Ultrasound-Guided Dry Needling: Precision Treatment for Myofascial Pain and Trigger Points

Trigger points are small but they can generate a lot of trouble. A taut band in the upper trapezius, no bigger than a grape, can produce headaches, shoulder restriction, and referred pain down the arm that mimics a rotator cuff tear. Identifying that band accurately, and reaching it safely with a needle, is harder than it sounds – and the difference between accurate and approximate matters considerably when the target sits near the brachial plexus or the apex of the lung.

This article explains the science behind trigger points, what ultrasound guidance actually adds to dry needling, and how NYDNRehab integrates these tools into a broader treatment approach.

The most important theory on trigger points is the integrated model of David Simons and later Gerwin (2023). The core of that model is a faulty motor endplate that secretes excess acetylcholine. Too much acetylcholine causes the sarcomeres to stay contracted and a small group of muscle fibres is unable to relax – the compression of the capillary bed at the same time reduces the delivery of oxygen exactly when it’s needed. The muscle is unable to repolarize completely.

The reason why trigger points are self perpetuating is because of calcium dysregulation. Following a normal contraction, the calcium pump in the sarcoplasmic reticulum removes calcium from the cytoplasm, using ATP. In an ischemic zone (contracted zone), ATP is depleted, and the pump stops. Calcium stays elevated. The sarcomere remains contracted. In this condition, a patient may complain of a constant aching pain at the base of the skull, and may not be able to rotate the neck at all, even on days when they haven’t done anything rigorous – the low level, always present tension is the self sustaining cycle made real.

Pressure sensitivity is the sensation the patient reports, which is stiffness or achiness at rest, and often referred pain that is not dermatomal in distribution. The non-dermatomal referral is the reason that trigger points are misdiagnosed as radiculopathy or nerve entrapment with some frequency. Reviewing the most prominent theories, Zhai et al. (2024) found that none of the integrated hypothesis, central sensitization model, or energy crisis variants are able to account for all the phenomena observed. The clinical implication is that trigger points are likely to be a combination of peripheral and central mechanisms and not a purely local tissue problem.

The treatment of a trigger point without the understanding of the cause is similar to fixing a tire without removing the nail. Trigger points are most likely to recur due to:

The thoracic spine is stiff and the cervical paraspinal muscles and suboccipital muscles must compensate during rotation, which is called altered joint mechanics. Those muscles do not develop trigger points due to weakness, but rather due to overloading caused by a lack of mobility elsewhere.

Fascial restriction: when fascia is dense or adherent, glide is restricted and mechanical stress is focussed at particular points within a muscle. A trigger point is where the load is greatest.

Scapular dyskinesis: if the serratus anterior and lower trapezius do not stabilize the scapula during shoulder elevation, then the upper trapezius and levator scapulae will do so. One of the most common trigger point generators encountered in clinical practice is chronic overuse of those muscles.

Gait dysfunction: tibialis posterior weakness, hip abductor inhibition or leg-length discrepancies alter the distribution of load through the lower kinetic chain. Piriformis, gluteus medius and hamstring trigger points often can be traced to gait asymmetry and not local injury.

Central sensitization reduces the threshold for a motor endplate to become dysfunctional (psychosocial load and disruption of sleep). Patients who are poorly managed with stress or sleep deprivation can develop trigger points more quickly and more easily, and are less likely to resolve the trigger.

Any treatment plan that doesn’t address these upstream drivers will bring temporary relief and frustration to the patient and the clinician.

Palpation-based dry needling is a standard technique that requires the clinician to find a taut band, estimate depth based on surface anatomy, and insert the needle without real-time knowledge of the needle’s trajectory. This is fairly satisfactory in superficial, clearly defined muscles where there are no important structures in close proximity. It is less effective in other locations.

Dynamic (not static pre-procedure) musculoskeletal ultrasound demonstrates:

• Muscle architecture and texture: hypoechoic (darker) areas in the muscle belly are frequently associated with muscle fibre disorganisation, local oedema or fibrosis. The normal, healthy muscle is evenly pennated and displays good echogenicity. A muscle that has been overloaded or injured in the past does not.
• Assessment of fascial thickening and fascial glide: the deep cervical fascia, thoracolumbar fascia and plantar fascia can all be assessed for fascial thickening and the ability to glide against adjacent layers during movement. Dynamic ultrasound shows restricted fascial glide (one layer is not moving, and the other is moving), and is often correlated with the patient’s reported area of stiffness.
• Vascularity: Power Doppler imaging shows increased vascularity in acutely inflamed tendons and entheses. Needling into an area of high Doppler signal is a treatment target and caution flag, as it is more likely to encounter a bleeding complication.
• Nerve location: the brachial plexus, the radial nerve at the spiral groove, the common peroneal nerve at the fibular head, the pudendal nerve in the perineum – all are easily seen on ultrasound. When a needle is advanced in a region where a nerve is known to lie, what is possible is different from what would be possible if the needle were advanced in a region where a nerve was not known to lie.
• Dynamic movement abnormalities: ultrasound during active shoulder elevation may show impingement that is not seen on a static MRI. When the patient raises their arm, the supraspinatus tendon moves beneath the acromion, so what you are seeing and the location of what you are seeing changes.

“Palpation-based” is not synonymous with the lack of skill. Traditional landmarks are competent in appropriate anatomical territories by experienced clinicians. The comparison is not between the level of training of the practitioner, but rather between what each approach can and cannot confirm.

Some areas are sufficiently close to vulnerable structures where the margin for error is large and meaningful when imaging in real time is not used.

• Cervical paraspinals and scalenes: the top of the lung is at a higher level than most patients (and some clinicians) think. Common trigger point generators in patients with neck pain and thoracic outlet symptoms, the scalene muscles are adjacent to the subclavian artery and brachial plexus. In the literature there are reports of pneumothorax after blind needle insertion in the upper trapezius and posterior cervical area.
• Thoracic paraspinals: rib angles are more exposed in the middle of the thorax than in the lumbar spine. A realistic risk of complications is the pleural cavity.
• Piriformis: in most anatomical setups the sciatic nerve lies directly anterior to the piriformis, but there are some variations (the nerve passes through the muscle in a meaningful minority of the population). The ultrasound demonstrates the nerve and the muscle belly at the same time.
• Origin of the hamstring (ischial tuberosity): the sciatic nerve, and posterior femoral cutaneous nerve are very close to the proximal hamstring origin. In athletes and those with proximal hamstring tendinopathy, trigger points at the hamstring origin are clinically significant, but not a landmark-only site for needling.
• Pelvic floor: internal pelvic floor dry needling is performed on trigger points in the levator ani, obturator internus and other structures and must be performed with a good knowledge of pelvic anatomy and preferably ultrasound confirmation of needle position. Moldwin and Fariello (2013) thoroughly explained the clinical use of trigger point therapy for pelvic floor dysfunction, and the complexity of the region and the skill requirements.

The local twitch response is the sensation most closely linked to dry needling and is characterized by a small, involuntary muscle twitch that occurs when the needle is inserted into the taut band. Patients have reported it as a cramping, jumping or grabbing feeling. The first time it can be a surprise. It is not a bad sign, there is some evidence that it is related to better clinical outcomes, although the relationship is not a linear one.

Referred pain reproduction occurs frequently. Many patients report the familiar pain as it radiates down to the temple or behind the eye as a result of the accurate needle placement of a trapezius trigger point – the same pattern that led them to the clinic. This indicates that the needles are in place and helps to reassure patients once they have understood the significance of the procedure.

The first 24-48 hours post-treatment can include delayed onset muscle soreness that is comparable to exercise-induced delayed onset muscle soreness. Immediate relief is experienced by some patients, while others experience improvement within 2-3 days. It is common to experience fatigue on the day of the treatment and patients should be advised to avoid strenuous activity for the rest of the day. By the next day, most people are back to normal.

• Chronic myofascial pain where manual therapy has not been effective enough
• Recurrent muscle injuries and suspected fascial adhesion in athletes
• Patients with neck, shoulder, or hip pain with referred pain patterns
• People who have problems with their pelvic floor such as pelvic pain, urinary urgency or painful sex
• Patients who have had surgery and developed guarding patterns and secondary trigger points
• Patients with imaging (MRI or previous ultrasound) evidence of tendinopathy, calcification, or thickening of the fascia in addition to trigger point symptoms

• Active local infection or skin breakdown at the area to be treated
• Coagulation disorders or anticoagulant therapy (requires clinical judgment and physician consultation)
• Patient is extremely needle phobic and is unable to tolerate the procedure
• Pregnancy (abdominal and lumbopelvic needling is generally contraindicated, but check with your physician)
• Lymphedema in or around the treatment area
• Patients unable to give informed consent or who don’t understand the procedure

Dry needling should not be the initial treatment for all patients and the presence of trigger points does not indicate that needling is the next step. A detailed movement assessment and biomechanical evaluation frequently alters the treatment plan.

Dry needling is best used as part of a treatment episode and not as an isolated treatment. The typical treatment at NYDNRehab is the combination of needling with:

• Dynamic ultrasound assessment: the affected area is assessed with real-time ultrasound before any needling session, while the person is moving. This is to determine the target tissue, exclude contraindications and set a baseline for monitoring change. The same imaging helps to position the needle during the procedure.
• Movement and biomechanical analysis: gait analysis, scapular kinematics, hip stability testing and spine mobility screening are used to determine the mechanisms underlying the formation of trigger points. Needling a hypertonic piriformis will have more lasting effects if used in conjunction with hip stabilization exercises to decrease the loading of the piriformis muscle.
• If tendinopathy, calcification or fascial stiffness is diagnosed in conjunction with trigger points, focused or radial shockwaves may be applied at the same time or separately in the same session. The effect of needling and shockwave on tissue is an ongoing clinical research interest.
• EMTT and laser: NYDNRehab uses Extracorporeal magnetotransduction therapy and low level laser therapy for their potential to repair tissue and modulate pain when needling is not enough.
• Functional rehabilitation: the pattern of movement that caused the trigger point in the first place must be altered. This includes exercise prescription, neuromuscular re-education and progressive loading of the affected area as the acute pain subsides.

Palpation is the most common technique used for dry needling. The clinician uses his or her hands to feel for the taut band, estimates the depth, introduces the needle, and checks the location by listening to the patient and feeling the needle. This is good enough in simple anatomical areas where there is skilled experience.

NYDNRehab incorporates real time dynamic musculoskeletal ultrasound as a part of each needling treatment. This isn’t a marketing difference, it’s a procedural one. The clinician observes the tip of the needle during insertion, verifies the location of the needle within the target area and modifies the trajectory if adjacent structures (nerves, vessels, fascial layers) are closer than what surface anatomy would suggest. The imaging also documents the response of the tissue during the treatment – changes in the echogenicity of muscles, movement of the fascia, local hyperemia on Doppler – which are not palpable.

The clinic’s overall approach is focused and not about quantity. Less, more focused interventions, based on objective imaging and movement data, tend to be more lasting than repeated generalized interventions. This attitude is carried over into patient selection, treatment planning, and when to combine platelet-rich plasma or prolotherapy with needling to achieve a better result.