Subjective outcome following neurostimulator implantation as drop foot therapy due to lesions in the central nervous system-midterm results.

BACKGROUND: Drop foot can be caused by many conditions. Stroke is one of the major causes of drop foot and 5% of stroke survivors suffer from hemiplegia, which in some cases, can manifest as drop foot. The abnormal gait resulting from the lack of innervation of the extensor muscles may result in a secondary malposition of the foot and lead to a steppage gait. Among the several therapy options for the treatment of drop foot, functional electrostimulation (FES) with a transcutaneous peroneal nerve stimulator (tPNS) or an implantable peroneal nerve stimulator (iPNS) represents the two recent approaches. OBJECTIVE: Although therapy with an iPNS has been proven to be effective, a subjective patient assessment has not yet been executed. The aim of this study was to assess the patient's satisfaction with the therapy by using two established surveys. METHODS: The Rivermead Mobility Index (RMI) and the Reintegration to Normal Life Index (RNLI) were used for this retrospective study. The RMI includes 15 questions which are to be answered as either "yes" or "no" and given a value of 1 or 0, respectively, with a maximum of 15 points possible. The RNLI includes 11 questions which are to be answered with the use of a visual analog scale (VAS, 0 to 10 cm). In this case, a maximum adjusted score of 100 points is possible. RESULTS: The total study cohort involved 56 patients treated with an iPNS. Thirty-five complete data sets for the RMI and 29 for the RNLI could be achieved. A significant difference in the total score of both surveys was observed between the deactivated and the activated iPNS (RMI: p = 0.02; RNL: p = 0.01). CONCLUSION: A significant improvement in patient satisfaction was detected with the use of an activated iPNS after a mean time span of 4 years. Due to the marked mobility, an increase in the social satisfaction and integration could be achieved. Both aspects represent essential components for the recovery and quality of life of the patients.

[Foot drop treatment by implantation of a neuroprosthesis (ActiGait®)]. / Behandlung des Fallfußes durch Implantation einer Neuroprothese (ActiGait®).

OBJECTIVE: Gait improvement by restoring dorsiflexion using a neuroprosthesis implant. INDICATIONS: Foot drop with damage to the 1st motor neuron; passive mobility in ankle is possible; adult patients. CONTRAINDICATIONS: Foot drop with peripheral damage and injury to the peroneal nerve; already implanted stimulators (e.g., defibrillator, pacemaker, or pain stimulator); severe anesthesia risks in multimorbid patients. SURGICAL TECHNIQUE: Surgery in lateral position. Searching for the peroneal nerve after dorsal incision in the popliteal fossa, using the medial edge of the biceps femoris as anatomic landmark. After identification of the motor branch of the peroneal nerve by positive dorsiflexion after using electrostimulation apply the electrode cuff on the nerve. Epifascial implantation of stimulation body lateral at the middle third of the thigh over the tractus iliotibialis. POSTOPERATIVE MANAGEMENT: Pain-adapted full weight bearing, no knee flexion more than 90° for 4-6 weeks, activation of neuroprosthesis 3 weeks after surgery, physiotherapy with gait training is required. RESULTS: Between 2013 and 2015, implantation of the neuroprosthesis was performed in 21 patients (13 men/8 women) with chronic foot drop due to a central lesion. Significant improvement in walking speed measured with the 10 meter walk test (11.8 ± 5.4 s to 7.9 s ± 3.4; p = 0.007), in gait endurance with 6 min walk test (212.2 ± 75.5 m to 306.4 ± 96.4 m; p ≤ 0.001), and in gait performance using the Emory Functional Ambulation Profile (105.9 ± 49.7 s to 63.2 ± 31. 3 s; p ≤ 0.001). No patient required surgical revision. Postoperative bleeding was recorded in one case (4%). Patient satisfaction and improvement in mobility and quality of life could be achieved (95% and 90%, respectively).

[Functional electrostimulation for drop foot treatment : Clinical outcome]. / Funktionelle Elektrostimulation zur Therapie des neurogenen Fallfußes : Klinisches Outcome.

INTRODUCTION: Neurologic paralysis of the foot due to damage to the central nervous system is primarily caused by a cerebral insult. The ankle-foot orthosis (AFO), which is the classical conservative treatment option, is associated with drawbacks, e.g., increased contractures, limited mobilization from the sitting position, and cosmetic aspects. METHODS: Functional external electrostimulation (FES) is an suitable treatment method for patients with a central lesion and intact peroneal nerve. Based on this method, the neuroprosthesis is a dynamic therapy option in the form of an implantable nerve stimulator (ActiGait® system, Otto Bock, Duderstadt, Germany) which is placed directly on the motor branch of the peroneus nerve and results in active foot lifting. The aim of the present study is to evaluate the clinical effect of the ActiGait® system with regard to its suitability for everyday use by means of gait tests with an emphasis on time-distance parameters and to compare it with the current literature. RESULTS AND CONCLUSION: In this retrospective study, the clinical results after implantation of the ActiGait® system are presented and evaluated. In summary, the implantation of a neuroprosthesis in patients with stroke-related drop foot represents a sensible and promising therapy option.