Post-needling soreness after myofascial trigger point dry needling: Current status and future research

This review examines post-needling soreness, a common complication of treating myofascial trigger points with dry needling. The authors analyzed the current state of knowledge about this condition and proposed directions for future research in the field. Myofascial trigger points are hypersensitive nodules in taut bands of skeletal muscle, present in various painful conditions such as tension-type headache, migraine, temporomandibular disorders, shoulder pain, and lateral epicondylalgia. Dry needling has been recommended as effective treatment for relieving trigger point–related pain.

Post-needling soreness is considered a consequence of neuromuscular damage and the hemorrhagic and inflammatory reaction generated by the needle. This pain is described as a constant pressure or dull ache, easily distinguishable from the sharp, restrictive pain experienced before treatment. Analysis of the literature showed that post-needling soreness is very common after deep dry needling, ranging from 50% to 100% of cases, and usually lasting less than 72 hours. Mean maximum intensity was reported between 3.5 and 5.6 points on a 0–10 scale.

Factors such as the number of needle insertions, perceived pain during the procedure, psychosocial factors, and sex influence the perception of post-needling soreness. Precise trigger point localization and adequate hemostasis can minimize this complication. The authors emphasize that the clinical relevance of post-needling soreness remains uncertain. Although most patients do not consider this pain particularly distressing compared with the original myofascial pain, patients with elevated levels of post-needling soreness, who do not perceive treatment efficacy at the first session, or who do not have high myofascial pain intensity before treatment may be more likely to consider post-needling soreness distressing and functionally limiting and may drop out of treatment.

Research shows that 51% of patients who received lidocaine injections at trigger points were reluctant to undergo subsequent procedures because of post-injection pain. Several adjuvant therapies have been investigated to reduce post-needling soreness, including percutaneous electrical nerve stimulation, low-load exercise, ultrasound, spray and stretch, and ischemic compression, showing promising results. The authors emphasize that post-needling soreness should be considered when evaluating the efficacy of dry needling, since it can mask the original myofascial pain and influence patients' pain assessments, especially in evaluations of immediate or short-term effects. They recommend that post-needling soreness be assessed separately from the original trigger point pain in future studies.

Limitations include the small number of published studies and important differences in study design, making definitive conclusions about frequency, intensity, or mean duration of post-needling soreness impossible. This work provides an important foundation for the development of safer and more effective clinical protocols.