SACRAL PLEXUS REVIEW

Question 1

What is the SACRAL PLEXUS?

Answer 1

The ROOTS (VENTRAL RAMI) of SPINAL NERVES
L4-L5 and S1-S4 for the SACRAL PLEXUS; situated anterior to sacrum;
supplies BUTTOCKS, PERINEUM and LOWER LIMBS

Question 2

What muscles are supplied by FEMORAL NERVE?

MOTOR?

Answer 2

ILIACUS, SARTORIUS, RECTUS FEMORIS, VASTUS MEDIALIS/INTERMEDIUS/LATERALIS and
PECTINEUS (+obturator nerve).

Question 3

Mnemonic for all the BRANCHES of SACRAL PLEXUS

Answer 3

Some Irish People Came Traveling Quickly On Perfect Paper Planes Laughing Proudly!

-SUPERIOR GLUTEAL Nerve (L4,L5,S1)
-INFERIOR GLUTEAL Nerve (L5,S1,S2)
-nerve to PIRIFORMIS (S1,S2)
-COMMON FIBULAR division of Sciatic Nerve (L4-S3)
-TIBIAL division of Sciatic Nerve (L4-S3) & splits
-nerve to QUADRATUS FEMORIS and INFERIOR
GEMELLUS (L4,L5,S1)
-nerve to OBTURATOR INTERNUS and SUP.
GEMELLUS (L5,S1,S2)
-POSTERIOR CUTANEOUS (FEMORAL) nerve of thigh
(S1,S2,S3)
-PERFORATING CUTANEOUS nerve (S2,S3)
-PUDENDAL nerve (S2,S3,S4)
-nerve to LEVATOR ANI?
-PERINEAL BRANCH (S4)

Question 4

whats the distribution of SUPERIOR GLUTEAL NERVE?

ORIGIN?

Answer 4

Gluteus Medius, g. Minimus and Tensor Fasciae Latae

ORIGIN: L4,L5,S1

Question 5

whats the distribution of INFERIOR GLUTEAL NERVE?

ORIGIN?

Answer 5

Gluteus Maximus

ORIGIN: L5-S2

Question 6

whats the distribution of NERVE TO PIRIFORMIS?

ORIGIN?

Answer 6

PIRIFORMIS muscle

ORIGIN: S1,S2

Question 7

whats the distribution of NERVE TO QUADRATUS FEMORIS and INFERIOR GEMELLUS?
ORIGIN?

Answer 7

QUADRATUS FEMORIS and INFERIOR GEMELLUS

ORIGIN: L4,L5,S1

Question 8

Whats the distribution of NERVE TO OBTURATOR INTERNUS and SUPERIOR GEMELLUS?
ORIGIN?

Answer 8

OBTURATOR INTERNUS and SUPERIOR GEMELLUS muscles

ORIGIN: L5-S2

Question 9

Whats the distribution of PERFORATING CUTANEOUS?

ORIGIN?

Answer 9

SKIN of INFEROMEDIAL ASPECT of BUTTOCKS

ORIGIN: S2,S3

Question 10

whats the distribution of POST. CUTANEOUS FEMORAL nerve of thigh?
ORIGIN?

Answer 10

-Gives rise to INFERIOR CLUNEAL NERVES and
PERINEAL BRANCHES
ORIGIN: S1-S3
-skin of ANAL REGION, INFEROLATERAL aspect of BUTTOCK, SUPERIOR POSTERIOR aspect of THIGH, SUPERIOR CALF, SCROTUM (M), LABIA MAJORA (F)

Question 11

whats the distribution of PUDENDAL?

ORIGIN?

Answer 11

MUSCLES of the PELVIC FLOOR:
-Levator Ani, Superficial Transverse, Perineal,
Deep Transverse Perineal, Bulbospongiosus,
Ischiocavernosus, Sphincter Anus Externus, Urethral
Sphincter
musc of PERINEUM; SKIN OF PENIS and SCROTUM (M) and CLIT, LABIA MAJORA, MINORA, VAGINA (F)
ORIGIN: S2-S4

Question 12

what is the distribution of SCIATIC NERVE?

ORIGIN?

Answer 12

-ORIGIN L4-S3
-Splits into 2 divisions at the knee: TIBIAL N. and
COMMON FIBULAR N.

Question 13

what are the distributions of TIBIAL NERVE?

ORIGIN?

Answer 13

-POSTERIOR LEG MUSCLES: Gastrocmenius, plantaris,
Soleus, popliteus, tibialis posterior, flexor digitorum
longus and flexor hallucis longus muscles
ORIGIN: L4-S3

Question 14

WHAT ARE THE BRANCHES that come off of TIBIAL N.

and what is their distribution?

Answer 14

1) MEDIAL PLANTAR: ABDUCTOR HALLUCIS, FLEXOR
DIGITORUM BREVIS and FLEXOR HALLUCIS BREVIS
sensory-SKIN OVER MEDIAL 2/3 PLANTAR SURFACE
of FOOT

Question 15

WHAT ARE THE BRANCHES that come off of TIBIAL N.

and what is their distribution? #2

Answer 15

2) LATERAL PLANTAR: Remaining muscles of foot not
supplied by medial plantar nerve,
sensory- SKIN OVER LATERAL 1/3 PLANTAR SURFACE OF FOOT

Question 16

WHAT ARE THE BRANCHES THAT come off of

COMMON FIBULAR and their distributions?

Answer 16

SUPERFICIAL FIBULAR (LATERAL LEG MUSCLES)

DEEP FIBULAR (ANTERIOR LEG MUSCLES)