Background
Spinal cord injury (SCI) commonly impairs proprioception and tactile sensation which significantly affects the walking ability of SCI patients together with decreased muscle strength. Restoration of sensory function is as important as a recovery of muscle strength in regaining the walking ability for SCI patients. Robot-assisted gait training (RAGT) is an alternative treatment method of conventional overground gait training or body weight-supported treadmill training for SCI patients. RAGT can provide repetitive, interactive, intensive, and task-specific practice which may help improve walking ability by accelerating neuroplastic processes. Robots utilized for RAGT can be divided into two mechanical structural categories; exoskeleton and end-effector type. The end-effector type robots use footplates to generate motion of the lower limb and provides somatosensory inputs repetitively and regularly which can simulate balance training through feedback control. But, previous studies of RAGT on SCI patients only utilized exoskeletal type robots, except for 1 case study and 1 feasibility study. Therefore, the purpose of this case study is to show the effects of RAGT using end-effector type robots on SCI patients with impaired proprioception but preserved muscle strength.
Case report
A 76-year-old patient was hospitalized at our hospital for back pain. The patient was damaged to the dorsal column of the spinal cord during neurosurgery. After the injury, proprioception was impaired, but pinprick and light touch were intact. He was an L2 paraplegic patient with American Spinal Injury Association Impairment Scale D. At the time of transfer to our department, the patient presented fair grade in Lt. hip flexor muscle (L2) and good grade in all the other key muscle groups of the lower limbs in manual muscle tests. However, the proprioception tests conducted at the patient's ankle joint and IP joint of great toe were assessed at 1/1, 0/0, respectively. The patient was evaluated to 8 level of Walking Index for Spinal Cord Injury (WISCI-II), which requires a walker and physical assistance for ambulation (Figure 1). After the patient was received a total of 19 sessions RAGT using Morning WalkⓇ, the proprioception tests conducted at the patient's ankle point showed improvement at 2/2 (Table 1). Accordingly, the patient was able to ambulate independently with a walker (Figure 2). The scores of WISCI-II, Berg Balance Scale (BBS), and mobility part of Spinal Cord Independence Measure (SCIM)-II were increased after the end-effector type RAGT (Table 2).
Conclusion
In SCI patients with reduced proprioception, the end-effector type RAGT using Morning walkⓇ may improve proprioception and their functional level about walking ability. Therefore, it would be beneficial to actively conduct end-effector type RAGT for SCI patients with reduced proprioception, and further research will be needed in the future. |
