Muscle:Trapezius

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Trapezius

The trapezius is a large, tripartite, superficial muscle of the neck and back. It is probably the muscle most commonly beset by myofascial trigger points of any muscle in the body. Because its three portions — upper, middle, and lower — have different fibre directions, different functions, and different trigger point patterns, they are treated here as functionally distinct divisions. A seventh trigger point (TrP7) is probably a skin trigger point producing a referred autonomic response rather than a myofascial TrP in the classical sense.

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Upper Trapezius

Anatomy

The upper (superior) fibres arise from the medial third of the superior nuchal line and, in the midline, from the ligamentum nuchae. They converge laterally and forward to attach to the posterior border of the lateral third of the clavicle. The fibres run nearly horizontal (at an elevation of less than 20°) and are therefore oriented to draw the lateral end of the clavicle medially and upward by rotating it around the sternoclavicular joint. This rotation of the clavicle at the sternoclavicular joint raises the clavicle and, indirectly through the acromioclavicular joint, the scapula. The upper fibres are shaped, together with the contralateral side, like a coat hanger.

Innervation: Motor innervation is supplied by the spinal portion of the accessory nerve (cranial nerve XI), arising from ventral roots of the first five cervical segments. Sensory fibres from C₂, C₃, and C₄ join the plexus to supply both motor and sensory innervation to the muscle.

Function: Acting unilaterally, the upper trapezius extends and laterally flexes the head and neck toward the same side, and in extreme rotation turns the face to the opposite side. It draws the clavicle backwards and raises it by rotating it at the sternoclavicular joint, thereby elevating the scapula indirectly. Acting bilaterally, the upper fibres extend the head and neck against resistance. The upper trapezius provides the upper component of the force couple necessary to rotate the glenoid fossa upward, working with the lower serratus anterior and the levator scapulae.

Referred Pain

TrP₁ (central TrP, most vertical fibres): Located in the midportion of the anterior border of the upper trapezius, at the most vertical fibres attaching to the clavicle. This is the most frequently identified myofascial TrP location in the entire body.

Refers pain unilaterally upward along the posterolateral aspect of the neck to the mastoid process. When intense, the pain extends to the side of the head, centring in the temple and the back of the orbit, and may include the angle of the jaw. It is a major source of tension-type neckache. Pain may occasionally appear in the pinna of the ear, but not deep inside it. Stimulation of this TrP by needling or injection has initiated referred vasomotor effects in the homolateral and contralateral ear.

TrP₂ (central TrP, more horizontal fibres): Located in the middle of the more nearly horizontal fibres of the upper trapezius, slightly caudal and lateral to TrP₁. Refers pain slightly posterior to the essential cervical zone of TrP₁, blending with its distribution behind the ear. Causes similar neck pain but usually without headache. Pain from TrP₂ occurs on motion only when the head and neck are almost fully rotated actively to the opposite side (which contracts the muscle in a shortened position).

TrP locations and referred pain — Upper Trapezius
TrP Type Location Essential referred zone Spillover / notes
TrP₁ Central Midportion anterior border, most vertical fibres Posterolateral neck → mastoid → temple → back of orbit May include angle of jaw, pinna of ear (not deep); vasomotor ear effects; overlap with SCM, suboccipital, temporalis → tension headache
TrP₂ Central Middle of more horizontal upper fibres, caudal/lateral to TrP₁ Posterolateral neck, slightly posterior, behind ear Usually without headache; pain only at end-range active rotation to opposite side

Satellite TrPs

TrP₁ and TrP₂ in the upper trapezius commonly activate satellite TrPs in the temporalis, masseter, splenius, semispinalis, levator scapulae, and rhomboid muscles. Pain referred down the arm in response to stimulation of trapezius TrP₁ is usually referred from satellite scalene muscle TrPs. The lower trapezius TrP₃ is a key TrP that frequently induces satellites in upper back and neck muscles, including TrP₁ and TrP₂ in the upper trapezius.

Autonomic phenomena

Occasional reports associate TrP activity in the upper trapezius fibres with symptoms of dizziness or "vertigo," including momentary dizziness when the TrP is penetrated by a needle during injection. This postural dizziness may be referred directly from the trapezius or may result from reflex stimulation of active TrPs in the clavicular division of the synergistically related sternocleidomastoid muscle.

Symptoms and Patient Presentation

The patient usually has severe posterolateral neck pain that is often constant and associated with temporal headache on the same side. The patient may be misdiagnosed as having cervical radiculopathy or atypical facial neuralgia. With very active upper trapezius TrPs and additional involvement of the levator scapulae or splenius cervicis muscles, the patient may develop an acute "stiff neck," painfully limiting rotation of the head toward the same side (which elongates the upper trapezius).

TrP₁ and TrP₂ activity may cause intolerance to the weight of heavy clothing (e.g., a misfitting heavy overcoat) resting on the angle and back of the neck and on the acromion processes.

The patient tends to fold the arms across the chest and cradle the chin in one hand, and may be seen to rub the trapezius muscle and to keep moving the head as if trying to stretch the muscle. An apparently elevated shoulder is often visible on the side of the thickened, tense upper trapezius, with a slight tilt of the neck toward the more affected side.

Examination Findings

Range of motion: When the trapezius alone is involved, there is minimal limitation of head and neck rotation. The most restricted movement is lateral flexion (sidebending) of the head and neck away from the involved upper trapezius, which may be reduced to 45° or less. When sidebending is tested and the head is then rotated toward the side of the involved muscle, the patient may feel increased tension and/or referred pain along the side of the neck. Active rotation of the head to the opposite side is usually painful at the extreme range of motion (the muscle contracts strongly in its most shortened position). Active rotation to the same side is usually pain-free, unless either the levator scapulae on the same side or the opposite upper trapezius also harbours TrPs. Neck flexion is only slightly restricted, as is arm abduction due to the painfully restricted upward rotation of the scapula.

Postural observation: The upper trapezius is characteristically prone to hyperactivity and increased tension, while the lower trapezius tends toward inhibition and weakness.

Trigger Point Examination

With the patient supine, or possibly seated, place the muscle on moderate slack by bringing the ear slightly toward the shoulder on the same side. Using a pincer grasp, lift the entire free margin of the upper trapezius off the underlying supraspinatus muscle and the apex of the lung. Roll the muscle firmly between the fingers and thumb to palpate for a nodule and firm taut band to locate the spot tenderness of TrP₁. Sustained compression of the TrP often evokes pain referred to the neck, occiput, and temple.

Pain caused by loading the muscle (abducting the arm above 90°) is prevented by firm pressure on the muscle with the palm of the hand during abduction.

Four criteria are highly reliable in this muscle after a brief period of training: detection of spot tenderness, palpation of a taut band, the presence of referred pain, and reproduction of the subject's symptomatic pain. Identification of a local twitch response (LTR) by manual palpation was unreliable in this muscle, but when present, an LTR is a strong confirmatory finding and is especially valuable when needling TrPs therapeutically.

Middle Trapezius

Anatomy

The middle fibres attach medially to the spinous processes and interspinous ligaments of C₆ through T₃ vertebrae and laterally to the medial margin and superior lip of the spine of the scapula. The fibres run nearly horizontally. The more superior middle fibres attach to the acromion and assist in adducting the scapula; they can also serve as part of the force couple that upwardly rotates the scapula. The more inferior fibres that attach to the spine of the scapula are more horizontal and effectively adduct the scapula (move it toward the midline).

Function: The middle trapezius acts synergistically with the rhomboid muscles to adduct the scapula. By fixing (stabilising) the scapula, the middle fibres are also synergistic with the deltoid, supraspinatus, and long head of the biceps brachii in elevation of the arm at the shoulder joint. These trapezius fibres are antagonists to all but the most caudally directed fibres of the pectoralis major muscle. The middle and lower trapezius fibres serve primarily to stabilise the position of the scapula while other muscles rotate it. Because of its dual function, the middle trapezius cannot be unambiguously assigned to either hyperactive or inhibited category.

Referred Pain

TrP₅ (central TrP): Located by flat palpation midfibre in the nearly horizontal fibres, approximately 1 cm medial to the scapular attachment of the levator scapulae. Refers superficial burning pain medially, concentrated between the TrP and the spinous processes of C₇ to T₃.

TrP₆ (attachment TrP): Found near the acromion at the lateral musculotendinous junction of the middle trapezius fibres. Tenderness in this region is likely enthesopathy at the end of the taut bands associated with a central TrP₅. Refers aching pain to the top of the shoulder or acromion. Most likely caused by enthesopathy secondary to a central TrP₅ of the middle trapezius near the region of the oval area.

TrP locations and referred pain — Middle Trapezius
TrP Type Location Essential referred zone Notes
TrP₅ Central Midfibre, ~1 cm medial to levator scapulae scapular attachment Interscapular, between TrP and C₇–T₃ spinous processes Superficial burning quality; pectoral muscles commonly need releasing first
TrP₆ Attachment Lateral musculotendinous junction near acromion Top of shoulder / acromion Likely enthesopathy secondary to TrP₅; relief requires inactivating TrP₅ first

Symptoms and Patient Presentation

TrP₅ causes the patient to complain of burning interscapular pain. TrP₆, which probably represents an attachment TrP, produces more localised pain and tenderness over the acromion, making the shoulder intolerant of pressure from a well-fitted heavy coat, or from a ponderous purse carried on a shoulder strap.

The patient with pain arising from the middle trapezius is likely to have a round-shouldered posture, secondary to shortening of the antagonistic pectoralis major and/or minor muscles due to their active or latent TrPs. The strong pectoral muscles exhaust the weaker middle trapezius fibres in their futile effort to adduct the scapulae and maintain a normal posture. These middle trapezius fibres are subject to strain when the driver of a car holds the hands on top of the steering wheel, in a round-shouldered position.

Examination Findings

Postural observation: Round-shouldered posture secondary to shortened antagonistic pectoralis muscles. Check for pectoral muscle tightness as it is almost always the primary driver of middle trapezius overload.

Trigger Point Examination

For examination of middle and lower trapezius TrPs, the patient sits with the arms folded across the front of the body to abduct the scapulae and "humps the back" to flex the dorsal spine. Cross-fibre palpation identifies taut bands by rolling them against the underlying ribs. The firm bands usually exhibit visible local twitch responses to snapping palpation of the TrP.

TrP₅ is located by flat palpation midfibre (right side of Fig. 6.3) in the nearly horizontal fibres, approximately 1 cm medial to the scapular attachment of the levator scapulae.

The middle trapezius responds well to TrP pressure release by the operator or self-release by the patient using a cold tennis ball. It also responds well to local massage of the taut band in the region of the TrP.

Lower Trapezius

Anatomy

Fibres from this fan-shaped part of the muscle attach medially to the spinous processes and interspinous ligaments of approximately T₄ through T₁₂ and laterally to the region of the tubercle at the medial end of the spine of the scapula, just lateral to the lower attachment of the levator scapulae muscle.

Function: The lower fibres adduct the scapula and are said by most authors to depress the scapula and to rotate the glenoid fossa upward. However, a careful biomechanical analysis suggests these lower fibres are in no position to contribute net torque about the axis to help rotate the glenoid fossa upward. Rather, the middle and lower trapezius fibres serve primarily to stabilise the position of the scapula while other muscles (primarily serratus anterior, complemented by the upper trapezius) rotate it. In stabilising the axis of rotation of the scapula, the lower fibres are synergistic with the lower part of the serratus anterior and with the upper fibres of the trapezius in upward rotation of the glenoid fossa of the scapula.

Referred Pain

TrP₃ (central TrP — the "joker" TrP): Located in the midfibre region of the lower trapezius usually near the lower border of the muscle, close to where the lowest fibres cross the medial border of the scapula (at or below the level of the inferior angle of the scapula). This TrP is very common, very important, and frequently overlooked.

Refers pain severely to the high cervical region of the paraspinal muscles, to the adjacent mastoid area, to the acromion, and refers an annoying deep ache and diffuse tenderness over the suprascapular region. The patient tends to rub the tender region. Such referred diffuse tenderness should not be mistaken for the focal tenderness of a TrP.

TrP₃ is often the "joker" responsible for persistent upper back and neck pain after the active TrPs in the upper trapezius and other shoulder and neck muscles have been eliminated. TrP₃ is a key TrP that commonly induces satellite TrPs in upper back and neck muscles. Satellite TrPs may appear in TrP₁ and TrP₂ of the upper trapezius, and sometimes in the levator scapulae and posterior cervical muscles.

TrP₄ (attachment TrP): Found in the region of the lateral musculotendinous junction of the lower trapezius near where it attaches to the deltoid tubercle on the root of the spine of the scapula. Refers a steady burning pain downward along and medial to the vertebral border of the scapula. Most likely a region of enthesopathy secondary to central TrP₃; should recover following inactivation of the TrP₃ that is causing it.

TrP locations and referred pain — Lower Trapezius
TrP Type Location Essential referred zone Notes
TrP₃ Central ("joker") Midfibre, near lower muscle border, where lowest fibres cross medial scapular border High cervical paraspinals, mastoid area, acromion, suprascapular region (deep ache + diffuse tenderness) Very commonly overlooked; key TrP driving satellite TrPs in upper trapezius and neck; often responsible for persistent neck pain after upper TrPs treated
TrP₄ Attachment Lateral musculotendinous junction, deltoid tubercle at root of spine of scapula Burning pain, downward along/medial to vertebral scapular border Likely enthesopathy secondary to TrP₃; should resolve when TrP₃ is inactivated

Symptoms and Patient Presentation

TrP₃ and TrP₄ cause suprascapular, interscapular, acromial, and/or neck pain with little, if any, restriction of neck motion. TrP₃ is often the "joker" responsible for persistent upper back and neck pain after the active TrPs in the upper trapezius and other shoulder and neck muscles have been eliminated.

Active TrPs in the lower fibres may affect upward rotation of the scapula because of impairment of their stabilisation function. If the lower trapezius is inhibited and weak from the activity of TrPs, the scapula may be elevated and the upper part tilted forward (coracoid process tilted forward and downward), and the patient will exhibit a round-shouldered posture.

Lower trapezius weakness, which can occur from inhibition by its own TrPs or from other sources, may allow the scapula to ride up and tilt downward anteriorly (forward and downward tilt of coracoid process), and may lead to adaptive shortening of the pectoralis minor muscle. The resultant position of the scapula and "round-shouldered" posture can be seen by the examiner.

Activation and Perpetuation

The lower fibres are strained during prolonged bending and reaching forward while sitting (e.g., to reach the desk when the knees lack space under its surface) and by supporting the chin on the hand while resting the elbow on the front of the chest because armrests are missing.

The lower part of the trapezius is often the key to successful treatment of the upper trapezius, levator scapulae and some neck extensor muscles; these muscles lie in the pain reference zone of the lower trapezius and may develop satellite TrPs to the key lower trapezius TrP.

Examination Findings

Lower trapezius weakness and TrPs may allow the scapula to ride up and tilt downward anteriorly, producing a round-shouldered posture visible to the examiner.

Trigger Point Examination

For examination, the patient sits with the arm forward and the scapula abducted to put the lower fibres on moderate stretch. The patient also "humps the back" to flex the dorsal spine. The TrP₃ central TrP usually lies in the lateral margin (the most inferior fibres) close to where the lower border of the muscle crosses the medial border of the scapula, or sometimes at or below the level of the inferior angle of the scapula. This TrP₃ sometimes feels like a button or nodule within the taut band and is easily missed if slack in the muscle has not been eliminated.

TrP₄ is found in the region of the lateral musculotendinous junction of the lower trapezius near where it attaches to the deltoid tubercle on the root of the spine of the scapula.

Sidelying on the uninvolved side is usually the preferred position for examining TrPs in the lower trapezius and the middle trapezius.

Activation and Perpetuation of Trigger Points

Upper Trapezius

TrPs may be activated by sudden trauma such as falling off a horse, falling down steps, suffering a cervical flexion-extension injury ("whiplash") in an auto accident. The upper trapezius TrPs may be activated by, and remain as sequelae to, cervical radiculopathy.

Its function of neck stabilisation is commonly overloaded by tilting of the shoulder-girdle axis due to a lower limb-length inequality or small hemipelvis (body asymmetry). The limb asymmetry tilts the pelvis, which bows the spine into a functional scoliotic curve and, in turn, tilts the shoulders, causing one to sag.

The normally minimal antigravity function of the upper trapezius is overstressed by any position or activity in which the trapezius helps carry the weight of the arm for a prolonged period:

  • Telephoning or sitting without armrest support, particularly when the upper arms are congenitally short
  • Holding the arms elevated to reach a high keyboard or a high drawing board
  • Working with sewing material on the lap with the elbows unsupported
  • Sustained elevation of the shoulders as an expression of anxiety or other emotional distress; playing the violin
  • Rotation of the head far to one side in a fixed position (holding the head turned to converse with a person seated at the side, or sleeping prone with the head strongly rotated)
  • Pressure from tight narrow bra straps supporting large breasts, the shoulder strap of a ponderous purse, a heavy backpack, or a heavy coat

Armrests that are too high push the scapulae up and shorten the upper trapezius for long periods.

Middle Trapezius

This part of the muscle also becomes overloaded when the arm is held up and forward for a long time. Sustaining this position also overloads the pectoralis major fibres, which are prone to develop latent (painless) TrP activity that increases their tension, pulling the arm and scapula forward. Then, the antagonistic middle trapezius fibres become overstretched and weakened by this unrelenting abduction of the scapula and protraction of the shoulder. The middle trapezius (and rhomboid) muscle fibres may be overloaded and may then develop active TrPs that cause pain.

Lower Trapezius

The lower fibres are strained during prolonged bending and reaching forward while sitting (to reach the desk when the knees lack space under its surface) and by supporting the chin on the hand while resting the elbow on the front of the chest because armrests are missing.

Differential Diagnosis

Misdiagnosis of trapezius TrP pain

Pain arising from trapezius TrPs commonly leads to a mistaken diagnosis when a TrP origin of the pain is not investigated. The most common misdiagnoses include:

  • Tension headache — referred pain to the head from TrPs in several masticatory and neck muscles (including the upper trapezius) at the same time is easily and frequently mistakenly diagnosed as tension headache. Pain originating from TrPs in the upper trapezius and the splenius capitis muscles can confusingly simulate occipital neuralgia and cervicogenic headache.
  • Cervical radiculopathy — upper trapezius TrP pain may be mistaken for this.
  • Atypical facial neuralgia — referral to the temple, jaw, and orbit from TrP₁.
  • Bursitis — shoulder pain from the lower trapezius TrP may be mistaken for bursitis.
  • Chronic intractable benign pain of the neck and/or back — myofascial pain from any part of the trapezius muscle (often in combination with other muscles) can lead to this diagnosis, which according to the authors is nearly always of myofascial origin and therefore does not stand up as a valid diagnosis.
  • Fibromyalgia — patients with chronic axial pain that includes multiple regional involvement should be examined for tender points diagnostic of fibromyalgia; however, trapezius TrPs are a common finding.

Distinguishing trapezius TrP pain from other muscles

When patients have both neck pain and shoulder pain, levator scapulae and infraspinatus TrPs were more frequently the cause than were trapezius TrPs. When patients have pain and deep tenderness referred to the suprascapular region, but do not have active trapezius TrPs, the responsible TrPs are likely to be found in the levator scapulae or scalene muscles.

Differential: which muscle is responsible?
Pain pattern More likely if trapezius More likely if another muscle
Posterolateral neck + temporal headache TrP₁ (upper trap): pain constant, severe, unilateral; associated with TrP in taut band palpable in anterior border of upper trap SCM (sternal head): similar temporal/vertex pattern but also autonomic features (lacrimation, rhinorrhoea, red eye). Splenius capitis: pain to vertex/eye but pain on rotation to same side (not opposite)
Occipital / mastoid area pain Lower trapezius TrP₃ refers to mastoid and high cervical paraspinals Semispinalis capitis: deep aching at occiput. SCM (clavicular head): diffuse headache. Suboccipitals: pain behind the eye and occiput
Interscapular burning pain Middle trap TrP₅: superficial burning between TrP and C₇–T₃ spinous processes Rhomboids: deep, nagging ache along medial scapular border. Infraspinatus: pain referred anteriorly to front of shoulder. Serratus posterior superior: deep ache in interscapular region
Suprascapular deep ache + diffuse tenderness Lower trap TrP₃ (often overlooked; check this before assuming the upper trap is the sole culprit) Levator scapulae: suprascapular ache with restricted rotation to opposite side and stiff neck. Scalenes: may refer to suprascapular area
Shoulder / acromion pain Middle trap TrP₆ (attachment TrP near acromion) or lower trap TrP₄ Supraspinatus: pain over deltoid area + arm weakness with abduction. Infraspinatus: anterior shoulder + arm referral. Bursitis (usually has arc sign and capsular end-feel)

The symptoms caused by upper trapezius TrPs may be closely associated with and confusingly similar to somatic or articular dysfunctions below the C₂, C₃, and C₄ vertebrae. Commonly, one or more of these restricting articular dysfunctions and upper trapezius TrPs coexist, and both must be treated. An upper trapezius source of pain may be differentiated from a joint source by testing for pain on sidebending of the cervical spine, then:

  1. Passively support the patient's upper limb and sidebend the cervical spine again. If the pain is markedly reduced or absent, the problem may be in the trapezius.
  2. Apply pressure downward on the shoulder (as in lengthening the upper trapezius). If there is an increase in pain, the upper trapezius may be the source of the problem.
  3. If neither of these tests changes the pain, the cervical joints (perhaps C₄) may be the problem.

Hypermobility of the C₄ segment has been observed clinically to be associated with the trapezii. Joint stress that causes radiating pain can involve the trapezius secondarily, and the muscle often becomes hyperirritable and develops TrPs.

Related articular dysfunctions are found in the cervical or the thoracic spine depending on which part of the trapezius muscle harbours the TrPs:

  • Upper trapezius TrPs → cervical spine dysfunctions (C₂–C₄)
  • Middle trapezius TrPs → cervicothoracic junction (C₆, C₇, T₁); occasionally T₂. Commonly associated with adduction of the scapulae and elevation of the first rib on the same side.
  • Lower trapezius TrPs → interscapular pain articular dysfunctions may extend from T₄ to T₁₂; usually a central painful segment near T₆ or T₇

Key points for ruling out non-muscular causes

  • Patients with head and neck pain may have a temporomandibular disorder with or without TrPs of masticatory muscles. Related TrPs in other muscles, articular dysfunctions of the cervical spine, and/or any of the diagnoses listed below should be considered.
  • TrPs in the upper trapezius can restrict arm abduction at its full range by the effect on upward rotation of the scapula — this may be confused with subacromial pathology.
  • Beware of satellite TrPs: in the presence of upper trapezius TrPs, associated TrPs are likely to develop in the functionally related levator scapulae and contralateral trapezius muscles, and also in the ipsilateral supraspinatus and rhomboid muscles. Satellite TrPs may appear in the temporalis and occipitalis muscles, which lie within the zones of pain referred from TrPs in the upper trapezius.
  • The lower trapezius TrPs are prone to act as key TrPs and to induce satellite TrPs in the upper trapezius and sometimes in the levator scapulae and posterior cervical muscles. For this reason, always check the lower trapezius for TrPs, especially when the upper trapezius TrPs respond poorly to treatment.
  • A TrP in the lower trapezius may itself be a satellite of a key TrP in the latissimus dorsi muscle.

Entrapment

In one autopsy study of 40 greater occipital nerves, the nerve emerged from just below the occiput through the trapezius muscle in 45% of cases and through the underlying semispinalis capitis muscle in 90% of cases. The nerve can be entrapped as it emerges through the semispinalis capitis when that muscle becomes taut due to more caudal TrPs at the mid-cervical level. The trapezius itself has not been found to entrap the nerve, but may contribute a shearing stress.

When the (spinal) accessory nerve emerges through the sternocleidomastoid muscle, the trapezius muscle may be weakened by entrapment of its motor nerve fibres between taut bands of sternocleidomastoid fibres.

Treatment

Trigger Point Release

Correction of poor posture (particularly "round-shouldered" posture with an excessive forward-head position) and maintenance of good posture are primary in any treatment approach. The upper trapezius is generally recognised as prone to hyperactivity and increased tension, whereas the lower trapezius tends to be just the opposite — inhibited, weak, and overstretched. Therapy that depends primarily on stretch can be counterproductive in muscles prone to inhibition and weakness. For both the middle and lower parts of the trapezius, the application of massage to the taut band, TrP pressure release, and indirect techniques are emphasised, carefully avoiding forceful and excessive stretch. Vapocoolant or icing can precede any of these applications.

Upper trapezius (TrP₁ and TrP₂): The spray-and-release technique is performed with the patient seated in an armchair, leaning back comfortably and fully relaxed, with the arm on the involved side supported on a pillow. The operator guides the patient's head to laterally tilt toward the contralateral side with the head slightly flexed and the face turned slightly toward the involved right side. Vapocoolant spray is applied in parallel sweeps from the acromion to the mastoid area, behind the ear, around to the temple, and sometimes to the jaw (particularly if that area is included in the patient's pattern of referred pain). The operator takes up slack with the guiding hand as it develops in the muscle. Postisometric relaxation for the upper trapezius is an effective addition. The patient should have good elbow support during the procedure and moist heat following release. Spray and stretch should also always be applied to the contralateral trapezius to prevent activation of any TrPs in it due to unaccustomed shortening when the involved muscle is stretched to its maximum normal length.

Middle trapezius: The spray-and-release technique begins with the patient sidelying or semiprone with the involved side uppermost. The right upper limb is elevated 90° (in line with the muscle fibres being released) and dropped forward off the edge of the treatment table to take up slack in the muscle by abducting the scapula. Augmented postisometric relaxation is accomplished by asking the patient to look up, breathe in, then look down, breathe out slowly, relax and let the arm drop toward the floor. This can be repeated two or three times to fully release the muscle fibres. Check both pectoral muscles for tightness (and TrPs) first — most commonly, the middle trapezius stretch-weakness and TrPs are from overload and are secondary; unless the tightness of the anterior muscles causing the problem is effectively addressed, the patient will continue to have trouble.

Lower trapezius: Since the lower trapezius is often weak, the aim is not primarily stretch but release of tension in the taut band. For spray (or icing) and release, the patient lies on the uninvolved side (semiprone) near the edge of the treatment table, elevates the right upper limb approximately 135° (in line with the muscle fibres being released), and lowers the arm over the edge of the treatment table to slightly abduct the scapula and take up slack in the involved muscle. The operator applies the spray from the region of the T₁₂ vertebral attachment of the trapezius, following the muscle fibre direction and fanning laterally and upward to cover its pain reference zone from the acromion to the occiput. Since gravity can assist release of the lower trapezius, it is not necessary for the operator to apply pressure against the patient's scapula; however, the operator's touch can guide and encourage appropriate contraction and relaxation. It is usually best also to treat the contralateral trapezius, which must balance the released tension of the treated muscle.

When the pectoral muscles are involved, their full normal rest length must be restored before the lower trapezius can be relieved of overload, and then the lower trapezius may need to be strengthened.

Trigger Point Injection

The fibres of any part of the trapezius should be injected for TrPs only if spot tenderness is observed in a palpable nodule or taut band and the patient's pain is reproduced by digital compression of the tender spot. Eliciting an LTR by snapping palpation helps to confirm the diagnosis but is too unreliable to be included as a necessary finding. Injection is always followed at once by slow active full range of motion.

TrP₁ (and rarely TrP₂) of the upper trapezius are injected from an anterior approach with the patient supine, using 0.5% procaine solution. For injection of the more anterior central TrP₁, the patient lies supine with the shoulder on a pillow to slacken that part of the muscle. The muscle is held firmly in a pincer grasp to precisely locate the TrPs for injection and to lift the muscle off underlying structures. The needle tip is directed upward across the muscle mass that is held between the digits to avoid any possibility of penetrating the apex of the lung.

Other trapezius TrPs are injected with the patient lying on the uninvolved side with the back toward the operator, or lying prone.

Trapezius TrPs usually respond well to local injection if tight pectoral muscles have been released.

Corrective Actions

Body structure: A lower limb-length inequality or a small hemipelvis must be corrected. When the patient's upper arms are short in relation to torso height, they do not reach the armrests of most chairs; compensating lifts or pads should be provided to raise the effective armrest height.

Postural and activity modifications:

  • No patient with TrPs in the upper trapezius should sleep on a foam rubber pillow; its springiness aggravates TrP symptoms. A non-springy comfortable pillow should be used. Avoid sleeping prone.
  • Chairs should have armrests at the correct height to provide elbow support. Dentists, secretaries, draftsmen, writers, and seamstresses should arrange their seating to provide suitable elbow support.
  • Excessive sustained EMG activity of the upper trapezius is eliminated by lowering the keyboard. If the keyboard height is properly adjusted but the individual leans forward away from the backrest, the upper trapezius muscles may still be overloaded. Lean back against the backrest of the chair so that it supports the scapulae and allow the shoulders to drop down.
  • Muscles are more tolerant of prolonged activity if they have frequent short breaks permitting relaxation. A few cycles of active range of motion makes the break more effective.
  • Standing or walking with hands in the pockets relieves upper trapezius muscle strain.
  • For patients who have long conversations on the telephone, a speaker phone relieves the neck and arm muscles from the strain of holding a handset.
  • Objectionable pressure on the trapezius by a thin, tight bra strap should be relieved by wearing a wider, nonelastic bra strap, and/or by slipping a soft plastic shield under the strap to distribute the pressure. A shoulder-strap purse should be slung over the opposite acromion (not resting on the trapezius muscle).
  • A heavy coat that rests on the upper trapezius, rather than on the acromion to the side, should be avoided; shoulder pads inserted in the coat can properly redistribute its weight.

Tension release exercises: Two exercises are helpful to maintain full length and normal tension of the upper trapezius: the self-stretch technique for the upper trapezius, and postisometric relaxation in the seated position. Two of the safest general conditioning exercises to help shoulder-girdle muscles that include the trapezius are swimming and jumping rope while progressing forward. Jogging tends to aggravate trapezius TrPs.

Middle-trapezius Exercise (for maintaining full active range of motion in the middle and lower trapezius muscles): The patient lies supine on the floor. Place the elbows, forearms, and palms of the hands together in front of the abdomen. Keep the elbows tightly together as long as possible while raising the forearms over the face, then drop the forearms past the face toward the floor, then keeping the back of the elbows and wrists in contact with the floor, swing the arms down against the sides of the body. Pause and relax, taking several slow deep breaths. Repeat the cycle.

Lower trapezius self-stretch: Sit in a chair and reach across in front of the body to the contralateral toes.

See also

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