PPTNS: The Urgent PC Neuromodulation System® (Uroplasty, Minnetonka, MN, USA) was used. Subjects underwent one 30-min session 2 days per week for 8 consecutive weeks in an outpatient clinic. Patients were placed in the supine position without anesthesia. PPTNS was delivered using a needle electrode that was inserted 3-4cm cephalad and 2 cm posterior to the medial malleolus at a 60º angle towards the ankle joint to a depth of approximately 0.5-1cm. Successful placement was confirmed by the presence of electric sensation 5 cm above and below the insertion site or a digital plantar flexion. PPTNS was undertaken at the highest amplification (0-20 mA) at a frequency of 20 Hz, causing neither a motor response nor pain.