Equine Myofascial Pain and Dry Needling

Written by Dr. Maria Calatayud Bonilla, PT, MsC, PhD, Instructor of the Equine Dry Needling Course, Myopain Seminars, LLC.

“We tend to think that musculoskeletal pain involves a disabling injury during its healing process: enthesitis, tendinitis, desmitis, fibrillar tears, fractures… In this way, a tendon injury can halt an athlete’s activity for a variable period of time, depending on the type of injury. This occurs in humans and horses alike. However, within musculoskeletal pain, myofascial pain is not entirely limiting.” [1]

Three years after my first post on Onlinepethealth, I am thrilled to continue discussing equine myofascial pain, always grounded in the latest scientific evidence.

In my previous post, I addressed the high prevalence of myofascial pain in humans, defining trigger points (TrPs) and describing their clinical signs:

 “TrPs are hypersensitive nodules located within a taut band of skeletal muscle. According to Simons D.G. [2], the three minimum clinical diagnostic criteria are: the presence of a taut band, a painful hypersensitive spot within it, and referred pain recognized by the patient upon stimulation of the sensitive spot. Additionally, six confirmatory characteristics should be present: local twitch response (LTR) when palpating TrPs, the ‘jump sign’ (a flight reaction from the patient), recognition of the pain by the patient, predictable referred pain patterns, muscle weakness or tension, and pain during muscle contraction or stretching [3].”

I also highlighted the critical role of palpation skills and clinician experience for accurate diagnosis. This remains true: scientific evidence consistently identifies these two factors as essential for reliable outcomes [4].

As I mentioned, myofascial pain is not entirely limiting—it may not paralyze a patient’s activity, but it often eludes accurate diagnosis by clinicians.

Myofascial pain might be the missing piece of the puzzle for proper diagnosis [5]. During my four years of doctoral research at the university, I’ve learned many lessons. One of the most important is that managing myofascial pain in animals is highly complex. Myofascial pain is not limited to localized muscle tenderness; it affects functionality and can become chronic. The role of central sensitization (CS) in chronic pain processes cannot be underestimated. In humans, CS amplifies pain hypersensitivity, lowers pressure pain thresholds (PPT), and disrupts temporal summation mechanisms, making pain feel as though tissue damage is present [6].

While a horse’s behavior may reflect its pain state, assessing chronicity in the absence of evidence of tissue damage remains a significant challenge. Chronic cervical pain [7] and back pain in equines are common pathologies described decades ago [8]. Ridgeway proposed a connection between myofascial pain syndrome (MPS) and chronic pain after observing difficulties in identifying lameness associated with chronic pain using conventional therapeutic approaches. Moreover, we cannot overlook the comorbid nature of myofascial pain in equines: lameness, thoracolumbosacral pain, and limited range of motion (ROM) often coexist [9].

Without a deep understanding of myofascial pain, many horses fail to receive proper pain management. Imaging techniques, while valuable, do not provide relevant data for detecting TrPs. Although LTRs have been observed via ultrasound, this requires advanced technology often limited to research rather than clinical settings. Similarly, electromyography (EMG) can detect spontaneous motor endplate activity associated with TrPs [10]  but remains a tool primarily for laboratory use. Ultimately, we return to the clinician’s expertise and knowledge as the cornerstone of effective diagnosis.

Dry needling (DN) is a highly specialized technique for treating TrPs, involving the insertion of a fine, sterile, filiform needle through the skin and into the TrP to deactivate it. It is the gold standard for treating myofascial pain, supported by extensive scientific evidence in human medicine. In veterinary medicine, studies   [11]—while not explicitly focused on DN—demonstrated that needle electrostimulation of a TrP in the peroneus longus muscle increased PPT values without affecting other physiological parameters.

In equine research, my team has explored several aspects: the reliability of TrP palpation, the effects of training on TrP tenderness, the reliability of algometry in assessing TrP pain, and the effectiveness of DN in treating local pain caused by TrPs in the equine brachiocephalic muscle [12, 13,14,15,16,17].

Between research and teaching, equine myofascial pain remains a daily focus for me. I believe training future professionals in this area is crucial to ensuring a key piece of the puzzle in diagnosing musculoskeletal pathologies in horses is not overlooked—whether the horse is used in sports or for other purposes.

For several years, I have been an instructor of equine dry needling courses alongside my colleague, María Resano. Our goal is to equip students with the knowledge and skills necessary to address cases where conventional treatments fall short. The course is designed for veterinarians and physical therapists, interested in equine myofascial pain management. We base our curriculum on the latest scientific evidence and are proud to offer training that adheres to the highest standards of quality and safety—for both clinicians and horses.

Myopain Seminars, a leading institute in myofascial pain management, offers dry needling courses worldwide. We are delighted to travel globally, helping horses—those remarkable animals that bring so much happiness to our lives.

REFERENCES

1. Myopain Seminars
2. Simons DG. New views of myofascial trigger points: etiology and diagnosis. Arch Phys Med Rehabil 2008;89:157–9.
3. Cagnie, B., Dewitte, V., Barbe, T., Timmermans, F., Delrue, N., & Meeus, M. (2013). Physiologic effects of dry needling. Current pain and headache reports, 17(8), 348.
4. Barbero, M., Bertoli, P., Cescon, C., Macmillan, F., Coutts, F., & Gatti, R. (2012). Intra-rater reliability of an experienced physiotherapist in locating myofascial trigger points in upper trapezius muscle. Journal of Manual & Manipulative Therapy, 20(4), 171-177.
5. Story, M. R., Haussler, K. K., Nout-Lomas, Y. S., Aboellail, T. A., Kawcak, C. E., Barrett, M. F., … & McIlwraith, C. W. (2021). Equine cervical pain and dysfunction: pathology, diagnosis and treatment. Animals, 11(2), 422.
6. Serrano-Muñoz, D., Gómez-Soriano, J., Ávila-Martín, G., Galán-Arriero, I., Romero-Muñoz, L. M., Taylor, J. S., & Barriga-Martín, A. (2016). Sensibilización central al dolor en pacientes con síndrome del latigazo cervical: una revisión. Revista Latinoamericana de Cirugía Ortopédica, 1(3), 102-107.
7. Rombach, N. (2013). The structural basis of equine neck pain. Michigan State University.
8. Ridgway, K. (1999). Acupuncture as a treatment modality for back problems. Veterinary Clinics of North America: Equine Practice, 15(1).
9. Greve, L., Dyson, S., & Pfau, T. (2017). Alterations in thoracolumbosacral movement when pain causing lameness has been improved by diagnostic analgesia. The Veterinary Journal, 224, 55-63.
10. Macgregor, J., & von Schweinitz, D. G. (2006). Needle electromyographic activity of myofascial trigger points and control sites in equine cleido-brachialis muscle–an observational study. Acupuncture in Medicine, 24(2), 61-70.
11. Altug, M. E., & Tas, A. (2010). The effects of peroneus longus trigger point stimulation on the pain threshold in dogs. The Indian Veterinary Journal.
12. Nemery, E., Gabriel, A., Cassart, D., Bayrou, C., Piret, J., Antoine, N., … & Carvalho, C. (2016, December). Proceedings of the 9th international symposium on veterinary rehabilitation and physical therapy. In Acta Veterinaria Scandinavica (Vol. 58, No. 2, p. 85). BioMed Central.
13. Calatayud-Bonilla, M., Resano-Zuazu M. (2016). Improvement of myofascial pain in equine brachiocephalicus muscle using dry needling technique, a clinical commentary. (58; suppl2, A5).
14. Calatayud-Bonilla M., Resano-Zuazu M., Segura-Orti E. (2018). Intrarater reliability in locating myofascial trigger point in the equine brachiocephalicus muscle. Poster presented at: 28th Physiotherapy Simposium EUF ONCE. Fascia Scientifific Advances. Madrid, Spain.
15. Calatayud-Bonilla, M., Resano-Zuazu, M., Segura-Ortí, E. (2019) Pain pressure thresholds for evaluating myofascial pain in the equine brachiocephalicus muscle. Revista Fisioterapia Invasiva/Journal of Invasive Techniques in Physical Therapy, 2(02), 114-114.
16. Calatayud-Bonilla, M., Resano-Zuazu, M., Prades, M. (2020) Painful response to trigger points palpation in the equine brachiocephalicus muscle: a preliminary study. Poster presented at: 30 Jornadas de Fisioterapia de la ONCE: Síndrome de dolor miofascial y puntos gatillo miofasciales: 20 años de evolución; 2020 Marzo 6-7; Madrid, Spain.
17. Calatayud-Bonilla, M., Prades, M., Carmona, J. Is dry needling an effective technique to treat pain from trigger points in the equine brachiocephalic muscle? Poster presented in the 5th Scientific Meeting of the European College of Veterinary Sports Medicine and Rehabilitation (ECVSMR), University of Córdoba, Spain.