Joints Of Atlas And Axis: Atlanto-Occipital Joints

Question 1

Joints Of Atlas And Axis

Answer 1

1. Atlanto-occipital joints
2. Atlanto-axial joints

Question 2

Type

Answer 2

Synovial, ellipsoid variety

Question 3

Articular surface

Answer 3

1. Above: occipital condyles
2. Below: superior articular facets of atlas

Question 4

Capsule

Answer 4

Attached to articular surfaces margins

Question 5

Ligaments

Answer 5

No ligaments but anterior and posterior Atlanto-occipital membranes are attached to capsule and strengthen it

Question 6

Anterior atlanto-occipital membrane

Answer 6

Extends between foramen magnum anterior margin and atlas anterior arch

Question 7

Posterior atlanto-occipital membrane

Answer 7

Extends between foramen magnum posterior margin and atlas posterior arch

Question 8

Movements

Answer 8

1. Flexion and extension (nodding)
2. Slight lateral flexion

Question 9

Muscles producing flexion

Answer 9

1. Longus capitis
2. Rectus capitis anterior

Question 10

Muscles producing extension

Answer 10

1. Rectus capitis posterior major and minor
2. Splenius
3. Semispinalis capitis

Question 11

Ligaments and membranes attached to atlas

Answer 11

1. Transverse ligament
2. Cruciform ligament
3. Anterior atlanto-occipital membrane
4. Posterior atlanto-occipital membrane

Question 12

Transverse ligaments

Answer 12

Extends between tubercles on medial side of lateral mass atlas and lies behind dens

Question 13

Cruciform ligament

Answer 13

1. Transverse limb
2. Vertical limb

Question 14

Transverse limb

Answer 14

Transverse ligament of atlas

Question 15

Verticals limb

Answer 15

From middle of transverse ligament atlas and has:
1. Upper part (passes upwards to attach foramen magnum anterior edge)
2. Lower part (passes downwards to attach to back of axis body)