Table 1 Cervical spinal cord stimulation data
| Author & Article | N | Avg Age | Avg PD duration | Indication for SCS | DBS | Lead Location | Frequency; pulse width | Follow up period |
Pain Scale Pre ➔ Post | Gait | UPDRS—III (Motor Exam) | Additional Comments |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Thevathasan et al. 2010 | 2 | 76 ± 1.4 | NA | Advanced PD | No | C2 | 130 Hz–300 Hz; 240–200 μsec | 10 days |
VAS Subthreshold P = 0.35 Suprathreshold P = 0.04 |
10 m walk P = 0.72 | P = 0.44 | Patients stimulated at two frequencies during with- and without- paresthesia conditions which was adjusted by increasing the amplitude of stimulation. Frequency for patient one was 130 Hz, which was chosen due to its use in DBS; frequency for patient two was 300 Hz, which was chosen due to animal studies. Measurements were done > 20 min after switching stimulation conditions, a time frame chosen based on subthalamic stimulation. No difference was found in function. The authors postulated that the lack of effect may have been due to type of stimulation as the animal model previous showed result with 30–60s intermittent bursts. Criticisms also fell on location of electrodes which were thoracic in the animal model. |
| Hassan et al. 2013 | 1 | 43 | 8 | Neck and upper extremity pain | No | C2 | 40 Hz; 500 μsec | 24 months |
VAS 8 or 9 ➔ 0–2 |
10 m walk PostOp- 17 s 1 year - NA 2 year - 11 s |
Post Op − 28 1 year - 22 2 year - 16 | Patient did well with medical management for 4 years until symptoms worsened; SCS implant resulted in improved pain and PD motor symptoms. When trial leads were removed, pain returned immediately while PD symptoms gradually returned gradually in 2 days. Remarkably, after permanent implant at year two of follow-up, patient demonstrated improved motor scores compared to year one, although it may be possible that improvement in function lead to improved physical conditioning. Subjectively, she noted improved tremor and rigidity. |
| Mazzone et al. 2019 | 6 | 71 ± 7.3 | 17.1 ± 6.1 | Back pain, vascular pain | No | C2–3 |
Tonic (135–185 Hz, 60–210 μsec) | 12 months |
VAS Improved (P < 0.05) |
Gait speed P < 0.05 Cadence P < 0.05 Step length P < 0.05 Stride length P > 0.05 |
Tonic P < 0.05 | The primary indication for SCS was for pain in the tonic stimulation group and for parkinsonian motor symptoms in the Burst group. The Burst group patient population were those who were deemed unsuitable for DBS except for 3 patients whose symptoms were refractory to DBS. The authors found that a longer latency was needed prior to seeing benefits of motor changes in tonic stimulation as UPDRS-III scores were not significantly different in the acute post-SCS phase but was different in the 3, 6, and 12 months follow up data. A slight decrease of effectiveness for pain and motor control was observed 12 months after SCS implantation for both waveforms, but burst waveform showed attenuated decrease. At the end of the 12 month study, L-dopa dose was reduced up for both groups (Tonic 1333.3 ± 471.9 mg to 1083.3 ± 2640 mg per day; Burst 835.0 ± 310.1 mg to 730 ± 273.7 mg). The study was funded by University grants and no industry sponsorship was indicated. |
| 12 | 65.5 ± 11.1 | 11.1 ± 5.3 | PD or atypical parkinsonism | DBS in 3 cases | C2–3 | Burst (250–500 Hz on; 40 Hz off, 1000 μsec) | 12 months |
VAS Improved (P < 0.05) |
Gait speed P < 0.05 Cadence P < 0.05 Step length P < 0.05 Stride length P < 0.05 |
Burst P < 0.001 |