The study is designed to evaluate the safety and efficacy of using the L300 Plus as a neuroprosthesis device for walking in patients following an UMN injury or disease. The clinical study is proposed to determine the anticipated adverse event rate and treatment outcomes at the conclusion of the study.

This is a prospective, one-center, single group, repeated measures, non inferiority study. Forty-five (45) subjects suffering from foot drop and thigh muscles weakness due to upper motor neuron injury or disease will be evaluated for this study. Each subject will be in the study for six weeks. Clinical benefits will be measured through an assessment of the gait performance. In particular it will test the hypothesis that the NESS L300 Plus System which involves foot drop correction with thigh muscles activation, may achieve walking enhancements not inferior to those gained from using a system that only corrects foot drop (i.e. NESS L300).

Inclusion Criteria:

• Upper motor neuron lesion
• Thigh muscle weakness - hamstrings or quadriceps strength of less than 4/5 according to manual muscle testing
• Foot drop - toe drag during walking
• Lower limb spasticity - 0-4 according to the modified Ashworth scale
• Responsible mental state, able to follow multiple step directions
• Between 18 and 80 years old
• Available for participation in the study
• Able to understand and sign the informed consent form
• Able to walk independently or with an assistance device (e.g. cane, walker etc.) / spot guarding for at least 10 meters
• Sufficient response to electrical stimulation (visible muscle contractions in a seated or prone position of each designated muscle separately)

Exclusion Criteria:

• Subjects with a demand-type cardiac pacemaker, defibrillator or any electrical or metallic implant
• Cancerous lesion of lower limb, present or suspected
• Medical condition that prevents participation or would likely lead to inability to comply with the protocol [e.g.: congestive heart failure, patient receiving chemotherapy, uncontrolled epilepsy, etc]
• Severe cognitive impairment (MMSE<21)
• Severe neglect (Star cancellation test<30)
• Skin lesion at the site of the stimulation electrodes
• Change in bone-joint structures of the lower limb, such as contractures or deformations; fracture or dislocation, which would be adversely affected by motion from the stimulation
• Pregnancy
• Diagnosis of major depression or psychotic disorder
• Participation in another investigation that may directly or indirectly affect the study results
• Unable to tolerate electrical stimulation