The James A. Rand Young Investigator's Award: Battling the Opioid Epidemic with Prospective Pain Threshold Measurement.

BACKGROUND: Responsible analgesic prescribing is paramount in the opioid epidemic era, yet no standardized protocol exists. We aim to (1) quantify and correlate outpatient opioid need after total knee and hip arthroplasties (TKA and THA) with preoperative objective pain pressure thresholds (PPTs) and subjective pain measures and (2) report incidence of nonsurgical opioid prescriptions 6 weeks postoperatively.

METHODS: Prospectively, PPTs were measured using an algometer with a maximum force of 20 pounds in 160 consecutive patients (90 TKA and 70 THA). Two locations were tested: operative joint (medial epicondyle TKA and lateral iliac crest THA) and ipsilateral olecranon for systemic control. Visual Analog Score, Pain Severity Score, Pain Interference Score, and subjective pain threshold were obtained. Six-week outpatient narcotic consumption morphine equivalents recorded and prescriptions crosschecked with the state Controlled Substance Reporting System. Multivariate analysis was performed to evaluate local and/or systemic PPT and subjective measures with narcotic consumption.

RESULTS: Average operative site and systemic PPT was 6.91 and 7.72 pounds force, respectively. Subjective averages: Visual Analog Score 7.14, Pain Severity Score 5.05, Pain Interference Score 5.16, and perceived threshold 6.77. Six-week average outpatient narcotic consumption was 314.9 morphine equivalents or 125 five milligram oxycodones. Twenty percent received opioids from outside providers. Linear regression revealed a negative correlation between operative site PPT (-0.26; P = .047) and systemic PPT (-0.31; P = .021). Subjective pain metrics failed to meet significance.

CONCLUSION: This novel study demonstrated a statistically significant negative correlation between preoperative pain threshold and outpatient narcotic consumption. Twenty percent of patients received opioid prescriptions outside orthopedic providers in the 6 weeks after surgery highlighting the importance of interdisciplinary communication.