Effect of Using a Bionic Leg on Physiological and Biomechanical Measures in Stroke Patients

The Acute Effect of Using a Bionic Leg on Physiological Cost Index and Biomechanical Measures in Chronic Stroke Patients

This study will assess the effect of wearing a wearable bionic leg, on the physiological cost index and biomechanical measures in patients with stroke. Patients will be tested during a range of activities (sit-to-stand, walking) with and without the Bionic Leg, and following a 30-min training program.

The aim of this study is to investigate the acute effect of wearing a Bionic Leg on:

1. The Physiological Cost Index (PCI) and Biomechanical measures (gait, postural sway) of stroke patients compared to when they do not wear a Bionic Leg.
2. Whether after wearing a Bionic Leg for 30-minutes during a training session influences the Physiological Cost Index (PCI) and any Biomechanical measures (gait, postural sway) of stroke patients

Individuals who volunteer to participate in the present study will be asked to engage in 4 sessions in the laboratory. Firstly, participants will be asked to take part in two familiarisation sessions, which will be delivered on two separate occasions. These sessions will last one-hour each and will allow participants (stroke patients) to become accustomed to wearing and using the Bionic Leg. Sessions will consist of sit to stand, walking and stairs exercises, which will allow individuals to become familiarised with the Bionic Leg device. They will then be asked to complete 6x 10m walks to identify their self-selected walking pace. In session 3, individuals will be randomly assigned to either use the Bionic Leg, or not. Participants will initially be asked to stay seated and rested for 5 minutes so a resting heart rate can be taken. If participants are assigned to the Bionic Leg condition first, they will conduct all the following tests with the Bionic leg on, however, if not, they will perform all the tests without wearing the Bionic Leg. They will then partake in a 3-minute walk test, which will include walking at their self-selected pace (found in session 1) for 3 minutes. Following this a 15-minute rest period will be taken, and 3 x timed-up and go tests will be conducted (see outcome measures). Next, participants will be asked to take part in a balance test, and then a 6-minute walk test (see outcome measures). Following a 15-minute rest, participants will complete 10 x sit-to-stands.

During the testing session where participants are not wearing the Bionic Leg, once they have finished all of the above testing, participants will engage in further testing during this session. Following a 15-minute recovery period participants will take -part in a 30-minute training session whilst wearing the Bionic Leg. The training programme will ask participants to engage in a variety of walking, balance and stair exercises. Following this, individuals will be given a further 15-min rest period, and the original tests (PCI, TUG, postural sway, 6-min walk, sit-to-stand) which were detailed above, would be re-assessed. These tests will be undertaken whilst not wearing the Bionic Leg. It is anticipated that this session will last approximately 2 hours.

Inclusion Criteria:

• Patients with a diagnosis of stroke within 3 months to 5 years of study start date.
• Community patients who are medically stable and are either (1) currently receiving physical therapy from a neurophysiotherapy practice or (2) attending a community-based stroke support group and do not actively receive physical therapy.
• Individuals who are able to stand and step with an aid or assistance
• Patients who are cognitively aware to undertake rehabilitation exercises, physical therapy and activity.
• Patients whose height is 1.58-1.92m
• Patients whose weight is less than 159kg.

Exclusion Criteria:

• Unresolved deep-vein thrombosis
• Unstable cardiovascular conditions
• Open wounds
• Active drug resistant infections
• Recent fractures of involved limb
• Peripheral arterial disease
• Incontinence
• Severe osteoporosis
• Non-weight bearing