Up to 40 to 50% of individuals who survive stroke experience physical disability. The ability to stand up from sitting is an important functional activity, a prerequisite for upright mobility and an important factor for independent mobility. However, sit-to-stand (STS) is biomechanically demanding and requires higher lower extremity joint torques than walking or stair climbing. Recently, robotic devices have been used in neurorehabilitation to facilitate treatment efficacy. The Tibion Bionic leg is a mobile, intention-based robotic device designed to allow individuals post-stroke to perform activities more normally. Results to date have shown improvements in balance, gait and functional performance in individuals post-stroke following therapeutic intervention using the Tibion Bionic Leg (TBL). Here we studied the effects of actuated limb assistance on hemiparetic limb asymmetry during STS using unilateral and bilateral vertical ground reaction forces (vGRF). We hypothesized that
The Tibion Bionic Leg is a mobile, wearable, intentionbased robotic limb orthosis (Tibion Pk-100 Bionic Leg, Tibion Corporation, Sunnyvale, CA) developed as a therapeutic device. The device is actuated to supply force to assist or resist leg extension and flexion providing limb assistance against gravity during extension (as in sit-to-stand or free standing) and controlled flexion (as in stand-to-sit). Force sensors placed under the foot detect a threshold force and trigger the actuation. In its primary mode (AUTO) the device clearly activates to assist the motion of the wearer. Three settings can be adjusted to individualize participant assistance or therapeutic challenge: threshold (force criterion required to activate the device), assistance (amount of assistance provided as percentage of body weight) and resistance (resistance provided during controlled flexion as in stand-to-sit or stair descent)the actuated limb assistance provided to the paretic side by the TBL would promote more symmetrical movement and force production by individuals post-stroke.
The study suggests that the Tibion allows the user to involve their weaker leg more than would otherwise be possible, enabling greater weight bearing through the involved lower extremity. When used during therapy, it may enhance the capability of the wearer to perform activities with more appropriate biomechanics. Repetition of appropriate movement patterns with greater engagement of the paretic limb may ensure functional improvements.
Byl (2012) concuded in here case series that additive clinical-functional benefits may be achieved by incorporating mobile, intention-based robotic technology into therapist-supervised mobility training for patients in the late-phase post stroke.