Robotic resistance treadmill training improves locomotor function in human spinal cord injury: a pilot study

Wu M, Landry JM, Schmit BD, Hornby TG, Yen S-C. Robotic resistance treadmill training improves locomotor function in human spinal cord injury: a pilot study.ObjectiveTo determine whether cable-driven robotic resistance treadmill training can improve locomotor function in humans with incomplete spinal cord injury (SCI).DesignRepeated assessment of the same patients with crossover design.SettingResearch units of rehabilitation hospitals in Chicago.ParticipantsPatients with chronic incomplete SCI (N=10) were recruited to participate in this study.InterventionsSubjects were randomly assigned to 1 of 2 groups. One group received 4 weeks of assistance training followed by 4 weeks of resistance training, while the other group received 4 weeks of resistance training followed by 4 weeks of assistance training. Locomotor training was provided by using a cable-driven robotic locomotor training system, which is highly backdrivable and compliant, allowing patients the freedom to voluntarily move their legs in a natural gait pattern during body weight supported treadmill training (BWSTT), while providing controlled assistance/resistance forces to the leg during the swing phase of gait.Main Outcome MeasuresPrimary outcome measures were evaluated for each participant before training and after 4 and 8 weeks of training. Primary measures were self-selected and fast overground walking velocity and 6-minute walking distance. Secondary measures included clinical assessments of balance, muscle tone, and strength.ResultsA significant improvement in walking speed and balance in humans with SCI was observed after robotic treadmill training using the cable-driven robotic locomotor trainer. There was no significant difference in walking functional gains after resistance versus assistance training, although resistance training was more effective for higher functioning patients.ConclusionsCable-driven robotic resistance training may be used as an adjunct to BWSTT for improving overground walking function in humans with incomplete SCI, particularly for those patients with relatively high function.