Transcript Diagnosis and Treatment of Spinal Pain

Low Back
Pain: Novel
Solutions
Douglas Keehn, DO
Advanced Pain Management
Madison, WI
Objectives
• Have awareness of the medical, social and
economic impact of spinal pain
• Understand the role of interventional
diagnostic approaches to evaluating spinal
pain
• Be aware of interventional treatments
available for the treatment of spinal pain
Epidemiology
• Pain is the second most common complaint of
people seeking medical advice
• < 3 hours training of primary care physicians
• 60-90% U.S. adults will have back pain in their
lifetime, 50% annual incidence
• 30% with back pain develop chronic pain
Skovron ML: Epidemiology of low back pain. Bailliere's Clin Rheum 6:559-573, 1992.
Epidemiology
• “The annual cost of chronic pain in the U.S. is
estimated to be $560-635 billion including
healthcare expenses and lost productivity”
• Most frequently filed workers’ compensation
claim
• Most common reason for disability in patients
<45 years
Institute of Medicine. Relieving Pain In America: A Blueprint for Transforming Prevention, Care, Education and
Research. Washington, D.C.: The National Academies Press. 2011.
ESTIMATED EPIDEMIOLOGY OF
SPINAL PAIN
Low Back
Neck
IDD/DDD
20-50%
20-30%
Facet joint mediated pain
15-45%
50-60%
Disc herniation
3-46%
3-50%
Spinal stenosis
2-12%
2-15%
Myofascial
10-20%
10-20%
Other causes
2-10%
2-10%
Spinal Pain
• Radicular
– Inflammation of nerve
root
• Axial
– Myofascial
– Facetogenic
– Discogenic
Radicular Pain vs. Radiculopathy
• Radicular pain in
distribution of nerve
secondary to
inflammation
• Radiculopathy is a
specific neurologic
deficit
– May be painless
Inflammation and Radicular Pain
• Macnab I, Pain, 1971: Balloons in neural
foramina of normal nerves and those with
associated disc herniations
– Normal levels produced painless neuro deficits
– Affected levels produced pain
Radicular Pain Basics and Basic Science
• Chemical irritation from cytokine exposure to nerves:
decreased NCV, damage to myelin, edema, coagulation
• Inflammatory mediators increase dorsal root ganglion
sensitivity and ectopic firing
• Nucleus pulposus when placed on to the DRG causes
excitation and mechanical hypersensitivity
• Only inflamed NR is painful if pressed or stretched
Kawakami M et al Spine 19:1780-1794,1994. Lee HM et al Spine 23:1191-1196, 1998. Kirkaldy-Willis WH Spine
9:49-55,1984. Tsuneo T, Spine 26:940–945, 2001.
Corticosteroid Effects
• Suppression spontaneous ectopic firing
• Antinociceptive in themselves
– Blocks C-fiber transmission
– Transmission normalized upon removal of the
corticosteroids
Devor M et al. Corticosteroids suppress ectopic neural discharge originating in experimental neurons. Pain
1985;22:117-122.
Johansson A et al. Local cortiocosteroid application blocks transmission in normal nociceptive C fibers. Acta
Anaesthiol Scand 1990;34:335-8Lieberman AC et al. Intracellular molecular signalling Ann NY Acad Sci
2009;1153:6-13
Epidural Steroid Injections: Indications
• Used in conjunction with conservative
management
– PT and/or manipulative medicine
– NSAIDs
– Muscle relaxants
– Antiepileptics
– Opioids?
Epidural Steroid Injections: Indications
• Radicular Pain
– Disc herniation
– Herpes zoster
• Spinal Stenosis
• Discogenic Pain
Epidural Steroid Injection
• Three routes:
– Caudal
– Interlaminar
– Transforaminal
Caudal ESI
Interlaminar ESI
• Cervical
• Thoracic
• Lumbar
Interlaminar ESI
L3
L4
S1
Transforaminal ESI
Transforaminal Lumbar ESI
Complications and Adverse Effects
• Headaches
• Infection
• Bleeding
– Coumadin Ticlid, Plavix, Asprin, Lovenox, etc.
• Paraplegia
• Nerve root injury
• Miscellaneous
– Increased blood sugar
– Hypertension
– Pedal edema, CHF
Lumbar Stenosis: Types of Physical Therapy
• Multicenter RCT
– Manual physical therapy, body
weight supported treadmill
walking and exercises (N=29)
– Lumbar flexion exercises and
treadmill walking (N=29)
– Outcome measures
• ODI
• Global rating of change
• At 0, 6 weeks, 12 months
Whitman, SPINE 2006
Lumbar Stenosis: TENS, Brace, Medications
Bracing:
• The use of a lumbosacral corset/brace can increase walking
distance and decrease pain in patients with LSS
• There is no evidence that results are sustained once the brace
is removed
Insufficient evidence to address the role of:
• Traction, electrical stimulation or TENS
• NSAIDs, narcotics
• Muscle relaxants
• Analgesics
• Oral Prednisone
NASS Clinical Guidelines for diagnosis and treatment of degenerative lumbar spinal stenosis, 2007
Lumbar Stenosis: Adding gabapentin
• N=55, randomized 2 groups
– PT, Brace, NSAIDs vs. PT, Brace, NSAIDs and Gabapentin
• Gabapentin 900 mg/day — increased to 2,400 mg/day
• Follow-up 15 days, monthly up to 4 months
• Gabapentin group showed better increase in walking distance,
as well as better pain scores
– Mean VAS change after 4 months
• Treatment group (7.0/2.9)
• Control group (6.7/4.7)
Yaksi, SPINE 2007 32(9)
Epidural Steroids and Spinal Stenosis
– Improvement in VAS pain scores correlated well
with severity of symptoms and radiographic
severity, as well as number of levels affected,
except in patients classified as severe with >3
lumbar levels affected
– Grade of nerve root compromise on MRI
correlated with ESI outcomes but not duration
or S&S
Kapural et at. Clin J Pain 2007: 23: 7
Ghahreman A, Bogduk N. Predictors of favourable response to transforaminal injection of steroids in patients with lumbar radicular pain due
to disc herniation. Pain Med 2011:12;871-9
Herniated Nucleus Pulposus
• With (1.8) transforaminal
steroid injection, 75% of
patients (N=69) had good
outcomes at 80 weeks
• Transforaminal > Interlaminar
> Caudal
• Cost effective
Lutz GE, Vad VB, Wisneski RJ. Fluroscopic transforiminal lumbar epidural steroids: An
outcome study. Arch Phys Med Rehabil 79:1362-1366,1998
Manchikanti L, Pakanati RR, Pampati V. Comparison of three routes of epidural steroid
injections in low back pain. Pain Digest 9:277-285,1999
Zennero H, Dousset V, Viaud B et al. Periganglionic foraminal steroid injections
performed under CT control. AJNR Am J Neuroradiol 19:349-352,1998
Manchikanti L. Focused review: Transforaminal lumbar epidural steroid. Pain Physician.
3:374-398,2000
ESI Efficacy
• Manchikanti et. al.: Double-blind, randomized
placebo controlled studies evaluating ESI for
treatment
– Chronic discogenic pain
– Chronic radiculitis
– Lumbar post laminectomy syndrome
– Spinal stenosis
Manchikanit L, Singh V, Cash KA, et al.: Preliminary results of a randomized , equivalence trial of fluoroscopical caudal epidural steroid injections in
managing chronic back pain. Pain Physicinan. 11:801-848 2008
ESI Efficacy
• Manchikanti et. al.:
– Demonstrated efficacy in all 4 groups with
functional improvement noted in:
• Disc herniation and radiculitis group (79-91% )
• Post laminectomy syndrome (55%)
• Spinal stenosis (70%)
Can ESIs Prevent Surgery?
• 91 patients with
HNP referred to
spine surgeons
• 56% avoided
surgery because
of relief from 1 or
more TF ESI
Manson MA, McKeon MD, Abraham EP. Transforaminal epidural steroid injections prevent the need for surgery in patients with sciatica
secondary to lumbar disc herniation: a retrospective case series. Can J Surg 2013;56:89-96
Meta analysis of 26 trials… between one-third and half of patients considering surgery who undergo ESI can avoid surgery. Bicket MV et
al. Epidural injections in prevention of surgery for spinal pain: systematic review and meta-analysis of randomized controlled trials. Spine
J 2015;15:348-62
Can ESIs Save Money?
• The cost utility of epidural injections
is superior to numerous other
modalities of treatments including
“usual care,” spinal cord stimulation
and surgical interventions
Spijker-Huiges A, Vermeulen K, Winters JC, van Wijhe M, van der Meer K. Epidural steroids for lumbosacral radicular syndrome compared to
usual care: quality of life and cost utility in general practice. Arch Phys Med Rehabil 2015; 96:381-387.
Manchikanti L, Falco FJE, Pampati V, Cash KA, Benyamin RM, Hirsch JA. Cost utility analysis of caudal epidural injections in the treatment of
lumbar disc herniation, axial or discogenic low back pain, central spinal stenosis, and post lumbar surgery syndrome. Pain Physician 2013;
16:E129-E143.
Taylor RS, Ryan J, O’Donnell R, Eldabe S, Kumar K, North RB. The cost-effectiveness of spinal cord stimulation in the treatment of failed back
surgery syndrome. Clin J Pain 2010; 26:463-469.
ESTIMATED EPIDEMIOLOGY OF
SPINAL PAIN
Low Back
Neck
IDD/DDD
20-50%
20-30%
Facet joint mediated pain
15-45%
50-60%
Disc herniation
3-46%
3-50%
Spinal stenosis
2-12%
2-15%
Myofascial
10-20%
10-20%
Other causes
2-10%
2-10%
Question
What role does
imaging play in the
diagnosis of chronic
axial low back pain?
Imaging in Chronic Axial Low Back Pain
• MRI correlates poorly with source of pain
–
–
–
–
Boden SD et. al., JBJS,72: 403-8, 1990
Jensen M et. al., N Eng J Med, 331:69-73, 1994
Boss N et. al., Spine 20: 2613-25, 1995
Yu SW et. al., Am J Neuroradiol 10:1077-81, 1989
• CT correlates poorly with source of pain
– Schwarzer AC et. al., Spine, 20:907-912, 1995
– Weisel et. al., The incidence of positive CAT scans in an asymptomatic group of patients.
Spine, (9), 549-551, 1984
– Rothman RH. The study of computer assisted tomography, Spine 9;548,1984
• X-ray correlates poorly with source of pain
– Jajic I et. al., Clin Rheumatol 6:39-41, 1987
Spinal Facet Joint
Cervical Pain: Facets
• Stimulation of
zygapophyseal
joints causes pain in
normal volunteers
• In patients with
neck pain produces
relief with
anesthetizing joints
Dwyer et al Spine 15:453-457,1990
Bogduk Spine 7:319-330,1982
Wedel & Wilson. Reg Anesth 10:7-11,1985
Dussault & Nicolet. J Can Assoc Radiol 36:79-80,1985
Facet Referred Pain
•
•
•
•
•
•
Gluteal
Trochanteric
Proximal thigh
Groin
Lumbar
Considerable
overlap
Fukui s, Ohseto K, Shiotani M, Ohno K,
Karasawa H, Naganuma Y. Distribution of
referred pain from lumbar zygapophyseal joints
and dorsal rami. Clin J Pain 13:303-307,1997
Diagnosing Facet Syndrome
Neither
clinical
examination
nor imaging
is reliable for
diagnosis
Schwarzer A, Derby R, Aprill CN et al. Pain from lumbar zygapophyseal joints. A test of two models J Spine Dis 7:331-8: 1994
Medial Branch Block
Treatment - Facet Mediated Pain
• Conservative management
– Lifestyle changes
– Physical therapy
– Manual medicine
– Pharmacotherapy
• NSAIDs
• Muscle relaxants
• Interventional management
– Facet injections
– Medial branch blockade and RF denervation
Lumbar Facet Radiofrequency
Radiofrequency Ablation
• 60% of patients >90% relief, 87% had >60%
relief at 12 months. (Dual comparative
anesthetic blocks)
– Dreyfuss P, et. al., Efficacy and validity of radiofrequency neurotomy for
lumbar zygapophysial joint pain. Spine 25:1270-7,2000
• 253 days before 50% pre-RF symptoms
returned
– Lord SM, et. al., A randomized double blinded controlled trial of percutaneous
radiofrequency neurotomy for the treatment of chronic cervical zygapophysial joint
pain. N Engl J Med 335:1721-1726,1996
Radiofrequency Ablation
“The evidence for conventional
radiofrequency neurotomy in
managing chronic low back pain of
facet joint origin in the lumbar
spine is good for short- and longterm relief.”
An Update of Comprehensive Evidence-Based Guidelines for Interventional Techniques in Chronic Pain: Part II: Guidance and
Recommendations. Manchikanti, L et al. Pain Physician: April 2013; 16:S49-S283
ESTIMATED EPIDEMIOLOGY OF
SPINAL PAIN
Low Back
Neck
IDD/DDD
20-50%
20-30%
Facet joint mediated pain
15-45%
50-60%
Disc herniation
3-46%
3-50%
Spinal stenosis
2-12%
2-15%
Myofascial
10-20%
10-20%
Other causes
2-10%
2-10%
Discogenic Pain
• Discogenic pain does not refer to nerve root
pain caused by disc herniation
• Discogenic pain refers to the pain arising from
the disc itself
Discogenic Pain
• The outer third of the annulus is richly innervated
• This innervation constitutes the anatomic substrate for discogenic pain
Discogenic Pain: Clinical Features (IASP: 1994)
• Lumbar spinal pain, with or without referred
pain in the lower limb girdle or lower limb;
aggravated by movements that stress the
symptomatic disc
Discogenic Pain - Imaging
•
•
•
•
•
Decreased disc height
Endplate changes
Decreased T2 signal
High intensity zone
May be asymptomatic
Discogenic Pain - Treatment
• Some evidence for ESI
• Conservative management predominates
– Lifestyle changes
– Manual medicine
– Medication management
• Evidence for surgical intervention limited
• Spinal cord stimulation?
Neurostimulation
• Neurostimulation is a pain
treatment that delivers low
voltage electrical stimulation to
the spinal cord to inhibit or
block the sensation of pain
• Trial screening to evaluate
patient response to
neurostimulation is performed
prior to committing to a full
implant
Neurostimulation Theory
• Gate control theory
– Melzack and Wall (1965)
• Aβ-fibers
– Myelinated (fast)
– Light touch
– Vibratory sense
• C-fibers
– Unmyelinated (slow)
– Pain
Overview of Trial Procedure
• A percutaneous lead is positioned in
the epidural space on the dorsal aspect
of the spinal cord at the appropriate
nerve root level(s)
• Electrical current from the lead
generates paresthesia that can be
adjusted in intensity and location to
achieve the best pain coverage
• Leads are attached to an external pulse
generator (screener), which supplies
the current
• Patients can use the screener to adjust
stimulation to meet pain management
needs
Indications for Neurostimulation
Most Common Indications for Neurostimulation1-3
Post-laminectomy associated
chronic pain
Refractory neuropathic back and
leg pain
Complex Regional Pain Syndrome
Types I and II
Neurostimulation is perhaps best utilized for the treatment of
neuropathic pain of peripheral origin vs. nociceptive origin.1,2
1. Meyerson BA, Linderoth B. Neurol Res. 2000;22:285-292. 2. Gybels J et al. Eur J Pain.
1998;2:203-209. 3. De Andrés J, Van Buyten J-P. Pain Practice. 2006;6:39-45.
Patient Selection
•
Objective evidence of pathology
– Use appropriate diagnostic studies to establish pain etiology, to rule out other
causes such as a tumor
•
Inadequate pain relief and/or intolerable side effects after treatment with
more conservative therapies
•
Psychological evaluation
– Is the patient physically and mentally able to handle the procedure and
associated maintenance and/or follow-up?
•
Absence of drug-seeking behavior
•
Patients with predominant nociceptive pain may not respond to treatment
with neurostimulation
•
Potentially adverse psychosocial factors should also be considered prior to
treatment with neurostimulation:
– Noncompliance to treatment
– Severe depression
– Untreated drug dependency
Advantages of Implanted Neurostimulators for Pain
• Effective method of pain control1
• Screening trial allows patient
response to be tested before a full
implant
• Systems reprogrammable without
surgery
• Patient control within physician set
limits
• Nondestructive procedure compared
with surgical alternatives
• Reduction of pain medications2
1. PMA#: Synergy - P840001/S042 approved 11/19/99, Restore - P840001/S074 approved 4/8/05. 2. North RB et al. Neurosurgery.
2005;56:98-107.
Neurostimulation: Pain Relief
Failed Back Surgery
Syndrome: Percentage of
patients receiving
satisfactory pain relief up
to 1 year and 22 years
(n=220)1
83.6%
60.0%
Up to Year 1
Up to Year 22
Long-term FBSS Pain
Relief
1. Kumar K et al. Neurosurgery. 2006;58:481-496.
Neurostimulation: Pain Relief
CRPS I/II: Percentage of internalized patients
receiving satisfactory pain relief up to 1 year
and 22 years (n=22)1
87.5%
Peripheral Neuropathy: Percentage of
internalized patients receiving satisfactory pain
relief up to 1 year and 22 years (n=17)1
82.4%
72.0%
71.0%
Up to Year 1
Up to Year 22
Up to Year 1
Long-term CRPS I and II
Pain Relief
1. Kumar K et al. Neurosurgery. 2006;58:481-496.
Up to Year 22
Long-term Peripheral
Neuropathy Pain Relief
Neurostimulation: Pain Relief
Sustained Pain Relief Over Time With Neurostimulation1
% Patients With At Least
50% Pain Relief
100
80
60
40
20
0
0
12
24
36
48
60
72
84
Duration of Follow-up (Months)
96
108
62% of patients with FBSS achieve at least 50% sustained,
long-term pain relief with neurostimulation.1
1. Taylor R. Spine. 2005;30:152-160.
Patient Satisfaction
Patient Satisfaction With Neurostimulation1,2
Percent of Patients
100%
88%
70%
80%
60%
40%
20%
0%
Unspecified FBS
Low Back Pain
88% of patients with unspecified FBSS were satisfied with
neurostimulaiton treatment1
70% of patients with predominantly axial low back pain were satisfied
with neurostimulation treatment2
1. Kumar K et al. Neurosurgery. 2002;51:106-116. 2. Ohnmeiss DD, Rashbaum RF. Spine J. 2001;1:358-363.
Patient Satisfaction
Patient Satisfaction with Neurostimulation for Predominant
Complaints of Chronic Intractable Low Back Pain
(% of Patients)1
78.1%
75.8%
A majority of patients would have neurostimulation
again and/or recommend the treatment
Have Neurostimulation Again
Recommend Neurostimulation
1. Ohnmeiss DD, Rashbaum RF. Spine J. 2001;1:358-363.
Cost-Effectiveness
Difference in Cumulative Costs ($Can)
Neurostimulation for FBSS resulted in a cost savings after 2.5 years
compared with conventional medical management1
Break-Even Point
2.5 Years
10,000
5,000
0
-5,000
-10,000
-15,000
-20,000
1 Year
2 Years
3 Years
Time Post-Implant
1. Kumar K et al. Neurosurgery. 2002;51:106-116.
4 Years
5 Years
Advantage of Earlier Intervention
A retrospective study showed an inverse relationship between the
onset of the chronic pain syndrome and SCS therapy success.1
78%
Patient Success Rate (%)
83%
42%
35%
10%
<2
2 to 5
5 to 8
8 to 11
11 to 15
Time Until Intervention (Years)
1. Kumar K et al. Neurosurgery. 2006;58:481-496.
5%
>15
PROCESS Study design
• International RCT on the effectiveness and cost-effectiveness of SCS vs.
CMM in patients with FBSS
• 100 patients with chronic neuropathic pain predominantly in the leg(s)
following at least one spinal surgery, randomized 1:1
• 12 centers in Europe, Australia
• Pragmatic trial:
– Intent-to-treat (ITT) analysis until 6 months with crossover allowed after
6 months
– Long-term follow-up to 24 months
• Treatment definition
– CMM: any therapy advised by a physician, except reoperation and intrathecal
drug delivery (IDD)
– SCS (+CMM): implantable stimulation system (Synergy® system)
PROCESS Study design: Sample Size and Objectives
• Assumptions for sample size based on previous trial:1
– 42.5% of SCS patients reach ≥50% leg pain relief at 6 months
– 14.5% of CMM patients reach ≥50% leg pain relief at 6 months
– 20% attrition
• Primary outcome:
– Proportion of patients with ≥50% leg pain relief at 6 months
(≥50% reduction in leg VAS)
• Secondary outcomes evaluated at 1, 3, 6, 9, 12, 18 and 24 months:
–
–
–
–
–
–
–
Pain relief (leg and back VAS)
Quality of life (SF-36® and EQ-5D)
Function (Oswestry Disability Index)
Patient satisfaction
Drug/nondrug therapy use
Time away from work
Adverse events
1. North et. al., Neurosurgery 2005.
Primary Outcome at 6 Months
≥50% leg pain relief
Significantly more SCS patients (48% vs 9%) achieved the primary outcome (P<0.001)
Secondary Outcome at 6 Months
VAS leg pain
Significantly greater reduction in leg pain with SCS (P < 0.0001)
*
*
*
*
*
**
**
Secondary Outcome at 6 Months
VAS back pain
Significantly greater reduction in back pain with SCS (P = 0.008)
*
*
*
*
*
Secondary Outcome at 6 Months
•
•
•
•
Medication intake
Significantly fewer patients on anticonvulsants in SCS group (P = 0.02)
Trend regarding antidepressants (P = 0.06)
No difference in opioids and NSAIDs
a
Baseline
6 months
CMM
CMM
SCS
SCS
100%
90%
Patients taking medication (%)
Patients taking medication (%)
100%
80%
70%
60%
50%
40%
30%
20%
10%
0%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
Opioids
NSAIDs
Antidepressants Anticonvulsants
Opioids
a
NSAIDs
Antidepressants Anticonvulsants
Significant difference P=0.02 between groups at 6 months
Mechanism of Action High Frequency Stimulation
• Anatomically placed
leads
• 10K Hz
• SCS releases GABA
• High frequency allows
natural firing rate of
neurons, higher
efficiency
High Frequency vs. Traditional SCS Responder Rates
Leg Pain
100%
84.3%
78.7%
76.4%
80%
60%
51.9%
51.3%
43.8%
40%
20%
0%
3
6
Leg Pain Responder Rate
Back Pain Responder Rate
Back Pain
100%
83.1%
80.9%
78.7%
80%
60%
55.0%
54.4%
51.3%
40%
20%
0%
3
12
6
12
month
month
Test (HF10 therapy)
Control (Traditional SCS)
Analysis of permanent implant population
Superiority p-value <0.001
Pain Score was Primary Endpoint
100%
Superiority p-value <0.001
Met Primary Endpoint
80.9%
80%
60%
42.5%
40%
• Average back pain of ≥5/10
• Average leg pain of ≥5/10
• Severely disabled or
crippled as defined by an
Oswestry Disability Index
score of 41-80 out of 100
• Primary endpoint involves
50% back pain reduction
at 3months
20%
89
80
0%
Treatment group
(HF10 therapy)
Control group
(Traditional SCS)
Analysis of permanent implant population
Superior Responder Rates with HF10 Therapy
Results better and more enduring
At 12 months, mean back pain VAS decreased 66% with HF10 therapy compared to
a decrease of 45% for traditional SCS therapy
10
9
8
7
6
5
4
3
2
1
0
4.3
2.5
0
3
6
9
Assessment (months)
Control (Traditional SCS)
Back Pain Relief
(change in VAS score)
Back Pain (VAS score)
Test (HF10 therapy)
100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
12
Superiority p-value <0.001
66.4%
44.7%
0
3
6
9
Assessment (months)
12
Analysis of permanent implant population
Superior ODI Improvements with HF10 Therapy
At 12 months, 63% of HF10 therapy subjects had minimal or moderate
disability compared with 46% of traditional SCS subjects
2%
100%
% Subjects with ODI Level
22%
10%
20%
35%
80%
44%
60%
40%
71%
77%
37%
20%
63%
46%
1%
9%
9%
Baseline
12 months
Baseline
CONTROL
(TRADITIONAL SCS)
Crippled
46%
Severe
17%
12 months
TEST
(HF10 THERAPY)
Moderate
Minimal
N = 171
ODI = OSWESTRY DISABILITY INDEX
SUPERIORITY DEMONSTRATED (P=0.03)
Analysis of permanent implant population
HF SCS: Decreased Opioid Use from 84 mg to 27 mg
% of Patients Using Opioids
Mean mg Morphine per Patient
68 % reduction in dose
34% reduction in # patients
N=72
N=68
N=65
N=72
N=68
N=65
* p-value < 0.001
Neural Targeting SCS
• Multiple Independent Current Control (MICC)
– One current source for each contact vs. one
current or voltage source for all contacts
– Fractionalization for fine movement of the
Central Point of Stimulation (CPS)
9 CPS
10,000 CPS
Neural
target
Single
Source System
NOT
Targeted
Multiple
Source System
Targeted
Neural Targeting SCS Model
Resistivity values and density of nodes of the FEM domains
Lee, D. et. al., “Predicted effects of pulse width programming in spinal cord stimulation: a mathematical modeling study,” Med Biol Eng Comput
(2011) 49:765–774.
Neural Targeting Clinical Data
• Retrospective, consecutive patients
– 213 consecutive patients
– Across 13 sites
– Long-term follow-up to 2 years
Neural Targeting Long-Term Results
• LUMINA Clinical Data
– Real world, multicenter, 213 patients, 24 month
follow-up
Overall Pain
Outcomes
Neural Targeting Long-Term Results
• LUMINA Clinical Data
– Real world, multicenter, 24 month follow-up
Low Back
Pain Only
Neural Targeting Long-Term Results
• LUMINA clinical data, 24 month follow-up
Neural Targeting Therapeutic Options
• Real-World Utilization of Multiple Waveforms
Single
Waveform
28%
Multiple
Waveforms
72%
N=800
RELIEF - Real-World Clinical Outcomes of Spinal Cord Stimulation: A Prospective Global Registry Study, Berg et al., NANS 2015
Incredible progress
in neuromodulation
for the pain patient
in 2016
“More than half of all patients with chronic painful conditions experience sustained and significant levels of pain reduction following SCS treatment.
Although only limited evidence exists for burst stimulation, there is now Level I evidence for both dorsal root ganglion SCS and high-frequency SCS that
demonstrates compelling results compared with traditional therapies. The body of evidence built on traditional SCS research may be redundant, with
newer iterations of SCS therapies such as dorsal root ganglion SCS, high-frequency SCS, and burst SCS. A number of variables have been identified that
can affect SCS efficacy: implanter experience, appropriate patient selection, etiologies of patient pain, existence of comorbidities, including
psychiatric illness, smoking status, and delay to SCS implant following pain onset. Overall, scientific literature demonstrates SCS to be a safe, effective,
and drug-free treatment option for many chronic pain etiologies.
Verrills P, Sinclair C, Barnard A. A review of spinal cord stimulation systems for chronic pain. J Pain Res. 2016 Jul 1;9:481-92. doi:
10.2147/JPR.S108884. eCollection 2016. Review
Acute to Chronic Pain Cycle
Pathophysiology of Maintenance
-Radiculopathy
-Neuroma traction
-Myofascial sensitization
-Brain pathology (loss, reorganization)
Psychopathology
of maintenance
Acute injury
-Encoded anxiety
and pain
dysregulation
- PTSD
-Emotional
allodynia
-Mood disorderNeurogenic
Inflammation
- Glial activation
- Pro-inflammatory
cytokines
- Blood-nerve barrier
disruption
Secondary
Pathology
-Muscle atrophy,
weakness
-Bone loss
-Depression
-Cortical atrophy
Central
sensitization
Peripheral
Sensitization
Na+ channels
Lower threshold
Disability
- Less active,
kinesiophobia
- Decreased
motivation
- Increased
isolation
- Role loss
Here is why EARLY referrals are critical
Delayed interventions = Poor outcomes
•
•
•
•
•
•
•
Facet RF: Cohen et. al., CJP 2007
Spine surgery: Quigley. Surg Neurol 1998, Jacobs Eur Spine J 2011
Epidural steroids: Kwon et. al., Skel Radiol 2007, Benzon Pain 1984
Pharmacotherapy for CRPS: Perez et. al., Pain 2003
IA injections for knee OA: Tanaka et. al., Rheum Int 2002
Physical therapy for DJD: Jansen et. al., Eur J Phys Rehabil Med 2010
Vertebroplasty: Ryu and Park J Korean Neurosurg Soc 2009
Take-Home Message: Intervene Early
Modern Pain Management:
A More Flexible Approach - Customized
• Different time frames
• Multiple therapies at one time
• Different starting points
Epidurals
Facets
SI Joint
Corrective
Surgery
Discectomy
Fusion
Intrathecal
therapy or
neurostimulation
Physical
therapy,
TENS
NSAIDs,
Over-the-counter
Drugs,
Lifestyle
modification
Long-term
oral
opioids
Chronic
Pain
Patient
Neuroablation
Prager J and Jacobs M. Evaluation of patients for implantable pain modalities: medical and behavioral assessment. Clin J Pain. 2001 Sep;17(3):206-14.