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 MEASURES: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 pressure threshold (PPT) was used to measure nocioceptive sensitivity. The percent change in muscle thickness from rest to contraction was calculated to represent muscle function. Participants were dichotomized and compared based on whether or not they experienced at least one twitch response on the most painful side and spinal level during dry needling.RESULTS:Participants experiencing local twitch response during dry needling exhibited greater immediate improvement in lumbar multifidus muscle 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, and there 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 successful treatment.

Background: Little is known about the physiologic mechanism of dry needling. While some evidence suggests that dry needling may decrease nocioceptive sensitivity and facilitate muscle function, no studies to date have examined these physiologic changes compared to clinical outcomes.Objective: To examine changes in lumbar multifidus (LM) muscle function and nociceptive sensitivity after dry needling in patients with LBP and to determine if such changes differ in patients that exhibit improved disability (responders) and those that do not (non-responders).Design: Quasi-experimental study.Methods: Sixty-six volunteers with mechanical LBP (38 men, age = 41.3 +/- 9.2 years) completed the study. Ultrasound measurements and pain algometry of the LM were taken at baseline and repeated immediately following dry needling treatment to the LM muscles and after one week. The percent change in muscle thickness from rest to contraction was calculated for each time point to represent muscle function. Pressure pain threshold (PPT) was used to measure nociceptive sensitivity. Participants were dichotomized as responders and non-responders based on whether or not they experienced clinical improvement using the modified Oswestry Disability Index after one week. 2 x 3 mixed-model ANOVA were conducted for group (responders vs. non-responders) by time.Results: Patient responders exhibited larger improvements in LM muscle contraction and nociceptive sensitivity 1 week, but not immediately, after dry needling than non-responders.Conclusions: Our results suggest that there may be lasting and clinically relevant sensorimotor changes that occur in LBP patients that improve with dry needling treatment that partially explain the physiologic mechanism of action. Published by Elsevier Ltd.

STUDY DESIGN:Quasi-experimental.OBJECTIVES:To explore for associations between demographic, patient history, and physical examination variables and short-term improvement in self-reported disability following dry needling therapy performed on individuals with low back pain (LBP).BACKGROUND:Dry needling is an intervention used with increasing frequency in patients with LBP; however, the characteristics of patients who are most likely to respond are not known.METHODS:Seventy-two volunteers with mechanical LBP participated in the study. Potential prognostic factors were collected from baseline questionnaires, patient history, and physical examination tests. Treatment consisted of dry needling to the lumbar multifidus muscles bilaterally, administered during a single treatment session. Improvement was based on percent change on the Oswestry Disability Index at 1 week. The univariate and multivariate associations between 33 potential prognostic factors and improved disability were assessed with correlation coefficients and multivariate linear regression.RESULTS:Increased LBP with the multifidus lift test (rpb = 0.31, P = .01) or during passive hip flexion performed with the patient supine (rpb = 0.23, P = .06), as well as positive beliefs about acupuncture/dry needling (rho = 0.22, P = .07), demonstrated univariate associations with Oswestry Disability Index improvement. Aggravation of LBP with standing (rpb = -0.27, P = .03), presence of leg pain (rpb = -0.29, P = .02), and any perception of hypermobility in the lumbar spine (rpb = -0.21, P = .09) were associated with less improvement. The multivariate model identified 2 predictors of improved disability with dry needling: pain with the multifidus lift test and no aggravation with standing (R(2) = 0.16, P = .01).CONCLUSION:Increased LBP with the multifidus lift test was the strongest predictor of improved disability after dry needling, suggesting that the finding of pain during muscle contraction should be studied in future dry needling studies.LEVEL OF EVIDENCE:Prognosis, level 1b.

The patient was a 22-year-old man who was currently serving in a military special operations training program. He was referred to a physical therapist for a chief complaint of left elbow pain that currently prevented him from performing routine upper extremity exercise activities. Due to the traumatic nature of the patient's injury, inability to fully extend his elbow, and palpation findings, there was concern for a radial head fracture. Therefore, the physical therapist ordered radiographs of the left elbow, which revealed an intra-articular fracture involving the radial head that extended through the neck of the radius.