Department of Neurosurgery, Feinberg School of Medicine, Northwestern University Spinal Cord Stimulation: Indications and Patient Selection Joshua M. Rosenow, MD, FACS Associate Professor of Neurosurgery Director, Functional Neurosurgery Northwestern Memorial Hospital

Department of Neurosurgery, Feinberg School of Medicine, Northwestern University Disclosures  Consultant:  Boston Scientific Neuromodulation  Medtronic Navigation

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

Department of Neurosurgery, Feinberg School of Medicine, Northwestern University Indications for Surgery  Compressive lesion  Associated radiculopathy  Demonstrable neurologic deficit  Clear instability / deformity

Department of Neurosurgery, Feinberg School of Medicine, Northwestern University CRPS Diagnostic Criteria

Department of Neurosurgery, Feinberg School of Medicine, Northwestern University Revised 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. Complex Regional Pain Syndrome: Treatment Guidelines. RSDSA press. 2006:1-11.

Department of Neurosurgery, Feinberg School of Medicine, Northwestern University Surgical Contraindications  Thecal sac compression by tumor  Significant spinal deformity  Severe emaciation  Significantly low WBC, plt  Coagulopathy  Ongoing infection  Unsuccessful trial

Department of Neurosurgery, Feinberg School of Medicine, Northwestern University SCS: 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

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

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

Department of Neurosurgery, Feinberg School of Medicine, Northwestern University Other Treatments  Should proceed in parallel  Psychological counseling  Behavioral treatments  Physical therapy and conditioning  Vocational counseling and rehab  Implantables can’t fix everything!

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

Department of Neurosurgery, Feinberg School of Medicine, Northwestern University Pain Psychology  Spine surgery success in the presence of:  Childhood physical or sexual abuse,  Emotional neglect/abuse  Abandonment  Chemically dependent parents: # FactorsSurgical Success 195% 195% % % 3 or more 15% 3 or more 15%  Spine surgery success in the presence of:  Childhood physical or sexual abuse,  Emotional neglect/abuse  Abandonment  Chemically dependent parents: # FactorsSurgical Success 195% 195% % % 3 or more 15% 3 or more 15% (Shofferman et al., 1992)

Department of Neurosurgery, Feinberg School of Medicine, Northwestern University Predictive 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.

Department of Neurosurgery, Feinberg School of Medicine, Northwestern University Trial 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 2 nd time will be difficult  If implant technique difficult or invasive  If general anes needed for permanent system

Department of Neurosurgery, Feinberg School of Medicine, Northwestern University Paddle 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.

Department of Neurosurgery, Feinberg School of Medicine, Northwestern University

Preop 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

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

Department of Neurosurgery, Feinberg School of Medicine, Northwestern University Thank you for coming! Phone: