A range of therapeutic options is now available for clinicians managing these patients. After failing conservative treatment alternatives such as behavioural modification and pharmaceutical management, intravesical Botulium toxine injection, sacral neuromodulation (SNM) and percutaneous tibial nerve stimulation (PTNS) are well-established third-line treatment options. SNM and PTNS, have not seen any significant improvement of the devices over the last decade or since FDA approval in 1997. In this study a new,  battery-free implantable tined lead, device (StimRouter™  by Bioness)  is evaluated in a multi-centre study  is evaluated.

From June 2019, seven consecutive patients with urgency incontinence underwent a procedure under local anaesthesia in which a battery-free tined lead electrode (StimRouter™ - Bioness) was implanted on the medial side of the ankle (Figure 1). The Tined lead electrode was implanted by the same surgeon in all cases through a single 5 mm incision, approximately 6 cm proximal to the medial malleolus. After electrical stimulation the appropriate response (flexion of the first toe and paraesthesia of the foot) was looked. After identifying he correct position, the tined lead electrode was in inserted  through a Seldinger technique and after a final electrical check of the appropriate responses, subcutaneously  tunnelled  for  ca 10 cm in the proximal direction of the medial side of the ankle.  The wound was closed with a single absorbable Monocryl suture. The total procedure time was 15-25 minutes. Patients were advised to stimulate their tibial nerve at home for an hour per day .

A total of 7 patients with urgency incontinence and detrusor overactivity were implanted. Five patients had a follow up time of more than 5 months. All five patients reported an improvement in the urgency and incontinence episodes and a significant reduction of incontinence-pad use after treatment. In addition, both day-time as well as night-time frequency was reduced in all implanted patients. (Figure1)

The StimRouter is already an effective therapeutic treatment to help reduce or eliminate chronic pain of a peripheral nerve origin for patients seeking to return to normal, daily activities and can now extend its benefits to patients with OAB. The StimRouter procedure requires only one small incision and is completed in about 30 minutes while the patient is awake under local anesthesia. A hand-held remote allows patients to control their symptoms by delivering gentle stimulating pulses to the Tibial Nerve to reduce the chronic urge to urinate. Our multicentre data presented here are the first follow up data on feasibility and effect of the  battery-free implantable tibial nerve stimulation device (Stimrouter) for the treatment of urinary incontinence. There were no adverse events and all implanted patients reported a significant improvement in urgency and incontinence episodes as well as pad use and day-time and night-time frequency.

We can conclude that tibial nerve stimulation with Stimrouter could be a very promising therapy for patients with refractory idiopathic OAB.