AAPM Abstract Roundup (Part 1)

Abstract #100Safety and Efficacy of Topical Diclofenac Sodium 1% Gel in Seniors and Younger Patients with Hand OsteoarthritisAuthors: Altman R, MD, Gold, M, Wieman M

Purpose: The efficacy and safety of diclofenac sodium 1% gel (DSG) was assessed in patients aged <65 and ≥65 years with hand osteoarthritis (OA).

Results: Patients randomized to DSG (n=198) had improvements relative to baseline at weeks 4 and 6, respectively, in OA pain intensity (42%, 46%), total AUSCAN score (35%, 38%), and GRD (36%, 40%). These improvements were significantly superior to those of patients randomized to placebo (n=187) for OA pain intensity and total AUSCAN score (P≤0.02) at weeks 4 and 6 but for GRD only at week 6 (P=0.02). Differences in efficacy (DSG versus placebo) between patients aged <65 years (DSG n=109, placebo n=100) versus ≥65 years (DSG n=89, placebo n=87) were not statistically significant. Application-site reactions were more common with DSG versus placebo for patients aged <65 years (4% versus 1%) and 65 years (5% versus 3%). No gastrointestinal bleeding or serious treatment-related AEs occurred.

Funding: Endo Pharmaceuticals Inc., Chadds Ford, PA.

Abstract #101Maintenance of Effect of Duloxetine in Patients with Chronic Low Back PainAuthors: Backonja M, Skljarevski V, Zhang S, et al

Purpose: To assess the maintenance of effect of duloxetine in treatment of chronic low back pain (CLBP).

Results: The results demonstrated duloxetine effect on pain reduction was not only maintained (upper bound = -0.45) during the extension, but further significant pain reduction (within-group) was observed. Significant within-group improvements in QOL, RDQ, CGI-S, and BPI severity and interference ratings were observed for patients entering the extension phase. Duloxetine was well tolerated with safety findings similar to those from earlier duloxetine trials. Conclusions: In this study, the analgesic effect of

duloxetine in patients with CLBP was maintained at least 41 weeks.

Funding: Funded by Eli Lilly and Company

Abstract #102MIS Non-Instrumented Facet Arthrodesis for Treatment of Low Back Pain - A Pilot Study at 1 YearAuthors: Bennett D, Hagen J

Purpose: This pilot study is evaluating a minimally invasive surgery (MIS) facet arthrodesis in subjects with low back pain who have had previous success with thermal radiofrequency to show reduced pain, increased function, and reduction in narcotics and radiographic fusion.

Results: Pain was reduced (VAS) from 79 (SD 8.48) to 23 (SD 12.9), function was improved (ODI) from 33.46 (SD 5.04) to 8.32 (SD 5.17). Of 102 grafts at 51 levels, only 4 graft dislodgements occurred—one subject elected to undergo instrumented fusion; most subjects significantly reduced narcotics.

Abstract #103Durability of Paresthesia Coverage in Spinal Cord StimulationAuthors: Bradley K, Yu C, Yang T, et al

Purpose: Paresthesia concordance is necessary for pain relief in spinal cord stimulation, but maintenance of paresthesia coverage is rarely reported. To investigate durability of paresthesia coverage over time, we prospectively collected patient-reported paresthesia coverage of pain and satisfaction with coverage data over a 1-year period.

Results: Thirteen subjects completed assessments for at least 3 follow-up visits (mean follow-up: 52±11 weeks). Over 52 weeks, mean patient-reported paresthesia coverage of pain was 64±30% and mean patient satisfaction with coverage was 0.4±1.3 points. Durability through time (definition: mean standard deviation in within-subject values between follow-up visits) was 19.9±12.2% for paresthesia coverage of pain and 1.1±0.3 points for patient satisfaction, corresponding to roughly 18% of the satisfaction scale. Durability of paresthesia over 1 year was statistically significant. Durability of paresthesia coverage and durability of patient satisfaction with paresthesia coverage were both estimated at around 80%.

Funding: Study sponsored by Boston Scientific Neuromodulation

Abstract #109Milnacipran 100 mg/day in the Treatment of Fibromyalgia: A Randomized, Double-blind, Placebo-controlled TrialAuthors: Datta A, Lesley A, Gendreau R, et al

Introduction: Milnacipran has previously demonstrated efficacy in fibromyalgia (FM) with doses up to 200 mg/day. This new trial evaluates the efficacy and tolerability of milnacipran 100 mg/day for the management of FM.

Results: At 3 months, a significantly greater proportion of patients treated with milnacipran 100 mg/day met 2- and 3-measure composite responder criteria than placebo (P<.001, both measures; BOCF). Milnacipran-treated patients demonstrated significantly greater improvements from baseline than placebo on a number of additional endpoints (LOCF), including 24-hour recall pain, PGIC, SF-36 PCS, BPI average pain severity, FIQ total (all measures, P<.001), and MFI total (P=.036). Milnacipran was well-tolerated by the majority of patients; nausea was the most common adverse event (20.8%, placebo; 36.6%, milnacipran).

Funding: Study was supported by Forest Laboratories, Inc. and Cypress Bioscience, Inc.