Table 2.
Baseline demographics and characteristics of the study subjects (mITT population).
| Characteristics | DTM SCS (N = 51) | Conv-SCS (N = 54) | p-value* |
|---|---|---|---|
| Sex N (%) | .695 | ||
| Female / male | 29 (56.9%) / 22 (43.1%) | 33 (61.1%) / 21 (38.9%) | |
| Age (y) | .183 | ||
| Mean ± SD | 62.9 ± 13.5 | 59.6 ± 12.1 | |
| BMI (kg/m2) | .525 | ||
| Mean ± SD | 30.2 ± 4.5 | 30.9 ± 6.1 | |
| Years with pain N (%) | .902 | ||
| Mean ± SD | 9.5 ± 8.0 | 9.4 ± 8.4 | |
| Baseline back pain (VAS) (cm) | .857 | ||
| Mean ± SD | 7.9 ± 1.0 | 8.0 ± 1.1 | |
| Leg pain n (%)(%)† | N = 45 | N = 45 | 1.000 |
| Unilateral | 14 (31.1%) | 15 (33.3%) | |
| Bilateral | 31 (68.9%) | 30 (66.7%) | |
| Baseline leg pain (VAS) (cm)† | N = 45 | N = 45 | .009 |
| Mean ± SD | 6.7 ± 2.4 | 7.8 ± 1.6 | |
| Pain diagnosis | |||
| Chronic intractable back pain | 51 (100.0%) | 54 (100.0%) | N/A |
| Chronic intractable leg pain | 45 (88.2%) | 45 (83.3%) | .581 |
| Pain etiology | |||
| Neuropathic pain | 51 (100.0%) | 54 (100.0%) | N/A |
| Radiculopathy | 45 (88.2%) | 46 (85.2%) | .777 |
| Degenerative disc disease | 38 (74.5%) | 42 (77.8%) | .819 |
| Spondylosis | 35 (68.6%) | 40 (74.1%) | .666 |
| Mild/moderate spinal stenosis | 27 (52.9%) | 19 (35.2%) | .079 |
| Lumbar facet-mediated pain | 15 (29.4%) | 13 (24.1%) | .660 |
| Sacroiliac dysfunction | 9 (17.6%) | 6 (11.1%) | .409 |
| Internal disc disruption/annular tear | 8 (15.7%) | 7 (13.0%) | .784 |
| Spondylolisthesis | 5 (9.8%) | 5 (9.3%) | 1.000 |
| Other chronic pain | 22 (43.1%) | 29 (53.7%) | .331 |
⁎
p-values for continuous data were calculated from two sample t-test. p-values for categorical data were calculated from Fisher's Exact test.
†
Subjects with leg pain at baseline. Subgroup analysis was performed on baseline leg pain and there was no statistical evidence of a differential treatment effect for the significant difference at baseline.