Effect of Training to Hold Paretic Lower Limb on an Unstable Surface on the Lower Extremity Motor Control in Patients with Hemiplegia: A Randomised Controlled Trial

Introduction: Activities on unstable surfaces provoke greater muscle contractions than those on stable surfaces. The literature suggests that the effort to hold the paretic extremity on an unstable surface could stimulate muscle contractions in patients with hemiplegia. In the present study, we tested the effect of training to hold the hemiparetic lower limb over an unstable surface on contractions of selected muscles in the lower extremity of patients in the early subacute phase of stroke. Aim: To investigate the effect of training to hold the paretic lower limb on an unstable surface on motor control in the lower extremity of patients with hemiplegia in early subacute phase of stroke. Materials and Methods: The study is a randomised control trial. Subjects were recruited from an acute stroke care centre affiliated with a university teaching hospital. First-time ischaemic stroke patients admitted to the acute stroke care center were enrolled in the study. Patients who could follow commands and had a Brunnstrom stage 2 or below in the lower extremity were included. A total of 78 patients were screened, and 56 patients were included in the study. Patients were randomised into two groups. The control group received conventional physiotherapy, while the experimental group was asked to maintain their paretic lower extremity on an unstable surface, such as a Swiss ball, as part of their training, in addition to conventional physiotherapy. Surface Electromyography (SEMG) was recorded from the paretic hip abductor, tensor fascia lata and quadriceps femoris before and after 10 sessions of training. Student's t-test was used to assess the findings, with significance set at p-value <= 0.05. Results: The mean age of participants in the control group was 65.53 +/- 8.19 years, while the mean age of participants in the experimental group was 57.96 +/- 10.89 years. A total of 28 participants in the control group and 28 participants in the experimental group completed the training. Both groups showed an increase in activity in the tensor fascia lata, gluteus medius and quadriceps femoris muscles after 10 sessions of training. Furthermore, the electromyographic activity in all the tested muscles was higher in the experimental group compared to the control group and the difference was statistically significant (p-value <0.01). Conclusion: Training that involves sustaining the paretic lower extremity on an unstable surface, such as a Swiss ball, provoked muscle activity in the paretic lower extremity. Such training can be utilised to improve motor control in the early subacute phase of stroke, where training with minimal movements will be easier for the patient to perform.