Trigger points

TRIGGER POINTS FOR PHYSICAL THERAPY

1. Trigger points Electrotherapy Aditya johan . r,m.fIS

2. definition A Trigger Point ( TrPt ) is a hyperirritable spot associated within a taut band of a skeletal muscle Painful on compression or muscle contraction Usually responds with a referred pain pattern distant from the spot Very often there are nodules palpable within the muscle often at the size of 2-10 mm

3. Etiology & epidemiology Mainly due to overload An injury sustained by a fall Lack of exercise or a bad posture can lead to trigger points Most common in sedentary persons between 27,5-55 years 45% of the patients are men Trigger points may be at different places in both skeletal muscles in the hip, neck, shoulder usually in places where nerves connected the muscle fibers

4. Taut band & nodules

5. Pathophysiological processes Sensitization of peripheral muscle nociceptors Sensitization of second-order neurons in the dorsal horn Dysregulation of the descending endogenous pain control system

6. Characteristics/clinical presentation Active TrPts Active TrPts produce pain symptoms at rest often with referred pain which may be described as radiating or spreading, usually not associated with a nerve or dermatome Latent TrPts Latent TrPts do not provoke spontaneous pain The TrPt may refer pain with direct mechanical stimulation or muscle contraction

7. Electrotherapy for endogenous opiate liberation Endogenous refers to something from within or that is developed from internal systems Opiates are drugs containing opium or its derivatives and are used in medicine for inducing sleep and relieving pain Endogenous Opiate : the ability of the body to produce and release strong pain-relieving substances

8. Endorphins include enkephalins , dynorphin , and β- endorphin The transmission of nociceptive information can be inhibited by pain matrix activity Brainstem areas that provide intrinsic antinociception form a neuronal descending system Rostral ventromedial medulla Periaqueductal gray (PAG) in the midbrain Locus coeruleus in the pons

9. Electrotherapy for endogenous opiate liberation Theoretically, stimulation of the endogenous opiate system can also lead to pain relief Lower frequency stimulation (less than 10 Hz) with longer pulsedurations producing longer lasting relief Electrical stimulators capable of rates of 1 to 5 pps , a pulse duration greater than 200 microseconds An intensity to create a muscle twitch may generate pain relief through this mechanism Electrode placement sites may include motor points that may also be acupuncture points or trigger points.