Supplementary Appendix This appendix has been provided by the authors to give readers additional information about their work. Supplement to: Friedly JL, Comstock BA, Turner JA, et al. A randomized trial of epidural glucocorticoid injections for spinal stenosis. N Engl J Med 2014;371:11-21. DOI: 10.1056/NEJMoa1313265
Supplementary Web Appendix Table of Contents Table 1: LESS Trial Inclusion and Exclusion Criteria Page 2 Table 2: Additional baseline LESS trial patient and procedural characteristics Page 4 Table 3: Procedure-related adverse events (0 to 6 week assessment) and Page 5 pre-specified secondary analysis of cortisol suppression by treatment group
Table 1: Inclusion and Exclusion Criteria Inclusion Criteria Pain in the low back, buttock, and/or lower extremity (rating of average pain in past week>4 on 0-10 scale) with standing, walking and/or spinal extension (buttock/leg>back pain) Roland-Morris Disability Questionnaire (modified to specify back or leg pain-related problems) score of at least 7 Mild-moderate-severe lumbar central canal spinal stenosis identified by MRI or CT according to the criteria of Boden et al.* Lower extremity symptoms consistent with neurogenic claudication Able to read English and complete the assessment instruments Age 50 years or older Exclusion Criteria Cognitive impairment that renders the patient unable to give informed consent or provide accurate data Fibromyalgia diagnosis, chronic widespread pain, lower extremity amputation, Parkinson s, head injury, stroke, other neurologic conditions Severe vascular, pulmonary or coronary artery disease that limits ambulation including recent myocardial infarction (within the last 6 months) Spinal instability requiring surgery Severe osteoporosis as defined by multiple compression fractures or a fracture at the same level as the stenosis Metastatic cancer Excessive alcohol consumption or evidence of non-prescribed or illegal drug use as determined by the two item conjoint screen (TICS) screening questionnaire (1 or more positive answer) Possible pregnancy or other condition that precludes the use of fluoroscopy Concordant pain with internal rotation of the hip (or known hip joint pathology) Active local or systemic infection Allergy to local anesthetic, steroid or contrast 2
*Boden SD. The use of radiographic imaging studies in the evaluation of patients who have degenerative disorders of the lumbar spine. The Journal of bone and joint surgery American volume 1996;78:114-24. Brown RL, Leonard T, Saunders LA, Papasouliotis O. A two-item conjoint screen for alcohol and other drug problems. J Am Board Fam Pract. 2001 Mar-Apr;14(2):95-106. 3
Table 2. Additional baseline LESS trial patient and procedural characteristics Characteristic Lidocaine (N=200) Corticosteroid + Lidocaine (N=200) Study recruitment site - no. (%) Henry Ford (2 sites) 62 (31.0%) 60 (30.0%) Harvard (4 sites) 60 (30.0%) 63 (31.5%) Kaiser (3 sites) 36 (18.0%) 33 (16.5%) Other (6 sites) 42 (21.0%) 44 (22.0%) Physician rated severity of stenosis - no. (%) Mild 43 (21.5%) 43 (21.5%) Moderate 96 (48.0%) 100 (50.0%) Severe 61 (30.5%) 57 (28.5%) Steroid preparation* - no. (%) Celestone 60 (30.0%) 62 (31.0%) Depomedrol 58 (29.0%) 61 (30.5%) Dexamethasone 34 (17.0%) 34 (17.0%) Kenalog 48 (24.0%) 43 (21.5%) Transforaminal approach - no. (%) (n=61) (n=57) Bilateral injections 31 (50.8%) 24 (42.1%) Multilevel 19 (31.1%) 14 (24.6%) * Steroid preparation in the discard syringe of the lidocaine arm. 4
Table 3 Adverse events (0 to 6 week assessment) determined by investigators to be likely treatmentrelated and pre-specified secondary analysis of cortisol suppression by treatment group Corticosteroid Lidocaine (n=200) + Lidocaine (n=200) P-value Patients with at least 1 procedure related event no. (%)* 19 (9.5%) 30 (15.0%) 0.09 Total adverse events no. (no. / pt.) 22 (0.11) 34 (0.17) 0.12 Symptoms of procedure related events no. Excessive pain 6 4 Headache 2 7 Fever / infection 2 7 Dizziness / lightheadedness 3 4 Numbness / tingling 4 4 Cardiovascular / lung problems 1 3 Falls 2 2 Facial flushing 0 3 Skin irritation 4 2 Leg swelling 1 1 Dural puncture 1 1 Other 1 1 Procedure related serious adverse events Hospitalization / surgery 1 0 AM cortisol levels* no. (%) Three weeks (n=148, 158) > 50% 10 (6.8%) 32 (20.2%) <0.001 > 90% 0 (0%) 5 (3.2%) 0.06 Six weeks (n=144, 146) > 50% 6 (4.2%) 18 (12.3%) 0.02 > 90% 0 (0%) 0 (0%) - 5
* Statistical significance was assessed using a logistic regression model adjusted for recruitment site (4 levels) and treatment group assignment. While the study protocol included a blood draw at 3 and 6 weeks regardless of whether or not an injection was scheduled, some participants chose not to come in for blood draws, particularly those who were not scheduled for a repeat injection at those time points. Therefore, the total sample size for this analysis is less than the overall clinical trial sample size. Three week cortisol levels > 90% were compared using Fisher s exact test. Our preplanned analysis plan included categorizing patients by percentage suppression from baseline (to represent moderate suppression >50% and nearly complete suppression >90%). We reported a more clinically relevant analysis in the print version, although both methods produced similar results. Statistical significance assessed using a Poisson regression model with robust standard errors adjusted for recruitment site (4 levels) and treatment group assignment. 6