Analysis of parameters for epidural spinal cord stimulation. 2. Usage ranges resulting from 3,000 combinations

A computerized statistical analysis of 3,000 implanted electrode (multi-contact, quadripolar) combinations for epidural spinal cord stimulation therapy for the management of pain was carried out in three groups: spinal levels (20 different levels, C2-L2), spinal placement (midline and lateral) and contact separation (unipolar, bipolar with a separation of 10, 20 and 30 mm) to investigate the clinically required usage ranges (difference between the perception threshold and tolerance threshold). The usage range is relatively higher at midthoracic levels (T4-T10), and for the combinations located in midline. As the contact separation increases, the usage range increases in bipolar combinations. The usage range of unipolar combinations is higher than that of bipolar combinations with 10 and 20 mm separation, and is less than that of bipolar combinations having a separation of 30 mm.