Myofascial Trigger Points – the sports person’s nemesis?
If you have played sport you are likely to have experienced pain at some stage, whether it is from direct trauma, overactivity or beginning sport after a prolonged period of rest. Usually the pain disappears. However, if you’re unlucky this pain may persist to become chronic pain (pain defined as lasting longer than six weeks). But what is causing this pain?
There are three groups of pain-producing structures causing musculoskeletal pain:
- Joints (including ligaments)
- Muscles (including tendons and fascia)
- Neural structures (relating to nerves)
Pain perceived by a patient can arise from either one of these structures of a combination of two or more of them. To further confuse us, it is often difficult for the patient to differentiate where the pain is coming from, as all too often muscle pain can be mistaken for nerve pain.
Pain from muscles and myofascial trigger points (MTrPs)
A myofascial trigger point (MTrP) has been defined as a hyperirritable spot in skeletal muscle that is associated with a hypersensitive palpable nodule in a taut band (Travel and Simons, 1999). In other words a myofascial trigger point is a zone of intense pain in a hardened muscle band that refers (triggers) pain distantly when stimulated (Gerwin et al, 2004). Perpendicular palpation to the muscle fibre direction may reveal a taut band. A taut band feels like a rope that may extend from one end of the muscle, or there may be a number of taut bands within one muscle itself. Palpation of the taut band may reveal a nodule that is exquisitely tender. Firm pressure on this nodule may reproduce the patient’s pain, and recognition of this pain, or referred pain sensations from this muscle, is considered one of the diagnostic criteria for MTrPs. A local twitch response may also be elicited on palpation of the taut band. This is a brief contraction of the taut band (Dommerholt and Issa, 2003).
MTrPs may be defined as being active or latent. Active MTrPs cause pain at rest. Occasionally they can cause night pain and interfere with sleep. They display the local twitch response on palpation, as well as reproducing the patient’s pain or a referred pain pattern that is similar to patient’s pain complaint. Latent MTrPs is a point in the muscle that is locally tender, but does not refer pain or elicit the local twitch response.
In addition to pain, MTrPs may cause functional limitations in the muscle, such as muscle weakness, fatigue with activity, loss of muscle coordination, decreased ability to carry out particular muscular tasks, loss of muscle endurance and joint stiffness. MTrPs are also frequently related to muscle shortening and reduced range of motion (Brukner and Khan, 2007).
The pain from MTrPs is often confused for nerve pain. It usually feels deep, dull and poorly localised. It may be a constant or deep ache, but is rarely throbbing or burning in nature.
So the pain in my head is not actually coming from my head?!
Since one of the characteristics of MTrPs is referred pain distant from the source of the pain, pain experienced in the head may be referring from an MTrP in the upper trapezius or neck muscles for example. Similarly, pain in the hamstrings may not be caused by hamstrings dysfunction, but rather from MTrPs in the gluteal (buttock) muscles.
What causes MTrPs?
Characteristically, MTrP pain is aggravated by strenuous use of the muscles, eccentric muscle exercise (defined as muscle contraction when the muscle is in a lengthened position), overloading and overcompensation of muscles during prolonged poor postures, repetitive contractions of the involved muscle, anxiety and tension.
Research has showed biochemical and physiological changes in the taut band of humans.
So you think you have MTrPs? What can you do?
Fortunately, MTrPs are relatively easy to treat. The most difficult part is actually recognising that your pain is caused by MTrPs. Chartered Physiotherapists are excellent investigators and practitioners when it comes to MTrPs. There are many effective treatments, and this is an area which is fast growing in research interest. The MTrP must be released, either using digital pressure or with dry needling to restore the local circulation, decrease pain and
facilitate range of motion and functional movement patterns. Of these treatments, dry needling has proven to be the most successful. This technique employs solid filament needles, similar to those used in acupuncture, which are inserted into the taut band within the muscle. After dry needling the patient is instructed to stretch the muscle, address any predisposing factors such as poor posture and follow the instructions of the Chartered Physiotherapist with regard to returning to sporting activity and strengthening of appropriate muscles as necessary.
Image: Figure 1. Circles indicate the MTrPs and the light and dark grey regions indicate the typical referral patterns (Dommerholt J, Issa T, 2003)
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References:
Brukner P and Khan K 2007 Clinical Sports Medicine. Pain: where is it coming from? pp 27 – 33. 3rd edn. McGraw Hill: Sydney
Dommerholt J, Issa T 2003 Fibromyalgia Syndrome: A Practitioner’s Guide to Treatment. Differential Diagnosis: Myofascial Pain Syndrome pp 1 – 37. Churchill Livingstone: Edinburgh
Gerwin RD, Dommerholt J, Shah J 2004 The Expansion of Simons’ Integrated Hypothesis of Trigger Point Formation. Current Pain and Headache Reports 8: 468 – 475
Travell JG, Simons DF 1999 Myofascial Pain and Dysfunction. The Trigger Point Manual. Vol. 1. 2nd edn. Williams and Wilkins: Baltimore