Cervical spine; Movements and Biomechanics
Extension - Axis
Coronal
Lateral flexion - Plane
Coronal
Lower cervical spine •Flexion - Axis
Coronal
Upper cervical spine • C1 - C2 - How many degrees of flexion & extension are available between these bones
Few degrees only
Upper cervical spine • C0 - C1 How many degrees of rotation are available between these bones
Few degrees only - minimal
Upper cervical spine • C0 - C1 - What movements are available between these bones?
Flexion, extension, lateral flexion and rotation
Upper cervical spine • C1 - C2 - What movements are available between these bones?
Mainly rotation with a few degrees of flexion and extension.
Rotation - Which part of the cervical offers the
Most of the total rotation is contributed by C1/2 (47°)
Upper cervical spine • C1 - C2 -Describe how the bones move in order to facilitate flexion & extension
The lateral mass of the atlas rolls and slides on the superior articular facet of the axis; anteriorly for flexion and posteriorly for extension.
Rotation - Axis
Vertical
Lower cervical spine • Flexion a) Describe what happens to cervical vertebrae during this movement. b) State what happens to the joint space anteriorly + posteriorly
a) The superior vertebral body tilts and slides anteriorly on the sub-adjacent segment - Thus causing the inferior facet of the vertebra to move superiorly + anteriorly. b) The anterior space becomes compressed, whilst the joint space widens posteriorly
Extension a) Describe what happens to cervical vertebrae during this movement. b) State what happens to the joint space anteriorly + posteriorly
a) The superior vertebral body tilts and slides posteriorly on the sub-adjacent segment - Thus causing the inferior facet of the vertebra to move interiorly + posteriorly. b) The posterior space becomes compressed, whilst the joint space widens anteriorly
Lower cervical spine • Extension - What is the total range of flexion available?
approximately 85°
Lateral flexion - At which joints does this movement occur?
1. Atlanto-occipital 2. Intervertebral (coupled with rotation)
Lateral flexion - Describe what happens to cervical vertebrae during this movement.
1. The inferior articular processes that are ipsilateral to the direction of movement, glides inferiorly, posteriorly and translates medially on the superior process of the vertebra below. 2. The inferior articular processes that are contralateral to direction of movement moves anteriorly, superiorly and translates laterally - Thus lateral flexion and rotation occur on the same side
Upper cervical spine • C1 - C2 - Describe how the bones move in order to facilitate rotation
- The anterior arch and transverse ligament pivot around the odontoid process. - The lateral masses of the atlas glide over the articular surface of the axis; 1) the one contralateral to the direction of movement moves anteriorly 2) The one ipsilateral to the direction of movement moves posteriorly
Lateral flexion - Normal AROM
0 - 45°
Rotation - Normal AROM
0 - 60°
Flexion - Normal AROM
0 to 45 - 50°
Rotation - Describe what happens to cervical vertebrae during this movement.
1. The inferior articular processes that are ipsilateral to the direction of movement, glides inferiorly, posteriorly and translates medially on the superior process of the vertebra below. 2. The inferior articular processes that are contralateral to direction of movement moves anteriorly, superiorly and translates laterally - Thus rotation and lateral flexion occur on the same side
Upper cervical spine • C0 - C1 How many degrees of flexion and extension is available between these bones?
20°
Upper cervical spine • C1 - C2 - How many degrees of rotation are available between these bones
45° on each side. - Head and C1 move as a unit.
Upper cervical spine • C0 - C1 How many degrees of lateral flexion is available between these bones?
8°
Lower cervical spine • Flexion - What is the total range of flexion available?
Approximately 25°
Rotation - At which joints does this movement occur?
Atlanto-occipital Intervertebral (coupled with lateral flexion)
What is a coupled movement?
Motions that are not in the principal direction of the applied load Inherently coupled to the principal motion i.e. rotation or translation of a vertebral body about one axis is consistently associated with rotation/translation of same VB about another axis E.g. loading that produces left lateral bending can also produce axial rotation and flexion Axial rotation and flexion are coupled to the lateral bending and in the healthy spine these motions cannot be separated
Extension - Plane
Saggital
Lateral flexion - Axis
Saggital
Lower cervical spine •Flexion - Plane
Saggital
Upper cervical spine • C0 - C1 Describe how the bones move in order to facilitate flexion
The occipital condyles move backwards on the lateral masses and the space between the bones increases posteriorly
Upper cervical spine • C0 - C1 Describe how the bones move in order to facilitate extension
The occipital condyles move forwards on the lateral masses and the space between the bones increases anteriorly
Upper cervical spine • C0 - C1 Describe how the bones move in order to facilitate lateral flexion
The occipital condyles slip towards to direction of movement so it moves towards the midline
Extension - Normal limiting factors
The tension in the following structures limit this movement: 1. The anterior longitudinal ligament 2. The anterior neck muscles 3. The anterior fibres of the annulus fibrosis 4. The impact of the superior 5. The bony contact between the spinous processes
Lower cervical spine •Flexion - Normal limiting factors
The tension in the following structures limits this movement: 1. Facet joint capsule 2. Posterior longitudinal ligament 3. Ligamentum nuchae 4. Ligamentum flavum 5. Posterior neck muscles 6. Posterior fibers of annulus fibrosis
Lateral flexion - Normal limiting factors
The tension in the following structures limits this movement: 1. The contralateral fibers of the annulus fibrosis 2. The contralateral facet joints 3. The contralateral alar ligament
Rotation - Normal limiting factors
The tension in the following structures limits this movement: 1. The ipsilateral alar ligament
Rotation - Plane
Transverse
