Myofascial Low Back Pain

  Myofascial syndrome is a common non-articular local musculoskeletal pain syndrome caused by myofascial trigger points located at muscle, fascia, or tendinous insertions.

          The most widely accepted theory of myofascial pain is the Integrated Trigger Point Hypothesis by Simons. This theory suggests that muscles will maintain a sarcomere contraction with decreased levels of adenosine triphosphate caused by a reduction in blood flow to the area. This reduction in blood flow depletes the muscles fibers of sufficient energy to return calcium to the sarcoplasmic reticulum, which then results in a ridged state where the muscles are unable to relax. This situation can increase a patients pain related to the myofasical trigger points due to an increase in metabolic demands which results in tissue hypoxia to the area and a release of noxious biochemical substances. These substances include neuropeptieds, cytokines, and catecholamines as well as a decrease in pH levels.

     Overuse, repetitive motions, reduced muscle activity from casting or prolonged splinting.

        Physical examination should begin with a gait evaluation, inspection for postural imbalances, pelvic asymmetry and leg length discrepancies. Palpation is most important to identify myofascial trigger points. It is imperative to identify whether there are just tender points along the painful region or if there are trigger points. These can be distinguished from one another because trigger points will cause referred pain patterns and tender spots will only produce local tenderness. Common muscles to present with trigger points include iliocostalis lumborum, longissimus thoracis, multifidus, quadrates lumborum and gluteus medius (Keeping in mind the iliocostalic lumborum originated from the medial and lateral sacral crest which can cause referred pain to the sacroiliac region). The diagnostic criteria for myofascial pain includes tender sports in a taut band, predicted pain referral pattern, patient pain recognized on tender point palpation and limited range of motion. Travell and Simons identified a tender spot in a taut band in 65% of cases and is suggested as the most sensitive and specific of all the diagnostic criteria.

        Many different techniques have been used to treat myofascial pain including: pharmacological management, dry needling, physical therapy modalities, myofascial release, injection therapies, and alternative medicine. Malanga & Cruz Colon, 2010, declare the most important concept when treating myofascial pain is to treat the underlying etiologic pathology responsible for the trigger points, rather than the trigger points themselves. In many cases they have found the active trigger point to deactivate once the underlying pathology is effectively treated.

·         Manual therapy

         Manual therapy includes myofascial release, deep pressure massage, osteopathic manipulative treatment, and a technique called “spray and stretch.” These techniques are initially used to treat myofascial pain before more invasive approaches are attempted such as dry needling or injections. “Spray and stretch” was described by Simons as a technique used to passively stretch the muscles in which trigger points existed while simultaneously applying a vaporized cooling liquid spray to allow a pain-relieving affect so the muscle to be stretched passively towards normal length and the trigger point in inactivated.

·         Modalities

        Ultra sound, iontophoresis, and high-voltage galvanic stimulation are often used by physical therapist to treat myofascial pain, but none of these are supported by scientific research in their success at eliminated trigger points.

·         Injection and dry needling

       Best available research evidence supports trigger point injection and dry needling as an effective treatment for trigger points. This treatment approach is tried after unsuccessful attempts at treatment with physical therapy, when the patient fails to respond to medications, or when a joint in mechanically locked. Needle size is usually 25-27 gauge, while needle length is most common between .75 to 2.5 inches depending on the depth of the muscle through the subcutaneous tissue. The recommended volume of an anesthetic (frequently Lidocaine) is between 0.5 to 2 mL per trigger point. Travell and Simons recommend full active range of motion after the muscle is injected to allow for full shortened and fully lengthened position. A randomized control trial was carried out by Ay and colleagues 2009 that assessed the effects of anesthetic injection and dry needling and found both of these injection methods to relax taut bands, decrease pain, increase local blood flow, improve range of motion and cause fibrotic scar formation on trigger points.

·         Herbal medications

      Natural medications such as lavender, rosemary, passionflower, lemon balm and marijuana all include linalool which has successfully treated trigger points. Linalool compound inhibits end plate activity by reducing acetylcholine release and modifying nicotinic acetylcholine receptors.