Transcript High-Frequency Spinal Cord Stimulation Therapy in Failed Back

High-Frequency Spinal Cord Stimulation Therapy
in Failed Back Surgery Syndrome Patients
with Predominant Back Pain
Adnan Al-Kaisy1, Jean-Pierre Van Buyten2, Stefano Palmisani1, Thomas Smith1, Iris Smet2
1St
Thomas' hospital, London, United Kingdom, 2AZ Nikolaas, St Niklaas, Belgium
Disclosure
Study supported by grant from Nevro Corp (Menlo Park, CA)
CAUTION – Nevro’s Senza™ system is an investigational device limited by Federal (USA)
law to investigational use. The device is approved for use in the European Union.
2
Most common locations of chronic pain
5%
8%
24%
15%
9%
6%
18%
16%
14%
8%
Introduction
FBSS:
Each year, more than 1 million spinal surgeries are performed in the US with 400,000 cases
being instrumented. 1
Roughly half of these are in the lumbosacral area. 2
Despite surgery, approximately 30% of these patients fail to improve, as shown by persistent
back pain. 2
SCS:
Traditional SCS is a well-accepted option for Failed Back Surgery Syndrome (FBSS)
patients with predominantly neuropathic leg pain. 1, 2
However, providing adequate and sustained back pain relief for patients with predominant
back pain remains more challenging. 1, 2
1 Frey,
2
Manchikanti, Benyamin, et al. Spinal Cord Stimulation for Patients with Back Surgery Syndrome: A Systematic Review. Pain Physician. 2009; 12:379-397.
Van Buyten JP, Linderoth B. “The Failed Back Surgery Syndrome”: Definition and therapeutic algorithms: An Update. Eur J of Pain Suppl. 2010;4:273-286.
High-Frequency SCS
Senza High-Frequency SCS system is a novel SCS system allows pulse rate up to 10
kHz.
Surgical technique similar to traditional SCS, however, a useful difference:
• Traditional SCS requires intraoperative paresthesia mapping
• Potentially uncomfortable for patient
• Can lead to wide range in procedure times
• HF-SCS lead positioning is more efficient:
• No paresthesia mapping needed
• Anatomically positioned
• Overlapping leads along midline
 Shorter, more predictable procedure times
High-Frequency SCS & FBSS
Senza was evaluated for use in the treatment of chronic pain in a prospective, open label
study. 3
• The study trialed 83 patients with or without prior surgery
• The study demonstrated the safety and efficacy of the novel therapy
• A subset analysis was conducted for the FBSS subset
• This subset includes 67 patients
• The patients were followed-up to 12 months
3 Van
Buyten et al, High-Frequency Spinal Cord Stimulation for the Treatment of Chronic Back Pain Patients: Results of a Prospective Multicenter
European Clinical Study. Neuromodulation. Accepted for publication
Baseline Demographics
Baseline Demographics
(n=67)
Mean age in years
Gender
49.6 ± 9.5
54% Female
Mean years since back
pain diagnosis
10
Predominant back pain
91%
Failed traditional SCS
18%
VAS Back (SD)
8.4 ( 1.2)
VAS Leg (SD)
5.4 ( 3.2)
Mean # of prior
surgeries (range)
History of back surgery:
spinal fusion
discectomy
laminectomy
disc replacement
2 (1-5)
52%
42%
40%
13%
Trial Results
57/66 patients (86%) had successful trial
(> 50% pain relief) and went to permanent
implant.
Notable results given significant number of
difficult-to-treat patients:
• 91% of FBSS cohort had predominant back
pain, which doesn’t respond well to traditional
SCS
• 18 % of FBSS cohort previously failed
traditional SCS
Note: 1 patient did not complete the trial
Pain Relief at 12 Months
Average Visual Analog Scale (VAS) for Pain
(mean + SEM)
Significant and
sustained back
pain & leg pain
relief despite
difficult-to-treat
population.
70% of the
patients had ≥
50% back
pain relief at 12
months.
N=57
N=57
N=54
p < 0.001
p < 0.001
Note: Subjects who have successfully passed the trial and received permanent implant
Improved Function at 12 Months
Severe
disability
Average Oswestry Disability Index
(mean + SEM)
Sustained
reduction in
disabilities.
15 point
decrease in
ODI at 12
months.
Low
disability
N=56
N=56
N=53
p < 0.001
p < 0.001
Excellent Safety Profile
Device related Serious Adverse Events were consistent with
standard SCS practice:
SAE
Number of Events
Pocket Pain
4
Wound Infection
3
Lead Migration
2
Loss of Pain Relief
1
Suboptimal Lead Placement
1
• There were no therapy-related neurological findings.
• No device had to be explanted due to battery life issues.
Summary & Conclusions
Despite advances in traditional SCS (i.e. transverse tripole, triangular stimulation, etc),
providing relief to FBSS patients with predominant axial low back pain remains very
difficult.
This 67 patient analysis of High-Frequency SCS on FBSS patients shows:
• High trial success rate despite difficult to treat patients (91% of the cohort had
predominant back pain)
• 86% trial phase success rate
• Significant and sustained relief for both back pain and leg pain
• 70% responder rate at 12 months
• Sizeable and durable improvement in function
• 15 point reduction in ODI at 12 months
• HF-SCS should be considered as a leading therapeutic option for FBSS patients (even
those with predominant back pain)
CAUTION – Nevro’s Senza™ system is an investigational device limited by Federal
(USA) law to investigational use. The device is approved for use in the European Union.