Efficacy of Cervical Spinal Cord Stimulation for Chronic Pain

Timothy Deer, MD President Elect, INS Center for Pain Relief - Charleston, WV.

This work was supported by St. Jude Medical. Dr. Deer is a paid consultant of St. Jude Medical.

IntroductionScientific evidence has been accumulated that provides

confirmation of spinal cord stimulation (SCS) treatment as an efficacious and cost-effective treatment option that for many disease states, such as lumbar and cervical radiculopathy, FBSS, peripheral neuropathy, ischemic pain and CRPS, should be employed much earlier in the treatment continuum[1-3].

Reimbursement of SCS in the cervical region of the spine has recently been challenged based on supposed lack of clinical literature to support the therapeutic modality.

To refute this assumption, we analyzed data from an international registry to support the appropriateness of use of cervical SCS in chronic pain patients.

MethodsAn IRB-approved, prospective, multicenter, international registry

study was conducted in which patients were enrolled after implantation of an SCS system.

Outcomes were collected at 3, 6, and 12 months post-implantation, and included: direct patient report of percentage of pain relief categorical ratings of pain relief pain-related disability as assessed by the Pain Disability Index (PDI)

questionnaire* categorical ratings of quality of life (QoL) measures categorical ratings of patient satisfaction Patient willingness to undergo the procedure again Patient recommendation of the procedure

*PDI scores were retrospectively collected to reflect patient status at baseline.

ResultsDiagnosis, pain area, and implant information

are provided for 38 patients that received implantation of the SCS lead in the cervical spine.

Follow-up data is provided for 26 patients that have completed the 3 month visit, 21 patients that have completed the 6 month visit, and 16 patients that have completed the 12 month visit.

Patient DiagnosesDiagnosis Number (%) of

PatientsCRPS I or II 9 (23.7%)

Failed Back Surgery Syndrome

9 (23.7%)

Failed Neck Surgery Syndrome

5 (13.2%)

Radiculopathy 4 (10.5%)

Unknown 2 (5.3%)

Other* 9 (23.7%)*Includes cervical DDD (n=2), Neuralgia (n=2), neck axiom neuropathy (n=1), disc displacement (n=1), brachial plexopathy (n=1), and Reynaud’s (n=1).

Implant Information

Lateral undermining or midline laminotomy with caudal to cranial placement

The majority (78.9%) of leads were implanted with the tip at C2 or C3.

Twenty-eight SCS patients (73.7%) were implanted with percutaneous leads and 10 patients (26.3%) received paddle leads.

Results

Direct patient report of percentage of pain relief was 54.2 (+21.4)%, 60.2 (+24.8)% and 66.8 (+22.5)% at 3,6, and 12 months post-implant, respectively.

Results

Pain relief was categorized as Excellent/Good (61.6%) at 3 months with similar results observed at 6 and 12 months. Only one patient reported their pain relief as Poor.

Results

Mean PDI scores were 49.6 (+14.4) at baseline and were significantly reduced to 34.5 (+15.7) at 3 months (p=0.0013), to 33.4 (+15.5) at 6 months (p=0.0014), and to 28.4 (+13.4) at 12 months (p=0.0001). A decrease of 8.5 points or greater is considered clinically significant1.1 Soer R, Reneman MF, Vroomen PC, Stegeman P, Coppes MH. Responsiveness and minimal clinically important change of the Pain

Disability Index in patients with chronic back pain. Spine (Phila Pa 1976) 2012;37(8):711-5.

Results

Overall Quality of life was reported as Improved or Greatly Improved by 73.1% of patients at 3 months. Similar results were reported at 6 and 12 months. Few patients reported that any measure of the QoL was deteriorated at any time point.

Results

At 3 months post-implant, 92.4% of patients indicated they were Very Satisfied or Satisfied with the SCS device. Similar results were noted at 6 and 12 months. No patients indicated they were dissatisfied with the SCS device at 12 months.

Results

At 3 months, patients were asked if they would undergo the procedure again, and 76.9% of them indicated that they would. Results were similar at 6 and 12 months. Few patients indicated that they would not undergo the procedure again.

Results

The percentage of patients that indicated that they would recommend the procedure to others was also 76.9% at 3 months with similar results at 6 and 12 months. Only one patient indicated that they would not recommend the procedure to others.

Summary and ConclusionsSpinal cord stimulation has become a mainstream modality for

treatment of certain specific neuropathic pain conditions as those elucidated in this study.

This provides further supporting evidence that, similar to placing leads in the thoracic spine, the use of SCS in the cervical spine is acceptable, medically necessary and should be reimbursed in the appropriately selected and treated patient.

Furthermore, because spinal cord stimulation has been shown to provide superior pain relief than other treatment modalities, and due to the minimally invasive and reversible nature of neuromodulation, these results warrant additional assessment and reevaluation by providers for the inclusion of cervical SCS as a treatment option for their members, where appropriate.

References1.Deer T, and Masone RJ. (2011). Spinal Cord Stimulation: Indications and Selection. In Atlas of Implantable Therapies for Pain. (pp.12) New York, NY: Springer Science+Business Media, LLC.

2.Deer T. Spinal Cord Stimulation for the Treatment of Chronic Pain. Anesthesiology News Special Edition 2010.

3.Forouzanfar T. et al, (2004). Spinal cord stimulation in complex regional pain syndrome: Cervical and lumbar devices are comparably effective. British J of Anaesthesia. 92(3), 348-353.

4.Whitworth L. A. and Feler C. A., (2003). C1-C2 sublaminar insertion of paddle leads for the management of chronic painful conditions of the upper extremity. Neuromodulation. 6(3), 153-7.