Have you ever been to a manual therapist, such as a chiropractor, physiotherapist, or massage therapist, and when pressure was applied to a muscle you experienced pain in another area of your body? If so, you may have experienced referred pain from a trigger point. A trigger point is a local hyperirritable point which is found within a tight band of muscle, and when compressed, refers pain in a recognizable pattern to another area of the body (see below for common examples).1,2

Types of Trigger Points

Trigger points can be classified into two categories: active and latent.1,2,3 Active trigger points cause pain during everyday activites, and when they are compressed, pain spreads or radiates in a distribution consistent with the pain complaint.1,2,3 Active trigger points are often accompanied by reduced ranges of motion, without joint swelling or reproducible neurological deficits.1 Latent trigger points by comparison do not cause pain at rest, but produce muscle weakness and referral of pain when compressed.1,2,3 The only current reliable form of diagnosis is palpation on clinical examination.2

What Causes Trigger Points?

Although there is no definitive cause for trigger points, there are many theories that are agreed upon in the literature, including acute and repetitive trauma.1 The most common contributing factor I have seen in clinic is repetitive occupational duties, such as prolonged sitting in poor postures and repetitive lifting.  Other common contributing factors include stress, repetitive sports injuries, lack of exercise, sleep disturbance, and joint problems, all of which can result in microtrauma to muscles.1 Essentially, any muscle that is frequently under high tension or stress can be predisposed to developing trigger points.1 At the cellular level, these areas have increased inflammatory markers and elevated spontaneous neurological activity.3

What Should I Do About Trigger Points?

There are many different treatment options to consider to relieve the pain associated with trigger points. The first line of defence is removing the perpetuating factor that is causing the stress of microtrauma on muscles.1,2 This can be done by modifying work stations and increasing movement throughout the day. The second stage of treatment includes reducing the muscular tension. This can be done through hands-on treatment with a chiropractor or massage therapist,1,2 including stretching and ischemic compression.2 Other alternatives include exercise,2 acupuncture,1 heat/ice application,1 electrostimulation,1 dry needling,1,2 medication,1 and local injections.1,3

 

1-supraspinatus-muscle

Supraspinatus muscle2

2-infraspinatus-muscle

Infraspinatus muscle2

3-infraspinatus-muscle-2Infraspinatus muscle2 4-subscapularis-muscle

Subscapularis muscle2

References

  1. Trigger points: Diagnosis and Management
  2. Treatment of myofascial trigger point in patients with chronic shoulder pain: RCT
  3. Myofascial trigger points and innervation zone locations in upper trapezius muscles