Trigger point injections (TPI)

Are TPI safe and effective in the management of chronic non-malignant pain 3 months’ duration?

What is known
Evidence indicates that TPI:

• plus intra-articular injection of sodium hyaluronate may be safe and effective for treating knee pain caused by osteoarthritis;
  
• when performed as a sole treatment, may be effective in relieving the symptoms of chronic head, neck, and shoulder pain, whiplash syndrome, and cervicogenic headache;
  
• simple injectants such as saline and sterile water are safer than botox and are equally effective;
  
• with lidocaine in combination with neck stretching exercises is as effective as combined ultra sound therapy/neck stretching, both of which are more effective than neck stretching alone for treating chronic head, neck, and shoulder pain.
  

What we don’t know

• Is there a dose response to TPI, and if so, what is the minimum dose/intensity required to achieve a clinically significant treatment effect?
  
• Does the type or volume of fluid injected affect treatment outcomes?
  
• Is there a difference in treatment effect between specific wet needling of the trigger point and non-specific injection of fluid into the region surrounding the trigger point?
  
• Does the needling action, the injection solution, or both, contribute to the treatment effect?
  
• How strong is the placebo effect in TPI therapy?
  

Recommendation
A short trial (three sessions of TPI) is worth trying in focal chronic pain of the neck, head and shoulders in a patient who can be relied upon to do stretching exercises.

Reference
Scott A, Guo B. Trigger point injections for non-malignant chronic pain. Edmonton, AB: Alberta Heritage Foundation for Medical Research (HTA 34). Available from URL: http://www.ahfmr.ab.ca/publications.html, August 2004.