Lumbar and Sacral plexus (460-466)

Question 1

Name some hinge joints in the lower limb;

Answer 1

Interplangeal joints of the toes. Knee joint (modified hinge as allows some rotation and side to side movement). Ankle joint (modified hinge)

Question 2

Name some gliding joints in the lower limb;

Answer 2

Patella and femur.Tarsal bones in foot.

Question 3

Name some ball and socket joints in the lower limb;

Answer 3

Hip (femur and acetabulum).

Question 4

Name the nerves that arise from the lumbar plexus;

Answer 4

Iliohypogastric (L1) [motor and sensory], Ilioinguinal (L1) [motor and sensory], Genitofemoral nerve (L1-L2) [motor and sensory], Lateral femoral cutaneous nerve (L2-L3) [sensory only], Obturator nerve (L2-L4) [motor and sensory], Femoral nerve (L2-L4) [motor and sensory]

Question 5

Name the nerves that arise from the sacral plexus;

Answer 5

5 major branches- Superior gluteal nerve (L4-5, S1), Inferior gluteal nerve (L5, S1-2), Sciatic nerve (L4-5, S1-3), Posterior femroal cutaneous (S1-3), Pudendal nerve (S2-4). Other small branches- nerve to piriformis, nerve to obturator internus, nerve to quadratus femoris.

Question 6

State the root values for the following nerves-
A) Femoral. B) Obturator.
C) Ilioinguinal. D) Genitofemoral.
E) Lateral femoral cutaneous nerve of the thigh. F) Sciatic.
G) Superior gluteal. H) Inferior gluteal.

Answer 6

A) L2-4. B) L2-4.
C) L1. D) L1-2.
E) L2-3. F) L4-S3.
G) L4-S1. H) L5-S2.

Question 7

State the nerve roots responsible for-
A) Knee extension. B) Knee flexion. C) Ankle dorsiflexion. D) Ankle plantar flexion

Answer 7

A) L3. B) S2. C) L4. D) S1.

(Hip flexion- L2. Hallux dorsiflexion- L5)

*Note myotomes overlap (e.g. femoral nerve which innervates quadriceps for knee extension is L2-4)