Download Examination Of Nerves Of Upper Limb

Examination of Nerves Of Upper Limb
Learning Objectives
At the end of the lecture, the student should be able to:
 Know steps of neurological examination of the upper limbs.
 Define the terms Tone, Bulk & Power.
 What are deep tendon reflexes?
 Describe Light touch & Pin Prick, Vibration & Proprioception.
 Describe the Major Nerves of Upper Limb.
Examination of Nerves Of Upper Limb
Neurological Examination of Upper Limbs
Done in Four Steps:
•
•
•
•
Tone
Bulk
Power.
Sensations.
Tone
• Muscle tone is defined as the resistance to
passive stretching.
• Start at the shoulder, feeling how easy the
joint is to move passively. Then move down
to the elbow, wrist and hand joints again
assessing each limb’s tone in turn.
Bulk & Size
• Measure the circumference of the patient’s
forearm and arm, right and left, where the
circumference is greatest and record the
measurements.
• Look and feel the small muscles of the
patient’s hands when looking at the thenar
and hypothenar eminences. Always adduct
all fingers and the thumb.
• Look at the dorsum of the hand, noting the prominence of the
extensor tendons.
Muscle Power
• Assess the power of each of the muscle
groups.
Abduction of Arm (C5)
• Supraspinatus –Supraspinatus Nerve:
Stand behind the patient. He should let his
arms hang by his sides. Hold his elbow into
the side of his trunk while he attempts to
abduct the arm.
• Deltoid-Axillary Nerve: Resist abduction
after the arm has been abducted 45 degrees
and more away from the trunk.
Arm Adduction (C7)
• Pectoralis Major- Pectoral Nerves
• Latissimus Dorsi-Thoracodorsal Nerve
Have the patient flex at the elbow while the arm is
held out from the body at forty-five degrees. Then
provide resistance as they try to further adduct at
the shoulder. Test each shoulder separately.
Fixation of Scapula
• Trapezius Muscle-Spinal Accessory Nerve
Pulls scapula up and medial like in shoulder shrug.
• Rhomboids-Dorsal Scapular Nerve
Pull scapula upward and medially like in shruging the
shoulder.
• Serratus Anterior-Long Thoracic Nerve
Pulls scapula away from midline and forward.
Forearm Flexion (C5-6)
• Brachialis-Musculocutaneous
• Biceps Brachii-Musculocutaneous
Have the patient bend their elbow to ninety
degrees while keeping their palm directed
upwards. Then direct them to flex their forearm
while you provide resistance.
Forearm Extension (C7)
• Triceps Brachii-Radial nerve
Have the patient extend their elbow against
resistance while the arm is held out (abducted at
the shoulder) from the body at ninety degrees.
Wrist Flexion (C7,8 T1)
• Flexor Capii Radialis-Median Nerve
• Flexor Carpii Ulnaris-Ulnar Nerve
Let the patient flex his wrist against your resistance.
Wrist Extension (C7,8)
• Extensor Carpi Radialis (Longus and Brevis)Radial Nerve
• Extensor Carpi Ulnaris-Posterior Interosseous
Nerve
Let the patient to try to extend his wrist against
your resistance.
Finger Flexion (C7,8T1)
• Flexor Digitorum Superficialis-Median Nerve
• Flexor Digitorum Profudus-Ulnar & Anterior
Interosseous branch of Median.
Ask the patient to grip and squeeze your two fingers.
If the grip is normal, you will not be able to pull your
fingers out.
Finger Extension (C7)
• Extensor Digitorum-Posterior Interosseous
branch of Radial.
Ask the patient to keep his hand and wrist stiff
and prone. Use the edge of your left hand as a
fulcrum in the middle of the patient’s palm.
Attempt to flex the patient’s fingers with your
right hand.
Thumb Abduction (C7,8 T1)
• Abductor Pollicis Longus-Radial Nerve
• Abductor Pollicis Brevis-Median Nerve
Put the dorsum of the patient’s hand on a flat
surface. As him to raise the thumb vertically.
The surface of the pad of the thumb is at right
angles to the surface of the palm of the hand.
Apply resistance in opposite direction.
Thumb Opposition (T1)
• Opponens Pollicis: Median Nerve
Ask the patient to make pincer grip by pushing tips
of thumb and small finger. You have to pull open it
with force.
Finger Abduction (C8,T1)
• Dorsal Interossei & Abductor Digiti Minimi-Ulnar Nerve
Ask the patient to spread their fingers apart against
resistance.
Finger Adduction (C8,T1)
• Palmar interossei-Ulnar Nerve
To test for finger adduction, ask the patient to
extend his fingers and hold a piece of paper
between two of fingers. Then you pull it out.
Deep Tendon Reflexes
There are three reflexes in the upper limb • Biceps
• Triceps
• Supinator
It is vital to get your patient to relax as much as possible.
Biceps Jerk
• Support the patient's arm, with it flexed at roughly 60º,
placing your thumb over the biceps tendon and hitting
your thumb with the tendon hammer.
Triceps Jerk
• The triceps reflex is elicited by resting the patient's
arm across their chest and hitting the triceps tendon
just proximal to the elbow.
Supinator Jerk
• With the arm rested on abdomen, locate the
supinator tendon as it crosses the radius, place
three fingers on it and hit the fingers. This should give the supinator
reflex.
Sensations
Tested in different ways
•
•
•
•
Light touch
Pin prick
Vibration
Joint position or proprioception
Light touch & Pin Prick
• Lightly touch the patient's sternum with a
piece of cotton wool so that they know
how it feels.
• With eyes shut, lightly touch their arm
with the cotton wool.
• The places to touch them should test each
of the dermatomes - make sure you know
these!
• Tell the patient to say yes every time the
cotton wool is felt as it felt before.
• Repeat this using a light pin prick.
Vibration
• Use a sounding tuning fork (128 hz).
• Place the fork on the patient's sternum to show
them how it should feel.
• Then place it on the bony prominence at the base
of their thumb and ask if it feels the same.
• If it does, there is no need to check any higher.
• If it feels different move to the radial stylus and then to the
olecranon until it feels normal.
Proprioception
• Hold the distal phalanx of the thumb on either
side so that interphalangeal joint can be flexed.
• Show the patient that when you hold the joint
extended, that represents 'Up' whereas when you
hold it flexed that represents 'Down'.
• Ask the patient to close the eyes and, having moved the
joint a few times hold it in one position - up or down. Ask
which position the joint is in.
Dermatomes
Upper extremity dermatome innervation with the arm
supinated on an arm board
Upper extremity dermatome innervation with the arm
pronated on an arm board.
Sensory Nerves
Cutaneous nerve distribution of the upper limb
Major Nerves of Upper Limb
Major Nerves
Nerve
Sensory
Supply
Radial
Nerve
Back of thumb, Wrist extension C6, 7, 8
index, middle, and abduction
and 1/2 ring
of thumb in
finger;
palmer plane
back of forearm
Palmar and
Abduction of
C7, 8, T1
dorsal aspects fingers (intrinsic
of pinky and 1/2 muscles of
of ring finger
hand)
Palmar aspect of Abduction of
C8, T1
the thumb,
thumb
index, middle
perpendicular to
and 1/2 ring
palm (thenar
finger; palm
muscles).
below these
fingers.
Ulnar
Nerve
Median
Nerve
Motor Supply Root Value