Last Updated on February 27, 2025
Cervical spine movements are complex and result from the interplay of individual vertebral motion. The cervical spine functions to stabilize and maintain the head in position as required for various tasks. It protects the cervical spinal cord and contributes to the balancing function of the body. The muscles surrounding the neck participate in swallowing and respiration.
The cervical spine movements allow a large range for the head to scan the surroundings and gauge the adjustments required for interaction.
There are six cervical spine movements possible in the normal range of motion of the cervical spine. These are
- Flexion- A movement by which the chin attempts to touch the chest.
- Extension- A movement in the opposite direction of flexion
- Lateral Flexion- This movement allows you to tilt your neck as if touching the ear to your shoulder. The movement is equal on both sides.
- Rotation- Rotation is the movement that we use to look over our shoulders or look back. The movement is equal on either side.
Cervical Spine Movements – Normal Range
The normal cervical range of motion is
- Flexion – 80 to 90 degrees
- Extension – 70 degrees
- Lateral flexion – 20 to 45 degrees on both sides
- Rotation – up to 90° of rotation to both sides.
In normal daily use, the movements are hardly uniplanar as outlined above.
Normal Kinematics of the Upper Cervical Spine
Both flexion and extension cervical spine movements are reported to be initiated in the lower cervical spine.
The first cervical vertebra, the atlas, articulates with the occipital condyles, and its primary motions are flexion and extension. Normal flexion to hyperextension at the atlanto-occipital joint range is 15 to 20 degrees. The rest is contributed by lower vertebrae.
Rotation and lateral flexion between the occiput and atlas are not possible due to the depth of the atlantal sockets. These movements occur on the atlantoaxial joint [C1-C2].
The C1-C2 motion segment accounts for 50% of the rotation in the cervical spine.
The normal ranges of rotation of C1 on C2 are reported to be 50° to each side. Rotation of the atlas on the axis does not occur without a small degree of extension and lateral flexion and sometimes flexion.
Cervical spine flexion and extension often create motion in the opposite direction in the atlas. Thus, when the cervical spine is flexing, the atlas extends, and when the cervical spine extends, the atlas flexes.
The orientation of the cervical vertebral bodies of the mid to lower cervical column allows for rotation and flexion movements but is resistant to lateral flexion. Lateral flexion is possible in the cervical column but only due to coupled rotational movement in each segment to that side.
Measurement of Cervical Spine Range of Motion
The patient sits upright on a chair with their back against the chair, arms on the side, and feet on the floor with eyes looking at a distance at eye-level to keep the neck straight. This is considered to be a zero position.
- Flexion: The patient is asked to bring their chin towards their chest as if nodding. Normally patient can touch his chest with his chin.
- Extension: Ask the patient to look upwards as far as possible, until full extension of the neck is achieved.
- Lateral flexion: The patient to tilts the head laterally to the left, without rotating the head, and keeping the shoulder fixed to bring bring ear as close as possible to the shoulders. Repeat the procedure for the opposite side.
- Rotation: While the examiner stabilizes the shoulder, the patient rotates his/her head to the left as far as possible without tilting or tipping his/her head.
During clinical examination, much of the work is done by eyeballing. However, measuring the angle of cervical spine movements by eyeballing is a crude method, observer-dependent and not objective.
Other methods that are used to measure cervical spine movements are
- Tape Measure: A measuring tape measures changes in the distance of the reference point of cervical motion (chin) from a fixed body part (lower sternal notch). However, it is not suitable for measuring the degree of motion
- Inclinometer: It measures the difference between distinct angles of the head during cervical spine movements. it is reliable but the validity is in question.
- Goniometer: A Goniometer is an instrument that is used for accurate measurement of the range of motion between two joints. However, it requires the use of both hands to operate the instrument and hence the examiner is not able to stabilize the neck while checking the cervical spine movement range.
- Cervical Range of Motion Device: CROM device uses goniometers and a compass mounted on a rigid headgear. As such, its position remains consistent and allows for accurate measurement of the head and neck range of motion.
Muscles Used in Cervical Spine Movements
Different sets of muscles are employed in different cervical spine movements. There would be differences in the contribution of muscles at different stages of one movement. This brings in the smoothness of movements and efficient use of energy in such complex and interdependent moving parts.
Here are different sets of muscles that participate in cervical spine movements.
Flexor Muscles
- Rectus capitis anterior
- Longus colli
- Longus capitis
- Anterior scalene
- Sternocleidomastoid
- Rectus capitis lateralis
Extensor Muscles
- Obliquus capitis superior
- Obliquus capitis inferior
- Rectus capitis posterior major
- Rectus capitis posterior minor
- Iliocostal cervicis
- Trapezius
- Splenius cervicis
- Splenius capitis
- Spinalis capitis
- Longissimus capitis
Lateral Flexors
- Muscle
- Splenius cervicis
- Splenius capitis
- Sternocleidomastoid
- Anterior scalene
- Middle scalene
- Posterior scalene
- Trapezius
- Rectus capitis lateralis
- Spinalis capitis
- Longissimus capitis
Rotators Muscles
- Rectus capitis posterior major
- Rectus capitis posterior major
- Sternocleidomastoid
- Splenius capitis
- Splenius cervicis
- Spinalis capitis
References
- de Koning CHP, van den Heuvel SP, Staal JB, Smits-Engelsman BCM, Hendriks EJM. Clinimetric evaluation of active range of motion measures in patients with non-specific neck pain: a systematic review. Eur Spine J. 2008;17(7):905–921. doi: 10.1007/s00586-008-0656-3. [PubMed]
- Yee Won YK, Mohd Latip HF, Abdul Aziz MS. The reliability and validity on measuring tool of cervical range of motion: a review. Sports Med Inj Care J. 2019;1(1):1–4. doi: 10.24966/SMIC-8829/100001. [DOI]
