Table 1.
Indications and outcomes of conventional SCS.
| Study | Indication | Study Design | Methods | Outcome Measures | Results | Conclusion |
|---|---|---|---|---|---|---|
| Kemler et al. [19] | CRPS | Randomized trial | CRPS patients assigned in a 2:1 ratio to SCS + PT group (n = 36) & PT group (n = 18). 24 of 36 patients underwent permanent implant of SCS device. | VAS, GPE, functional status, health-related quality of life | Intention-to-treat analysis showed significant reductions in pain at 6 m in SCS + PT group (p < 0.001). Improvements in GPE also observed in SCS group. | SCS can reduce pain in carefully selected CRPS patients. |
| Harke et al. [20] | Sympathetically maintained CRPS | Prospective trial | CRPS patients underwent SCS implant, and pain intensity was estimated during SCS free intervals of 45 min every 3 m vs. under treatment. | VAS, pain disability index, reduction in pain medication | Improvements in VAS during treatment vs. SCS free intervals (p < 0.01). Reduction in pain meds during treatment (p < 0.01). | Functional status, quality of life, and pain medication usage can be improved with use of SCS in sympathetically mediated CRPS. |
| North et al. [21] | FBSS | Randomized controlled trial | 50 FBSS patients randomized to SCS and reoperation. If results of randomized treatment unsatisfactory, patient could crossover to alternative. | Self-reported pain relief, patient satisfaction, crossover to alternative procedure | Among 45 patients available for follow up, SCS (9 of 19) was more successful than reoperation (3 of 26 patients) (p < 0.01). (5 of 24 in SCS group) vs. (14 of 26 in reoperation group) crossed over (p = 0.02). | SCS is more effective than reoperation in patients with persistent radicular pain after spine surgery. |
| Kumar et al. [22] | FBSS/Neuropathic limb pain | Multicenter randomized controlled trial | 100 FBSS patients with predominant leg pain of neuropathic radicular origin randomized to SCS + CMM group vs. CMM alone group and followed for 6 m. | 10 outcome—≥50% pain relief in the legs. 20 outcome—improvement in back and leg pain, health-related quality of life, functional capacity, use of pain medications |
In the intention-to-treat analysis at 6m, 48% SCS patients (n = 24) & 9% CMM patients (n = 4) achieved 10 outcome. SCS + CMM group also achieved the 20 outcomes significantly more than the CMM alone group (p < 0.05 for all comparisons). |
SCS is superior to CMM in the treatment of limb pain of neuropathic origin in patients with prior lumbosacral surgery. |
| De vos et al. [23] | PDN | Multicenter randomized controlled trial | 60 PDN patients refractory to conventional medical therapy were randomized in 2:1 ratio to best conventional medical practice (with SCS) or without (control) SCS group and followed at regular intervals. | EuroQoL 5D, SF-MPQ, VAS | At 6m follow up, average VAS decreased from 73 (baseline) to 31 in SCS group (p < 0.001); VAS remained unchanged at 67 in control group (p = 0.97). SF-MPQ and EuroQoL 5D also improved significantly in the SCS group. |
SCS therapy significantly reduced pain and improved quality of life in patients with PDN. |
| Van beek et al. [24] | PDN | Prospective two-center clinical trial | 48 patients with PDN were treated with SCS and followed for 5 years. | NRS score for pain, PGIC, and treatment success (50% reduction of NRS score or significant PGIC) | Patients showed significant improvements in all outcome measures at the follow-up visits. Treatment success was observed in 55% of patients after 5 years, and 80% of patients with permanent implant continued to use their SCS device. |
SCS is successful in alleviating pain in patients with PDN. |
SCS—Spinal Cord Stimulation, VAS—Visual analog scale, GPE—Global perceived effect, PDN—Painful diabetic neuropathy SF-MPQ—Short-form Mcgill pain questionnaire, NRS—Numeric rating scale, PGIC—Patient’s global impression of change, PT—Physical Therapy, EuroQol 5D- EuroQol five dimensions questionnaire.