Myofascial trigger points and innervation zone locations in upper trapezius muscles

Marco Barbero, Corrado Cescon, Andrea Tettamanti, Vittorio Leggero, Fiona Macmillan, Fiona Coutts, Roberto Gatti, Marco Barbero, Corrado Cescon, Andrea Tettamanti, Vittorio Leggero, Fiona Macmillan, Fiona Coutts, Roberto Gatti

Abstract

Background: Myofascial trigger points (MTrPs) are hyperirritable spots located in taut bands of muscle fibres. Electrophysiological studies indicate that abnormal electrical activity is detectable near MTrPs. This phenomenon has been described as endplate noise and it has been purported to be associated MTrP pathophysiology. Thus, it is suggested that MTrPs will be overlap the innervation zone (IZ). The purpose of this work was to describe the location of MTrPs and the IZ in the right upper trapezius.

Methods: We screened 71 individuals and eventually enrolled 24 subjects with neck pain and active MTrPs and 24 neck pain-free subjects with latent MTrPs. Surface electromyography (sEMG) signals were detected using an electrode matrix during isometric contraction of the upper trapezius. A physiotherapist subsequently examined the subject's trapezius to confirm the presence of MTrPs and establish their location. IZ locations were identified by visual analysis of sEMG signals. IZ and MTrPs locations were described using an anatomical coordinate system (ACS), with the skin area covered by the matrix divided into four quadrants.

Results: No significant difference was observed between active and latent MTrPs locations (P = 0.6). Forty-five MTrPs were in the third quadrant of the ACS, and 3 were included in second quadrant. IZs were located approximately midway between the seventh cervical vertebrae and the acromial angle in a limited area in the second and third quadrants. The mean distance between MTrP and IZ was 10.4 ± 5.8 mm.

Conclusions: According to the acquired results, we conclude that IZ and MTrPs are located in well-defined areas in upper trapezius muscle. Moreover, MTrPs in upper trapezius are proximally located to the IZ but not overlapped.

Figures

Figure 1
Figure 1
Experimental setup. Subjects sat in a custom made chair with a load cell connected to the right handle and were connected to an electrode matrix (model ELSCH064, designed by LISiN at Politecnico di Torino and manufactured by OT Bioelectronica, Torino, Italy) placed on the upper trapezius. They viewed the visual feedback device (MISO II, LISiN, OT Bioelettronica, Torino, Italy) during the experiment.
Figure 2
Figure 2
Electrode matrix placement. The red dot indicates an MTrP in the upper trapezius and the blue line shows the IZ location over the area covered by the electrode matrix. The IZ was typically located medially to the Y-axis. TrP-IZ is the distance between SP in the MTrP region and the IZ line. For each of the five columns of the matrix EMG signals are reported and IZ locations indicated using a blue arrow. The IZ location was detected where EMG signals showed minimal amplitude and/or phase reversal. AC, acromial angle; C7, spinous process of the seventh vertebrae; SP, spot tenderness.
Figure 3
Figure 3
Graphical representation of MTrPs and IZ location in the upper trapezius according to the ACS in 48 subjects. A) Active MTrPs are represented as green circles and latent as white circles, and the colours indicate MTrP spatial densities (dark red spot indicates high trigger point density). B) IZ distribution, colour represents IZ density (dark blue area indicates high IZ density). C) Each IZ loction is represented by different colours link IZs detected on the matrix columns. AC, acromial angle; C7, spinous process of the seventh cervical vertebrae.

References

    1. Abasolo L, Blanco M, Bachiller J, Candelas G, Collado P, Lajas C, Revenga M, Ricci P, Lazaro P, Aguilar MD. et al.A health system program to reduce work disability related to musculoskeletal disorders. Ann Intern Med. 2005;143(6):404–414. doi: 10.7326/0003-4819-143-6-200509200-00005.
    1. Mense S, Simons DG, Russell IJ. Muscle pain : understanding its nature, diagnosis, and treatment. Baltimore, Md: Lippincott Williams & Wilkins; 2000.
    1. Han SC, Harrison P. Myofascial pain syndrome and trigger-point management. Reg Anesth. 1997;22(1):89–101. doi: 10.1016/S1098-7339(06)80062-3.
    1. Travell JG, Simons DG. Myofascial pain and dysfunction: the trigger point manual. Baltimore; London: Williams & Wilkins; 1983.
    1. Simons D. Clinical and etiological update of myofascial pain from trigger points. J Musculoskeletal Pain. 1996;4:97–125. doi: 10.1300/J094v04n03_10.
    1. Hong CZ, Simons DG. Pathophysiologic and electrophysiologic mechanisms of myofascial trigger points. Arch Phys Med Rehabil. 1998;79(7):863–872. doi: 10.1016/S0003-9993(98)90371-9.
    1. Kuan TS. Current studies on myofascial pain syndrome. Curr Pain Headache Rep. 2009;13(5):365–369. doi: 10.1007/s11916-009-0059-0.
    1. Simons DG. Do endplate noise and spikes arise from normal motor endplates? Am J Phys Med Rehabil. 2001;80(2):134–140. doi: 10.1097/00002060-200102000-00012.
    1. Simons DG. New views of myofascial trigger points: etiology and diagnosis. Arch Phys Med Rehabil. 2008;89(1):157–159. doi: 10.1016/j.apmr.2007.11.016.
    1. Simons DG, Hong CZ, Simons LS. Endplate potentials are common to midfiber myofacial trigger points. Am J Phys Med Rehabil. 2002;81(3):212–222. doi: 10.1097/00002060-200203000-00010.
    1. Coërs C, Woolf AL. The innervation of muscle. Oxford: Blackwell Scientific Publications, Inc; 1959.
    1. Kim MW, Kim JH, Yang YJ, Ko YJ. Anatomic localization of motor points in gastrocnemius and soleus muscles. Am J Phys Med Rehabil. 2005;84(9):680–683. doi: 10.1097/01.phm.0000176341.85398.a9.
    1. Parratte B, Tatu L, Vuillier F, Diop M, Monnier G. Intramuscular distribution of nerves in the human triceps surae muscle: anatomical bases for treatment of spastic drop foot with botulinum toxin. Surg Radiol Anat. 2002;24(2):91–96. doi: 10.1007/s00276-002-0022-9.
    1. Prodanov D, Thil MA, Marani E, Delbeke J, Holsheimer J. Three-dimensional topography of the motor endplates of the rat gastrocnemius muscle. Muscle Nerve. 2005;32(3):292–302. doi: 10.1002/mus.20378.
    1. Hubbard DR, Berkoff GM. Myofascial trigger points show spontaneous needle EMG activity. Spine (Phila Pa 1976) 1993;18(13):1803–1807. doi: 10.1097/00007632-199310000-00015.
    1. Kuan TS, Hong CZ, Chen JT, Chen SM, Chien CH. The spinal cord connections of the myofascial trigger spots. Eur J Pain. 2007;11(6):624–634. doi: 10.1016/j.ejpain.2006.10.001.
    1. Liley AW. An investigation of spontaneous activity at the neuromuscular junction of the rat. J Physiol. 1956;132(3):650–666.
    1. Kuan TS, Chen JT, Chen SM, Chien CH, Hong CZ. Effect of botulinum toxin on endplate noise in myofascial trigger spots of rabbit skeletal muscle. Am J Phys Med Rehabil. 2002;81(7):512–520. doi: 10.1097/00002060-200207000-00008. quiz 521–513.
    1. Mense S, Simons DG, Hoheisel U, Quenzer B. Lesions of rat skeletal muscle after local block of acetylcholinesterase and neuromuscular stimulation. J Appl Physiol. 2003;94(6):2494–2501.
    1. Simons DG, Stolov WC. Microscopic features and transient contraction of palpable bands in canine muscle. Am J Phys Med. 1976;55(2):65–88.
    1. Shah JP, Gilliams EA. 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(4):371–384. doi: 10.1016/j.jbmt.2008.06.006.
    1. Shah JP, Phillips TM, Danoff JV, Gerber LH. An in vivo microanalytical technique for measuring the local biochemical milieu of human skeletal muscle. J Appl Physiol. 2005;99(5):1977–1984. doi: 10.1152/japplphysiol.00419.2005.
    1. Simons DG. Review of enigmatic MTrPs as a common cause of enigmatic musculoskeletal pain and dysfunction. J Electromyogr Kinesiol. 2004;14(1):95–107. doi: 10.1016/j.jelekin.2003.09.018.
    1. Soares A, Andriolo RB, Atallah AN, da Silva EM. Botulinum toxin for myofascial pain syndromes in adults. Cochrane Database Syst Rev. 2012;4:CD007533.
    1. Delnooz CC, van de Warrenburg BP. Current and future medical treatment in primary dystonia. Ther Adv Neurol Disord. 2012;5(4):221–240. doi: 10.1177/1756285612447261.
    1. Barbero M, Gatti R, Lo Conte L, Macmillan F, Coutts F, Merletti R. Reliability of surface EMG matrix in locating the innervation zone of upper trapezius muscle. J Electromyogr Kinesiol. 2011;21(5):827–833. doi: 10.1016/j.jelekin.2011.05.013.
    1. Masuda T, Miyano H, Sadoyama T. The distribution of myoneural junctions in the biceps brachii investigated by surface electromyography. Electroencephalogr Clin Neurophysiol. 1983;56(6):597–603. doi: 10.1016/0013-4694(83)90027-5.
    1. Merletti R, Farina D, Gazzoni M. The linear electrode array: a useful tool with many applications. J Electromyogr Kinesiol. 2003;13(1):37–47. doi: 10.1016/S1050-6411(02)00082-2.
    1. Saitou K, Masuda T, Michikami D, Kojima R, Okada M. Innervation zones of the upper and lower limb muscles estimated by using multichannel surface EMG. J Hum Ergol (Tokyo) 2000;29(1–2):35–52.
    1. Bogduk N, McGuirk B. Medical management of acute and chronic neck pain: an evidence-based approach. Edinburgh: Elsevier; 2006.
    1. Myburgh C, Larsen AH, Hartvigsen J. A systematic, critical review of manual palpation for identifying myofascial trigger points: evidence and clinical significance. Arch Phys Med Rehabil. 2008;89(6):1169–1176. doi: 10.1016/j.apmr.2007.12.033.
    1. Merletti R, Farina D, Granata A. Non-invasive assessment of motor unit properties with linear electrode arrays. Electroencephalogr Clin Neurophysiol Suppl. 1999;50:293–300.
    1. Johnson G, Bogduk N, Nowitzke A, Huose D. Anatomy and actions of the trapezius. Clin Biomech. 1994;9:44–50. doi: 10.1016/0268-0033(94)90057-4.
    1. Kuan TS, Hsieh YL, Chen SM, Chen JT, Yen WC, Hong CZ. The myofascial trigger point region: correlation between the degree of irritability and the prevalence of endplate noise. Am J Phys Med Rehabil. 2007;86(3):183–189. doi: 10.1097/PHM.0b013e3180320ea7.
    1. Fischer AA. Reliability of the pressure algometer as a measure of myofascial trigger point sensitivity. Pain. 1987;28(3):411–414. doi: 10.1016/0304-3959(87)90074-1.
    1. Sciotti VM, Mittak VL, DiMarco L, Ford LM, Plezbert J, Santipadri E, Wigglesworth J, Ball K. Clinical precision of myofascial trigger point location in the trapezius muscle. Pain. 2001;93(3):259–266. doi: 10.1016/S0304-3959(01)00325-6.
    1. Fernandez-de-las-Penas C, Alonso-Blanco C, Miangolarra JC. Myofascial trigger points in subjects presenting with mechanical neck pain: a blinded, controlled study. Man Ther. 2007;12(1):29–33. doi: 10.1016/j.math.2006.02.002.
    1. Barbero M, Bertoli P, Cescon C, Macmillan F, Coutts F, Gatti R. Intra-rater reliability of an experienced physiotherapist in locating myofascial trigger points in upper trapezius muscle. J Man Manipulative Ther. 2012;20(4):171–177. doi: 10.1179/2042618612Y.0000000010.
    1. Njoo KH, Van der Does E. The occurrence and inter-rater reliability of myofascial trigger points in the quadratus lumborum and gluteus medius: a prospective study in non-specific low back pain patients and controls in general practice. Pain. 1994;58(3):317–323. doi: 10.1016/0304-3959(94)90125-2.
    1. Wolfe F, Simons DG, Fricton J, Bennett RM, Goldenberg DL, Gerwin R, Hathaway D, McCain GA, Russell IJ, Sanders HO. et al.The fibromyalgia and myofascial pain syndromes: a preliminary study of tender points and trigger points in persons with fibromyalgia, myofascial pain syndrome and no disease. J Rheumatol. 1992;19(6):944–951.
    1. Alonso-Blanco C, de-la-Llave-Rincon AI, Fernandez-de-las-Penas C. Muscle trigger point therapy in tension-type headache. Expert Rev Neurother. 2012;12(3):315–322. doi: 10.1586/ern.11.138.
    1. Bron C, Dommerholt J, Stegenga B, Wensing M, Oostendorp RA. High prevalence of shoulder girdle muscles with myofascial trigger points in patients with shoulder pain. BMC Musculoskelet Disord. 2011;12:139. doi: 10.1186/1471-2474-12-139.
    1. Itza F, Zarza D, Serra L, Gomez-Sancha F, Salinas J, Allona-Almagro A. [Myofascial pain syndrome in the pelvic floor: a common urological condition] Actas Urol Esp. 2010;34(4):318–326. doi: 10.1016/S2173-5786(10)70077-9.
    1. Skootsky SA, Jaeger B, Oye RK. Prevalence of myofascial pain in general internal medicine practice. West J Med. 1989;151(2):157–160.
    1. Ramachandran M, Eastwood DM. Botulinum toxin and its orthopaedic applications. J Bone Joint Surg Br. 2006;88(8):981–987.

Source: PubMed

스폰서 및 공동 작업자

건강 상태

약물 개입

3
구독하다