peripheral nerve lesions

PERIPHERAL NERVE INJURIESDr. Mansoor Khan, MBBS, FCPS I, Resident Surgery, KTH,

Peshawar

A N A T O M YConnective tissue

(epineurium, perineurium, endoneurium)

Nerve tissue(axon, schwann cell)

A

N

A

T

O

M

Y

EPINEURIUM

PERINEURIUM

ENDONEURIUM

VESSELS

NERVE INJURIES

Acute injury Chronic injury

PERRIPHERAL NERVE INJUIES

N e u r o p r a x i a

Mildest form, reversible conduction block(function loss), for hours or days due to direct mechanical

compression, ischemia, mild burn trauma or stretch

A x o n t m e s i sAxonal and myelin sheath disruption while

fascicular integrity is maintained--Wallerian degeneration occurs (prognosis is good—days,

weeks)

N e u r o t m e s i sLaceration from sharp or blunt forces causing complete

disruption of the axon and supporting connective tissue---very poor prognosis without surgical repair

C l i n i c a l S i g n s Motor function, Tinel’s sign (positive-sensory function

negative (after 4-6weeks)-total interruption, Sweating-

sympathetic fiber, Sensory function

Muscle atrophy start : post-injury 1 month

peak : 3rd - 4th month

C h r o n i c N e r v e E n t r a p m e n t

Paresthesia

Loss of function

Pain

P a t h o p h y s i o l o g yDirect compression

Segmental demyelination Wallerian degeneration(distal)

Ischemia Swelling of nerve

Microcompartment SD

C a r p a l T u n n e l S y n d r o m e

PREGNANCY

TYPE WRITING

PAIN & PARASTHESIA DISTRIBUSION

RELEASE SURGERY

SUPRA-CONDYLAR FRACTURE anterior displacement

M

E

D

I

A

N

N

E

R

V

E

Radial Nerve Entrapment Posterior Interosseous Nerve Syndrome

Radial Nerve Entrapment Posterior Interosseous Nerve Syndrome

RADIAL NERVE INJURYFracture of shaft of humrus

RADIAL NERVE INJURY

WRIST DROP

GUYON’S CANNAL SYNDROME

U

L

N

A

R

N

E

R

V

E

CUBITAL TUNNEL SYNDROME

U

L

N

A

R

N

E

R

V

E

CUBITAL TUNNEL SYNDROME

U

L

N

A

R

N

E

R

V

E

Benediction postureCLAWING OF RING & LITTLE FINGER

U

L

N

A

R

N

E

R

V

E

FROMENT’S SIGN Flexior pollicus longus (median nerve) compensates for a weak adductor pollicis (ulnar nerve)

U

L

N

A

R

N

E

R

V

E

CUBITAL TUNNEL SYNDROME Ulnar nerve Release surgery

U

L

N

A

R

N

E

R

V

E

COMMON PERONEALFracture of the head of fibula

PERONEAL NERVE INJURY SYMPTOMSDecreased sensation, Slapping gait, foot drop, toes drag

FACIAL NERVE Anatomy

FACIAL NERVE Anatomy

FACIAL NERVE PALSY LOSS OF FRONING, DROOPING, EYEBROW DROP

C o n s e r v a t i v e t r e a t m e n t

IndicationsShort history, mild-moderate, intermittent,

reversible cause (pregnancy, oral contraceptive,endocrine abnormalities, type writer)

MethodNon-steroidal anti-inflammatory drugs, splint

T r e a t m e n t

Time of operation

Open injury Closed injury

Early intervention Delayed intervention Delayed intervention

S u r g i c a l I n d i c a t i o n s

Failed conservative treatment

Severe injury (sensory loss, muscle atrophy, motor weakness)

E p i n e u r a l R e p a i r

F a s c i c u l a r R e p a i r

N e r v e G r a f t