A method for determining a change in position of a neurostimulation lead relative to a stimulation target tissue of a patient is provided. The method comprises implanting a first proximity sensor on a surface of the patient, implanting a second proximity sensor on the surface of the patient, measuring a change in a distance between the first and second proximity sensors, and inferring the change in position of the lead relative to the stimulation target tissue from the measured change in distance. The method further comprises inferring an increase in a distance between the lead and the stimulation target tissue when the distance between the first and second proximity sensors increases. The method also comprises conveying electrical stimulation energy to therapeutically stimulate the stimulation target tissue, and modulating a stimulation parameter in response to the measured change in distance.