The document discusses the atlanto-occipital and atlanto-axial joints, including their anatomical characteristics, movements, and clinical implications. It covers the cervical vertebrae's features, the structure and function of the atlas and axis, and the types of movements possible at these joints. Additionally, it addresses conditions such as occipitalization of the atlas and various fractures associated with the atlanto-axial joint.

1. ATLANTO-OCCIPITAL JOINT
&
ATLANTO-AXIAL JOINT
SHUBHAM SINGH

2. TOPIC TO BE PRESENTED
 Introduction to cervical vertebrae.
 Characteristic of cervical vertebrae.
 Atlanto-occipital joint.
 Introduction to atlas and occipit.
 Introduction to axis
 Atlanto-axial joint.
Clinical anatomy

3. A. Introduction to cervical vertebrae
Identifying feature:
The cervical vertebrae are identified by the presence of
foramania transversaria in transverse process.
Fig: a typical cervical vertebrae
Foramania
transversia

4. Characteristic
 These are 7 in no. of which 3rd to 6th are typical
while1st, 2nd and 7th are atypical.
 Small body.
 Transverse process is relatively short.
 Pedicles are long and directed backward and laterally.
 Lamina is long and narrow.
 Short spinous process.
 Vertebral foramen is larger than the body and
triangular in shape.
 Flat articular facets.

5. Fig: a typical cervical vertebrae

6. THE JOINT
A. Atlanto - Occipital Joint

7. +
=
Atlanto-occipital joint
Occipital bone
Atlas

8. THE OCCIPITAL BONE
 One of the skull bone.
 One in no.
 Occupies posterior and inferior parts of the skull.
 The inferior surface of condylar part shows occipital
condyl which articulates with superior articular facet
of atlas to form atlanto-occipital joint.

9. Fig: Inferior view of occipital bone
Basilar part
Occipital facet
Condylar part
Squamous part

10. ATLAS: First cervical vertebrae
How we will characterize ?
 body and spine is absent.
 two lateral masses joined by short anterior and
long posterior arch.
 arches gives the atlas ring like appearance.
 large transverse process pierced by foramen
transversarium.
 Superiorly lateral mass shows an elongated
concave facet which articulates with the
corresponding condyle of occipital bone.
 Inferiorly lateral masses shows a large oval facet
for articulation with the corresponding superior
articular facet of axis.

11. Fig: Superior view of atlas
Fig: Inferior view of atlas

12. A. Atlanto - Occipital joint
Articular surface:
It is articulation between atlas(1st cervical vertebrae)
and occipital bone(a skull bone), thus makes a pair of
condyloid joint .
atlanto-occipital joint
atlanto-axial joint
Fig: posterior view

13. Membrane/Capsule
Posterior
atlanto occipital membrane
Anterior
atlanto-occipital membrane
 Extends from anterior
arch of atlas to anterior
margin of foramen magnum.
 Extends from posterior
arch of atlas to posterior
margin of foramen magnum.
Capsule:
The capsule of the atlanto-occipital joint are attached
along the margin of the corresponding facet.
Type:
Synovial socket type joint i.e. ellipsoid.

14. Fig: Anterior atlanto-occipital membrane Fig: Anterior atlanto-occipital membrane
Posterior
arch of axis
Anterior
arch of axis
Ligamentum
nuche

15. Ligaments
 Anterior and posterior ligament: attached to upper and
lower border of body.
 Intertransverse ligament: medial side of lateral masses
 Ligamentum flava: anterior surface of upper border and lower
parts of laminae.
 Ligamentum nuche: tip of posterior tubercle.
 Lateral atlanto-axial joint
Interspinous ligament
Supraspinous ligment

16. Fig: ligaments attached to atlas and axis(median view)

17. Fig: ligaments attached to atlas(posterior view)

18. Muscles attached to atlas
Rectus capitis anterior: arises from front of lateral mass
Rectus capitis posterior minor: from posterior tubercle
Rectus capitis lateralis: arises from anterior part of transverse
process
Oblique capitis superior: arises from posterior part of transverse
process
Obique captis inferior: arises from inferior aspect of transverse
process.
Levator scapulae(some fibres): arises from lateral margin of
transverse process

19. Movements
 Flexion: 0 to 15 degree.
Muscle involved: longus capitis and rectus capitis anterior.
 Extension: 0 to 20 degree.
Muscle involved: rectus capitis posterior major, rectus
capitis posterior minor, obliqus captis superior and upper part of
trapezius
 Side bending: 5 degree on either side.
Muscle involved: rectus capitis lateralis, semispinalis
capitis, sternocleidomastoid and trapezius.
 Axial rotation: very less(8 degree on either side).

20. Lateral bending
Flexion Extension
Fig: Atlanto - Axial Joint movement

21. Fig: possible movements on atlanto-occipital and atlanto-axial joint

22. CLINICAL ANATOMY: ATLANTO-OCCIPITAL JOINT
 Occipitalization of atlas:
- atlas fuses with occipit
 Decalcification of atlas:
- caused by pharyngeal and retropharyngeal
inflamation.
 Prolapse of intervertebral disc:
- most often traumatic(usually 6th and 7th cervical
and upper lumbar prolase occurs).
 Oesteophyte formation in ‘luschka’s joint’:
- cervical nerve root compression.
- may cause distortion of vertebral artery
i.e vertebrobasilar insufficency .

23. Fig: occipitalization(degenrative changes)
Occipitalization

25. B. Atlanto - Axial Joint

26. AXIS: Second cervical vertebrae
How we will characterize
Presence of tooth like process projecting upward from the
body called “dense or odontoid”.
The dense represent the body of the atlas.
Small transverse process.
Superior surface of body is fused with dense.
Superior articular facet is large, flat and circular directed
upward and laterally
Inferior surface has a prominent downward projecting
anterior margin.
Inferior articular facet lies posterior to the transverse
process.
Deep and wide inferior vertebral notch inferiorly.
Thick and strong spine.

27. Fig: Superior view of axis

28. B. ATLANTO – AXIAL JOINT
Atlanto - Axial Joint
Medial
Atlanto - Axial Joint
Lateral
Atlanto - Axial Joint
 between the inferior
facet of atlas and the
superior facet of the axis.
 between dense and
anterior arch.
 between dense and
transverse ligament.

29. Fig: atlanto – axial joint

30. Fig: atlanto - axial joint

31. Ligaments
Capsular ligament:
- supports lateral lateral atlanto-axial joint
Anterior longitudnal ligament:
- lateral fibres supports lateral atlanto-axial joint.
Ligamentum flavum:
- supports lateral atlanto-axial joint.
Loose capsular ligament:
- supports medial atlanto-axial joint.
Transverse ligament:
- supports medial atlanto-axial joint.

32. Fig: atlanto - axial joint ligament

33. Movement
Rotation: takes around vertical plane.
Muscle involved: obliqus capitis inferior
rectus capitis posterior major
spleinus capitus
sternoclidomastoid.
Fig: atlanto - axial joint movement

35. CLINICAL ANATOMY: ATLANTO-AXIAL JOINT
Hangman’s fracture:
- fracture of pedicle of axis vertebrae
Odontoid process fracture:

36. YOUR QUERIES
PLEASE ?

37. HOPE……
YOU UTILISEDYOUR TIME AT RIGHT PLACE.

38. THANKYOU
FOR YOUR
ACTIVE PARTICIPATION
AND
KIND COLLABORATION.
- SHUBHAM SINGH