Muscle knot? It might be a trigger point.

About 23 million people, or 10 percent of the U.S. population, have one or more chronic disorders of the musculoskeletal system.1 One of these is myofascial pain syndrome, a common painful muscle disorder caused by myofascial trigger points. Trigger points are discrete, focal, hyperirritable spots located in a taut band of muscle. The spots are painful on compression and can produce referred pain, referred tenderness, and decreased muscle function.

Trigger points are classified as being active or latent. Active trigger points cause pain at rest, are tender to touch, and cause a referred pain pattern.  Latent trigger points do not cause spontaneous pain, but they may restrict movement or cause muscle weakness.2

No one is sure what exactly causes trigger points. Many researchers agree that acute trauma or repetitive microtrauma may lead to the development of a trigger point. Lack of exercise, prolonged poor posture, vitamin deficiencies, sleep disturbances, and joint problems may all predispose a person to the development of micro-trauma. Occupational or recreational activities that produce repetitive stress on a specific muscle or muscle group commonly cause chronic stress in muscle fibers, leading to trigger points.3

Activities that might cause trigger points include holding a telephone receiver between the ear and shoulder to free arms, prolonged bending over a table, sitting in chairs with poor back support, and moving boxes using improper body mechanics. Sports injuries, acute or repetitive, can also lead to the development of trigger points.

Nonmedical treatment of trigger points include home stretching exercises, massage therapy, acupuncture, acupressure, and osteopathic manipulation. Medical management includes prescription pain medicines, muscle relaxers, and various other medicines. A common and highly effective treatment for trigger points involves a "trigger point injection" with lidocaine. The lidocaine has 2 effects on the trigger point: it numbs the area to provide immediate pain relief, and the liquid manually disrupts the muscle knot to break up inflamed fibers. Usually one trigger point treatment is sufficient, but for chronic or severe conditions, multiple injections over several weeks may be necessary.

If you have muscle knots that are not responding to home treatments, call the office for an appointment. After a thorough evaluation, I will determine whether medicines, a trigger point injection, or both will best help the problem.

1. Imamura  ST, Fischer  AA, Imamura  M, Teixeira  MJ, Tchia Yeng  Lin, Kaziyama  HS, et al.  Pain management using myofascial approach when other treatment failed.  Phys Med Rehabil Clin North Am.  1997;8:179–96.
2. Simons DG, Travell JG, Simons LS. Travell & Simons' Myofascial pain and dysfunction: the trigger point manual. 2d ed. Baltimore: Williams & Wilkins, 1999:5.
3. Han  SC, Harrison  P.  Myofascial pain syndrome and trigger-point management.  Reg Anesth.  1997;22:89–101.