Myofascial pain syndrome is a common chronic
pain disorder that can affect various parts of the body. Myofascial pain syndrome is characterized
by presence of hyperirritable spots located in skeletal muscle called trigger points.
A trigger point can be felt as a band or a nodule of muscle with harder than normal consistency.
Palpation of trigger points may elicit pain in a different area of the body. This is called
referred pain. Referred pain makes diagnosis difficult as the pain mimics symptoms of more
well-known common conditions. For example, trigger point related pain in the head and
neck region may manifest as tension headache, temporomandibular joint pain, eye pain, or
tinnitus. Symptoms of myofascial pain syndrome include
regional, persistent pain, commonly associated with limited range of motion of the affected
muscle. The pain is most frequently found in the head, neck, shoulders, extremities,
and lower back. Trigger points are developed as a result of
muscle injury. This can be acute trauma caused by sport injury, accident, or chronic muscle
overuse brought by repetitive occupational activities, emotional stress or poor posture.
A trigger point is composed of many contraction knots where individual muscle fibers contract
and cannot relax. These fibers make the muscle shorter and constitute a taut band — a group
of tense muscle fibers extending from the trigger point to muscle attachment. The sustained
contraction of muscle sarcomeres compresses local blood supply, resulting in energy shortage
of the area. This metabolic crisis activates pain receptors, generating a regional pain
pattern that follows a specific nerve passage. The pain patterns are therefore consistent
and are well documented for various muscles. Treatment of myofascial pain syndrome aims
to release trigger points and return the affected muscle to original length and strength. Common
treatment options include: – Manual therapy, such as massage, involves
application of certain amount of pressure to release trigger points. The outcome of
manual therapy strongly depends on the skill level of the therapist.
– The Spray and Stretch technique makes use of a vapor coolant to quickly decrease skin
temperature while passively stretching the target muscle. A sudden drop in skin temperature
provides a pain relief effect, allowing the muscle to fully stretch, and thus releasing
the trigger points. – Trigger point injections with saline, local
anesthetics or steroids are well accepted as effective treatments for myofascial trigger
points. – Dry needling — insertion of a needle without
injecting any solution – is reported to be as effective as injections.