Le Nerve Injuries

Question 1

What are the Lumbar dermatomes of the leg?

Answer 1

L1 - Uppermost leg at level of ASIS spiraling anterior and down to perineum (Actual perineum is S2/3)

L2 - Upper thigh from just below ASIS spiraling anterior Down to inner thigh below perineum

L3 - Upper middle Lateral thigh spiraling anterior Down to medial side from mid thigh to middle of the medial leg

L4 - Lower Lateral thigh spiraling anterior and down across skin above patella down anterior leg and around to medial side of lower leg, ankle, and foot

L5 - Lateral lowest part of thigh and skin Lateral to knee spiraling anterior and down to front of leg and middle foot

Question 2

What are the Sacral dermatomes?

Answer 2

S1 - Lateral aspect of the posterior thigh down to lateral foot

S2 - Medial aspect of posterior thigh down to medial bottom of foot; perineum

S3 - part of buttcheeck; Perineum

Question 3

Damage to which nerve presents as medial knee and leg pan?

Answer 3

Saphenous nerve

Question 4

Which nerve, when damaged, has a clinical presentation of sensory disturbance in lateral lower leg and foot with possible foot drop and pain at sire of compression?

Answer 4

Common peroneal

Question 5

Which nerve, when damaged, has a clinical presentation of shooting pain in the cutaneous distribution of the nerve?

Answer 5

Sural Nerve

Question 6

Which nerve, when damaged, has a clinical presentation of Numbness and/or pain in lateral Left; vague pain over Dorsal of foot; symptoms increase with cavity.?

Answer 6

Superficial peroneal nerve

Question 7

Trace the path of the Ilioinguinal nerve.

Answer 7

1. Pierces internal obliques 4cm medial to ASIS
2. Enters inguinal canal
3. Leaves through superficial ring
4. Supplies skin of medial thigh and adjoining scrotum/labia

Question 8

What are characteristics of inguinal entrapment?

Answer 8

Pain from:

• increased abdominal wall tension
• Hyperextension of hip
• Tenderness 4 cm media to ASIS

Question 9

Trace path of genitofemoral nerve.

Answer 9

From L1/2 follow2s anterior aspect of splash major and separates into genital and femoral branch

Genital: Enters inguinal ring ; union with ilioinguinal nerve on anterior aspect of spermatic cord; Suppliew Ventral aspect of scrotum and adductor region; cutaneous branches on dorsocaudal aspect

Femoral: Lies on lateral side of femoral artery; Pierces anterior wall of sweat and supplies skin below inguinal ligament;

Question 10

Describe the path of lateral cutaneous nerve

Answer 10

• Forms from lumbar plexus within Psoas Major
• Through lateral aspect of Psoas
• Pierces inguinal ligament
• lies in fibrous tunnel, divides into two and pierces deep fascia.

Question 11

What is characteristic of Lat cut nerve of thigh injury?

Answer 11

• entrapment in fasciae tunnel
• Assymetic bars in gymmnastics
• causes Meralgia paraesthetica
• also, damagecaused by post laparoscopic surgery

Question 12

What are the branches of the femoral nerve?

Answer 12

Muscular: Quads, sartorius, pectineus

Cutaneous: Medial cutaneous, intermediate cutaneous, saphenous

Articular: Hip and knee joint

Question 13

What is characteristic of femoral nerve damage?

Answer 13

• stretch by dancers via prolonged hyperextension of hip
• Compress under inguinal ligament
• Also compressed from hematoma following teat of iliacus

Question 14

Describe posterior Obturator entrapment

Answer 14

• Supplies adductor muscles above hiatus
• Spasms of adducator muscles
• May be entrapped as it leaves pelvis or btwn fasciae planes

Question 15

What is Howship Romberg sign?

Answer 15

• Pressure on obturator
nerve 
• Pain on inner aspect
of thigh relieved by
flexion of hip 
• Increased by
extension, adduction
and medial rotation

Question 16

Describe the path of the sciatic nerve.

Answer 16

• Is the largest nerve in diameter
in the body 
• It passes out of the pelvis
below piriformis and descends
between the greater trochanter
of the femur and the ischial
tuberosity 
• Passes deep to gluteus
maximus 
• More distally it lies on adductor
magnus
• Is crossed by the long head of
biceps femoris 
• Divides in middle of thigh
 • Tibial and common peroneal
nerves 
• Common peroneal may pierce
piriformis if divides in pelvis 
• Supplies hamstrings 
• Adductor magnus below
hiatus

Question 17

What is saphenous varix?

Answer 17

a localized
dilation of the terminal part of the
great saphenous vein causing
swelling in the femoral triangle just
inferior to the inguinal ligament

Question 18

Describe Tarsal

Tunnel syndrome.

Answer 18

• Tibial nerve compressed in tarsal tunnel
• distally, could be medial/lateral plantar nerves
• Caused by hyperdorsiflexion, External rotation, and aversion
• pain in pronation; pain in flexor Retinaculum; pain in either heel or sole of foot

Question 19

Describe Morton’s Metetarsalgia

Answer 19

• depressed transverse arch in runners and ballet dancers

- Neuroma on digital nerve to 2nd/3rd cleft.