Trigger Point

Trigger Points are central to Myofascial Pain Syndrome
Trigger Points result in generalized muscle changes
1. Tense skeletal muscle bands
2. Muscle shortening
3. Muscle Weakness
4. Decreased muscle range of motion
Trigger Point compression induces local and referred pain
1. Compression of Trigger Point leads to local ischemia
2. Ischemia leads to local inflammatory factor (prostaglandin, kinin) release

See Trigger Point Locations
Taut, ropy bands, knots or Nodules of muscle fibers
1. Surrounded by normal feeling muscle
Muscle tenderness to palpation
1. Local twitch response to palpation ("jump sign")
2. Involuntary shortening of fibrous muscle band
Trigger Points occur in predictable locations
1. Trigger Points occur longitudinally along muscle axis
2. Trigger Points are consistent from patient to patient
3. Axial muscles (Posture) most commonly affected
Pain Radiation
1. Dull, aching, deep pain on Trigger Point palpation
2. Predictable referred pain to distal reference zones
Functional Disability
1. Decreased range of motion
2. Decreased flexibility on active and passive stretch
3. Weakness of affected muscle
Trigger Point pain types
1. Active Trigger Point
  1. Ongoing, persistent pain
  2. May activate satellite or secondary Trigger Points
2. Latent Trigger Point
  1. Asymptomatic until palpated