Lumbar, Sacral and Coccygeal Plexuses

Question 0

Ilioinguinal and iliohypogastric nerves

Answer 0

Both arise from the anterior ramus of L1

Pierce transversus abdominis muscles near the anterior superior iliac spines and pass through the external and internal obliques to supply the abdominal muscles and skin of the pubic and inguinal regions

Question 1

Subcostal nerves

Answer 1

Anterior rami of T12

Pass through transversus abdominis and internal oblique to supply the external oblique and skin of anterolateral abdominal wall

Question 2

Lateral cutaneous nerve of thigh

Answer 2

Anterior rami of L2 and L3

Enters the thigh posterior to inguinal ligament just medial to anterior superior iliac spine and supplies the skin on the anterolateral surface of the thigh

Question 3

Femoral nerve

Answer 3

Anterior rami of L2-L4

Lateral border of psoas major and innervates iliacus before passing deep to inguinal ligament and going to anterior thigh.

Supplies flexors of hip and extensors of knee

Question 4

Genitofemoral nerve

Answer 4

Anterior rami of L1 and L2

Divides laterally to the common and external iliac arteries into femoral and genital branches

Question 5

Obturator nerve

Answer 5

Anterior rami of L2-L4

Medial border of psoas major through pelvis to medial thigh supplying the adductor muscles

Question 6

Lumbosacral trunk

Answer 6

Anterior rami of L4 and L5

Passes over ala of sacrum to join the anterior rami of S1-S4 nerves forming the sacral plexus

Question 7

Sciatic nerve

Answer 7

Anterior rami of L4, L5, S1-S3

Articular branches to hip joint, muscular branches to flexors of knee and all muscles in leg and foot

Question 8

Superior gluteal nerve

Answer 8

Anterior rami of L4, L5 and S1

Gluteus medius, gluteus minimus and tensor fascia latae muscles

Question 9

Inferior gluteal nerve

Answer 9

Anterior rami of L5, S1 and S2

Gluteus maximus

Question 10

Nerve to piriformis

Answer 10

Anterior rami of S1 and S2

Piriformis muscle

Question 11

Nerve to quadratus femoris and inferior gemellus

Answer 11

Anterior rami of L4, L5, and S1

Quadratus femoris and inferior gemellus muscles

Question 12

Nerve to obturator internus and superior gemellus

Answer 12

Anterior rami of L5, S1 and S2

Obturator internus and superior gemellus muscles

Question 13

Pudendal nerve

Answer 13

Anterior rami of S2-S4

Structures in perineum: sensory to genitalia, muscular branches to perineal muscles, sphincter urethrae and external anal sphincter

Question 14

Nerves to levator ani and coccygeus

Answer 14

Anterior rami of S3 and S4

Levator ani and coccygeus muscles

Question 15

Posterior femoral cutaneous nerve

Answer 15

Anterior rami of S2 and S3

Cutaneous branches to buttock and uppermost medial and posterior surfaces of thigh

Question 16

Perforating cutaneous

Answer 16

Anterior rami of S2 and S3

Cutaneous branch to medial part of buttock

Question 17

Pelvic splanchnic nerves

Answer 17

Anterior rami of S2-S4

Pelvic viscera via inferior hypogastric and pelvic plexus