Long-term tonic spinal cord stimulation in advanced Parkinson's disease: No effect from stimulation under placebo-controlled evaluation.

•Chronic spinal cord stimulation effectiveness was evaluated in four PD patients.•Double blinded cross over evaluation was performed using subthreshold stimulation.•An open label evaluation with regular suprathreshold stimulation was also performed.•No statistically significant effect was produced with either stimulation.•This study highlights the lack of strong clinical evidence supporting SCS for PD.