Prospective randomized feasibility study comparing manual vs. automatic position-adaptive spinal cord stimulation...

The majority of patients experience uncomfortable stimulation associated with posture changes, especially when lying down. The spinal cord moves within the intrathecal space in response to positional changes affecting the size of the stimulated area accordingly and causing overstimulation or understimulation. To accommodate for positional changes, patients have to manually adjust the stimulation parameters; therefore, an automatic position-adaptive SCS was designed to address these issues. The primary objective of this study was to establish the extent of position-related variations in SCS stimulation parameters experienced by chronic pain patients implanted with surgical, laminectomy-type leads under both automatic and manual SCS conditions.

A total of 18 patients completed a single-center, prospective, non-blinded, randomized (1:1), feasibility clinical study with a two-arm crossover design. All patients undergoing SCS treatment for chronic refractory back and or leg pain associated with failed back surgery, post-laminectomy, or radicular pain syndromes that were refractory to conservative and surgical interventions were eligible for enrollment. After the manual stimulation mode, the patients were randomized to one of two study arms: manual or automatic position-adaptive stimulation and then crossed over to a different arm. All patients were followed for a total of 5 months (± 2 weeks).

Analysis indicated statistically significant differences between therapeutic and threshold stimulation intensity for the supine position compared with all other body positions when using either automatic position-adaptive stimulation or manual stimulation, except for threshold amplitudes in the prone position for automatic stimulation.

Similar variations were reported for manual and automatic stimulation intensity in response to positional changes.