Muscle:Semispinalis Capitis
Semispinalis capitis is a long, nearly vertical posterior cervical muscle whose trigger points (TrPs) produce a band-like headache that encircles the head halfway, reaching maximum intensity in the temporal region and continuing forward over the eye. It is one of the most common muscular sources of tension-type and cervicogenic headache, and its taut bands are responsible for the most clinically important entrapment of the greater occipital nerve.
Because it provides a checkrein function during even slight neck flexion — the dominant posture of modern desk-based work — it is chronically strained by reading, writing, computing, and sewing with a forward head posture. Semispinalis capitis TrPs are frequently satellites of key TrPs in either the upper trapezius or the splenius capitis; elimination of those key TrPs often inactivates the semispinalis capitis without direct treatment.
Contents
- 1 Anatomy
- 2 Referred Pain Patterns
- 3 Activation and Perpetuating Factors
- 4 Clinical Examination
- 5 Differential Diagnosis
- 6 Treatment
- 7 Satellite Trigger Points
- 8 Related Pages
- 9 References
Anatomy
The semispinalis capitis attaches below to the articular processes of cervical vertebrae C₄ to C₆ and to the transverse processes of thoracic vertebrae T₁ to T₆, and sometimes T₇. Above, it attaches to the occiput between the superior and inferior nuchal lines.
The muscle is usually divided by a tendinous inscription at the level of C₆. Less frequently there is a tendinous inscription at C₂, most marked in the medial fibres from the thoracic vertebrae. These inscriptions can divide the muscle so there can be three endplate zones, one in the middle of each third:
- Upper third endplate zone: nearly transverse line at the suboccipital level
- Middle third endplate zone: approximately C₃–C₄ level
- Lower third endplate zone: more widely distributed, from approximately C₇ to T₂
Since TrPs are specifically associated with the endplate zone, knowing these locations identifies where TrPs are likely to occur.
The semispinalis capitis overlies the semispinalis cervicis. It is covered above by the upper trapezius and, more laterally, by the splenius capitis.
Primary action: Extension of the head; antigravity control of the head. Importantly, it provides a consistent checkrein function during even slight neck flexion — chronic loading of this checkrein function during sustained forward head posture is the primary mechanism of TrP activation.
Innervation: Branches of the posterior primary division of the first 4 or 5 cervical spinal nerves.
Main synergists (head extension): Deep suboccipital muscles, upper trapezius, splenius capitis, longissimus capitis.
Antagonists: Head flexors, especially the rectus capitis anterior and the anterior fibres of the sternocleidomastoid acting bilaterally.
Referred Pain Patterns
Upper TrP — Enthesopathy Zone (Location 1)
A TrP at Location 1 — the musculotendinous junction region at the base of the skull, approximately 1–2 cm from the midline — produces a pain pattern that travels forward like a band, encircles the head halfway, reaches maximum intensity in the temporal region, and continues on forward over the eye. This is the defining referral pattern of the semispinalis capitis upper TrP.
Tenderness at Location 1 is usually an area of enthesopathy induced by the sustained tension of the taut band fibres of a TrP in the upper third of the muscle (Location 2). The clinician should always check the midbelly portion of the involved muscle fibres for the TrP that is actually causing the patient's pain.
Upper-Third TrP (Location 2)
A TrP at Location 2 — in the upper third of the semispinalis capitis, at or slightly above C₁ — has a pain distribution similar to Location 1: the same band-like temporal and periorbital headache pattern.
INJECTION CAUTION: TrPs at Location 2 should NOT be injected because of proximity to the vertebral artery, which lies deep and below the lower margin of the occipital bone at this level.
Middle-Third TrP (Location 3)
A TrP at Location 3 — in the middle third of the semispinalis capitis, lateral to the region of the C₃–C₄ spinous processes — produces a pain pattern referred over the posterior occiput. Sola identified two lower semispinalis capitis TrP locations that also refer pain to the suboccipital region and, in addition, to the vertex.
The semispinalis cervicis can also refer pain in a pattern similar to that of the middle semispinalis capitis.
Greater Occipital Nerve Entrapment
Entrapment of the greater occipital nerve is commonly caused by tension due to TrPs in the upper portion of the semispinalis capitis and/or the upper trapezius muscles. The greater occipital nerve (the medial branch of the dorsal primary division of the second cervical nerve) emerges below the posterior arch of the atlas, curves around the lower border of the obliquus capitis inferior, and crosses the semispinalis capitis and trapezius muscles near their attachments to the occipital bone.
In an autopsy study of 20 cases (40 nerves) without history of headache, the greater occipital nerve penetrated the semispinalis in 90% of cases. Eleven of 18 nerves that penetrated the trapezius showed evidence of compression — an unexpected finding in subjects without headache history.
Entrapment symptoms (additional to TrP pain): numbness, tingling, and burning pain in the scalp over the homolateral occipital region — so-called "occipital neuralgia." Patients with nerve entrapment:
- Usually prefer cold rather than heat
- Look for an ice-bag to relieve the burning neuropathic pain
- May have received anaesthetic blocks of the greater occipital nerve, with relief only for the duration of the local anaesthetic effect
Entrapment symptoms are often relieved by inactivation of TrPs in the semispinalis capitis and/or upper trapezius, which usually respond well to local procaine injection or dry needling.
Activation and Perpetuating Factors
Acute Trauma
- Falling on the head, experiencing forceful head movement in a motor vehicle accident, or diving head-first — all produce forceful neck flexion and muscle strain even without fracture
- The semispinalis capitis was the third most frequently involved muscle in systematic whiplash studies: present in 73% of frontal impacts, 69% of passenger-side impacts, 63% of driver-side impacts, and 62% of rear impacts
Postural Stress
Chronic strain of the checkrein function is the dominant perpetuating factor:
- Reading, writing, or working at a computer with a forward head posture and the neck in sustained flexion
- The position may be assumed because:
- Eyeglass lenses have too short a focal length
- Eyeglass frames are adjusted improperly so the lower rim contacts the cheek (Fig. 16.4A)
- The chair has inadequate lumbar support
- Work equipment is ergonomically incorrectly positioned (e.g., keyboard)
- TrPs in the pectoralis major muscles produce round-shouldered posture and increase thoracic kyphosis
- The patient is emotionally depressed
- Excessive cervical extension at night: lying supine without a pillow, or with a too-hard or poorly-fitted pillow, places these muscles in a shortened position for a prolonged period. Young people lying prone propped up on elbows to watch television do the same.
- A patient with a long supple neck is more prone to develop active TrPs than one with a short stocky neck, because of the greater leverage and demand placed on the muscles for support
Key Trigger Points
Semispinalis capitis TrPs frequently develop as satellite TrPs in response to key TrPs in either the upper trapezius or splenius capitis muscles. Elimination of key TrPs in either of these two muscles usually inactivates the semispinalis capitis TrPs without direct treatment. Conversely, inactivating only the satellite TrP results in its reactivation and perpetuation by the key TrP.
Other Factors
- Neuropathy: increased nerve irritability from entrapment, as in spinal radiculopathy, can be a significant factor
- Facet joint arthritis: atlantoaxial (C₁–C₂) facet joint osteoarthritis produces a distinctive clinical syndrome with occipital TrPs as one of the major features
- A bathing cap that is too tight or a heavy overcoat with a tight collar that compresses the posterior cervical muscles and impairs blood flow may activate TrPs
Clinical Examination
Range of Motion Assessment
Patients typically show marked restriction of head and neck flexion, which can measure 5 cm short of the chin reaching the sternum. Altered segmental motion of the cervical spine to palpation is a common associated finding.
Marked restriction of head and neck rotation and sidebending usually indicates involvement of associated neck muscles. Restriction in all directions, however, usually indicates a capsular (arthritic) pattern.
Patients often:
- Hold the head and neck upright with the shoulders high
- Position the head with the face tilted up somewhat
- Tend to suppress the bobbing and nodding movements that ordinarily accompany talking
If TrP involvement is mainly unilateral and the head and neck are flexed, the muscles on the painful side may appear very prominent, like a rope from the skull to the level of the shoulder girdle.
Trigger Point Examination
All three posterior cervical locations are best examined by flat palpation with the posterior cervical musculature relaxed — achieved by providing adequate head and body support with the patient seated or sidelying. Slight flexion of the head and neck enhances taut band tension and tenderness, making TrPs more distinguishable.
Location 1 (musculotendinous junction, suboccipital): usually feels indurated and often must be pressed very firmly to elicit referred pain. Found approximately 1–2 cm from the midline at the base of the skull. Tenderness here is usually enthesopathy — always check Location 2 or 3 for the causative mid-muscle TrP.
Location 2 (upper third, at or above C₁): active TrP palpation elicits marked local tenderness and induces the characteristic referred pain pattern. A taut band in the semispinalis capitis may be palpated if the upper trapezius is relaxed, distinguished by its nearly vertical fibre direction.
Location 3 (middle third, lateral to C₃–C₄ spinous processes): flat palpation elicits marked local tenderness and reproduces the occipital referred pain pattern. The muscle lies deep to both the upper trapezius and splenius capitis — relatively deep penetration of palpation is required.
Distinguishing taut bands: The semispinalis capitis fibres run nearly vertically, parallel to the vertebral column. The more diagonal fibres of the splenius capitis and the rotatores help distinguish them. A local twitch response is difficult to elicit by manual palpation of this muscle in many patients.
Differential Diagnosis
| Condition | Distinguishing features |
|---|---|
| Tension-type headache | Semispinalis capitis TrPs are a primary unrecognised source of tension-type headache; the band-like temporal encirclement pattern is characteristic; confirm by reproducing the headache on TrP palpation at Locations 2 or 3 |
| Cervicogenic headache | Bogduk and Simons report overlapping pain patterns of cervical zygapophysial joints and posterior cervical muscles; the C₂–C₃ zygapophysial joints particularly need consideration alongside semispinalis capitis TrPs; both conditions frequently coexist and both must be treated |
| Occipital neuralgia (greater occipital nerve entrapment) | Greater occipital nerve entrapment symptoms (burning, tingling, scalp numbness) often occur as a sequel to semispinalis capitis TrPs; Tinel's sign at the nerve emergence point; neuropathic quality (burning) superimposed on the dull TrP ache; ice preferred over heat; symptoms relieved by TrP inactivation |
| Location 1 suboccipital tenderness is one of the designated fibromyalgia tender point sites; finding a positive occipital tender point should alert the examiner to the possibility of enthesopathy secondary to a semispinalis capitis TrP in the midbelly | |
| Atlantoaxial (C₁–C₂) facet joint osteoarthritis | Distinctive clinical syndrome in elderly women: occipital and postauricular pain, palpable cervical crepitus, limited head rotation, tender points or TrPs confined to the occipital area, abnormal head position; crepitus and taut band recognition are the two most clearly distinguishing characteristics |
| Splenius capitis TrPs | Splenius capitis refers specifically to the vertex (same side); semispinalis capitis refers in a band pattern to the temple and over the eye; splenius capitis TrPs are a key TrP for semispinalis capitis satellites |
| Rheumatoid arthritis / spondyloarthropathy | Subaxial subluxation, enthesopathy with diastrophic calcification, and atlantoaxial involvement must be excluded by imaging before manual treatment; inflammatory markers and imaging distinguish |
Treatment
Trigger Point Release
Treatment of full-range stretching is contraindicated across joints that exhibit primary hypermobility. When TrPs are in muscles that cross hypermobile joints, use TrP pressure release, hold-relax (mild contraction, not maximum), counterstrain, indirect myofascial release, TrP injection, deep stroking, or stripping massage rather than maximum stretch.
Longitudinal posterior cervical muscles (semispinalis capitis and longissimus capitis) — spray and stretch:
- Patient seated in an armchair, hips moved forward slightly to better recline the trunk against the backrest
- Patient lets the head and neck hang forward and relaxed, as the clinician's hand monitors and encourages this movement to take up the slack in the extensors
- Vapocoolant spray applied upward over the back of the neck and head (Fig. 16.6A)
- Patient asked to slump forward further as the operator continues to take up slack (does NOT use force) and applies a downspray pattern bilaterally to cover the long paraspinal muscles from the occiput to the lower thorax (Fig. 16.6B)
- Facilitated by the patient trying to "hump the back" — adds reciprocal inhibition and voluntary stretch
- This can be continued down the lower thoracic and lumbar spine
- Can be combined with postisometric relaxation: patient looks up and gently breathes in (operator lightly resists the contraction of the posterior cervical musculature with one hand), then patient looks down, breathes out, and relaxes completely, letting the head fall forward (Fig. 16.6C)
- Hot pack applied immediately after spray and stretch
CAUTION: Do not apply forceful pressure to the head in the flexed position — this can stress the cervical spine enough to cause complications in medically compromised spines.
Manual release technique (Fig. 16.6C): Patient supine. Clinician cradles the patient's head and, with the other hand, applies pressure along the distal attachments of the muscle, sidebending the patient's head away from the involved longissimus capitis and using small amounts of rotation to take up slack. When the endpoint of stretch is reached, the patient takes an easy shallow breath and then exhales slowly and fully during relaxation to augment the stretch.
Trigger Point Injection
Injection should be considered only after stretch and spray or other noninvasive treatment has been tried and the patient's TrP pain and restricted neck motion persist. Patients with fibromyalgia are relatively intolerant of manual release techniques — injection may be the preferred TrP therapy for them.
Location 1 (musculotendinous junction): The needle is angled upward, directed toward the occipital bone, not below the bony margin. This avoids the vertebral artery, which lies deep and below the lower margin of the occipital bone. Immediate restoration of full neck flexion may follow treatment here. Scalp pain and hyperesthesia from prior occipital nerve entrapment may last from a few days to several weeks after TrP inactivation.
Location 2 (upper third, near C₁): SHOULD NOT BE INJECTED because of proximity to the vertebral artery. Use intermittent cold and stretch, TrP pressure release, and deep massage to inactivate these TrPs.
Location 3 (middle third, near C₃–C₄): The most likely location of TrPs in this muscle. The middle portion lies deep to both the upper trapezius and splenius capitis muscles. Requires relatively deep penetration — injection of TrPs near the C₃–C₄ region usually does not pose a serious threat to the vertebral artery. The needle should not penetrate the area superior to C₂ where the artery is vulnerable. A 5-cm (2-in) needle may be needed.
Injection of the posterior cervical muscles is frequently bilateral. A common mistake is failure to inject deeply enough because of the possibility of penetrating the vertebral artery in the posterior cervical triangle or the dura mater of the spinal cord. In general, penetration into the spinal canal is avoided by always angling the needle slightly laterally when injecting the deeper paraspinal muscles.
Injection is followed immediately by spray and stretch (or another method of gentle muscle release and lengthening) of the injected muscle, then by full active range of motion. A hot pack can be applied to rewarm the skin.
Corrective Actions
Postural (primary):
- A reading stand or adjustable music stand to change the angle of, or to raise, the reading and work materials to approximate eye-level contact and avoid sustained head and neck flexion
- Elevation of the computer monitor when used continuously for prolonged periods or when it requires a downward gaze
- Eyeglasses with adequate focal length so the patient can see clearly with the head in a balanced upright position; otherwise, a new prescription for longer focal length lenses ("card playing or computer glasses") should be obtained
- Selection of bifocal insets that are large, fully half the height of the entire lens, when needed for close work such as reading or sewing
- Adjustment of eyeglass frames so the lower portion of the rim does not occlude the line of sight on looking down
- Exercising on a stationary bicycle sitting upright with the arms swinging freely or placed on the hips, and not hunched over holding low handlebars
- Placing a cloth roll or pillow behind the thoracolumbar junction while sitting, to maintain the normal lumbar lordotic curve and lift the sternum
- Inactivation of pectoralis major or minor TrPs that induce round-shouldered posture and functional thoracic kyphosis
Sleeping posture:
- Excessive cervical extension at night is corrected by obtaining a slightly softer (non-sagging) mattress, or by using a small soft neck pillow that comfortably supports the normal cervical curve (e.g. Cervipillo)
- A jiggly foam rubber pillow must be discarded and replaced with one filled with a non-springy material, such as feathers or shredded dacron
Environmental:
- Keep the neck covered at night (turtle-neck sweater worn in bed, or a loose scarf draped around the neck) to prevent chilling of fatigued muscles
- Protect the neck from cold drafts during the day; long hair offers natural protection
Exercise therapy (combined self-stretch in the shower — Fig. 16.11): This is a primary form of self-therapy combining levator scapulae, upper trapezius, posterior cervical, and suboccipital muscles:
- A: Self-stretch of the right levator scapulae — looking down toward the opposite axilla, grasping the rotated head above the mastoid area, taking up slack, while reaching downward toward the floor with the free hand to lengthen the muscle
- B: Self-stretch of the right upper trapezius — sidebending the neck to the opposite side, rotating the face as far as comfortable to the same side as the involved muscle, slowly exhaling, allowing the weight of the arm to take up slack
- C: Self-stretch of the posterior cervical muscles — the occipital region grasped by the thumbs as the hands assist active head flexion, while the patient looks down and slowly exhales
- Active range of motion should follow each stretch
- NOTE: By slowly sidebending and turning the head, one can explore intermediate positions for any taut bands that need release. The warm shower water assists in relaxation and release. Head-rolling exercises or other movements which hold the head in extreme positions while changing the direction of stretch should be avoided
A lightweight sandbag may be placed on the head during periods of the day for posture training.
A soft collar worn loosely as a chin rest (NOT tightly for immobilisation) may temporarily relieve neck strain after an acute exacerbation, when riding in a car or working at a desk.
Satellite Trigger Points
- Upper trapezius — key TrP for semispinalis capitis; inactivation of upper trapezius often resolves semispinalis capitis satellites
- Splenius capitis — key TrP for semispinalis capitis; inactivation resolves satellites
- Semispinalis cervicis — deep to semispinalis capitis; frequently co-active; similar pain pattern in the middle region
- Longissimus capitis — same functional layer; ear/postauricular referral when involved
- Levator scapulae — released together in the combined shower self-stretch
- Suboccipital muscles — treat suboccipital group first before releasing the longer posterior cervical muscles
Related Pages
- Pain:Temporal Headache — Band-like semispinalis capitis referral pattern
- Pain:Occipital — Middle and lower semispinalis capitis TrP referral
- Pain:Head and Neck — Diagnostic algorithm
- Muscle:Semispinalis Cervicis — Deep companion muscle; similar mid-region pain pattern
- Muscle:Longissimus Capitis — Same functional layer
- Muscle:Splenius Capitis — Key TrP; superficial to semispinalis capitis
- Muscle:Trapezius/Upper — Key TrP; covers semispinalis capitis
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 16.