Postoperative pain score does not correlate with injury severity in isolated tibial plateau fractures.

Abstract

Appropriate management of acute postoperative pain is critical for patient care and practice management. The purpose of this study was to determine whether postoperative pain score correlates with injury severity in tibial plateau fractures. A retrospective review of prospectively collected data was completed at a single academic level one trauma center. All adult patients treated operatively for tibial plateau fractures who did not have concomitant injuries, previous injury to the ipsilateral tibia or knee joint, compartment syndrome, inadequate follow-up, or perioperative regional anesthesia were included (n = 88). The patients were split into groups based on the AO/OTA fracture classification (B-type vs C-type), energy mechanism, number of surgical approaches, need for temporizing external fixation, and operative time as a proxy for injury severity. The primary outcome measure was the visual analog scale (VAS) pain score (average in the first 24h, highest in the first 24h, two- and six-week postoperative appointments). Psychosocial and comorbid factors that may affect pain were studied and controlled for (history of diabetes, neuropathy, anxiety, depression, PTSD, and previous opioid prescription). Additionally, opioid use in the postoperative period was studied and controlled for (morphine milligram equivalents (MME) administered in the first 24h, discharge MME/day, total discharge MME, and opioid refills). VAS scores were similar between groups at each time point except the two-week postoperative time point. At the two-week postoperative time point, the absolute difference between the groups was 1.3. The groups were significantly different in several injury and surgical variables as expected, but were similar in all demographic, comorbid, and postoperative opioid factors. There was no clinical difference in postoperative pain between AO/OTA 41B and 41C tibial plateau fractures. This supports the idea of providers uncoupling nociception and pain in postoperative patients. Providers should consider minimizing extended opioid use, even in more severe injuries.