Download MBBS (Bachelor of Medicine, Bachelor of Surgery) Human Anatomy ppt lectures Topic 97 Median & Ulnar Notes. - anatomy ppt free download human anatomy ppt lectures, medicine notes ppt, anatomy handwritten notes pdf, mbbs 1st year anatomy notes pdf download, best anatomy notes pdf, human anatomy notes pdf, anatomy easy notes pdf, anatomy notes online, anatomy short notes, Anatomy ppt, Powerpoint Presentations and lecture notes.
Objectives
? Origin, course & relation of median & ulnar nerves.
? Motor & sensory distribution
? Carpal tunnel syndrome
? Claw hand
? Motor & sensory effects in cases of lesion of median
& ulnar nerves
? Clinical signs/tests
Median & Ulnar nerves
3
Ulnar & Median nerves - Brachial plexus
Median Nerve
Origin : (C5,6,7, & 8, T1)
? median nerve is formed
? by union of lateral and medial roots
? originating from lateral and medial
cords of brachial plexus.
? anterior to third part of axillary artery
Median Nerve
Origin : C5,C6,C7 & C8, T1
? median nerve is
formed anterior to
third part of axillary
artery by union of
lateral and medial
roots originating
from lateral and
medial cords of
brachial plexus.
Median Nerve in Arm
? At inferior margin of teres major muscle.
? Passes vertically down on medial side of arm in anterior
compartment and is related to brachial artery throughout
its course:
? proximal region lateral to brachial artery;
? distal region at mid point it crosses to medial side
of brachial artery and lies anterior to elbow joint.
Median nerve has NO major branches in arm, but a branch
to one of muscles of the forearm, pronator teres muscle,
may originate from it immediately proximal to elbow joint.
Median Nerve in Arm
Median nerve - C5,C6,C7 +
C8,T1
Origin: 2 roots - medial &
lateral cords of brachial plexus.
medial root crosses 3rd part of
axillary artery & join lateral
root , runs down on lateral
side of brachial artery.
Mid of arm, it crosses brachial
artery from lateral to medial
and continues down on its
medial side.
At elbow, it lies medial to
tendon of biceps & is crossed
by bicipital aponeurosis.
? no branches in arm.
9
Median Nerve in Forearm
? Median nerve passes
into forearm anterior to
elbow joint, where
branches innervate most
of muscles in anterior
compartment of forearm
(except for flexor carpi
ulnaris muscle and
medial half of flexor
digitorum profundus
innervated by ulnar
nerve).
Median nerve
In cubital fossa - lies deep to
bicipital aponeurosis.
Leaves cubital fossa & runs
b/w two heads of pronator
teres.
Descends b/w flexor
digitorum superficialis &
flexor digitorum profundus.
It reach palm deep to flexor
retinaculum or through
carpal tunnel deep to tendon
of palmaris longus & lateral
to tendon of flexor digitorum
superficialis.
11
Muscular: Pronator teres,
Median nerve in forearm Flexor carpi radialis , Palmaris
longus & Flexor digitorum
superficialis.
Palmar cutaneous branch: at
distal part of forearm &
superficial to flexor
retinaculum - skin of
lateral 2/3 of palm.
Articular: elbow joint.
Anterior interosseous nerve:
between FPL & FDP, anterior
to interosseous membrane.
It supplies : FPL+PQ+ lateral
half of FDP.
Articular branches: wrist &
distal radioulnar joint.
12
Median Nerve in Hand
? Median nerve continues into hand by
passing deep to flexor retinaculum.
? It innervates: Three thenar muscles of
thumb , Lateral 2 lumbrical muscles
associated with movement of index and
middle fingers;
? Skin over palmar surface of lateral three &
half digits and over lateral side of palm
and middle of wrist.
Median Nerve in Hand
? Enters palm through carpal
Median n in hand
tunnel, deep to flexor
retinaculum & divides
lateral & medial branches.
? Lies a fingerbreadth distal to
tubercle of scaphoid.
? Muscular: Thenar ? Muscles 5 .
? Abductor pollicis brevis.
? Flexor pollicis brevis. Thenar
? Opponens pollicis
Emi
nenec
e
Ms.
(deep to the above 2 ms.).
? Lateral 2 lumbricals (1st & 2nd ).
? Digital cutaneous branches : to
palmar aspect of lateral 3 ?
fingers
15
Median Nerve Lesion
? Injury of median nerve at different levels
cause different syndromes.
? In arm and forearm the median nerve is
usually not injured by trauma because of
its relatively deep position.
? Median nerve can be damaged:
Elbow region
At wrist above flexor retinaculum
In carpal tunnel
Median Nerve Lesion in Elbow Region
? Damaged in
supracondylar fracture
of humerus
? Muscles affected are:
? Pronator muscles of
the forearm
? All long flexors of
wrist and fingers
except FCU and
medial half of FDP
Median Nerve Lesion at Wrist
? Often injured by penetrating wounds (stab wounds or
broken glass) of the forearm.
? Motor:
? Thenar muscles are paralyzed and atrophy in time so thenar
eminence becomes flattened
? Opposition & abduction of thumb are lost, and thumb and
lateral two fingers are arrested in adduction & hyperextension
position .
? Apelike hand
? Sensory & trophic changes are same as in elbow
region injuries
Carpal Tunnel Syndrome
? The commonest neurological
problem associated with median
nerve is compression beneath
flexor retinaculum at wrist.
? Motor: Weak motor function of
thumb, index & middle finger
? Sensory: Burning pain or pi s
a d eedles along distribution
of median nerve to lateral 3?
fingers
No sensory changes over palm as palmer cutaneous branch
is given before median nerve enters carpal tunnel.
Lesion of median nerve - above elbow
? Weakness of flexion - wrist due
to paralysis of FCR & PL.
? Loss of pronation - paralysis of
pronator teres & quadratus.
? Loss of flexion of middle
phalanges of medial 4 fingers -
paralysis of FDS.
? Loss of flexion of terminal
phalanges of index & middle
fingers - paralysis of lateral ? of
? FDP.
? The most serious
disability of median
nerve injuries is:
? Loss of opposition
of the thumb. The
delicate pincer-like
action is not
possible
? Loss of sensation
from thumb and
lateral 3? fingers &
lateral of the pal
Median Nerve
? Origin: Medial and lateral cords
Motor
All muscles in anterior compartment of forearm
(except flexor carpi ulnaris and medial half of flexor
digitorum profundus), three thenar muscles of the
thumb and two lateral lumbrical muscles
Sensory
Skin over palmar surface of lateral three and one-half
digits and over lateral side of the palm and middle of
wrist
Motor Effects:
Wasting
of thenar
? Loss of pronation. Hand is kept in
eminence
supine position
? Wrist shows weak flexion, and
ulnar deviation
? Loss of flexion on interphalangeal
joints of the index and middle
fingers
? Weak flexion of ring and little
Ulnar deviation
finger
? Thumb is adducted and laterally
rotated, with loss of flexion of
terminal phalanx and loss of
opposition
? Wasting of thenar eminence
? Hand looks flattened and
apelike , and presents an inability
to flex three most radial digits
when asked to make a fist.
? Sensory Effects: Loss of
sensation from:
? The radial side of the palm
? Palmar aspect of the lateral
3? fingers
? Distal part of the dorsal
surface of the lateral 3?
fingers
? Trophic Changes:
? Dry and scaly skin
? Easily cracking nails
? Atrophy of the pulp of
fingers
Lesion of median nerve -above elbow
Loss of flexion of thumb - Flexor pollicis
longus & brevis
Loss of opposition of thumb - Opponens
pollicis.
Flatting/Wasting of Thenar eminence -
atrophy.
Ape ha d - Ape thumb deformity
Thenar eminence is flattened and thumb
is adducted & hyperextended.
Loss of cutaneous sensations - hollow of
palm + palmar surfaces of lateral 3 ?
fingers.
Lesion of median nerve -
above wrist
Loss of opposition of thumb
paralysis - opponens pollicis.
Flattening of thenar
eminence - atrophy of thenar
muscles.
Ape ha d or Ape thu b
Deformity.
Loss of cutaneous sensations
- palmar surfaces of the
lateral 3 ? fingers.
Carpal tunnel syndrome
? Compression of median nerve - carpal tunnel.
? Slight flattening of thenar eminence due to
wasting of thenar eminence muscles.
? Accompanied by bur i g pai or pi & eedles
with diminished cutaneous sensations on palmar
aspect of lateral 3 ? fingers.
? No paresthesia occurs over the thenar eminence
(because this area is supplied by palmar
cutaneous branch of median N) , arises in distal
part of forearm & descends superficial to flexor
retinaculum.
Carpal tunnel syndrome
Carpal tunnel syndrome
Ulnar nerve C8T1
Origin : medial cord of
brachial plexus , runs
medial to brachial artery -
middle of arm.
At coracobrachialis
insertion, - pierces medial
intermuscular septum, is
accompanied by superior
ulnar collateral artery ? and
enter posterior
compartment of arm.
At elbow - posterior to
medial epicondyle.
No branches in arm.
30
Ulnar nerve in forearm
? It continues downward
to enter in forearm
? b/w two heads of
flexor carpi ulnaris.
? It runs down forearm
between FCU and FDP.
? In lower half of forearm
it lies medial to ulnar
artery.
31
? Muscular: FCU & FDP
Ulnar nerve in Forearm
? Flexor carpi ulnaris.
? Medial ? of FDP
? Articular: elbow joint.
? Dorsal or posterior
cutaneous branch:
? Dorsal surface - medial
1/3rd of hand 1? fingers.
? Palmar cutaneous
branch : to supply skin of
palm of hand and medial
1? fingers.
? FDP ? lateral ? Median N
? Medial ? Ulnar N
32
Ulnar nerve in Hand
33
Ulnar nerve in Hand
? Enters the palm superficial to flexor
retinaculum,
? close to lateral border of pisiform bone.
? Then it divides into superficial & deep
branches.
? Superficial branch:
? It supplies palmaris brevis
? palmar aspect of medial 1? fingers.
34
Ulnar nerve in Hand
Deep branch:
? Runs b/w abductor digiti minimi & flexor digiti minimi.
? pierces opponens digiti minimi.
? Then passes laterally within concavity of deep palmar
arch.
? lies deep to flexor tendons.
? It supplies 14 muscles :
? Three hypothenar muscles.
? Adductor pollicis.
? All dorsal & palmar interossei.
? Medial 2 lumbricals.
35
Lesion of ulnar nerve above elbow - atrophy of
hypothenar muscles
Lesion of ulnar nerve above elbow
? Weakness of flexion at wrist paralysis of FCU
? Loss of flexion of terminal phalanges of ring & little
fingers paralysis of medial ? of FDP
? Paralysis of all interossei & medial 2 lumbricals (3rd &
4th).
? Characteristic deformity is - partial claw hand.
? Atrophy of hypothenar muscles.
? Fingers - hyperextended at metacarpophalangeal joints
& flexed at interphalangeal joints - ring & little finger.
? Loss of adduction of hand & thumb due to paralysis of
flexor carpi ulnaris & adductor pollicis.
Lesion of ulnar
nerve above
elbow - Loss of
cutaneous sensations
on front & dorsum of
medial 1/3 of hand +
medial 1 ? fingers.
? It leads to paralysis of
Lesion of ulnar
intrinsic muscles of hand as
nerve above
described above.
wrist
? deformity claw hand
? Loss of cutaneous sensations
of medial 1 ? fingers.
Test for Palmar interossei
Test for adductor &
for adduction of fingers.
opponens pollicis.
Test for Palmar interossei for
Test for adductor &
adduction of fingers.
opponens pollicis.
1. Which one of these nerves is concerning with the carpal tunnel
syndrome ?
a.ulnar nerve.
b.radial nerve.
c.median nerve.
d.axillary nerve.
2. Which muscle has double nerve supply ?
A Biceps.
B Extensor digitorum superficialis.
C flexor digitorum profundus.
D Triceps.
3. Ape hand is the characteristic deformity due to lesion of :
A Radial nerve.
B Ulnar nerve.
C Median nerve.
D Axillary nerve.
41
Pattern of injury
Pattern of root contribution to plexus:
Upper trunk lesion: Sensory loss in C5 & C6
Middle trunk lesion: Sensory loss in C7
Lower trunk lesion: Sensory loss in the combined C8
& T1 dermatomes
Principles of localization
Certain sites
Ulnar nerve & median nerve at elbow
Carpal tunnel ? median nerve
Single nerve - Elbow extension ~ Radial
Multiple nerves - Elbow flexion ~
Musculo cutaneous, Median
Complete claw
hand
Affection of:
1- Most of the small muscles of the hand (T1)
2- Ulnar flexors of the flexor compartment of forearm are partially
affected (C8)
WINGING OF
SCAPULA
Injury to axillary nerve
Anterior
Shoulder Dislocation
Dislocated Head
Normal Head
WRIST DROP
Median nerve injury at elbow
(hand of benediction)
Median nerve injury
A- Above Elbow:
B- Above Wrist:
1- Loss of pronation
1- No Loss of pronation
2- Week flexion
2- No Week flexion
3- Ulnar deviation
3- No Ulnar deviation
4- Inability to flex thumb
4- No Inability to flex thumb
5- Inability to oppose fingers
5- Inability to oppose fingers
6- Inability to flex middle digits
6- No Inability to flex middle digits
7- Inability to flex Index
7- No Inability to flex index and middle fingers
middle fingers
-Sensory loss
- Sensory loss
-Ape hand deformity
- Ape hand deformity
Adducted &
Extended
extended
index and
thumb
middle
Flat thenar
eminence
Flexed little and ring
CARPAL TUNNEL
SYNDROME
Ulnar nerve injury
A - Above Elbow:
1- Week flexion
2- Loss of adduction
3- Inability to adduct thumb
4- Inability to put hand in writing position
- Sensory loss
- Partial claw hand deformity
B - Above Wrist:
1- No Week flexion
2- No Loss of adduction
3- Inability to adduct thumb
4- Inability to put hand in writing position
- Sensory loss to fingers only
- Partial claw hand deformity is more
prominent (Ulnar paradox)
Ulnar canal syndrome/Guyon tunnel syndrome
Handlebar neuropathy
? Symptoms
? Tingling
? Numbness
? Pain on the outside or middle of the forearm; this
sensation of discomfort may run all the way to the
little finger.
? Treatment
? Anti-inflammatory medications
? Wrist splints
? Therapeutic exercises
An inability to oppose the thumb to the little
finger can result from damage to the
________ nerve.
a) Axillary
b) Musculocutaneous
c) Radial
d) Ulnar
e) Median
Hyperextension of the proximal phalanges of
the little and ring fingers can result from
damage to the ________ nerve.
a) Ulnar
b) Axillary
c) Radial
d) Median
e) Musculocutaneous
Wrist drop can result from damage to the
________ nerve.
a) Median
b) Ulnar
c) Radial
d) Anterior interosseous
e) Axillary
This post was last modified on 05 April 2022