does the musculocutaneous nerve inn motor and cutaneous?

Answer 10

Motor:
- Coracobrachialis
- Biceps brachii
- Brachialis

Cutaneous:
- Lateral forearm

Question 11

What is the motor and cutanous inn of the median nerve?

Answer 11

Motor:
- Most anterior forearm compartment muscles expect FCU and FDP

Cutaneous:
* Lateral palm and fingers 1-3

Question 12

What is the motor and cutaneous inn of the axillary nerve?

Answer 12

Motor:
- Teres minor
- Deltoid

Cutaneous:
- Inferior deltoid

Question 13

What is the motor and cutaneous inn of ulnar nerve?

Answer 13

Motor:
- FCU
- Intrinsic hand muscles (form a fist)

Cutaneous:
- 4th & 5th finger, palmar and dorsal hand.

Question 14

What is the motor and cutaneous inn of the radial nerve?

Answer 14

Motor:
- All posterior arm and forearm muscles

Cutaneous:
- Posterior arm, forearm, most of lateral dorsal hand

Question 15

What runs in the medial aspect of the bicep

Answer 15

Ulnar nerve, brachial artery ad median nerve

Question 16

What can be injuried in a fractured humerus?

Answer 16

• Radial nerve because it runs posterior to the humerus
• BUT: Near the head of the humerus is the axillary nerve!

Question 17

What runs close to the median nerve?

Answer 17

Brachial artery and vein

Question 18

What is the roof of the carpal tunnel?

Answer 18

Flexor retinaculum

Question 19

• When does atrophy of the deltoid occur?
• What does it look like?

Answer 19

• Atrophy of the deltoid occurs when the axillary nerve (C5 and C6) is severely damaged (e.g., as might occur when the surgical neck of the humerus is fractured).
• As the deltoid atrophies unilaterally, the rounded contour of the shoulder disappears, resulting in visible asymmetry of the shoulder outlines. This gives the shoulder a flattened appearance and produces a slight hollow inferior to the acromion.

Question 20

Musculocutaneus nerve injury:
* Inflicted by what?
* What does it result in?
* Loss of what?

Answer 20

• Injury to the musculocutaneous nerve in the axilla is usually inflicted by a weapon such as a knife.
• A musculocutaneous nerve injury results in paralysis of the coracobrachialis, biceps, and brachialis; consequently, flexion of the elbow and supination of the forearm are greatly weakened.
• Loss of sensation may occur on the lateral surface of the forearm supplied by the lateral cutaneous nerve of the forearm.

Question 21

• What is the carpal tunnel syndrome from?
• What is the most sensitive structure in the carpal tunel?

Answer 21

• Results from any lesion that significantly reduces the size of the carpal tunnel or, more commonly, increases the size of some of the structures (or their coverings) that pass through it (e.g., inflammation of the synovial sheaths).
• The median nerve is the most sensitive structure in the carpal tunnel and, therefore, it is the most affected

Question 22

Lesions of the median nerve usually occur in two places: Explain the difference and what happens in each

Answer 22

Wrist
- Most common site is where nerve passes through the carpal tunnel.
- Laceration of wrist often causes median nerve injury because nerve relatively close to surface.
- Paralysis and wasting of the thenar muscles and the first two lumbrical muscles.
- Opposition of the thumb is not possible, and fine movements of the 2nd and 3rd digits are impaired.
- Sensation lost over the thumb and adjacent two and a half digits.

Forearm
- Perforating wound in elbow region results in loss of flexion of the proximal and distal interphalangeal joints of the 2nd and 3rd digits.
- This condition is caused by the inability to oppose and by limited abduction of the thumb (Fig. B3.16).

Question 23

Ulnar nerve injury:
* Where is injury?
* What happens when there is an injury at the elbow, wrist or hand?
* What happens when their is compression of the ulnar nerve?

Answer 23

Injury posterior to the medial epicondyle of the humerus most common.

Ulnar nerve injury occurring at the elbow, wrist, or hand
- extensive motor and sensory loss to the hand.
- denervates most intrinsic hand muscles - difficulty making a fist
- cannot extend the interphalangeal joints when trying to straighten the fingers. characteristic appearance of claw hand

Compression of the ulnar nerve through the ulnar tunnel (Guyon tunnel).
- Ulnar canal syndrome is manifest by hypoesthesia in the medial one and one half fingers and weakness of the intrinsic hand muscles.
- Clawing of the 4th and 5th fingers may occur

Question 24

What is handlebar neuropathy?

Answer 24

a neuropathy caused by extrinsic repetitive compression of ulnar nerve at wrist.

Question 25

Radial nerve injury: * What is the clinical manifestation? * What is not loss?

Answer 25

* Injury is proximal to the branches to the extensors of the wrist, so wrist-drop is the primary clinical manifestation. * Loss of sensation does not occur because the deep branch is entirely muscular and articular in distribution.

Question 26

* What is the bicipital myotatic reflex? * What is a normal or positive response? * What does it confirm? * What if something is wrong?

Answer 26

* The biceps reflex is one of several deep tendon reflexes that are routinely tested during physical examination. * A normal (positive) response is an * involuntary contraction of the biceps, felt as a momentarily tensed tendon, usually with a brief jerk-like flexion of the elbow. * A positive response confirms the integrity of the musculocutaneous nerve and the C5 and C6 spinal cord segments. * Excessive, diminished, or prolonged (hung) responses may indicate central or peripheral nervous system disease.

Question 27

What are the lumbar plexus nerves and sacral plexus nerves?

Answer 27

Question 28

Answer 28

Question 29

What is contained in the femoral triangle?

Answer 29

N = femoral nerve. A = femoral artery. V = femoral vein. EL = empty space (femoral canal) and lymphatics. | Lat to med

Question 30

Where does the sciatic run?

Answer 30

Deep to piriformis then btw retus and semitend

Question 31

What happens when you injury your superior gluteal nerve?

Answer 31

* When a person is asked to stand on one leg, the gluteus medius and minimus normally contract as soon as the contralateral foot leaves the floor, preventing tipping of the pelvis to the unsupported side * When a person with a lesion of the superior gluteal nerve is asked to stand on one leg, the pelvis descends on the unsupported side (Fig. B7.10B), indicating that the gluteus medius on the contralateral side is weak or nonfunctional. * This is referred to clinically as a positive Trendelenburg test.

Question 32

Incomplete section of the sciatic nerve (e.g., from a stab wound) may involve what?

Answer 32

the inferior gluteal and/or the posterior femoral cutaneous nerves

Question 33

Recovery from a sciatic lesion is slow and usually incomplete. * With respect to the sciatic nerve, the buttocks have a side of safety which is what? Danger side?

Answer 33

* side of safety (its lateral side) and a side of danger (its medial side) * Wounds or surgery on the medial side may injure the sciatic nerve and its branches to the hamstrings.

Question 34

What happens when you have an injury to the medial side of the sciatic nerve?

Answer 34

Paralysis of these muscles results in impairment of thigh extension and leg flexion.

Question 35

A pain in the buttocks may possibly result from what?

Answer 35

from compression of the sciatic nerve by the piriformis muscle (piriformis syndrome).

Question 36

Posterolateral herniation is most common in the lumbar region; approximately 95% of protrusions occur where?

Answer 36

at the L4–L5 or L5–S1 levels.

Question 37

What is sciatica? What is it often caused by?

Answer 37

Sciatica, pain in the lower back and hip and radiating down the back of the thigh into the leg, is often caused by a herniated lumbar IV disc or osteophytes that compress the L5 or S1 component of the sciatic nerve.

Question 38

Answer 38

Question 39

Injury to tibial nerve: * Why it is uncommon? * What can damage the nerve? * What does it cause?

Answer 39

* Injury to the tibial nerve is uncommon because of its protected position in the popliteal fossa; however, the nerve may be injured by deep lacerations in the fossa. * Posterior dislocation of the knee joint may also damage the tibial nerve. * Severance of the tibial nerve produces paralysis of the flexor muscles in the leg and the intrinsic muscles in the sole of the foot. * People with a tibial nerve injury are unable to plantarflex their ankle or flex their toes. * Loss of sensation also occurs on the sole of the foot.

Question 40

Answer 40

Question 41

TDAVNH?

Answer 41

T: tibialis posterior m D: flexor digitorum longus m A: artery (posterior tibial) V: vein (posterior tibial) N: nerve (tibial) H: flexor hallucis longus m

Question 42

Answer 42

Question 43

What is in the anterior, lateral and posterior compartment of the leg?

Answer 43

Question 44

Answer 44

Question 45

What is the cutaneous inn from obturator and femoral nerve?

Answer 45

Question 46

* What is an injury to the common fibular nerve? * What does it cause?

Answer 46

* Footdrop and compensating gait patterns. * Because of its **superficial and lateral position**, the common fibular nerve is the nerve most often injured in the lower limb. * It winds subcutaneously around the **fibular neck**, leaving it vulnerable to direct trauma. This nerve may also be severed during fracture of the fibular neck or severely stretched when the knee joint is injured or dislocated. * Severance of the common fibular nerve results in **flaccid paralysis of all muscles in the anterior and lateral compartments of the leg (dorsiflexors of ankle and evertors of foot).** * **The loss of dorsiflexion of the ankle causes footdrop, which is exacerbated by unopposed inversion of the foot**. This has the effect of making the limb “too long”: The toes do not clear the ground during the swing phase of walking

Question 47

Deep Fibular Nerve Entrapment: * What is it caused by? * What many it cause? * Pain occurs where?

Answer 47

Question 48

Medial Plantar Nerve Entrapment: * Caused by what? * Why does it occur? * What can it be called?

Answer 48

Question 49

What does the patellar tendon and calcaneal tendon reflex test?

Answer 49

Question 50

Plantar reflex: * What is a normal response? * What is an abnormal response? * What population is different and why?

Answer 50