9/12 Gluteal Region

Question 1

gluteal region surface anatomy

• Located posterior to pelvis
• Superior & inferior boundaries:

– Iliac crest

– Gluteal sulcus : • Groove beneath gluteal fold

Answer 1

Question 2

ilium/ischium/pubis

Question 3

what are the three muscle attach lines on the ilium?

Answer 3

anterior and posterior gluteal line

inferior gluteal line

Question 4

which two areas on ilium are palpable?

Answer 4

iliac crest and posterior superior iliac spine

Question 5

medial aspect

Question 6

sacrum

Answer 6

Question 7

sacrum anterior aspect

Question 8

femur

Question 9

Two ligaments form two important foramina for the passage of structures into and out of the gluteal region

Answer 9

1. Greater sciatic foramen (all exit): • Gluteal neurovascular bundles

– Piriformis m. • Sciatic nerve • Posterior Femoral Cutaneous n. • pudendal n. and internal pudendal a. • Obturator internus/superior gemellus nerve

2. Lesser sciatic foramen:

• pudendal n. and internal pudendal artery (enter)
• Obturator internus/superior gemellus nerve (enter)
• Obturator internus (exit)

Question 10

which two ligaments form the greater and lesser sciatic foramen?

Answer 10

greater - sacrospinous ligament

lesser - sacrotuberous ligament

Question 11

Nerves of the Gluteal Region

• Cluneal (op. sp.Clunial) nerves: – Cutaneous
• Deep nerves: – Sacral plexus branches • Leave pelvis via _______

Answer 11

greater sciatic foramen

Question 12

Cluneal (Clunial) Nerves

(cutaneous nerves of gluteal region )

what are the three vertebral segments for superior middle and inferior cluneal N.?

Answer 12

Superior - L1-L3

middle - S1-S3

inferior - S1-S3

Question 13

deep gluteal region nerves

Question 14

deep gluteal region nerves

list the two nerves?

Answer 14

• Superior gluteal nerve: – Leaves pelvis superior to piriformis with superior gluteal artery – Runs between gluteus medius and gluteus minimus – Supplies gluteus medius, gluteus minimus, tensor fasciae latae
• Inferior gluteal nerve: – Leaves pelvis inferior to piriformis with inferior gluteal artery – Supplies gluteus maximus

Question 15

which is the largest nerve in the body?

Answer 15

sciatic nerve

Question 16

sciatic nerve divides into which two nerves?

Answer 16

• Leaves pelvis inferior to piriformis
• Runs inferiorly deep to gluteus maximus
• Usually divides about half way down thigh into tibial & common fibular nerves
• Does not supply any gluteal structures

Question 17

which cutaneous nerve innervates the largest body area?

Answer 17

Posterior Femoral Cutaneous Nerve

*Supplies more skin than any other cutaneous nerve

Question 18

Nerves of small lateral rotators

Quadratus Femoris/ Inferior Gemellus Nerve

Obturator Internus/ Superior Gemellus Nerve

Question 19

Obturator Internus/ Superior Gemellus Nerve

enters the pelvis region through? and exit?

Answer 19

• Leaves pelvis via greater sciatic foramen
• Reenters pelvis via lesser sciatic foramen

Question 20

Pudendal Nerve (Anterior divisions of S2-S4 ventral rami)

Answer 20

• Most medial structure exiting greater sciatic foramen
• Reenters pelvis via lesser sciatic foramen to supply perineal structures

Question 21

3 Branches arising from the internal illiac a.

• Superior gluteal art. • Inferior gluteal art. • Internal pudendal art.

Answer 21

Question 22

Superior Gluteal Artery

• Largest internal iliac artery branch
• Superficial branch: – _____M.
• Deep branch: – Gluteus medius, minimus, tensor fascia lata

Answer 22

Gluteus maximus

Question 23

Inferior Gluteal Artery

• Supplies to which three muscles?

It participates in which special blood supply in the thigh?

Answer 23

– Gluteus maximus

– Small lateral rotators

– Superior hamstrings

• Participates in cruciate anastomosis of thigh: – Transverse branch of the medial circumflex femoral artery – Terminal part of the transverse branch of the lateral circumflex femoral artery – First perforating artery – The inferior gluteal artery

*May provide blood to the leg if the femoral artery is occluded or severed

Question 24

Internal Pudendal Artery

• Reenters pelvis via _____with pudendal nerve
• Supplies _____ muscles & ext. genitalia
• Does not supply any gluteal structures

Answer 24

lesser sciatic foramen

perineal

Question 25

arteries of the gluteal region

Question 26

Intragluteal injections should be made in the supero-lateral part of gluteal region in order to avoid the _____ nerve and other gluteal nerves and vessels

Answer 26

sciatic

Question 27

Gluteal Musculature (Superficial)

Question 28

Gluteus Maximus * Largest gluteal muscle * Chief extensor of the thigh & lateral rotation * Slight extension of leg when working with tensor fascia lata * Innervated by which nerve?

Answer 28

Inferior gluteal nerve

Question 29

deep gluteal muscles after reflecting gluteal maximus M.

Answer 29

Question 30

Gluteus Medius and Minimus * Both partially covered by gluteus maximus * Gluteus medius over gluteus minimus * Thigh abduction & medial rotation (particularly gluteus minimus) * innervated by which nerve?

Answer 30

Superior gluteal nerve

Question 31

walking gait cycle

Answer 31

Question 32

Gluteus Medius and Minimus * Condition names: – **Gluteal gait** or **Duchenne’s Limp** – Positive Trendelenburg’s sign * Cause: – **Superior gluteal nerve injury** * Effect: – Patient loses steadying action of gluteus medius and minimus – Lean toward effected side during stance phase of gait

Question 33

Tensor Fascia Lata * Enclosed by \_\_\_\_\_ * Innervation: – \_\_\_\_\_\_ * Function: – Abducts, medially rotates, and flexes thigh – Slight extension of knee along with the gluteus maximus

Answer 33

fascia lata Superior gluteal nerve

Question 34

Distinct Feature of the Fascia Lata: iliotibial tract (“IT Band”) – Runs from iliac tubercle to a tubercle (Gerdy’s) on lateral tibial condyle – Reinforced by tendinous fibers from **tensor fasciae** **latae** and **gluteus maximus** – Function: • Assists in decelerating adduction of thigh • Laterally stabalizes knee • Extends leg, compensate for quadriceps paralysis via gluteus maximus flexion • Pulls patella laterally, antagonist of vastus medialis, and synergist with flexing vastus lateralis for this action • Stretch to treat chondromalacia patella

Answer 34

Question 35

Piriformis

Answer 35

* Lies deep to gluteus maximus * Medial to gluteus medius * Demarcates gluteal blood vessels and nerves…

Question 36

Question 37

Obturator Internus * L., Occlude or stop up * Leaves pelvis through lesser sciatic foramen

Question 38

Superior and Inferior Gemelli * L., Twins * “Extrapelvic parts of obturator internus” * With obturator internus form the “\_\_\_\_\_”

Answer 38

triceps coxae

Question 39

Question 40

Obturator Externus * Deep to pectineus * Attachments: – External margins of obturator foramen – Trochanteric fossa * Innervation: – Obturator nerve

Answer 40

Question 41

obturator muscles

Question 42

Quadratus Femoris

Question 43

schematic of gluteal muscles

Question 44

Answer 44

Ischial bursa Trochanteric bursa gluteofemoral bursa