The Bony Pelvis

Question 1

Where are the pelvic inlet and outlet?

Answer 1

Question 2

What is the false pelvis?

Answer 2

The space between the pelvic inlet and the iliac crest, contains abdominal viscera

Question 3

What is the true pelvis?

Answer 3

The space between the pelvic inlet and outlet, where the pelvic viscera is located

Question 4

Forces that go through the hip joint can be […] x one’s body weight.

Answer 4

300

Question 5

What are some of the differences between men and women in the architecture of the pelvis?

Answer 5

Question 6

The pelvis is designed to disperse […]

Answer 6

Force

Question 7

What are the 3 main functions of the pelvis?

Answer 7

1) Site of muscle attachment
2) Distribution and transmission of forces
3) Support pelvic viscera

Question 8

With what does the pelvis articulate?

Answer 8

L5 and sacrum

Sacroiliac joint

Sacrococcygeal Joint

Pubic symphysis

Question 9

What is the true conjugate?

Answer 9

Line from sacral promentory to pelvic symphysis. Used as a measure to determine if vaginal delivery is an option for pregnant women (i.e. if the child will fit thorugh the birth canal of the mother).

Question 10

How is the pelvis oriented in a person?

Answer 10

Anteriorly rotated about 50 degrees. This is important because the weight of the organs and contents of the pelvic viscera does not lie on the muscles/fascia of the pelvic floor but instead on the bony support of the ischium and pubis bones. This anterior pelvic tilt also positions the sacrum to articulate with the lumbar spine so that the lumbar spine can maintain its lordotic curve.

Question 11

What is the type of joint between L5 and the sacrum? What ligament contributes significantly to the stabiity of this joint?

Answer 11

Symphysis joint

Anterior longitudinal ligament

Question 12

What type of joint is the sacroilliac joint?

Answer 12

Anterior = synovial plane joint between auricular surface of sarcum and ilium

Posterior = syndesmosis with interosseous ligament conneting sacral and ilial tuberosities

Question 13

What movements are possible at the SI joint?

Answer 13

Nutation - promontory of sacrum moves anteriorly, coccyx moves posteriorly

Counternutation - promontory of sacrum moves posteriorly, coccyx moves anteriorly

These movements occur most frequently with defecation and childbirth

Question 14

Why are there more ACL injuries in female athlete?

Answer 14

The acetabulum of females has more anteversion, which changes the orientation of the distal femur in the knee joint. Increased femoral anteversion leads to increased basal hip internal rotation and valgus knee alignment upon landing and is considered a risk factor for anterior cruciate ligament injury.

Question 15

What movement of the SI joint is occuring during walking?

Answer 15

Rotational nutation and counternutation

Question 16

Why is it important to know the movements at the SI joint?

Answer 16

Because the SI joint is often part of the differential diagnosis for lower back pain

Question 17

What are the 3 ligaments that provide static support to the SI joint?

Answer 17

Question 18

What type of joint is the pubic symphysis?

What movements are possible?

Answer 18

Secondary cartilaginous symphysis

Slight gliding

Question 19

The […] ligaments separates the greater and lesser sciatic foramens.

Answer 19

Sacrotuberous and sacrospinal

Question 20

What structures pass thorugh the greater sciatic foramen?

Answer 20

Piriformis

Superior gluteal nerve and artery

Inferior gluteal nerve and artery

Sciatic nerve

Posterior cutaneous nerve

Spinal nerve for quadratus femoris

Spinal nerve for obturator internus

Pudendal artery

Pudendal nerve

Question 21

The superior gluteal nerve and artery exit the greater sciatic foramen […] to the piriformis

Answer 21

Superior

Question 22

The inferior gluteal nerve and artery exit the greater sciatic foramen […] to the piriformis

Answer 22

Inferior

Question 23

Which 3 structures enter the posterior thigh via the greater sciatic foramen and then re-enter the pelvis via the lesser sciatic foramen?

Answer 23

Pudendal artery

Pudendal nerve

Spinal nerve for obturator internus

Question 24

What structures pass thorugh the lesser sciatic foramen?

Answer 24

Pudendal artery

Pudendal nerve

Spinal nerve for obturator internus

Tendon of obturator internus

Question 25

• What type of joint is the hip?
• What movements are allowed here?

Answer 25

• A synovial joint of the ball and socket type between the head of the femur and the acetabulum
• Flexion, extension, ABduction, ADduction, internal rotation, external rotation, circumduction

Question 26

What is the angle of inclination of the hip?

What is a normal range for this angle?

Answer 26

Angle between femoral neck and shaft in frontal plane

125 - 130 degrees

Question 27

What is coxa valgus?

Answer 27

Hip angle of inclincation is greater than 130 degrees. This leads to pushing out of the distal femur in the knee joint, so the knees are more lateral and are called bowed legs.

Question 28

What is coxa varus?

Answer 28

When the angle of inclination is less than 125 degrees. This would cause the distal condyles of the femur to be more medial than is normal, so the person will be knock kneed.

Question 29

What is femoral anteversion and retroversion?

What are the clinical consequences of this action?

Answer 29

Anteversion - the head of the femur is rotated more anteriorly, causing greater trochanter to be positioned more posteriorly. People compensate by “toeing in” (i.e. babies).

Retroversion - the opposite.