Table 2.
Comparative studies between conventional/tonic & High Frequency (10 khz) SCS.
| Study | Indication | Study Design | Methods | Outcome Measures | Results | Conclusion |
|---|---|---|---|---|---|---|
| Kapural et al. [26] | Chronic Intractable back and leg pain | Randomized controlled trial | 198 subjects with back and leg pain, randomized in 1:1 ratio to HF SCS (>10 khz) or conventional SCS. Of these 171 passed trial and received permanent implant. | 10 outcome—≥50% pain relief in the back | At 3 months, In HF group 84.5% were responders for back pain (vs. 43.8% for tonic SCS) and 83.1% were responders for leg pain (vs. 55.5% for tonic SCS); (p < 0.001). Superiority of HF stimulation was sustained through a 12-month period. |
HF stimulation was better than tonic stimulation for treatment of chronic intractable back and leg pain. |
| Kapural et al. [31] | Chronic Intractable back and leg pain | Randomized controlled trial | 198 subjects with back and leg pain, randomized in 1:1 ratio to HF SCS (>10 khz) or conventional SCS. Of these 171 passed the trial and received permanent implant. | 10 outcome—≥50% pain relief in the back | At 24-months follow up, more subjects continued to be responders to HF stimulation than conventional SCS (back pain-76.5% vs. 49.3%, leg pain-72.9% vs. 49.3%; p < 0.001). Also back and leg pain decreased to a greater degree with HF stimulation than tonic SCS (p < 0.001). |
HF (10 khz) stimulation was better than tonic stimulation for treatment of chronic intractable back and leg pain. |
| Amirdelfan et al. [32] | Chronic Intractable back and leg pain | Randomized controlled trial | 198 subjects with back and leg pain, randomized in 1:1 ratio to HF SCS (>10 khz) or conventional SCS. Of these 171 passed the trial and received permanent implant. QOL and functional measures were collected up to 12 months. | ODI, GAF, CGIC, PSQI, SF-MPQ-2 | At 12 months follow up; ODI-69.6% subjects were classified into lower disability category with HF (vs. 55.1% with tonic SCS; p = 0.01). Subjects had a more significant improvement in GAF scores in HF group vs. tonic SCS (14 vs. 6.5, respectively; p < 0.01). Significant improvements were seen in continuous, intermittent, and neuropathic pain in HF group vs. tonic SCS on the SF-MPQ-2 scale. However, no difference was observed on the affective disorders subscale. Significant improvements were also seen in the HF group on CGIC and PSQ1 scales compared to tonic SCS. |
High frequency (10 khz) stimulation was better than tonic stimulation in improving quality of life and functional outcomes in patients with chronic intractable back and leg pain. |
SCS—Spinal Cord Stimulation, High frequency—HF, ODI—Oswestry disability index, GAF—Global assessment of functioning, CGIC—Clinical global impression of change, PSQI—Pittsburgh sleep quality index, SF-MPQ—Short-form Mcgill pain questionnaire, QOL—Quality of life.