Effects of Powered Hip Flexion Device in Persons With Multiple Sclerosis

Individuals with multiple sclerosis (MS) frequently experience problems with walking that may include difficulty with advancing the leg during the swing phase of gait which can lead to a loss of independence and a higher risk of falls. To improve walking ability in this population, devices such as ankle-foot orthoses (AFO) and functional electrical stimulation (FES) are commonly used. However, recent advances in technology and robotics have led to the development of affordable and commercially available battery powered exoskeletons marketed towards improving activities such as hiking, running and cycling. There is emerging but limited evidence that hip flexion-assisting devices can modify kinematics and muscle activity during gait in people with MS, with several small-scale studies showing tolerability and shifts toward more normal hip motion during walking. However, there are no studies on the use of new commercially available powered hip flexion assist devices. Therefore, the purpose of this case series is to assess the immediate effects on walking ability of a commercially available, non-FDA regulated, powered hip flexion assist device (Hypershell X, Shenzhen, China).

Inclusion criteria

• Age 18-80
• Diagnosis of relapsing remitting, primary progressive or secondary progressive MS
• Unilateral or bilateral hip flexion weakness (Manual muscle testing score of 3 or less)
• Ability to walk at least 30 meters without requiring rest and without physical support or assistance from another person.
• Waist circumference 26-48", Height 5 '- 6'2", Weight 100-230lbs

Exclusion criteria

• Prior regular use of a hip flexion orthosis within the past 6 months.
• Cognitive or communication deficits that would limit ability to participate safely.
• Significant pain or deformity of the lower extremities that could impact walking ability.
• Severe spasticity (Modified Ashworth Score of 3 or 4) of the hips or lower extremities that could impact walking ability.
• Any other neurological conditions that may affect gait.