Abstract
BACKGROUND: It remains unclear whether insurance as a proxy for socioeconomic status and social determinants of health is associated with functional outcomes after ankle fracture surgery. This study assesses the association between insurance and Patient-Reported Outcomes Measurement Information System (PROMIS) measures of physical function (PF) and pain interference (PI) after ankle fracture surgery. METHODS: All patients who underwent ankle fracture surgery (2016-2021) were reviewed retrospectively. Multiple injuries, open fractures, pilon variants, and nonanatomically reduced fractures were excluded. Final analysis included 190 patients at minimum 1-year follow-up who completed postoperative surveys querying PROMIS and fear of reinjury. Insurance was categorized as "private," "Medicaid," "Medicare," or "worker's compensation." RESULTS: Twenty-one of 190 had Medicaid, 21 of 190 had Medicare, 141 of 190 had private, and 7 of 190 had worker's compensation. Mean clinical follow-up was 32.1 months for Medicaid, 39.2 Medicare, 45.0 private, and 56.3 worker's compensation. Mean PF (P < .01) and PI scores (P < .01), respectively, were 47.7 ± 9.1 and 53.9 ± 8.1 for Medicaid, 47.6 ± 10.6 and 48.9 ± 10.9 Medicare, 53.9 ± 9.3 and 47.1 ± 7.8 private, and 51.3 ± 10.5 and 51.5 ± 10.5 worker's compensation. In adjusted models, compared with private, Medicaid was associated with 6.41 points lower PF (95% CI: -10.69, -2.13; P < .01) and 6.95 points higher PI (95% CI: 3.11, 10.79; P < .001). Worker's compensation and Medicare were not associated with significant differences in PROMIS compared with private (P > .05). Differences in proportion of patients with fear of reinjury were significant (P < .01): fear was highest in Medicaid (52.4%, 11 of 21) and lowest in Medicare (9.5%, 2 of 21). Fear was associated with significantly worse PF (8.45 points lower, 95% CI: -11.62, -5.28; P < .001). CONCLUSION: Medicaid patients report significantly worse PROMIS scores than those with other insurances following ankle fracture surgery. Fear may be a primary driver of worse PF, as a significantly higher proportion of Medicaid patients experience fear, and fear is associated with significantly worse PF. To improve outcomes, fear and worse functional outcomes in Medicaid patients should be addressed. LEVEL OF EVIDENCE: Level III, retrospective comparative study.