Objectives The objective of this study was to assess the short-term effects of dry needling on spasticity, gait, and muscle architecture of patients with chronic stroke. Methods A case series study was designed; and six chronic stroke patients with ankle spasticity and gait impairment received a single session of dry needling for gastrocnemius medialis, lateralis, and soleus muscles. The main outcome measures were the Modified Modified Ashworth Scale (MMAS), and Timed Up and Go test (TUG). In addition, ultrasonography measurements (e.g. thickness, pennation angle, and fascicle length) were performed for gastrocnemius medialis at baseline (T0), immediately after intervention (T1) and 30 min after intervention (T2), while the MMAS and TUG Test were only measured at T0 and T2. Results Based on the TUG test, there was a significant improvement in gait function (p = 0.023). Furthermore, the MMAS results (p = 0.014) showed a decrease in resistance to passive movements from plantar flexor muscles. Furthermore, a significant decrease in pennation angle (p = 0.014) and muscle thickness (p = 0.001), and also a significant increase in fascicle length of gastrocnemius medialis (p = 0.001) were observed after dry needling. Discussion & conclusions Based on the outcomes of this study, dry needling application seems to have short term effects in terms of reducing spasticity, improving gait, and muscle architecture of gastrocnemius medialis in patients with chronic stroke. The changes of muscle architecture may be interpreted as the positive effects of dry needling on the physical properties of hypertonic muscles.
Keywords: Dry needling; muscle architecture; spasticity; ultrasound imaging.