Successful Treatment of
Low Back Pain with a
Novel Neuromodulation Device
Iris Smet, MD1
Jean-Pierre Van Buyten, MD1
Adnan Al-Kaisy MB ChB FRCA2
1AZ
Nikolaas Hospital, Belgium
2Guy’s
and St. Thomas’ Hospital, United Kingdom
Conflict of Interest
• Primary Investigator; study sponsored by
Nevro Corporation, Menlo Park, CA
2
Key Challenges in SCS
• Treating back pain remains a challenge
– Leg pain component only
– PROCESS Study - Kumar, 2006
• Uncomfortable stimulation
– Patients experience “shocking” sensation
– Stimulation/posture adjustments required to decrease
uncomfortable stimulation
– Kuechmann, 2009
• Opioids remain part of treatment regimen
– Side-effects outweigh benefits
– Van Buyten and Linderoth, 2010
• Opportunity for SCS in treating back pain
3
Study Overview
• Purpose: Demonstrate effectiveness in chronic back and/or
leg pain patients
– First permanent implant study with this novel SCS
• Design: Prospective, Observational Study
• Population: Back pain score > 5 out of 10 on VAS
• Key Outcomes Measurements
–
–
–
–
Pain relief using Visual Analog Scale (VAS)
Functional improvements using Oswestry Disability Index
Opioid usage
Incidence of SCS-induced movement-dependent discomfort
4
Study Flow (St. Nikolaas Site)
Trialed
n=42
Failed Trials
• Up to 50 patients will be trialed
n=4
–
Successful Trials
n=38 (90%)
IPG Implanted
1 Month
• Permanent percutaneous lead trial
(Anchored & tunneled)
Ongoing trial.
Interim results
shown.
21 patients have
passed 6 month
visit.
3 Months
6 Months
Study is ongoing (interim results
shown)
Other patients
have yet to reach
6 month visit.
–
Duration 4 weeks +/- 2 weeks
• Anatomical not physiological lead
placement
• Adverse Events
–
Infection during trial phase(4), lead
migration(2), thrombosis(1),
edema(1), pocket pain(2),
sensation change(1), skin
irritation(2), infection during
perm(2)
5
Patient Population
42 Patients Trialed to-date; Mean age is 49 ± 8.1 years, 76% are females
Surgical History
FBSS Patients
(N=33)
Patients w/ no prior spine surgery (N=9)
21%
79%
•
Refractory to conservative treatments (e.g.,
radiofrequency) with no long-term benefit
•
Considered not to be surgical candidates.
•
Neurosurgeon evaluated for mechanical
instability and referred non-surgical candidates
to the pain clinic.
Pain Type
Predominant
Leg pain
patients
(N=6)
14%
Predominant Back Pain Patients
(N=36)
86%
6
Back and Leg Pain Reduction
Average Visual Analog Scale (VAS) for Pain
(mean +/- SEM)
N=29
N=28
Back pain VAS: p-value < 0.001
Leg pain VAS: p-value < 0.001
N=21
Back pain VAS: p-value < 0.001
Leg pain VAS: p-value < 0.001
Note*: Baseline VAS shown above is from patients who passed 3 month visit. One patient missed 3 month visit, but came for 6 month visit.
7
No Uncomfortable Stimulation
Adjust Stimulation Before or
After Position Change
% of Patients
% of Patients
Uncomfortable Stimulation
due to Position Change
•
No uncomfortable stimulation with position change
•
No adjustment of stimulation required with postural change
*Kuechmann, 2009
8
Reduction in Opioid Use
N=21
•
N=21
Only 14% of patients are using
opioids at 6 months
N=21
•
N=21
Only 3 mg of morphine per patient
at 6 months
9
Improvement in Function and Sleep
Severe
disability
Average Oswestry Disability Index
(mean +/- SEM)
Number of Sleep
Disturbances per Night
(mean +/- SEM)
9 point reduction was
observed in other SCS
studies (1)
Low
disability
N=29
N=28
p-value < 0.001
N=21
p-value < 0.001
N=21
N=21
p-value < 0.001
• Functional Improvement: 21 point reduction at 6 months
• Sleep Improvement: 87% reduction in sleep disturbances
(1) Other
SCS study results: 9 point reduction (Taylor, 2005)
Note*: Baseline ODI shown above is from patients who passed 3 month visit. One patient missed 3 month visit, but came for 6 month visit.
10
Summary
• Sustained back & leg pain relief at 6 months*
• Significant elimination and reduction of opioid
usage*
• Improved patient functionality and sleep*
• No sensation of paresthesia
• No uncomfortable stimulation
• Proportion and type of adverse events are
consistent with other SCS studies conducted
Note*: In comparison to baseline
11
Thank you!
12