Leg Cycling Leads to Improvement of Spasticity by Enhancement of Presynaptic Inhibition in Patients with Cerebral Palsy

Senshu Abe; Yuichiro Yokoi; Naoki Kozuka

doi:10.1298/ptr.E10228

Leg Cycling Leads to Improvement of Spasticity by Enhancement of Presynaptic Inhibition in Patients with Cerebral Palsy

Phys Ther Res. 2023;26(2):65-70. doi: 10.1298/ptr.E10228. Epub 2023 Jun 20.

Authors

Senshu Abe^{1

2}, Yuichiro Yokoi³, Naoki Kozuka⁴

Affiliations

¹ Department of Physical Therapy, Rehabilitation Part, Hokuto Social Medical Corporation, Tokachi Rehabilitation Center, Japan.
² Advanced Rehabilitation Office, Hokuto Social Medical Corporation, Tokachi Rehabilitation Center, Japan.
³ Department of Physical Therapy, Rehabilitation of Healthcare and Science, Hokkaido Bunkyo University, Japan.
⁴ Department of Physical Therapy, School of Health Sciences, Sapporo Medical University, Japan.

Abstract

Objective: The purpose of this study was to investigate if leg cycling could reduce lower extremity spasticity in patients with cerebral palsy (CP). In addition, we investigated whether the intervention could cause changes in the modulation of presynaptic inhibition.

Methods: This study was a quasi-experimental study, with pretest-posttest for 1 group. Participants in this experiment were eight adult patients with CP with lower extremity spasticity. Spasticity parameters assessed were the amplitude of soleus maximum Hoffmann's reflex (H_max) and maximum angular velocity (MAV) of knee flexion measured using the pendulum test. D1 inhibition, which seems to be related to the presynaptic inhibition, was recorded by measuring soleus Hoffmann's reflex (H-reflex) with conditioned electric stimuli to the common peroneal nerve.

Results: D1 inhibition was significantly enhanced immediately by the cycling intervention. The amplitude of the soleus H_max was significantly depressed, and there was significant difference in H_max/maximum M-wave. The MAV was increased due to inhibition of the stretch reflex.

Conclusion: Leg cycling suppressed stretch reflex and H-reflex, and caused plasticity of inhibitory circuits in patients with CP with lower extremity spasticity. These findings strongly suggest that lower extremity spasticity can be improved by cycling movements.

Keywords: Cerebral palsy; Cycling; Pendulum test; Presynaptic inhibition; Spasticity.