Department of Neurosurgery, Feinberg School of Medicine, Northwestern University Spinal Cord Stimulation: Indications and Patient Selection Joshua M

Department of Neurosurgery, Feinberg School of Medicine,Department of Neurosurgery, Feinberg School of Medicine, Northwestern UniversityNorthwestern University

Spinal Cord Stimulation: Spinal Cord Stimulation:

Indications and Patient SelectionIndications and Patient Selection

Joshua M. Rosenow, MD, FACSJoshua M. Rosenow, MD, FACSAssociate Professor of Neurosurgery

Director, Functional Neurosurgery

Northwestern Memorial Hospital


DisclosuresDisclosures

Consultant:

Boston Scientific Neuromodulation

Medtronic Navigation


FBSS EtiologiesFBSS Etiologies

Poor patient selection Abnormal psychometrics Chronic pain behavior Unreachable expectations

Incorrect diagnosis Wrong procedure

Wrong level or site Poor technique

Nerve root injury Iatrogenic instability or flat back syndrome Pseudarthrosis Incomplete decompression or incomplete correction of deformity

Progressive disease Recurrent disk herniation or spinal stenosis Transition syndrome


Indications for SurgeryIndications for Surgery

Compressive lesion

Associated radiculopathy

Demonstrable neurologic deficit

Clear instability / deformity


CRPS Diagnostic CriteriaCRPS Diagnostic Criteria


Revised Diagnostic CriteriaRevised Diagnostic Criteria

Pain and sensory changes disproportionate to the injury in magnitude or duration

At least 1 symptom in 3 or more categories and 1 sign in 2 or more categories

Sensory Vasomotor Sudomotor/edema Motor/trophic

Harden RN and Bruehl SP. Introduction and diagnostic considerations. Harden RN and Bruehl SP. Introduction and diagnostic considerations. Complex Regional Pain Complex Regional Pain Syndrome: Treatment Guidelines.Syndrome: Treatment Guidelines. RSDSA press. 2006:1-11 RSDSA press. 2006:1-11..


Surgical ContraindicationsSurgical Contraindications

Thecal sac compression by tumor

Significant spinal deformity

Severe emaciation

Significantly low WBC, plt

Coagulopathy

Ongoing infection

Unsuccessful trial


SCS: Patient SelectionSCS: Patient Selection

Pain syndrome amenable to stimulation Radicular preferable to axial Neuropathic preferable to nociceptive

Failed reasonable medical management Several pharmacologic classes Dose titration until adverse side effects or lack of response noted

Surgical disease ruled out Reoperation vs. stim? Not surgical candidate?

Pain psychological evaluation


Patient FactorsPatient Factors

Set appropriate expectations!!!! Takes time, but will be worth the investment

They need to understand this is not a cure!

Seeing the patient multiple times before moving to a trial helps gauge their goals of therapy and probable compliance level


Patient FactorsPatient Factors

Can they be a reliable partner with a subjective therapy?

Can they give appropriate feedback in the OR?

Can they manage the device? Rechargeable vs primary cell IPG


Other TreatmentsOther Treatments

Should proceed in parallel Psychological counseling Behavioral treatments Physical therapy and conditioning Vocational counseling and rehab Implantables can’t fix everything!


Psychosocial FactorsPsychosocial Factors

Present in ALL chronic pain patients Can include:

Depression Personality disorders Drug and alcohol problems Return to work issues Social and family discord Many others


Pain Psychology Pain Psychology

Spine surgery success in the presence of:Spine surgery success in the presence of:Childhood physical or sexual abuse,Childhood physical or sexual abuse,Emotional neglect/abuseEmotional neglect/abuseAbandonmentAbandonmentChemically dependent parents:Chemically dependent parents:

# Factors# Factors Surgical SuccessSurgical Success

11 95%95%

1-2 1-2 73%73%

3 or more 3 or more 15%15%

Spine surgery success in the presence of:Spine surgery success in the presence of:Childhood physical or sexual abuse,Childhood physical or sexual abuse,Emotional neglect/abuseEmotional neglect/abuseAbandonmentAbandonmentChemically dependent parents:Chemically dependent parents:

# Factors# Factors Surgical SuccessSurgical Success

11 95%95%

1-2 1-2 73%73%

3 or more 3 or more 15%15%

(Shofferman et al., 1992)(Shofferman et al., 1992)


Predictive value of psychological testingPredictive value of psychological testing

Many studies have examined the value of psychological testing in predicting success with SCS

Daniel et al calculated an 80% accuracy rate using the MMPI and BDI for predicting success.

Burchiel et al. found that the BDI score and mania scale on the MMPI emerged as predictors. Less helpful in a subsequent study.

Long et al reported a 33% success rate in unscreened patients compared with 70% in screened patients.


Trial TechniquesTrial Techniques

Trial implant Easiest Fastest Remove electrode in office Low prob candidates If multiple choices or procedures

debated If location not suitable for trial

extension Requires reimplant of electrode

at permanent implant

“Permanent Trial” Permanent implant easier Remove electrode in OR If finding therapeutic location 2nd

time will be difficult If implant technique difficult or

invasive If general anes needed for

permanent system


Paddle TrialsPaddle Trials

Lumbar fusion or laminectomy precluding

percutaneous insertion

Inability to access the epidural space

percutaneously

Bony anatomy

Obesity

Prior procedure in the region of the implant

Tumor resection, etc.



Preop imaging is essentialPreop imaging is essential

You would never do any other spine case without adequate preop imaging – DON’T START NOW

Preop imaging makes sure something asymptomatic doesn’t become symptomatic

Aids in counseling patient preop if procedure needs to be altered to deal with anatomic issue


Preop imaging is essentialPreop imaging is essential

Where is the cord???

The cord may not respect the spinal column midline

Paddle may look great on fluoro and not provide adequate coverage


E-mail: E-mail: [email protected]@nmff.org

Thank you for coming!Thank you for coming!

Phone: Phone: 312-695-0495312-695-0495

Documents

Department of Neurosurgery, Feinberg School of Medicine, Northwestern University Spinal Cord Stimulation: Indications and Patient Selection Joshua M