Applied Anatomy of Gluteal Region and Bony Pelvis

Question 1

3 bones forming hip bone

Answer 1

• Ilium
• Ischium
• Pubis

Question 2

3 joints of pelvis

Answer 2

• Sacrococcygeal joint
• Pubic symphysis
• Sacroiliac joint

Question 3

Organs contained and protected by pelvis

Answer 3

• Distal ureters
• Bladder
• Rectum
• Prostate (M)
• Uterus (F)
• Ovaries (F)

Question 4

Key landmarks of pelvic region

Answer 4

• Pubic tubercle
• Pubic symphysis
• Ischial tuberosity
• Greater trochanter
• ASIS
• Iliac crest
• PSIS
• Natal cleft
• Gluteal fold
• Inguinal ligament
• Midpoint of inguinal ligament
• Midinguinal point
• Supracristal plane

Question 5

How many vertebrae form the sacrum?

Answer 5

5 (S1-5)

Question 6

What is the sacral promontory?

Answer 6

Vertebral body of S1 being very prominent anteriorly

Question 7

What are the ala of the sacrum?

Answer 7

Lateral expansions coming from S1

Question 8

What is the sacral canal?

Answer 8

Tube-shaped structure on posterior aspect of sacrum

Question 9

What passes through the sacral canal?

Answer 9

• Filum terminale
• Cauda equina

Question 10

How many vertebrae form the coccyx?

Answer 10

4

Question 11

What is sacralisation of L5?

Answer 11

• Where L5 fuses with the sacrum
• Means sacrum has 6 bones

Question 12

What is lumbarisation of S1?

Answer 12

• Where S1 doesn’t fuse in the sacrum
• Means sacrum has 4 bones

Question 13

Male vs female pelvic inlets

Answer 13

• M = more heart-shaped, narrower
• F = more circular, wider

Question 14

Male vs female pubis

Answer 14

• M = narrower - narrower subpubic angle
• F = wider - wider subpubic angle

Question 15

Boundaries of pelvic inlet (posterior to anterior)

Answer 15

• Promontory
• Margin of ala
• Arcuate line
• Pecten pubis
• Pubic crest

Question 16

What is the linea terminalis?

Answer 16

Pubic crest, pecten pubis and arcuate line collectively

Question 17

Ligaments of the pelvis

Answer 17

• Sacroiliac ligaments
  > Anterior
  > Posterior
  > Interosseus
• Sacrospinous ligament
• Sacrotuberous ligament
• Sacrococcygeal ligament
• Pubic ligaments
  > Superior
  > Inferior

Question 18

Boundaries of pelvic outlet (anterior to posterior)

Answer 18

• Pubic symphysis
• Ischiopubic rami
• Ischial tuberosity
• Sacrotuberous ligament
• Coccyx

Question 19

Components of the pelvic diaphragm

Answer 19

• Levator ani
• Ischiococcygeus

Question 20

What is levator ani made of?

Answer 20

• Pubovaginalis
• Pubococcygeus
• Puborectalis
• Iliococcygeus

Question 21

Structures that pass through pelvic diaphragm

Answer 21

• Ureter
• Cervix
• Anal canal

Question 22

What is the iliotibial tract and where does it run from and to?

Answer 22

• Thick band of fascia lata
• From iliac crest to lateral condyle of tibia

Question 23

Which muscles insert into the iliotibial tract?

Answer 23

• Tensor fascia lata
• Gluteus maximus

Question 24

Functions of iliotibial tract

Answer 24

• Help steady pelvis on thigh
• Keep knee extended in erect position

Question 25

Origin, insertion, action and innervation of gluteus maximus

Answer 25

- O = external surface of ilium behind posterior gluteal line, back of sacrum + coccyx, sacrotuberous ligament - Ins = gluteal tuberosity of femur (deeper 1/4), iliotibial tract (rest) - A = hip extensor, knee extensor - Inn = inferior gluteal nerve (L5-S2)

Question 26

Origin, insertion, action and innervation of gluteus medius and minimus

Answer 26

- O = gluteal surface of ilium - Ins = greater trochanter - A = hip abduction, stabilising + maintaining balance of pelvis during walking - Inn = superior gluteal nerve (L4-S1)

Question 27

What is Trendelenburg sign?

Answer 27

Patient is unable to stabilise hip when standing on one leg

Question 28

What causes Trendelenburg sign?

Answer 28

- Weak or paralysed hip abductors - Affected side cannot stabilise pelvis when standing on affected side's leg - Unaffected side of pelvis drops

Question 29

What is Trendelenburg's gait?

Answer 29

- Person is seen lurching toward weakened side when normal sided foot is raised - When normal foot sided foot is raised, there is a tilt towards unsupported side, so person leans towards weakened side to compensate

Question 30

6 lateral rotators of the hip

Answer 30

- Piriformis - Obturator internus - Obturator externus - Quadratus femoris - Superior gemellus - Inferior gemellus

Question 31

What passes through the greater sciatic foramen above piriformis?

Answer 31

- Superior gluteal vessels - Superior gluteal nerve

Question 32

What passes through the greater sciatic foramen below piriformis?

Answer 32

- PIN PINS: > Pudendal nerve > Internal pudendal vessels > Nerve to obturator internus > Posterior cutaneous nerve of thigh > Inferior gluteal vessels + nerve > Nerve to quadratus femoris > Sciatic nerve

Question 33

What passes through the lesser sciatic foramen?

Answer 33

- PINT: > Pudendal nerve > Internal pudendal vessels > Nerve to obturator internus > Tendon of obturator internus