Muscle:Splenius Cervicis

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Splenius cervicis is a deep posterior cervical muscle whose trigger points (TrPs) produce a distinctive cluster of symptoms: diffuse intracranial pain referred to the back of the eye, ipsilateral blurring of near vision, and — in its lower TrP — pain at the angle of the neck. It is a frequent and underrecognised source of pain in patients following whiplash and in those presenting with "stiff neck."

Because it lies almost entirely beneath the trapezius and is crossed by the levator scapulae, it is not readily palpable from behind, and its TrP involvement often only becomes apparent after TrPs in the levator scapulae have been inactivated.

Contents

Anatomy

The splenius cervicis lies lateral and caudal to the splenius capitis. Like the capitis, it attaches below in the midline to the spinous processes; the cervicis fastens from T₃ to T₆ vertebrae. The muscle connects above to the posterior tubercles on the transverse processes of the upper two or three cervical vertebrae.

On these posterior tubercles, the splenius cervicis forms the most posterior of a triple attachment with the levator scapulae in the middle and the scalenus medius in front.

Bilaterally, the paired splenius cervicis and splenius capitis muscles each form a "V" shape. The trapezius muscle covers much of both splenii.

Primary actions: Ipsilateral rotation and extension of the cervical spine when acting unilaterally; bilateral contraction causes extension of the neck. A significant lateral flexion function is highly questionable.

Innervation: Lateral branches of the dorsal primary divisions of spinal nerves C₂–C₄, frequently also C₁, sometimes C₅, and rarely C₆.

Main synergists (extension): Posterior cervical group as a whole, especially semispinalis capitis and cervicis.

Synergists (ipsilateral rotation): Ipsilateral levator scapulae; contralateral upper trapezius, semispinalis cervicis, deep spinal rotator muscles, sternocleidomastoid.

Antagonists (rotation): Contralateral levator scapulae, ipsilateral upper trapezius, semispinalis cervicis, deep spinal rotators, sternocleidomastoid.

Referred Pain Patterns

Upper TrP — Orbital and Intracranial Referral

A TrP at the upper end of the splenius cervicis (pressure applied to the tender craniad musculotendinous junctions) refers a diffuse pain through the inside of the head that focuses strongly behind the eye on the same side — an "ache inside the skull."

This intracranial quality with posterior-ocular focus is the defining, must-have feature of splenius cervicis upper TrP involvement and distinguishes it from the vertex referral of splenius capitis. The pain seems to shoot through the inside of the head to the back of the eye (represented by a dash line and arrow in the classic illustration).

Lower TrP — Angle of the Neck

A TrP in the lower portion of the splenius cervicis (central, mid-muscle location) refers pain upward and to the base of the neck — the pattern lying in the upper part of the pain pattern of the levator scapulae but with some spread medially.

The lower TrP refers pain to the angle of the neck on the same side (figure on the right in Fig. 15.1B of the source volume).

Vision Disturbance

An upper splenius cervicis TrP may cause blurring of near vision in the ipsilateral eye, without dizziness or conjunctivitis. This symptom sometimes resolves immediately and completely with inactivation of the responsible TrP, making it a clinically important diagnostic marker when present.

Overlapping Patterns

The lower TrP pattern overlaps substantially with the upper portion of the levator scapulae referral pattern. At least seven other head and neck muscles have similar or overlapping pain patterns:

Activation and Perpetuating Factors

Postural Factors

Postural stresses that overload extension or rotation of the head and neck are the most common initiating and perpetuating mechanism:

  • Working at a desk with the head turned to one side and projected forward to view a display screen or documents
  • Bird-watching through binoculars while seated in a position that extends the neck to compensate for a strong thoracic kyphosis
  • Assuming a similar posture of head and neck extension while playing certain musical instruments (e.g. accordion)
  • Falling asleep with the head and neck bent in a crooked position — such as with the head on the armrest of a sofa without an adequate pillow

Trifocal eyeglasses should not be worn by patients susceptible to splenius cervicis TrPs, as adjustments in neck posture needed to see through the middle section of trifocal lenses may perpetuate TrP activity.

Impact and Activity Stress

  • Whiplash (acceleration-deceleration injury): A significant number of patients with head and neck pain following motor vehicle accidents have active splenius cervicis TrPs; the myofascial TrP component is frequently overlooked in favour of diagnoses that do not address the tissue-source of the patient's symptoms.
  • Sudden overload — pulling on a rope while rotating or projecting the head forward
  • Pulling excessive weight on exercise equipment pulleys, particularly when the head is rotated or projected forward

Environmental Factors

A cold air conditioner or cool draft blowing on the exposed neck, together with muscular fatigue, greatly increases the likelihood of TrP activation. Environmental stress acting on both splenius cervicis and levator scapulae TrPs may occur with marked skin cooling, especially when the muscles are tired.

Clinical Examination

Range of Motion Assessment

Patient examination reveals:

  • Moderate restriction of passive head and neck flexion and rotation to the opposite side
  • Painful restriction of active head and neck rotation to the same side
  • Less restriction of rotation than when only levator scapulae is involved — an important distinguishing feature
  • Simultaneous TrP activity in both levator scapulae and splenius cervicis may almost completely block active head rotation to that side

Splenius cervicis involvement may become apparent only after residual pain and stiffness following elimination of TrP activity in the levator scapulae.

Trigger Point Examination

The splenius cervicis is not readily palpable. From behind, all of it is covered by the upper or middle trapezius muscle; only a small patch is not covered by the splenius capitis and/or the rhomboid minor posteriorly, or by the levator scapulae laterally.

Best approach — from the side, through or around the levator scapulae:

If the skin and subcutaneous tissues are sufficiently mobile, the operator slides the palpating finger anterior to the free border of the upper trapezius at approximately the level of the C₇ spinous process, to and beyond the levator scapulae muscle.

  • If the levator scapulae is not tender but additional pressure directed medially toward the spine is painful, this is likely a splenius cervicis TrP that can be tested for reproduction of the patient's pain complaint
  • In patients with mobile connective tissue, the taut bands may be palpable running caudad diagonally from lateral to medial
  • The levator scapulae can be felt to contract with shoulder elevation; the splenius cervicis contracts with neck extension — a useful distinguishing manoeuvre

Posterior approach:

Digital pressure to splenius cervicis TrPs is applied mid-muscle at approximately 2 cm lateral to the spine at approximately the level of the C₇ spinous process, which is just above the angle of the neck.

Tenderness deep to the trapezius may be from either splenius cervicis or levator scapulae TrPs. If straight flexion of just the neck (increasing tension chiefly on the splenius cervicis fibres) increases the sensitivity of the tenderness, it is more likely from splenius cervicis TrPs.

Elongation test:

Both splenius capitis and splenius cervicis are elongated by neck flexion, but only the splenius capitis is further elongated by flexion of the head on the cervical spine — useful for differentiating the two muscles during examination.

Differential Diagnosis

Condition Distinguishing features
Levator scapulae TrPs Lower splenius cervicis TrP pattern overlaps substantially with the upper levator scapulae pattern; splenius cervicis involvement often only becomes apparent after levator TrPs are inactivated; levator contracts with shoulder elevation, splenius cervicis with neck extension
Splenius capitis TrPs Splenius capitis refers to the vertex on the same side; splenius cervicis upper TrP refers diffusely through the inside of the head to the back of the eye — a distinguishing intracranial quality; both are elongated by neck flexion, but only splenius capitis is further elongated by head-on-cervical-spine flexion
Semispinalis cervicis, suboccipital TrPs All can produce overlapping occipital and upper cervical pain; differential palpation of taut bands in each muscle required; splenius cervicis location is lateral and more superficial than semispinalis cervicis
Cervicogenic headache / occipital neuralgia Splenius cervicis TrPs are a primary unrecognised source; myofascial pain lacks the lancinating neuralgic quality; pain is reproduced by muscle palpation
Splenius cervicis TrP component is frequently overlooked; anterior neck and chest muscles (SCM, pectoralis minor) must also be examined; recovery often requires inactivation of TrPs in anterior neck and chest muscles before posterior muscles fully resolve
Spasmodic torticollis (wry neck) Neurological condition with paroxysmal or clonic contractions and muscle hypertrophy with fibrotic change; myofascial "stiff neck" has steady resistance without paroxysmal contractions and no hypertrophy
Articular dysfunction C₄–C₅ Dysfunctions at C₄ and C₅ are likely with splenius cervicis TrPs; with TrPs in the splenii, multiple and varied cervical articular dysfunctions are frequently found; TrP inactivation is necessary alongside articular treatment

Treatment

Trigger Point Release

The splenius capitis and splenius cervicis are generally released together with their synergists as part of one treatment unit. Tightness in one muscle may prevent full stretch of the parallel synergistic units.

Spray and stretch technique:

  1. Patient seated with shoulder girdle horizontal (pelvis levelled if necessary)
  2. Head rotated 20–30° away from the involved splenii, and gently flexed toward the opposite side
  3. Vapocoolant spray applied in an up-stroke pattern over the muscles and occiput to the vertex; for the splenius cervicis, the spray should also cover the angle of the shoulder and the lateral aspect of the head as far forward as the eye (protect the eye from spray)
  4. Operator grasps the head between both hands, applies upward traction, and gently further flexes and rotates the head toward the opposite side to take up slack
  5. Patient simultaneously looks down, slowly exhales, and may actively tilt the head in the direction of the stretch (reciprocal inhibition)
  6. Hot pack applied promptly over treated muscles

TrPs also respond to pressure release and deep massage.

If the patient is being treated for a "stiff neck," any TrPs in the levator scapulae should be injected at the same time as those in the splenius cervicis.

Trigger Point Injection

The more caudal splenius cervicis trigger points usually respond well to injection therapy.

Caution: During injection, a few patients have fainted as a result of the strong autonomic stimulus associated with release of this TrP. This fainting usually followed multiple large twitch responses with visible deviation of the head in the direction of the twitch, suggesting the syncope relates to altered vestibular input. When the head moves, it is likely that fibres of the splenius capitis and splenius cervicis contract together.

Corrective Actions

Postural:

  • Keep head and neck erect, thoracic spine extended; minimise excessive twisting and turning
  • Monitor/display screen directly in front of the body, at an angle that encourages erect posture; documents at the same level as the monitor, not flat on the desk to one side
  • Do not wear trifocal eyeglasses if susceptible to splenius cervicis TrPs; reflections on eyeglasses and contact lenses can be managed by changing the relative position of the light source or using tinted lenses
  • Body asymmetry (lower limb length inequality, small hemipelvis) should be corrected
  • Sleep with the head and neck in a neutral position with appropriate pillow support

Environmental:

  • Keep the neck warm by sleeping in a high-necked sleeping garment, wearing a turtleneck sweater or scarf during waking hours, and avoiding cold drafts

Exercise therapy:

  • Patient releases tightness by reaching up and gently flexing and turning the head through the full range of flexion, extension, and rotation — best done sitting on a stool or standing in a warm shower using postisometric relaxation
  • After release, the head and neck are moved slowly and gently through the full range three times
  • If adjacent fibres remain sore and taut, the exercise is repeated with slightly different head positions
  • Avoid "head rolling" (swinging the head around the full range of motion) — this seriously overloads adjacent lines of taut muscle fibres and can worsen the condition

Satellite Trigger Points

  • Levator scapulae — most consistently co-active; active TrPs rarely appear in the splenii alone; the levator scapulae and splenius cervicis share posterior tubercle attachments at the upper cervical transverse processes
  • Splenius capitis — treated together as one functional unit
  • Semispinalis capitis — primary synergist for extension
  • Semispinalis cervicis — primary synergist for extension
  • Upper trapezius — synergist for contralateral rotation
  • Sternocleidomastoid — synergist for rotation; frequently co-involved after whiplash

References

  • Travell JG, Simons DG. Myofascial Pain and Dysfunction: The Trigger Point Manual, Volume 1: The Upper Half of Body. 2nd ed. Baltimore: Williams & Wilkins; 1999. Chapter 15.
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