Qualitative ultrasonography scale of the intensity of local twitch response during dry needling and its association with modified joint range of motion: a cross-sectional study

Abstract

Background The relevance of local twitch response (LTR) during dry needling technique (DNT) is controversial, and it is questioned whether LTR is necessary for successful outcomes. Furthermore, because the LTR during the deep DNT may be evoked with different intensities, it is unknown whether the magnitude of LTR intensity is associated with optimal clinical results, especially concerning to the effects of joint maximal range of motion (ROM). This study aimed to (i) determine whether visual inspections can quantify the LTR intensity during the DNT through a qualitative ultrasonography scale of LTR intensity (US-LTR scale), and (ii) assess the differences of US-LTR scale associated with changes in the maximal joint ROM. Methods Using a cross-sectional design, seven asymptomatic individuals were treated with DNT in the latent myofascial trigger point in both medial gastrocnemius muscles. During DNT, three consecutive LTRs were collected. The US-LTR scale was used to classify the LTRs into strong, medium, and weak intensities. The categories of US-LTR were differentiated by the velocity of LTRs using the optical flow algorithm. ROM changes in ankle dorsiflexion and knee extension were assessed before and immediately after DNT. Results The US-LTR scale showed the third LTR was significantly smaller than the first one (p < 0.05). A significant difference in velocity was observed between US-LTR categories (p < 0.001). A significant difference in the ROM was observed between the strong and weak-medium intensity (p < 0.05). Conclusions The present findings suggest that the LTR intensity can be assessed using a qualitative US-LTR scale, and the effects of DNT on joint maximal ROM is maximized with higher LTR intensity. This study reports a novel qualitative method for LTR analysis with potential applications in research and clinical settings. However, further research is needed to achieve a broader application.

Dry needling on latent and active myofascial trigger points versus oral diclofenac in patients with knee osteoarthritis: a randomized controlled trial

“…The observed changes in joint ROM could be associated with a relaxation of the MTrPs [ 68 ]. The reason might be that TrPS can change the structure of the muscle by increasing the stiffness in muscle cells and tissues, and the dry needling can release the contracture nodule of the trigger points, thus decreasing resistance when stretching the muscle [ 69 , 70 ].…”

No Evidence of Short-Term Changes in Muscle Activity Elicited by Dry Needling in Chronic Unilateral Shoulder Pain Patients

“…The presence of the LTR during the intervention has been linked to improvement in certain outcomes, such as the range of motion. 14 However, this is not a general rule, since decreased stiffness has been observed in the gastrocnemius and erector spinae muscles following dry needling, but these results have not been reported for the infraspinatus muscle. 57 Recent reviews associate LTRs with a decrease on pain intensity immediately after the intervention, with no significant effects on disability or pressure pain sensitivity.…”

“…12 Other clinical consequences of MTrPs are stiffness, weakness, and limited joint range of motion. 13,14 Furthermore, these symptoms alter the coordination and activation patterns of the muscles involved in shoulder movements. 6,15 One treatment that targets MTrPs is dry needling, which consists in repeated stimulation of MTrPs using a thin needle for a short period of time.…”

“…Furthermore, the compression of MTrP is associated with the presence of clinical pain and referred pain (or, more generally, referred sensations), and it can also produce symptoms reported by shoulder pain patients, such as altered motor and autonomic responses 12 . Other clinical consequences of MTrPs are stiffness, weakness, and limited joint range of motion 13,14 . Furthermore, these symptoms alter the coordination and activation patterns of the muscles involved in shoulder movements 6,15 …”

Ultrasound Confirmation of the Multiple Loci Hypothesis of the Myofascial Trigger Point and the Diagnostic Importance of Specificity in the Elicitation of the Local Twitch Response

“…In the following years, advancements in the technology of the ultrasound probe and computerized imaging processing have resulted in dramatic advancements in image quality [ 29 , 30 ]. In fact, a recent study used US imaging for assessing the intensity of the LTR during the application of dry needling [ 31 ]; however, this study failed to visualize the TrP area itself under US.…”