Myofascial Pain Syndrome
Myofascial Pain Syndrome or Trigger Points
Myofascial pain syndrome - or trigger points - are the most common cause of undiagnosed or misdiagnosed aches and pains, especially recurrent headaches, neck pain and back pain. What makes trigger points clinically important is their ability to:
- Cause pain
- Refer pain to the head, neck, arms or legs
- Be misdiagnosed as other health problems like sciatica or herniated discs.
What is a Trigger Point?
Trigger points are small, focal, tender spots located in a muscle. The spots are painful on compression and can produce referred pain, tenderness, motor dysfunction, or mimic other health problems like chest pain or sciatica.1
Acute trauma or repetitive microtrauma may cause stress on muscle fibers and the formation of trigger points. Patients may have local, persistent pain resulting in a decreased range of motion in the affected muscles. These include muscles of posture in neck, shoulders, and pelvis. Trigger points may also manifest as tension headache, sciatic pain in the legs, or low back pain.
Lack of exercise, poor posture, poor sleep, and joint problems may all contribute to the development of microtrauma.2 Occupational or recreational activities that produce repetitive stress on a muscle or muscle group cause chronic stress in muscle fibers, leading to trigger points.
Activities including holding a telephone receiver between the ear and shoulder, prolonged bending, sitting in chairs with poor back support, improper height of arm rests or none at all, and moving boxes using improper body mechanics can all help to cause trigger points.3
Patients who have trigger points often report local, persistent pain that usually results in a decreased range of motion of the muscle in question. Often, the muscles used to maintain body posture are affected, namely the muscles in the neck, shoulders, and pelvis.4 Activities including holding a telephone receiver between the ear and shoulder, prolonged bending, sitting in chairs with poor back support, improper height of arm rests or none at all, and moving boxes using improper body mechanics can all help to cause trigger points.3
Clinical Presentation
In the head and neck region, myofascial pain syndrome with trigger points
can manifest as tension headache, ringing in the ears, TMJ pain, eye symptoms, and stiff neck.5In the lower extremities, trigger points may involve pain in the quadriceps and calf muscles and may lead to a limited range of motion in the knee and ankle. Trigger-point hypersensitivity in thebuttock muscles often produces intense pain in the lower back.5
Evaluation
Pressing on a tender muscle or nodule of muscle fiber of harder than normal consistency is the physical finding most often associated with a trigger point.6 Localization of a trigger point is based on the doctor's sense of feel, assisted the patient's pain and by visual and local twitch response.6 Pressing on the muslce will cause pain over the muscle and may cause radiation of pain to the head, arms or legs.
Types of Trigger Points
- An active trigger point is an area of extreme tenderness that usually lies within the skeletal muscle and which is associated with a local or regional pain.
- A latent trigger point is a dormant (inactive) area that has the potential to act like a trigger point.
- A secondary trigger point is a highly irritable spot in a muscle that can become active due to a trigger point and muscular overload in another muscle.
- A satellite myofascial point is a highly irritable spot in a muscle that becomes inactive because the muscle is in the region of another trigger pain.
Treatment of Myofacial Trigger Points
Ischemic Compression
The purpose of ischemic compression is to deliberately increase the blockage of blood to an area so that, upon release, there will be a resurgence of blood. This washes away waste products, supplies necessary oxygen and helps the affected tissue to heal. This increase of blood flow to the area is called a hyperemia.
Following treatment it is important to gently stretch the area to help the muscle regain its full length.
The first treatment should be conservative, lasting one or two minutes, followed by a day of rest. The treatment is resumed on alternate days until the pain abates and full usage is returned, usually within 3 to 10 sessions. Appropriate application of ice following treatment is important to help manage pain and inflamation.
Ultrasound Terapy
Ultrasound is just as effective a treatment as trigger point injections and should be offered as an alternative since it is a less invasive procedure.7 Ultrasound is thought to promote pain relief several ways. It may neutralize pain due to increased circulation in the painful area, or it may cause other changes that result in decreased inflammation.
A recent study of trigger point injections for chronic lower back pain showed that there was no benefit from these injections.8,9
1. Imamura S T, 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. Han SC, Harrison P. Myofascial pain syndrome and trigger-point management. Reg Anesth 1997;22: 89-101.
3. Rachlin ES. Trigger points. In: Rachlin ES, ed. Myofascial pain and fibromyalgia: trigger point management. St. Louis: Mosby, 1994:145-57.
4. Simons DG, Travell JG, Simons LS. Travell & Simons' Myofascial pain and dysfunction: the trigger point manual. 2d ed. Baltimore: Williams & Wilkins, 1999:11-93.
5. Sola AE, Bonica JJ. Myofascial pain syndromes. In: Bonica JJ, ed. The management of pain. 2d ed. Philadelphia: Lea & Febiger, 1990:352-67.
6. Simons DG, Travell JG, Simons LS. Travell & Simons' Myofascial pain and dysfunction: the trigger point manual. 2d ed. Baltimore: Williams & Wilkins, 1999:94-173.
7. Treatment of myofascial trigger-points with ultrasound combined with massage and exercise – a randomised controlled trial. Arne N. Gam, Susan Warming et al. Department of Rheumatology, Bispebjerg Hospital, University of Copenhagen, Lyngholmvej 53, 2720 Vanløse, Denmark, 6 May 1998
8. Injection therapy for subacute and chronic low back pain: an updated Cochrane review. Staal JB, de Bie RA, de Vet HC, Hildebrandt J, Nelemans P. Spine (Phila Pa 1976). 2009 Jan 1;34(1):49-59.
9. Trigger point injections for chronic non-malignant musculoskeletal pain: a systematic review. Scott NA, Guo B, Barton PM, Gerwin RD. Pain Med. 2009 Jan;10(1):54-69. Epub 2008 Nov 5.