PNS FOR BACK PAIN IMPROVING PATIENT OUTCOMES

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1 PNS FOR BACK PAIN IMPROVING PATIENT OUTCOMES New Level-1 evidence The SubQStim Study The Focus SM workflow A recommended and standardised approach for applying PNS based on clinical data

2 BACK PAIN REDUCE BACK PAIN WITH PNS An estimated 95 million Europeans suffer from chronic pain, or around one in five adults 1,2 Patients with new or persistent pain following spinal corrective surgery may be diagnosed with failed back surgery syndrome (FBSS). It is difficult to estimate the prevalence of FBSS accurately; its frequency in the general population can reach up to 2, cases per 1,. Patients with FBSS may suffer from pain caused by more than one aetiology; thus, it is commonly treated by medication and interventional therapy. 4 However, it can be difficult to treat with conventional medical management alone. 5 A systematic review and meta-analysis revealed that FBBS patients experience substantially lower health-related quality of life (HRQoL) compared with the general population but also with other chronic diseases. 3, 6 PNS provides better pain relief vs. optimised medical management (OMM) alone in FBSS The SubQStim study is the first randomised controlled trial (RCT) comparing SQS+OMM to OMM alone in patients with FBSS. In this prospective, multicentre RCT, 116 patients with predominant to pure back pain were randomised to OMM with or without PNS (SQS). 8 At 9 months, significantly more subjects in the SQS group (17 of 3; 56.7%) achieved at least 5% back pain relief than in the OMM-alone group (1 of 35; 2.9%) (p<.1). 8 Subjects receiving SQS experienced a clinically and statistically significant reduction in back pain intensity compared to baseline in all analyses. 8 9-MONTH RESPONDER RATE ( 5% REDUCTION IN BACK PAIN INTENSITY) PER TREATMENT N =65 It is difficult to estimate the prevalence of FBSS accurately; its frequency in the general population can reach up to 2, cases per 1, 3 For patients with inadequate pain relief or intolerable side effects from medication, subcutaneous peripheral nerve stimulation (PNS) may be an option. PNS is a therapy where electrical stimulation is delivered to nerves within the subcutaneous tissue layer of the posterior trunk to modulate the transmission of pain signals to the brain. PNS has gone by many names, such as subcutaneous nerve stimulation (SQS) and peripheral nerve field stimulation (PNFS). % OF SUBJECTS % 97.1% 56.7% 2.9% TREATMENT RESPONDER NON-RESPONDER

3 IMPROVE FUNCTION WITH PNS THE SAFETY OF PNS MEAN BACK PAIN INTENSITY OVER TIME BY TREATMENT GROUPS ITT (N=116), MEANS + SEM MEAN BACK PAIN INTENSITY [VAS] BASELINE MONTH 3 MONTH 6 VISIT PNS improves function MONTH 9 In the SubQStim study, subjects receiving SQS in addition to OMM achieved significant improvement from baseline in functional disability (as measured by the Oswestry Disability Index (ODI)) compared to those receiving OMM alone (p<.1). 8 Technical complications of the PNS system are low. In the SubQStim study, most adverse events (67.2%) were of an unrelated aetiology or due to medication (18.2%). 8 Across all 8 implanted subjects, a total of four (5.%) device or implant related-infections occurred, two (2.5%) lead dislocation/migrations, and one (1.3%) lead fracture in situ. With leads placed in the subcutaneous tissue layer, PNS avoids possible events related to epidural lead placement such as epidural haematoma or seroma, cerebral spinal fluid leakage and paralysis. KEY TECHNICAL COMPLICATIONS 1.3% 2.5% Lead fracture or damage in situ (n=1) device/lead connection issues (n=2) FUNCTIONAL DISABILITY (ODI) MEAN & 95% CI, PER TREATMENT N=65 2.5% % ODI SCORE (%) lead migration or dislocation (n=2) cases of erosion BASELINE MONTH 3 MONTH 6 MONTH 9 VISIT

4 The Focus SM workflow PNS BEST PRACTICE GUIDANCE IDEAL PATIENT PRESENTS WITH: Defined, focal back pain located below the rib cage and above the iliac crest Worst pain about the size of 1 2 business cards (1 card = 55 mm x 85 mm) Significant back pain (eg, 5 on a 1 scale) No or insignificant leg pain that is sufficiently managed conservatively Disability on ODI no worse than a category score of severe No severe or untreated depression At least a moderate level of quality of life The Focus SM workflow is a recommended and standardized approach for physicians interested in applying subcutaneous PNS in patients with chronic, intractable back pain. It is based on analyses of 3 clinical studies IMPLANT PROCEDURE 1 2 percutaneous leads i subcutaneously on a cranial-caudal axis in the centre of maximal pain Avoid lead placement directly in areas of allodynia ii Ensure optimal paraesthesia coverage The SubQStim Study Austrian PNFS Registry Dutch SubQ Study and review and consensus by a panel of 9 expert physician advisors from 6 countries. PROGRAMMING Start trial with one programme per lead using one anode and one cathode 4 Hz and 21 μs Soft start/stop at 4 sec Adjust amplitude to comfort Allow a sufficient trial period duration to evaluate outcomes. Higher patient usage of PNS therapy correlated to better outcomes iii FOCUS ON PATIENT SELECTION IMPLANT PROCEDURE PROGRAMMING To learn more, speak to your local Medtronic sales representative. i Select lead for broadest paraesthesia coverage. ii Consider implanting leads directly outside/bracketing the area. iii Results from post-hoc analyses of the SubQStim Study 8, PNFS Prospective Study 9, SubQ study 1 and expert clinician review and input from the PNS Advisory Board. The Focus SM workflow is guidance only and physicians should use their medical judgment and product labelling to optimise therapy for individual patients, which may require discontinuation or modification of the workflow.

5 See the device manual for detailed information regarding the instructions for use, the implant procedure, indications, contraindications, warnings, precautions and potential adverse events. For further information, contact your local Medtronic representative and/or consult the Medtronic website at 1. Langley PC. The prevalence, correlates and treatment of pain in the European Union. Curr Med Res Opin. 211;27(2): Breivik H. Survey of chronic pain in Europe: prevalence, impact on daily life, and treatment. Eur J Pain. 26;1(4): Taylor RS, Taylor RJ. The economic impact of failed back surgery syndrome. British Journal of Pain 212;6(4) Chan CW, Peng P. Failed back surgery syndrome. Pain Med. 211;12: Desai MJ, Nava A, Rigoard P, et al. Optimal medical, rehabilitation and behavioral management in the setting of failed back surgery syndrome. Neurochirurgie. 215;61(Suppl1):S66 S Doth AH, Hansson PT, Jensen MP, Taylor RS. The burden of neuropathic pain: a systematic review and meta-analysis of health utilities. Pain. 21;149(2): SubQStim: A Post-market Study of Subcutaneous Nerve Stimulation in Failed Back Surgery Syndrome (FBSS) Patients. Available at SubQStim Study # Final Clinical Study Report v. 2., Trial Master File. Publication pending. 8. Kloimstein H, Likar R, Kern M, et al. Peripheral Nerve Field Stimulation (PNFS) in Chronic Low Back Pain: A Prospective Multicenter Study. Neuromodulation. 213;17(2): Gorp EJ, Teernstra OP, Gültuna I, et al. Subcutaneous Stimulation as ADD-ON Therapy to Spinal Cord Stimulation Is Effective in Treating Low Back Pain in Patients with Failed Back Surgery Syndrome: A Multicenter Randomized Controlled Trial. Neuromodulation. 216;19(2): Europe Medtronic International Trading Sarl Route du Molliau 31 Case postale 1131 Tolochenaz Switzerland Tel: +41 () Fax: +41 () United Kingdom Medtronic Limited Building 9 Croxley Park Hatters Lane Watford, Hertfordshire WD18 8WW Tel: +44 () Fax: +44 () Ireland Medtronic Ireland Ltd. Block G, First Floor Cherrywood Business Park Loughlinstown, Co Dublin 18 Ireland Tel: UC EE 218 Medtronic. All Rights Reserved. Printed in Europe. medtronic.eu medtronic.co.uk medtronic.co.uk