Pain Outcomes Following Modern External Ring Fixation Compared with Internal Fixation for Severe Open Tibial Fractures: A Secondary Analysis of a Prospective Randomized Trial (FIXIT).

Abstract

It is unclear whether postoperative pain differs by treatment type for patients with severe open tibial fractures. We performed a secondary analysis of data from the FIXIT study. Adults with severe open tibial fractures were randomized to undergo definitive modern external ring fixation (n = 122) or internal fixation (n = 132). Primary outcomes were pain intensity and interference at 6 and 12 months, measured by the Brief Pain Inventory. Secondary outcomes were Numeric Pain Rating Scale (NPRS) scores and the incidence of moderate to severe pain. Post hoc subanalysis compared pain in patients with and without pin-site infections and with and without external fixation removal. At 6 months, median pain intensity did not differ significantly between the external fixation group (4.1 [interquartile range (IQR), 2.2 to 5.5]) and the internal fixation group (3.0 [IQR, 1.8 to 5.8]) (p = 0.11); however, patients who underwent external fixation had greater median pain interference (6.0 [IQR, 3.3 to 8.0]) than patients who underwent internal fixation (4.0 [IQR, 1.9 to 7.4]) (p = 0.01). At 12 months, pain intensity, pain interference, and NPRS scores did not differ by treatment type. The overall incidence of moderate to severe pain was 33% at 6 months and 35% at 12 months. At 6 months, pin-site infections were associated with greater pain intensity (p = 0.01) but not greater interference (p = 0.10). At 12 months, the presence of external fixation was associated with greater pain intensity (p = 0.01) and interference (p < 0.01). At 6 months after a severe open tibial fracture, patients treated with modern external ring fixation had greater pain interference than patients treated with internal fixation, partly because of pin-site infections. No differences in pain interference or intensity were seen at 12 months. At 12 months, patients with external fixation in place had greater pain intensity and interference than those whose external fixation had been removed, but this was not the case at 6 months. Approximately one-third of all patients had moderate to severe pain at both time points, highlighting that persistent pain is common, regardless of treatment type. These findings can guide surgeons in choosing ring external fixation or internal fixation for these fractures. Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.