GENERAL INFORMATION
The splenius muscles, specifically the splenius capitis and splenius cervicis, are part of the superficial layer of the posterior neck muscles. They play an essential role in head and neck movement, particularly in rotation, flexion, and extension. Consequently, understanding these muscles is crucial for comprehending neck mechanics.
ORIGIN
The splenius capitis originates from the lower half of the ligamentum nuchae and the spinous processes of the seventh cervical and first three thoracic vertebrae. In contrast, the splenius cervicis originates from the spinous processes of the third to sixth thoracic vertebrae. Therefore, both muscles have distinct but closely related points of origin.
INSERTION POINT
The splenius capitis inserts onto the mastoid process of the temporal bone and the lateral third of the superior nuchal line. Meanwhile, the splenius cervicis inserts into the transverse processes of the first to third cervical vertebrae. Thus, these insertion points highlight the specific roles of each muscle in head and neck movement.
MAJOR ARTERIES
The deep cervical artery and the occipital artery primarily supply the splenius muscles. Consequently, these arteries ensure that the muscles receive adequate blood flow to perform their functions efficiently.
NEURAL INNERVATION
The posterior rami of the lower cervical nerves innervate the splenius muscles. Therefore, proper nerve function is vital for the activation and control of these muscles.
TRIGGER POINT
Trigger points for the splenius muscles can be found in the muscle belly. These points can be stimulated through manual pressure or massage to relieve pain. As a result, targeted therapy can significantly alleviate discomfort and improve muscle function.
CONCENTRIC FUNCTION
The splenius muscles extend the neck and head bilaterally. When acting unilaterally, they rotate and flex the neck to the same side. Thus, they are integral to various head and neck movements.
ECCENTRIC FUNCTION
The splenius muscles control the speed and direction of the neck’s lateral and rotational movement. They play a critical role in maintaining head and neck stability during these movements and are essential for coordinated and controlled actions.
ISOMETRIC FUNCTION
When the head and neck are static, the splenius muscles work isometrically to help stabilise the cervical spine. As a result, they provide essential support during various activities and maintain proper posture and alignment.
RELATED MUSCLES (SCIENTIFIC NAMES)
- Levator Scapulae: Elevates the scapula and assists in neck extension and rotation.
- Rhomboid Major: Retracts the scapula and supports upper back and neck posture.
- Rhomboid Minor: Works with the major to stabilise the shoulder and support the neck.
- Sternocleidomastoid: Assists in neck flexion, rotation, and lateral bending.
- Trapezius: Extends from the neck to the mid-back, supporting neck movements and shoulder mechanics.
ANTAGONIST MUSCLES
- Sternocleidomastoid: When the splenius muscles extend the head, this muscle acts to flex it.
- Scalene Muscles: These neck muscles oppose the splenius during various neck movements and support rib elevation during deep breaths.
COMMON INJURIES
- Neck strains and sprains: Common due to quick, unexpected neck movements or poor posture over time.
- Tension headaches: Arise from tightened splenius muscles, often related to stress or poor ergonomics.
- Myofascial pain syndrome: Persistent pain due to pressure on sensitive points in the splenius muscles.
EXERCISES
- Neck Tilts: Simple side tilts can significantly improve neck muscle tone and flexibility.
- Head Turns: Enhance neck mobility by rotating the head gently, which also aids in muscle relaxation.
- Shoulder Shrugs: These simple movements help release neck tension and build strength in the upper back.
- Yoga Neck Extensions: Incorporate gentle backbends to increase neck flexibility and reduce stiffness.
- Resistance Band Pulls: Strengthen the neck and upper back muscles effectively by pulling against resistance.
STRETCHES
- Lateral Neck Stretch: Reduces stiffness by elongating the muscles on the side of the neck.
- Chin Tuck and Release: Promotes better posture and relieves strain by stretching the neck.
- Gentle Rotation Stretch: Increases flexibility and eases the muscles around the neck.
- Forward Neck Stretch: Targets the splenius and other posterior neck muscles to relieve tension.
- Neck Extension Stretch: Helps to alleviate tightness in the front of the neck, balancing the muscle actions.
Incorporating these stretches and exercises into a daily routine can effectively enhance neck muscle strength, improve flexibility, and reduce the likelihood of injuries. Regular maintenance of neck health through these practices supports overall wellbeing and functional mobility.