Risk Factors for Increased Consumption of Narcotics After Hip Arthroscopy

A Prospective, Randomized Control Trial

Ryan S. Selley, MD; Matthew J. Hartwell, MD; Bejan A. Alvandi, MD; Michael A. Terry, MD; Vehniah K. Tjong, MD


J Am Acad Orthop Surg. 2021;29(12):527-536. 

In This Article


Institutional review board approval was obtained for this study. The study design was a prospective, surgeon-blinded, randomized control trial (ClinicalTrials.gov: NCT04169113). Patients who were scheduled to undergo hip arthroscopy for femoroacetabular impingement (FAI) with an associated labral tear by two fellowship-trained surgeons at a single urban academic institution were enrolled after they provided informed consent preoperatively. Inclusion criteria were all patients with the above diagnosis aged ≥18 years and the ability to read and speak English. Excluded were patients with concomitant periacetabular osteotomy, revision surgery, oncologic surgery, another indication for narcotic use, infection, inability to consent, and age <18 years.

All eligible patients completed a preoperative demographic questionnaire designed to obtain the following information: age, sex, height, weight, smoking status, employment status, worker's compensation injury, current sports participation, current narcotic use, and personal or family history of illicit substance abuse. Patients also filled out patient-reported outcome measurements including the International Hip Outcome Tool (iHOT-12),[13] Numeric Pain Rating Scale,[14] and Pain Catastrophizing Scale[15] before surgery. Independent of the above responses, patients were randomized into two groups via block randomization by the research staff. Patients were prescribed either 30 or 60 hydrocodone-acetaminophen 10 to 325 mg tablets on a PRN basis, the equivalent of prescribing 300 morphine milligram equivalents (MMEs) or 600 MME. A multimodal approach to pain control was used, which included postoperative prescriptions for naproxen 500 mg BID and aspirin 325 mg BID scheduled. Preoperatively, on the day of surgery, patients received a single dose of celecoxib 400 mg and acetaminophen 1,000 mg.[16] Intraoperatively, patients received an intra-articular injection of morphine 10 mg and clonidine 100 μg at the conclusion of the procedure.[17] The surgeon was blinded to the amount prescribed. After the procedure, patients were subsequently called at 24 hours, 48 hours, and between 7 and 14 days postoperatively and asked the total number of opiate tablets consumed, the day they stopped taking opioid tablets, how many tablets were left over, and any notable adverse effects. The number of tablets left over was asked to confirm the correct number consumed and account for any misappropriation of tablets if present. If patients were still taking narcotic pain medication at that point, a final follow-up call was placed at 21 days postoperatively. Further chart review was performed to assess for refill requests. The full study design is outlined in Figure 1. Patient-reported outcomes were not repeated postoperatively aside from the above-collected information.

Figure 1.

Study design and postoperative pain regimen. iHOT-12 = International Hip Outcome Tool, NPRS = Numeric Pain Rating Scale, PCS = Pain Catastrophizing Scale.

A total of 111 patients were initially enrolled and randomized, 59 in the 30-tablet group and 52 in the 60-tablet group. Five patients in each group were lost to follow-up. One patient in the 30-tablet group consumed all the opioids by postoperative day 3 and requested to be withdrawn from the study. Final analysis included 53 patients in the 30-tablet group and 47 patients in the 60-tablet group (Figure 2). A power analysis on hip arthroscopy opioid use was not possible because of a lack of published data at the time of institutional review board submission. A power analysis using previous opioid studies in anterior cruciate ligament reconstruction patients was performed, with the assumption that it would be the closest corollary as anterior cruciate ligament reconstruction involves a similar combination of soft tissue and bony work. Studies published before the onset of this trial found that patients took an average of 28 to 38 tablets of either oxycodone or hydrocodone after anterior cruciate ligament reconstruction. It was determined that reducing the number of opioids consumed by half would represent a clinically meaningful reduction in opioid utilization. Therefore, using the reported SDs from the aforementioned studies, a mean of 14 tablets in the 30-tablet group, with an alpha value of 0.05, and power of 90% indicate that at least 31 patients per group would be needed. A post hoc analysis was also performed, to achieve a 50% reduction in tablets used from the 60- to 30-tablet group with 90% power and alpha of 0.05 this study would have needed 149 patients in each group to detect a difference if one existed. The study was concluded on enrollment of 100 patients with follow-up data as it was apparent that 60 tablets was excessive to prescribe given the low number of tablets patients were using.

Figure 2.

CONSORT diagram.

Collected data were analyzed, with the primary outcome being the average number of tablets used between groups. Secondary outcome measurements analyzed the total number of pills remaining, number of days opioids were required, and postoperative Numeric Pain Rating Scale scores at 2 hours, 24 hours, 48 hours, 7 days, and 21 days. Patient baseline characteristics, known predictors of opioid abuse,[18] and surgical information are reported as mean ± SD for continuous variables and percentages for categoric data. A Shapiro-Wilk test was used to test for normality of distribution. Continuous variables were compared using Student t-tests for parametric data, and Mann-Whitney U tests were used for nonparametric data; categoric data were compared using Pearson chi square tests and Fisher exact tests as appropriate. P < 0.05 (two-tailed) was considered significant. Risk factors for increased opioid use after surgery were assessed by performing univariate and multivariate analyses, treating tablets used after surgery as a continuous variable. All independent variables with P < 0.1 were included in the multivariate analysis. All statistical analyses were performed using SPSS (Version 23).