L6: Pelvic Girdle & Pelvic Floor

Question 1

Examine the following skeletal components

Answer 1

The Coxal bone:
a) Ilium; b) ischium; c) pubis; d) iliac crest; e) ischial tuberosity; f) greater sciatic notch; g) lesser sciatic notch h) anterior superior iliac spine; i) anterior inferior iliac spine; j) posterior superior iliac spine; k) posterior inferior iliac spine; l) superior ramus of pubis; m) inferior ramus of pubis; n) pubic tubercle; o) obturator foramen; p) iliac fossa; q) iliac tuberosity; r) ischial spine; s) arcuate line; t) acetabulum; u) acetabular notch; v) inferior gluteal line; w) anterior gluteal line x) posterior gluteal line.

Question 2

Sacroilliac (Posterior, Anterior and Interosseous)
Sacrotuberous
Sacrospinous
Iliolumbar
Inguinal
Obturator membrane

Question 3

NOTE: the different foramen that are created by some of these ligaments (and what passes through these created foramen).

Answer 3

the greater and lesser sciatic foramen, is formed by the sacrospinous and sacrotuberous ligaments

nerves and tendons pass through

Question 4

Describe the structure of the pelvic girdle, and lists its functions.

Answer 4

The pelvic girdle is a bony structure that forms the base of the spine and supports the weight of the upper body. It consists of two hip bones, each composed of three fused bones: the ilium, ischium, and pubis. The hip bones articulate with the sacrum at the sacroiliac joints.

Functions of the Pelvic Girdle:

Support and Stability: The pelvic girdle supports the weight of the upper body and provides a stable foundation for the spine.
Attachment for Muscles: Muscles of the abdomen, back, and lower limbs attach to the pelvic girdle, allowing for movement and posture control.
Protection of Reproductive Organs: The pelvic cavity encloses and protects reproductive and urinary organs.

Question 5

What movements of the pelvis are important for walking? Why?

Question 6

What are the major differences between the male and female pelvis?

Answer 6

Pelvic Inlet Shape:
Male: Heart-shaped or oval.
Female: Round or oval, with a wider transverse diameter.

Pelvic Outlet:
Male: Narrower and deeper.
Female: Wider and shallower, facilitating childbirth.

Subpubic Angle:
Male: Acute (less than 90 degrees).
Female: Obtuse (greater than 90 degrees).

Pelvic Arch:
Male: More pronounced and narrower.
Female: Broader and more rounded.

Coccyx:
Male: Straighter and less movable.
Female: More curved and movable.

Question 7

Male vs. Female Pelvis Visual:

Answer 7

Question 8

Did you know?

Answer 8

The structure of the human pelvis, in its attachment to the vertebral column, permits an upright posture and locomotion on two legs (bipedal) rather than on four legs like other mammals (quadrupedal). Although these structures are well adapted for bipedal locomotion, an upright posture may cause problems. The sacroiliac joint may weaken with age, causing lower back pains. The weight of the viscera may weaken the walls of the lower abdominal area and cause hernias. Some of the problems of childbirth are related to the structure of the mother’s pelvis. The hip joint tends to deteriorate with age, and many older persons suffer from fractured hips.

Question 9

What are the MUSCLES OF PELVIC FLOOR AND WALLS?

Answer 9

Levator ani
Coccygeus (ischiococcygeus)
Obturator internus
Piriformis

dont need to know nerve supply

Question 10

Levator ani parts (3)

Answer 10

Puboprostaticus
Pubovaginalis
Pubococcygeus
liococcygeus
Puborectalis
Coccygeus

Question 11

Pubococcygeus

Answer 11

Origin: pubic symphysis

Insertion: the coccyx.

Function: support the pelvic organs, including the bladder and rectum,

Nerve Supply: dntk

Question 12

Iliococcygeus

Answer 12

Origin:
Arises from the arcus tendineus levator ani, which is a thick, fibrous structure in the pelvis.

Insertion:
Blends with the fibers of the pubococcygeus and coccygeus muscles and attaches to the coccyx.

Function:
It helps support pelvic organs such as the bladder and rectum

Question 13

Puborectalis

Answer 13

Origin: Arises from the pubic bone (specifically, the pubic crest and the pubic symphysis).

Insertion: Blends with the fibers of the external anal sphincter and the muscularis of the rectum.

Function: The puborectalis muscle is part of the levator ani muscle group and plays a crucial role in maintaining fecal continence by creating a loop or “sling” around the anorectal junction. It prevents involuntary passage of stool by maintaining a kink in the anorectal angle. When it relaxes, this kink straightens, allowing for defecation

Question 14

Coccygeus (ischiococcygeus)

Answer 14

O: Ischial spine
I: Inferior end of sacrum and coccyx
F: flexes coccyx, supports pelvic viscera
NS:?

Question 15

Obturator internus

Answer 15

O: Pelvic surface of ilium and ischium; obturator membrane
I: Greater trochanter of femur
F: Laterally rotates and abducts hip joint
NS:

Question 16

Piriformis

Answer 16

O: Lower sacral segments; superior greater sciatic notch and sacrotuberous ligament
I: greater trochanter
F: Laterally rotates hip joint; abducts hip joint;
NS: Anterior rami of S1 and S2