title: The effects of anodal transcranial direct current stimulation and patterned electrical stimulation on spinal inhibitory interneurons and motor function in patients with spinal cord injury.
abstract: Supraspinal excitability and sensory input may play an important role for the modulation of spinal inhibitory interneurons and functional recovery among patients with incomplete spinal cord injury (SCI). Here, we investigated the effects of anodal transcranial direct current stimulation (tDCS) combined with patterned electrical stimulation (PES) on spinal inhibitory interneurons in patients with chronic incomplete SCI and in healthy individuals. Eleven patients with incomplete SCI and ten healthy adults participated in a single-masked, sham-controlled crossover study. PES involved stimulating the common peroneal nerve with a train of ten 100 Hz pulses every 2 s for 20 min. Anodal tDCS (1 mA) was simultaneously applied to the primary motor cortex that controls the tibialis anterior muscle. We measured reciprocal inhibition and presynaptic inhibition of a soleus H-reflex by stimulating the common peroneal nerve prior to tibial nerve stimulation, which elicits the H-reflex. The inhibition was assessed before, immediately after, 10 min after and 20 min after the stimulation. Compared with baseline, simultaneous application of anodal tDCS with PES significantly increased changes in disynaptic reciprocal inhibition and long-latency presynaptic inhibition in both healthy and SCI groups for at least 20 min after the stimulation (all, p < 0.001). In patients with incomplete SCI, anodal tDCS with PES significantly increased the number of ankle movements in 10 s at 20 min after the stimulation (p = 0.004). In conclusion, anodal tDCS combined with PES could induce spinal plasticity and improve ankle movement in patients with incomplete SCI.
authors.affiliation: Department of Rehabilitation Medicine, Keio University School of Medicine, Shinjuku-ku, Tokyo, Japan.
authors.forename: Tomofumi
authors.initials: T
authors.lastname: Yamaguchi
authors.affiliation: Department of Rehabilitation Medicine, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa, 259-1193, Japan. tofuji@xc5.so-net.ne.jp.
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Fujiwara
authors.affiliation: Center for Neural Regeneration, Taipei Veterans General Hospital, Taipei, Taiwan, ROC.|National Yang Ming University, Taipei, Taiwan, ROC.
authors.forename: Yun-An
authors.initials: YA
authors.lastname: Tsai
authors.affiliation: Center for Neural Regeneration, Taipei Veterans General Hospital, Taipei, Taiwan, ROC.
authors.forename: Shuen-Chang
authors.initials: SC
authors.lastname: Tang
authors.affiliation: Department of Rehabilitation Medicine, Keio University School of Medicine, Shinjuku-ku, Tokyo, Japan.
authors.forename: Michiyuki
authors.initials: M
authors.lastname: Kawakami
authors.affiliation: Department of Rehabilitation Medicine, Keio University School of Medicine, Shinjuku-ku, Tokyo, Japan.
authors.forename: Katsuhiro
authors.initials: K
authors.lastname: Mizuno
authors.affiliation: Department of Rehabilitation Medicine, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa, 259-1193, Japan.
authors.forename: Mitsuhiko
authors.initials: M
authors.lastname: Kodama
authors.affiliation: Department of Rehabilitation Medicine, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa, 259-1193, Japan.
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Masakado
authors.affiliation: Department of Rehabilitation Medicine, Keio University School of Medicine, Shinjuku-ku, Tokyo, Japan.
authors.forename: Meigen
authors.initials: M
authors.lastname: Liu
mesh_terms: D000328:Adult; D000842:Ankle / Q000502:physiology*; D006181:H-Reflex / Q000502:physiology*; D006801:Humans; D007395:Interneurons / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D009044:Motor Cortex / Q000502:physiology*; D009433:Neural Inhibition / Q000502:physiology*; D009473:Neuronal Plasticity / Q000502:physiology*; D010543:Peroneal Nerve / Q000502:physiology* / Q000503:physiopathology; D013119:Spinal Cord Injuries / Q000534:rehabilitation*; D065908:Transcranial Direct Current Stimulation / Q000379:methods*; D004561:Transcutaneous Electric Nerve Stimulation / Q000379:methods*
keywords: Disynaptic reciprocal inhibition; H-reflex; Locomotion; Presynaptic inhibition; Rehabilitation; Spinal plasticity