GENERAL INFORMATION
The semispinalis capitis is a deep and intrinsic muscle of the back situated in the upper part of the neck. It plays a crucial role in the movement as well as stabilisation of the head and neck.
ORIGIN
The semispinalis capitis originates from the transverse processes of the upper thoracic vertebrae (T1-T6) and the articular processes of the lower cervical vertebrae (C4-C7). Additionally, these origins provide the muscle with the leverage needed for its function.
INSERTION POINT
It inserts into the area between the superior and inferior nuchal lines on the occipital bone of the skull. Consequently, this insertion allows the semispinalis capitis to exert its effects on head as well as neck movements.
MAJOR ARTERIES
The major arteries supplying the semispinalis capitis include:
- Occipital artery
- Deep cervical artery
These arteries ensure adequate blood flow as well as oxygen supply to the muscle, which is essential for its proper function.
NEURAL INNERVATION
The neural innervation of the semispinalis capitis is provided by:
- Greater occipital nerve (C2)
- Third cervical nerve (C3)
Thus, these nerves facilitate the control as well as sensory feedback necessary for the muscle’s activities.
TRIGGER POINT
Common trigger points in the semispinalis capitis can cause tension headaches and pain radiating from the back of the head to the top of the skull. Therefore, identifying and treating these trigger points can be crucial for managing related pain and discomfort.
CONCENTRIC FUNCTION
The semispinalis capitis performs concentric contractions to:
- Extend the head and neck
- Rotate the head and neck to the opposite side
These actions are essential for various movements and activities involving the head and neck.
ECCENTRIC FUNCTION
The muscle also performs eccentric contractions to:
- Control flexion of the head and neck
- Regulate opposite side rotation of the head and neck
Consequently, these functions help stabilise and decelerate movements.
ISOMETRIC FUNCTION
The semispinalis capitis performs isometric contractions to:
- Stabilize the head and neck during various movements
- Maintain posture by supporting the cervical spine
As a result, these contractions are crucial for postural control and stability.
RELATED MUSCLE-SCIENTIFIC NAMES
- Splenius Capitis: Works synergistically to extend and rotate the head.
- Longissimus Capitis: Assists in head extension and lateral flexion.
- Trapezius: Supports neck movements and upper back stability.
- Sternocleidomastoid: Acts in head rotation and flexion, providing balance.
- Levator Scapulae: Elevates the scapula, aiding in neck and shoulder movements.
ANTAGONIST
- Sternocleidomastoid: Acts mainly in flexing the neck, opposing the semispinalis capitis.
- Scalenes: Involved in flexing and slightly rotating the neck, opposing extension.
- Longus Capitis: Flexes the head and counteracting the backward motion.
- Longus Colli: Supports the neck flexion, providing an antagonistic role to extension.
COMMON INJURIES
- Muscle strain: Common from overextension or sudden movements.
- Tension headaches: Often stem from tightness in this muscle.
- Cervical facet joint dysfunction: Results from wear or injury affecting neck motion.
- Myofascial pain syndrome: Trigger points in this muscle can cause persistent pain.
EXERCISES
- Neck Extension: Sit upright and gently tilt your head back; hold, then return. Repeat ten times for flexibility and strength.
- Resistance Band Neck Extension: Use a band for resistance; extend the neck, hold, and release. To strengthen, do three sets of 10 reps.
- Prone Neck Extension: Lie face down, lift your head to align with your spine, hold, and lower. For endurance, do three sets of 12 reps.
- Isometric Neck Extension: Sit straight, press your head back into your hands, and hold for 5-10 seconds. For stability, perform three sets of 10 reps.
- Dynamic Neck Tilt: Gently tilt head side to side, enhancing muscle function and neck mobility.
STRETCHES
- Chin Tuck Stretch: Tuck the chin towards the chest, hold for 20-30 seconds, and relax. Repeat three times to reduce neck tension.
- Upper Trapezius Stretch: Gently pull the head towards each shoulder and hold each side for 30 seconds to loosen tight muscles.
- Levator Scapulae Stretch: Tilt head forward to each side, enhancing flexibility and easing muscle stiffness.
- Seated Neck Release: Anchor one hand to the chair, tilt the head away as well as hold for 20-30 seconds for a deep stretch. Repeat on both sides.
- Forward Neck Bend: Gently bend the neck forward, hold for a few seconds, and release to improve muscle elasticity and relaxation.
Incorporating these exercises and stretches can greatly improve the strength, flexibility, and overall health of the semispinalis capitis, aiding in better posture and reducing the risk of neck-related ailments.