ePoster #706 - ISHA Annual Scientific Meeting 2016

Pre-Operative Opioid Usage Predicts Increased Opioid Usage after Hip Arthroscopy for Femoroacetabular Impingement: Evidence to Align Hip Arthroscopy Practice with AAOS Opioid Use, Misuse, and Abuse Information Statement

Daniel Cunningham, BS, Durham, NC UNITED STATES
Brian D. Lewis, MD, Raleigj, NC UNITED STATES
Carolyn Hutyra, BS, Durham, NC UNITED STATES
Shane J. Nho, MD, MS, Chicago, IL UNITED STATES
Steven Olson, MD, Durham, NC UNITED STATES
Richard C. Mather, MD, MBA, Durham, NC UNITED STATES

Duke University School of Medicine, Durham, NC, UNITED STATES

FDA Status Not Applicable

Summary: Compared with patients not reporting pre-operative opioid usage, patients who reported this risk factor before hip arthroscopy for symptomatic femoroacetabular impingement used 47 and 74 more opioid pills during the first 2 weeks and 6 weeks post-operative, respectively, and also rarely achieved a day without opioid usage before their first post-operative visit.

Background: The AAOS Information Statement on Opioid Use, Misuse, and Abuse in Orthopaedic Practice advocates for standardized opioid protocols for all orthopaedic settings. Additionally, the statement supports using predictive metrics to identify patients at risk for opioid use and abuse. Although the number of hip arthroscopies performed by ABOS members in the US has increased 18-fold between 1999 and 2009, there are currently no evidence-based guidelines for opioid usage after hip arthroscopy for symptomatic femoroacetabular impingement (FAI).

Methods: Patients 18 years of age or older scheduled to undergo hip arthroscopy for symptomatic FAI with either of 2 hip preservation surgeons at an academic, tertiary care center were approached to consider participating in this IRB-approved study. Consented subjects answered questions regarding pre-operative pain, function, and psychological status including opioid and anti-inflammatory medication usage, gender, the International Hip Outcome Tool (iHOT-12), visual analog scale (VAS) pain, Pain Catastrophizing Scale (PCS), and abbreviated Patient Health Questionnaire (PHQ-8). After surgery, patients recorded daily opioid usage up to the first post-operative visit in a study-provided diary. At the 2-week and 6-week post-operative visits, pain medication usage was measured through pill counting. Since opioid usage followed an exponential distribution, univariate effects of pre-operative predictors on 2-week and 6-week pain medication usage outcomes were calculated using a generalized linear model with a reciprocal link function. Predictors having univariate p-values less than 0.15 were incorporated into multivariable generalized linear models also using a reciprocal link function in JMP Pro Version 12.0.1. Using a similar analytic strategy, ordinal logistic regression was employed to evaluate predictors affecting timing of first day with no opioid usage from patient diaries. Predictors in multivariable models with p-value less than 0.05 are reported as significant below.

Results: In a complete case analysis of 40 diaries, 39 completed 2-week pill-counts, and 26 completed 6-week pill-counts, the median patient used 10 (3,31) [median (Q1,Q3)] opioid pills over the first two weeks and 10 (2,30) opioid pills over the first 6 weeks. Pre-operative opioid usage significantly correlated with all 3 outcomes: 2 and 6-week total opioid usage and delay to first day using no opioids. Patients with pre-operative opioid usage took 54 (43,59) and 80 (70, 91) pills by 2 and 6 weeks, respectively while patients without pre-operative opioid usage took 7 (1,18) and 6 (1,21) pills by 2 and 6 weeks, respectively. 83% of patients with pre-operative opioid usage failed to achieve a single day without opioid usage between surgery and their first post-operative visit compared to only 9% of patients without pre-operative opioid usage.

Discussion: Establishing evidence-based guidelines for opioid prescription patterns is critical. This is the first study in FAI treatment to correlate pre-operative predictive factors to post-operative pain medication usage. Patients not using opioids pre-operatively use only 6 pills by 6 weeks compared to 80 pills for patients with pre-operative usage. Measurement of this binary risk factor can likely be implemented without substantial increased clinical time for patient or provider and may guide orthopedists to refer select patients for pre-operative pain regimen optimization.