Patient-friendly summary
If you read nothing else
Bottom line
Trigger point injections may reduce acute myofascial pain more than medical management alone, but the conclusion rests on only four small trials with notable heterogeneity and bias concerns.
Preliminary evidencePublished
Evidence hierarchy
Study participants
Adults aged 18 or older with acute myofascial pain, in trials from Turkey, Korea, and the USA
Full research — for clinicians and curious readers
Study Summary
This systematic review and meta-analysis pooled four randomized controlled trials (1,151 records screened) to compare trigger point injections against medical management alone for acute myofascial pain. The pooled analysis found that trigger point injections significantly reduced pain scores relative to medical treatment (standardized mean difference -2.09; 95% CI -3.34 to -0.85; P = 0.001). The authors describe this as the first systematic review and meta-analysis on this specific question and note the result favors trigger point injections for acute myofascial pain. They caution that substantial heterogeneity, varying risk of bias across the included studies, limited geographic representation, and possible publication bias limit how broadly the findings can be generalized.
Key Findings
| Finding | Detail | Impact |
|---|---|---|
| Trigger point injections significantly reduced acute myofascial pain versus medical management | Across four pooled RCTs, the standardized mean difference was -2.09 (95% CI -3.34 to -0.85, P = 0.001), with a negative SMD indicating greater pain reduction in the injection group. | High |
| Only four RCTs met inclusion criteria from 1,151 screened records | After removing 159 duplicates and excluding studies during title/abstract and full-text screening, four randomized controlled trials (conducted in Turkey, Korea, and the USA) qualified for both the systematic review and meta-analysis. | Medium |
| Individual trials consistently favored trigger point injections | Kocak et al. (2019) found TPI superior to intravenous NSAIDs; Suh et al. (2014) found a significant drop in VAS scores with ultrasound-guided TPI versus oral NSAIDs; Farrow et al. (2022) reported greater pain reduction and lower rescue-therapy rates in the emergency department; Yanuck et al. (2020) reported high patient satisfaction. | Medium |
| Heterogeneity and variable risk of bias temper the conclusions | The authors report heterogeneity in pain scores and in the medications used during injection that could not be resolved, plus risk-of-bias ratings ranging from low (Yanuck 2020) to some concerns (Kocak 2019, Suh 2014) to high (Farrow 2022). | High |
Strengths
- Described as the first systematic review and meta-analysis directly comparing trigger point injections with medical management for acute myofascial pain
- Followed PRISMA and Cochrane Handbook methodology with a four-database search (PubMed, Scopus, Web of Science, Cochrane Library)
- Used explicit, predefined inclusion and exclusion criteria with two independent reviewers for screening and risk-of-bias assessment
- Restricted to randomized controlled trials and formally assessed bias with the ROB-2 tool
Limitations
- Only four RCTs met inclusion criteria, and the total pooled sample size is not reported
- Substantial heterogeneity in pain scores and in medications used during injection could not be resolved, limiting generalizability
- Risk of bias varied, with one trial rated high risk and two rated as having some concerns
- Limited geographic representation (Turkey, Korea, USA) and potential for publication bias
- Restricted to English-language publications, and lack of standardized dosing protocols across trials
Key Takeaways for Patients
What This Means for You
For short-term (acute) muscle pain caused by trigger points, injections into the trigger point reduced pain more than medication alone in this analysis.
The conclusion is based on only four small trials with differences in how they were run, so the findings are promising but not definitive.
Trigger point injections are described as a minimally invasive procedure that can generally be done safely with minimal side effects.
Talk with a qualified clinician about whether a trigger point injection is appropriate for your situation, since this evidence comes from a small number of studies.