Deep Versus Superficial Dry Needling for Neck Pain: A Systematic Review of Randomised Clinical Trials

This systematic review addresses a critical clinical question in myofascial pain management: whether deep dry needling (penetrating into the muscle to target trigger points) is more effective than superficial dry needling (needling just beneath the skin surface) for treating neck pain associated with myofascial trigger points. While both techniques are commonly used by physical therapists and other clinicians, the comparative evidence has been limited and contradictory. This matters because trigger points in the upper trapezius muscle affect up to 65% of people with upper back pain, and choosing the most effective needling approach could significantly impact patient outcomes while minimizing unnecessary discomfort from deeper needle insertion.

The researchers conducted a comprehensive systematic review following established PRISMA guidelines, searching seven major databases from inception through September 2024. They included only randomized controlled trials that directly compared deep versus superficial dry needling in adults with neck pain and upper trapezius trigger points, focusing on pain intensity and functional disability as primary outcomes. Eight studies met their criteria, involving 525 total participants. The reviewers used rigorous methodology to assess study quality using the Cochrane Risk of Bias 2 tool and performed a best-evidence synthesis rather than meta-analysis due to significant variability in treatment protocols, outcome measures, and follow-up periods across studies.

The analysis revealed that both deep and superficial dry needling provided meaningful short-term improvements in pain and functional disability, but there were no clinically significant differences between the two approaches in most studies. Pain reductions measured on visual analog scales showed improvements of 2.2-2.64 points for deep needling and 1.8-2.36 points for superficial needling in well-designed studies. Only two studies with methodological concerns suggested superior effects for deep needling, with pain reductions exceeding established minimal clinically important differences. Regarding study quality, only two of the eight trials had low risk of bias, four had some concerns, and two had high risk of bias, primarily due to randomization issues and potential measurement bias.

The intervention protocols varied considerably: deep needling used 25-50mm needles inserted 8-10 times or kept in place for 5-15 minutes, while superficial needling used 5-15mm depth with similar techniques.

For patients with neck pain and trigger points, these findings suggest that both deep and superficial dry needling can provide meaningful short-term pain relief and functional improvement. Clinicians may choose either approach based on patient preference, comfort level, and clinical judgment, rather than feeling compelled to use the potentially more uncomfortable deep needling technique. However, several important limitations must be considered: most studies only assessed short-term effects (immediately to 4 weeks), the quality of evidence was mixed, and treatment protocols varied significantly between studies. The lack of long-term follow-up data is particularly concerning for chronic neck pain management, where sustained improvement is crucial.

For clinical practice, the authors recommend standardized protocols: 25-50mm needles for deep needling and 5-15mm depth for superficial needling, both with 8-10 rapid in-and-out movements. However, more high-quality research is needed to establish optimal treatment parameters and confirm long-term effectiveness.