Atlas & Axis

Question 1

What are the abnormal signs in this radiograph?

Answer 1

1. Fracture line of the dens
2. Abnormal alignment (the distance between the dens and the lateral masses of c1 on both sides is not equal)
3. Prevertebral soft tissue swelling due to fracture edema

Question 2

What are the ligaments attached to the odontoid process?

Answer 2

• Transverse Atlantal ligament
• Apical odontoid ligament
• Alar ligament

Question 3

What is the type of joint is the atlantoaxial joint?

Answer 3

Synovial pivot

Question 4

What are the ligaments between C1 and C2?

Answer 4

• Ant. atlanto axial ligament
• Post. atlanto axial ligament
• Transverse ligament

Question 5

What is the first spinous process to be felt?

Answer 5

Spinous process of C7 (has a long spine = vertebra prominence)

Question 6

Why can we not feel the upper spinous processes (cervical vertebrae)?

Answer 6

1. Short
2. Bifid
3. Attached to the nuchal ligament

Question 7

What are the atypical features of C1, C2, C7?

Answer 7

• C1 (atlas): no body, no spine
• C2 (axis): body projects upwards to form the odontoid process, thick spine
• C7 (vertebra prominence): very long spine, smaller foramen transversum