Joints of the hip complex

Question 1

Is all of the acetabulum articular?

Answer 1

No

Lunate surface is weight bearing

Acetabular notch and fossa are non-articular

Question 2

Describe the shape of the epiphysis in the acetabulum until puberty?

Answer 2

Y shaped

Question 3

What crosses the actebular notch?

Answer 3

Ligament

Question 4

What fills in the space in the acetabulum?

Answer 4

Potential space filled with fat pad

Question 5

Describe the location of the fat pads within the hip joint?

Answer 5

Intra-articular

Extra-synovial

Question 6

What is the anatomical neck of the femur?

Answer 6

Line of growth plate

Question 7

Where is the fovea in the femur?

Answer 7

Head

Question 8

Where can traction epiphyses occur in the femur?

Answer 8

Greater and lesser trochanters

Question 9

Where is the intertrochanteric line/crest?

What is its significance?

Answer 9

Between greater and lesser trochanter

Line is anterior, crest is posterior

Ligament attaches here

Question 10

Where do blood vessels that supply the head of the femur enter the bone?

Answer 10

Enter growth plate just below anatomical neck

Question 11

What is the significance of pressure and traction epiphyses in the femur?

Answer 11

Pressure epiphyses are weight bearing

Traction epiphyses can form where ligaments or muscles attach

Question 12

Describe the orientation of the head of the femur?

What is the significance of this for the joint?

Answer 12

Directed upwards, medially and forwards

So, anterior part of head lies outside socket

Question 13

How is the anterior part of the head of femur that lies outside the acetabulum protected?

Answer 13

Psoas bursa

Question 14

What is the function of the psoas bursa?

Answer 14

Protects head of femur that lies outside acetabulum and tendon

Question 15

What in the acetabulum does the head of the femur articulate with?

Why?

Answer 15

Roof of acetabulum

Thickest cartilage here

Question 16

List the intra-articular structures in the hip joint?

Describe the function of each?

Answer 16

Labrum: deepens cup and increases SA

Ligament of head of femur: directs artery to femoral head

Question 17

Describe the bony architecture of the femur?

Answer 17

Two trabecular systems that intersect: superior (vertical and arcuate) and inferior (medial and lateral)

Question 18

Compare the functions of the vertical and arcuate bundles in the bony structure of the femur?

Answer 18

Arcuate bundle: resist bending forces on neck of femur

Vertical bundle: for weight bearing in stance

Question 19

Where is the site of weakness in the bony architecture of the femur?

Why?

Answer 19

Arcuate bundles

Degenerate with ageing

Question 20

Where does the line of gravity lie in relation to the hip joint?

Answer 20

Behind centre of joint

Question 21

Describe the position of greatest stability in the hip joint?

Why?

Answer 21

Extension

Abduction

Medial rotation

This is the close packed position where the ligaments are most taught

Question 22

Describe the ligamentous supports of the hip joint?

Answer 22

Iliofemoral ligament (strong, anterior)

Ischiofemoral ligament, Pubofemoral ligament (weaker, posterior)

Question 23

Describe the attachment of the ligaments of the hip joints?

Answer 23

Iliofemoral: ileum to femur (2 attachments)

Ischiofemoral: from ischeum, blends with capsule (no attachment to femur)

Pubofemoral: from pubis, blends with capsule (no attachment to femur)

Question 24

Describe the shape and function of the iliofemoral ligament?

Answer 24

Inverted V shape

Tighten and spiral medially when joint is in extension

Resist extension, prevent us from falling backwards

Question 25

What are the retinacular fibres in the hip joint? What is their function?

Answer 25

Reflections of fibrous tissue from capsule to femoral neck Contain vessels which supply head of femur

Question 26

Describe the movements that occur at the hip joint?

Answer 26

Flexion/extension Abduction/adduction Medial/lateral rotation

Question 27

Describe the rotation that occurs at the hip joint during locomotion?

Answer 27

Medial rotation in stance Lateral rotation in swing

Question 28

Which muscles stabilise the head of femur in the acetabulum?

Answer 28

Cuff of fixator muscles Dynamic support

Question 29

Describe the actions of gluteus medius and minimus?

Answer 29

Maintain position of pelvis in coronal plane (stop pelvis from falling to unsupported side) Abduct hip

Question 30

Describe the effect of injury to the gluteus medius and minimus?

Answer 30

Trendellenberg gait

Question 31

Which muscles are associated with the development of osteitis pubis?

Answer 31

Adductor muscles

Question 32

Describe the nerve supply to the hip joint?

Answer 32

Innervated by articular branches of femoral and obturator nerve Hilton's law: joint receives pain and proprioceptive fibres from branches to muscles that move the joint (also pass to overlying skin)

Question 33

Where does pain referred to the hip originate from?

Answer 33

Lumbar spine and SIJ

Question 34

Describe the blood supply to the hip joint?

Answer 34

Via anastamoses between branches of medial and lateral femoral circumflex arteries (normally from profunda femoris)

Question 35

Describe the structures that lie posterior to the hip joint that may be damaged in dislocation?

Answer 35

Sciatic nerve

Question 36

Describe traumatic dislocations of the hip joint?

Answer 36

Head of femur slips out back of joint Usually associated with fractured posterior lip of acetabulum

Question 37

Why is re-artculation important in traumatic dislocations of the hip joint?

Answer 37

To maintain blood supply Must be within 5-6 hours

Question 38

Describe the appearance of a leg with a fractured neck of femur? Why?

Answer 38

Muscle spasm causes external rotation and shortening of limb

Question 39

How can congenital dislocation of the hip joint be identified and treated?

Answer 39

Test in adduction Treat by putting hip into abducted posture \> adductor magnus pulls along line of femur and pulls head back into socket

Question 40

Which fracture leaves the hip joint particularly susceptible to disruption of blood supply?

Answer 40

Fractured neck of femur