Short-TermChangesinNeckPain,WidespreadPressurePainSensitivity,andCervicalRangeofMotionAftertheApplicationofTriggerPointDryNeedlinginPatientsWithAcuteMechanicalNeckPain:ARandomizedClinicalTrial

Mechanical neck pain is a common condition that causes substantial disability and economic burden. While various treatments exist, evidence for soft tissue interventions remains limited. Trigger points (TrPs) are hypersensitive regions in taut muscle bands that may contribute to neck pain through peripheral and central sensitization mechanisms. Trigger point dry needling (TrPDN) has shown effectiveness for chronic upper-quarter myofascial pain, but its effects in acute mechanical neck pain were unknown.

The researchers hypothesized that TrPDN could reduce nociceptive inputs early in the injury process, potentially preventing the development of central sensitization and promoting faster recovery.

The investigators conducted a randomized clinical trial with 17 patients (53% female, mean age 25 years) who had acute mechanical neck pain of less than 7 days duration and active trigger points in the upper trapezius muscle. Participants were randomly assigned to either a single session of TrPDN (n=9) or a control group with no intervention (n=8). The TrPDN group received treatment using 0.3 × 30-mm stainless-steel needles inserted into active trigger points until the first local twitch response was obtained, followed by 25-30 seconds of fast-in and fast-out needling at approximately 1 Hz. Outcomes were assessed at baseline, 10 minutes post-treatment, and 1 week later by an assessor blinded to group allocation.

Primary outcomes included neck pain intensity (0-10 numeric rating scale) and pressure pain thresholds (PPTs) measured with an electronic algometer over the C5-6 zygapophyseal joint, second metacarpal, and tibialis anterior muscle. Secondary outcomes included active cervical range of motion measured with a CROM device.

Patients treated with TrPDN experienced significantly greater reductions in neck pain than controls at both 10 minutes (mean change -1.9 vs 0.2, between-group difference 2.1, P<.01) and 1 week (mean change -3.7 vs -0.7, between-group difference 3.0, P<.01). Standardized mean differences were 2.05 at 10 minutes and 3.11 at 1 week, indicating large effect sizes. For pressure pain thresholds, significant group-by-time interactions were found for all tested locations (C5-6 joint: F=12.302, P<.001; second metacarpal: F=7.563, P=.010; tibialis anterior: F=7.604, P=.009). PPT increases were bilateral and ranged from medium to large effect sizes (SMD 0.56-3.01).

For cervical range of motion, significant group-by-time interactions were found for all directions (flexion: F=7.797, P=.008; extension: F=7.294, P=.010; lateral flexion: F=9.031, P=.004; rotation: F=7.674, P=.009), with large between-group differences (SMD 1.34-2.92). Eight of 9 patients (88%) in the TrPDN group experienced post-needling soreness resolving within 24-36 hours, but no increase in pain.

This study provides evidence that a single session of trigger point dry needling can produce meaningful short-term improvements in pain, widespread pressure sensitivity, and movement for patients with acute mechanical neck pain. The effects were not only local but also widespread, suggesting both segmental and central antinociceptive mechanisms. The clinically relevant changes in pain exceeded the minimal clinically important difference of 2.1 points at 1 week, and PPT changes surpassed previously established minimal detectable change values. For clinicians, this suggests TrPDN may be a valuable early intervention to consider alongside other treatments for acute neck pain, potentially helping to prevent progression to chronic pain and central sensitization.

However, the small sample size, single-center design, lack of sham control, and short follow-up limit generalizability. Patients should be informed about temporary post-needling soreness as an expected side effect. Future research with larger samples, multiple treatment sessions, and longer follow-up periods is needed to confirm these promising findings and establish optimal treatment protocols.