Strap muscles: anatomy and function

The splenius muscles are two paired muscles at the back of the neck, which are considered part of the superficial layer of the intrinsic muscles of the back. They lie deeper than the trapezius muscle and form a "belt" of muscle fibers running obliquely upward and outward from the spine to the base of the skull and the upper cervical vertebrae. [1]

The splenial muscles include the splenius capitis (musculus splenius capitis) and the splenius cervicis (musculus splenius cervicis). In a practical sense, these are the muscles that help hold the head upright and allow for controlled rotation and tilt of the neck. [2]

Unlike the deep short muscles, which "adjust" micromovements between individual vertebrae, the splenial muscles often act as larger levers. They are involved in head and neck movements, and with prolonged static loading, they can become a source of myofascial pain. [3]

To understand the complaints, it's important to remember that pain associated with the splenial muscles doesn't necessarily have to be felt strictly at the point of strain. With myofascial pain syndrome, referred pain is possible in the back of the head, the crown, and sometimes in the area around the eye, which is often confused with primary headaches or eye problems. [4]

Table 1. Strap muscles in 1 minute

Muscle	Where is it located?	Basic movements	A common clinical scenario
Splenius capitis muscle	The posterolateral surface of the neck, towards the base of the skull	Extension of the head and neck, rotation and tilt to one side	Pain in the back of the head and top of the head when overloaded
The splenius muscle of the neck	The posterolateral surface of the neck, to the transverse processes of the upper cervical vertebrae	Neck extension, rotation and tilt to one side	Neck pain with limited head rotation

[5]

Anatomy of the splenial muscles: attachments, innervation, blood supply

The splenius capitis muscle typically originates from the spinous processes of the lower cervical and upper thoracic vertebrae and from the inferior portion of the nuchal ligament, and attaches to the mastoid process of the temporal bone and the superior nuchal line of the occipital bone. Because of this attachment, pain from overuse often "rises" upward to the occiput and parietal region. [6]

The splenius cervicis muscle typically originates from the spinous processes of the upper thoracic vertebrae and inserts on the transverse processes of the upper cervical vertebrae. The levels may vary slightly in different anatomical descriptions, but the functional idea is the same: the muscle connects the upper thoracic region to the cervical spine and helps control neck position. [7]

The splenial muscles are innervated by the posterior rami of the cervical spinal nerves. This is clinically important because pain in the splenial muscle area sometimes coexists with cervical radiculopathy, and then neurological symptoms in the arm are added to the muscle pain. [8]

The blood supply is provided by branches of the arteries of the posterior neck, including branches of the occipital and deep cervical arteries, as well as other regional branches, which are described in anatomical atlases. These details are rarely needed by the patient, but are important in injuries and interventions in the posterior neck area. [9]

Table 2. Anatomical "passport" table

Parameter	Splenius capitis muscle	The splenius muscle of the neck
Typical beginning	Spinous processes of the lower cervical and upper thoracic vertebrae, nuchal ligament	Spinous processes of the upper thoracic vertebrae
Typical attachment	Mastoid process, region of the superior nuchal line	Transverse processes of the upper cervical vertebrae
Innervation	Posterior branches of the cervical nerves	Posterior branches of the cervical nerves
General role	Head and neck movements	Neck movements, position control

[10]

Function and biomechanics: How the splenial muscles move and stabilize the neck

When contracted bilaterally, the splenius muscles extend the cervical spine, helping to support the head and return it from a forward bend. This is especially noticeable during prolonged sitting, when the head "slips" forward and the posterior muscles are forced to work longer than usual. [11]

When contracted unilaterally, the splenius capitis muscle rotates and tilts the head. The splenius cervicis muscle similarly rotates and tilts the cervical spine. Therefore, overuse often manifests as limited head rotation and pain when attempting to look over the shoulder. [12]

The cervical muscles do not work in isolation, but in conjunction with other muscles of the neck and shoulder girdle. If the endurance of the muscles stabilizing the scapula and thoracic region is weakened, the load can be redistributed to the upper quadrant, and then the posterior cervical muscles experience chronic "static work." [13]

In terms of rehabilitation, this explains why a lasting effect is often achieved not only by local stretching of the painful area, but also by a program of exercises for neck mobility, neck muscle endurance, and strengthening of the scapulothoracic complex. Such approaches are directly reflected in clinical guidelines for neck pain. [14]

Table 3. Movements and typical complaints

Action	What work do the splenial muscles perform?	What does it feel like to be overloaded?
Neck extension	"Head support" against gravity	A nagging pain in the back of the head, neck fatigue in the evening
Turn in your direction	Head or neck rotation	Pain and limited turning ability, especially when driving
Tilt to your side	Lateroflexion	Pain in the side of the neck and at the base of the skull
Static pose holding	Long-term tension without movement	Stiffness after sleep or after working at the computer

[15]

Pain and trigger points: myofascial pain syndrome and referred pain

Myofascial pain syndrome is described as regional musculoskeletal pain associated with tender, sensitive areas within tense muscle bands. These areas are often referred to as trigger points and can cause both localized and referred pain. [16]

For the splenius capitis muscle, clinical descriptions most often mention pain in the back of the head and the top of the head, with possible radiating pain to the temple or behind the eye. It's important to interpret this carefully: this presentation may be muscle-related, but it must be assessed in the context of other symptoms to avoid overlooking migraine, cervicogenic headache, or occipital neuralgia. [17]

The splenius cervicis muscle is most often described as pain at the base of the neck and in the posterolateral region, sometimes radiating to the back of the head. This may be accompanied by severe stiffness and a feeling of "jamming" when turning the head, especially after sleep or after prolonged static work.

The modern approach to treating myofascial pain is typically combined: load management, exercises, movement training, and sometimes acupressure, as indicated. Dry needling and trigger point injections can provide short-term relief in some people, but the effect depends on the protocol and is always assessed in conjunction with active rehabilitation. [19]

Table 4. Typical pain areas and what to check further

Picture of pain	Possible connection with the strap muscles	What is important to exclude
Back of the head, crown	Splenius capitis, posterior neck muscles	Cervicogenic headache, occipital neuralgia
"Behind the eye", temporal region	Referred pain is possible with a myofascial component	Migraine, ophthalmological causes, vascular symptoms
Base of the neck, posterolateral zone	Splenius cervicis muscle, general mechanical pain	Cervical radiculopathy with arm symptoms
Stiffness after sleep	Overload, awkward posture, hypertonicity	Inflammatory causes of prolonged morning stiffness and systemic symptoms

[20]

Differential diagnosis and red flags

Pain in the occipital region and neck is often benign and musculoskeletal, but clinical practice requires excluding scenarios where delay is dangerous. Therefore, the initial assessment always considers systemic symptoms, trauma, progressive neurological signs, and an atypical course. [21]

If pain radiates into the arm, accompanied by numbness, decreased strength, or altered reflexes, cervical radiculopathy is considered. If signs of spinal cord damage appear, such as gait disturbance, clumsiness of the hands, or urinary problems, this is a reason for urgent evaluation, as spinal cord compression may be present. [22]

If the pain in the back of the head is shooting and triggered by contact with the occipital nerves, occipital neuralgia is considered. It can mimic other types of headache, so typical symptoms are helpful: paroxysmal onset, pain along the nerve, and response to a diagnostic nerve block, as indicated. [23]

A separate, rare, but critically important scenario is cervical artery dissection. It can begin as a severe headache or neck pain and then lead to symptoms of ischemic stroke, so sudden, unusual pain, especially after a neck injury or sudden movement, requires immediate medical evaluation. [24]

Table 5. When an urgent medical assessment is needed

Sign	Why is this important?
Weakness in an arm or leg, sensory disturbances, clumsiness of the hands	Possible damage to the nerve root or spinal cord
Gait disturbance, severe clumsiness, problems with urination	Signs of possible cervical myelopathy
Fever, night sweats, unexplained weight loss	Risk of infection or tumor process
Recent significant neck injury	Risk of fracture or instability
Sudden, unusual, severe headache or neck pain, especially with neurological symptoms	Risk of vascular cause, including dissection

[25]

Diagnosis and treatment: a modern practical approach

For typical mechanical pain without red flags, the basis of diagnosis is physical examination: assessment of neck range of motion, pain provocation, muscle endurance, scapular function, and neurological screening if arm symptoms are present. Imaging is generally not necessary for everyone, but is indicated, particularly if there is a neurological deficit or deterioration. [26]

The best evidence-based treatment for mechanical neck pain typically includes active interventions: mobility exercises, endurance training for the neck and shoulder girdle muscles, and manual techniques when indicated, often including the thoracic spine. Clinical guidelines emphasize the value of a combination of exercise and manual therapy, as well as strengthening the scapulothoracic muscles. [27]

Trigger point-targeted therapies are considered adjunctive rather than exclusive therapy. Dry needling has been shown in meta-analyses to improve pain and function in the short and medium term in some patients with chronic neck pain, but the results are protocol-dependent and the long-term effects are more inconclusive. [28]

Trigger point injections have also been studied, but data on comparative effectiveness and optimal solutions are mixed. A systematic review of chronic myofascial neck and back pain outlines the need for careful benefit-risk assessment and highlights the variability of outcomes, so such interventions are generally considered for persistent pain, alongside comprehensive rehabilitation, and under specialist guidance. [29]

Table 6. Treatment tactics by stages

Stage	What to do	Target
1-7 days for typical mechanical pain	Dosed activity, gentle mobilization, heat as tolerated, sleep and work posture	Reducing pain without immobilization
2-6 weeks	Exercises for neck muscle mobility and endurance, strengthening the shoulder girdle and shoulder blades, and movement training	Steady improvement in function
For severe myofascial pain	Point methods as a supplement: manual techniques, dry needling according to indications	Reduced pain sensitivity, window for exercise
For neurological symptoms or worsening	Neurological assessment, imaging as indicated, specialized treatment	Elimination of a dangerous cause
In case of relapses	Review of load, ergonomics and exercise program	Prevention of recurrences

[30]

Table 7. Example of a safe home routine for 10-12 minutes

Block	Example	Dosage
Unloading	Drop your shoulders, soft diaphragmatic breathing	2 minutes
Mobility	Head rotations within a comfortable range, without increasing pain	2 sets of 8-10 reps
Soft stretching	Stretching of the posterior lateral surface of the neck without sharp pain	2 sets of 20-30 seconds
Endurance	Isometric head hold in neutral position, light resistance with palm	3 sets of 8-10 seconds
Shoulder blades	Scapular retraction without raising the shoulders	2 sets of 10-12 reps

[31]