gms | German Medical Science

Objective: Drop-foot is a common problem following ischemic and hemorrhagic stroke, and is associated with an increased risk of falling and increased effort of walking. Thus, drop-foot contributes to reduced mobility and independence. The conventional approach is the use of an orthesis or a surface stimulation system which is, on the long run, inconvenient for the patient. Overall experience with an implanted drop-foot stimulator is still very limited, with 15 reported cases since 1999. The purpose of the present prospective study is to test the safety and efficacy of an implanted drop-foot stimulator.

Methods: 80 patients were screened, and 7 patients were ultimately eligible for implantation. Main exclusion criteria were the inability to walk and/or to perform passive ankle dorsiflexion. All patients underwent walking tests (speed, covered distance in 6 min) and gait analysis prior to surgery, as well as on days 42 and 84 after surgery.

Results: The surgical morbidity was 0%. We observed 1 subcutaneous hematoma accounting for a complication rate of 14%. The walking speed increased from 0.62 to 0.768 (day 42) and 0.772 m/sec (day 84) (p<0.05) and the distance from 210.75 to 260.25 (day 42) (p<0.05) and 248.25 m (day 84). The gait analysis indicated improved initial dorsiflexion, improved but still reduced “push off” in the late standing period and reduced dorsiflexion in the late swing period in all patients.

Conclusions: The implanted drop-foot stimulator in patients with established hemiplegia significantly improved the walking speed and the walking distance and aids in normalizing the gait, which gives back a certain mobility and independency to the disabled patients.