Objective: To investigate the relationship between dry needling-induced twitch response and change in pain, disability, nociceptive sensitivity,and lumbar multifidus muscle function, in patients with low back pain (LBP).
Design: Quasi-experimental study.Setting Department of Defense Academic Institution.
Participants: Sixty-six patients with mechanical LBP (38 men, 28 women, age: 41.3 [9.2] years).
Interventions: Dry needling treatment to the lumbar multifidus muscles between L3 and L5 bilaterally.
Main outcome measure:s Examination procedures included numeric pain rating, the Modified Oswestry Disability Index, pressure algometry,and real-time ultrasound imaging assessment of lumbar multifidus muscle function before and after dry needling treatment. Pain pressurethreshold (PPT) was used to measure nocioceptive sensitivity. The percent change in muscle thickness from rest to contraction was calculatedto represent muscle function. Participants were dichotomized and compared based on whether or not they experienced at least one twitchresponse on the most painful side and spinal level during dry needling.
Result:s Participants experiencing local twitch response during dry needling exhibited greater immediate improvement in lumbar multifidusmuscle function than participants who did not experience a twitch (thickness change with twitch: 12.4 [6]%, thickness change without twitch:5.7 [11]%, mean difference adjusted for baseline value, 95%CI: 4.4 [1 to 8]%). However, this difference was not present after 1-week, andthere were no between-groups differences in disability, pain intensity, or nociceptive sensitivity.
Conclusions: The twitch response during dry needling might be clinically relevant, but should not be considered necessary for successfultreatment.
To pop, or not to pop? That has long been a questions among clinicians who utilize spinal manipulation. Is the cavitation, or audible pop, necessary to achieve a “successful” manipluation? While some literature indicates that it may not be necessary, this remains a viable question.
In an almost synonymous fashion, achieving a local twitch response (LTR) has been viewed by some as one of the primary goals with dry needling as it has been associated with better treatment outcomes (1,2). The local twitch response has been shown to be associated with a decrease in nociceptive and inflammatory chemicals (1,3-6), increased blood flow (7), and decrease pain (8) to name a few. In some circles, the LTR considered as the hallmark of a successful dry needling treatment. Recently, the authors sought to investigate the association between the LTR and changes in pain and function in patients with lumbar pain.

**Abstract of the week shared by NAIOMT Clinical Fellowship Instructor Gary Kearns, PT, COMT, FAAOMPT
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