Abstract
Sikdar S, Shah JP, Gebreab T, Yen R-H, Gilliams E, Danoff J, Gerber LH. Novel applications
of ultrasound technology to visualize and characterize myofascial trigger points and
surrounding soft tissue.
Objective
To apply ultrasound (US) imaging techniques to better describe the characteristics
of myofascial trigger points (MTrPs) and the immediately adjacent soft tissue.
Design
Four sites in each patient were labeled based on physical examination as active myofascial
trigger points (A-MTrPs; spontaneously painful), latent myofascial trigger points
(L-MTrPs; nonpainful), or normal myofascial tissue. US examination was performed on
each subject by a team blinded to the physical findings. A 12∼5MHz US transducer was
used. Vibration sonoelastography (VSE) was performed by color Doppler variance imaging
while simultaneously inducing vibrations (∼92Hz) with a handheld massage vibrator.
Each site was assigned a tissue imaging score as follows: 0, uniform echogenicity
and stiffness; 1, focal hypoechoic region with stiff nodule; 2, multiple hypoechoic
regions with stiff nodules. Blood flow in the neighborhood of MTrPs was assessed using
Doppler imaging. Each site was assigned a blood flow waveform score as follows: 0,
normal arterial flow in muscle; 1, elevated diastolic flow; 2, high-resistance flow
waveform with retrograde diastolic flow.
Setting
Biomedical research center.
Participants
Subjects (N=9) meeting Travell and Simons' criteria for MTrPs in a taut band in the
upper trapezius.
Interventions
Not applicable.
Main Outcome Measures
MTrPs were evaluated by (1) physical examination, (2) pressure algometry, and (3)
three types of US imaging including gray-scale (2-dimensional [2D] US), VSE, and Doppler.
Results
MTrPs appeared as focal, hypoechoic regions on 2D US, indicating local changes in
tissue echogenicity, and as focal regions of reduced vibration amplitude on VSE, indicating
a localized, stiff nodule. MTrPs were elliptical, with a size of .16±.11cm2. There were no significant differences in size between A-MTrPs and L-MTrPs. Sites
containing MTrPs were more likely to have a higher tissue imaging score compared with
normal myofascial tissue (P<.002). Small arteries (or enlarged arterioles) near A-MTrPs showed retrograde flow
in diastole, indicating a highly resistive vascular bed. A-MTrP sites were more likely
to have a higher blood flow score compared with L-MTrPs (P<.021).
Conclusions
Preliminary findings show that, under the conditions of this investigation, US imaging
techniques can be used to distinguish myofascial tissue containing MTrPs from normal
myofascial tissue (lacking trigger points). US enables visualization and some characterization
of MTrPs and adjacent soft tissue.
Key Words
List of Abbreviations:
A-MTrP (active myofascial trigger point), L-MTrP (latent myofascial trigger point), MPS (myofascial pain syndrome), MRE (magnetic resonance elastography), MTrP (myofascial trigger point), Po2 (partial pressure of oxygen), PPT (pain pressure threshold), RI (resistive index), 3D (3-dimensional), 2D (2-dimensional), US (ultrasound), VSE (vibration sonoelastography)To read this article in full you will need to make a payment
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References
- Classification, epidemiology, and natural history of myofascial pain syndrome.Curr Pain Headache Rep. 2001; 5: 412-420
- Male and female chronic pain patients categorized by DSM-III psychiatric diagnostic criteria.Pain. 1986; 26: 181-197
- Travell and Simons' myofascial pain and dysfunction: the trigger point manual.2nd ed. Williams and Wilkins, Baltimore1999
- The role of myofascial trigger points in musculoskeletal pain syndromes of the head and neck.Curr Pain Headache Rep. 2007; 11: 365-372
- The impact of latent trigger points on regional muscle function.Curr Pain Headache Rep. 2008; 12: 344-349
- Myofascial trigger points and their relationship to headache clinical parameters in chronic tension-type headache.Headache. 2006; 46: 1264-1272
- Physical findings in patients with chronic intractable benign pain of the neck and/or back.Pain. 1989; 37: 279-287
- Trigger point evaluation in migraine patients: an indication of peripheral sensitization linked to migraine predisposition?.Eur J Neurol. 2006; 13: 244-249
- Prevalence of myofascial pain in general internal medicine practice.West J Med. 1989; 151: 157-160
- Interexaminer reliability of the palpation of trigger points in the trunk and lower limb muscles.Arch Phys Med Rehabil. 2000; 81: 258-264
- Biochemicals associated with pain and inflammation are elevated in sites near to and remote from active myofascial trigger points.Arch Phys Med Rehabil. 2008; 89: 16-23
- An in vivo microanalytical technique for measuring the local biochemical milieu of human skeletal muscle.J Appl Physiol. 2005; 99: 1977-1984
- Identification and quantification of myofascial taut bands with magnetic resonance elastography.Arch Phys Med Rehabil. 2007; 88: 1658-1661
- New views of myofascial trigger points: etiology and diagnosis.Arch Phys Med Rehabil. 2008; 89: 157-159
- Assessment of myofascial trigger points (MTrPs): a new application of ultrasound imaging and vibration sonoelastography.Conf Proc IEEE Eng Med Biol Soc. 2008; 1: 5585-5589
- Myofascial pain disorders: theory to therapy.Drugs. 2004; 64: 45-62
- Ultrasound imaging distinguishes between normal and weak muscle.Arch Phys Med Rehabil. 2004; 85: 980-986
- Diagnostic ultrasound: its use in the evaluation of muscle.Arch Phys Med Rehabil. 1984; 65: 129-131
- Ultrasound sector scanning used to define changes in muscle configuration.Scand J Rehabil Med. 1989; 21: 209-212
- Ultrasonic technique for imaging tissue vibrations: preliminary results.Ultrasound Med Biol. 2005; 31: 221-232
- Research interface on a programmable ultrasound scanner.Ultrasonics. 2008; 48: 159-168
- Three-dimensional sonoelastography: principles and practices.Phys Med Biol. 2000; 45: 1477-1494
- Sonoelasticity imaging: theory and experimental verification.J Acoust Soc Am. 1995; 97: 3875-3886
- Sonoelastic determination of human skeletal muscle elasticity.J Biomech. 1995; 28: 1145-1154
- Human muscle hardness assessment during incremental isometric contraction using transient elastography.J Biomech. 2005; 38: 1543-1550
- Lesions of rat skeletal muscle after local block of acetylcholinesterase and neuromuscular stimulation.J Appl Physiol. 2003; 94: 2494-2501
- Morphologische untersuchung an triggerpunkten.Manuelle Medizin. 1996; 34: 256-262
- Morphology and histochemistry of myogelosis.Clin Anat. 1999; 12: 266-271
- The myofascial trigger point region: correlation between the degree of irritability and the prevalence of endplate noise.Am J Phys Med Rehabil. 2007; 86: 183-189
- Central modulation of pain evoked from myofascial trigger point.Clin J Pain. 2007; 23: 440-448
- Uncovering the biochemical milieu of myofascial trigger points using in vivo microdialysis: an application of muscle pain concepts to myofascial pain syndrome.J Bodyw Mov Ther. 2008; 12: 371-384
- Ability of magnetic resonance elastography to assess taut bands.Clin Biomech (Bristol, Avon). 2008; 23: 623-629
- Intramuscular pressure and muscle blood flow in supraspinatus.Eur J Appl Physiol Occup Physiol. 1988; 58: 219-224
- Tissue oxygen measurement and 31P magnetic resonance spectroscopy in patients with muscle tension and fibromyalgia.Rheumatol Int. 1997; 16: 175-180
Article info
Footnotes
Supported by the Intramural Research Program, National Institutes of Health (NIH), and the Clinical Center and Office of the Director, NIH.
No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit on the authors or on any organization with which the authors are associated.
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Published by Elsevier Inc.