Epidemiology and risk factors for fat embolism in isolated lower extremity long bone fractures

Natthida Owattanapanich; Meghan Lewis; Subarna Biswas; Elizabeth R Benjamin; Demetrios Demetriades

doi:10.1007/s00068-024-02516-9

Epidemiology and risk factors for fat embolism in isolated lower extremity long bone fractures

Eur J Trauma Emerg Surg. 2024 Apr 17. doi: 10.1007/s00068-024-02516-9. Online ahead of print.

Authors

Natthida Owattanapanich^{1

2}, Meghan Lewis¹, Subarna Biswas¹, Elizabeth R Benjamin³, Demetrios Demetriades⁴

Affiliations

¹ Division of Trauma and Surgical Critical Care, Los Angeles General Medical Center, University of Southern California, Los Angeles, CA, USA.
² Division of Trauma Surgery, Department of Surgery, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.
³ Department of Surgery, Grady Memorial Hospital, Emory University School of Medicine, Atlanta, GA, USA.
⁴ Division of Trauma and Surgical Critical Care, Los Angeles General Medical Center, University of Southern California, Los Angeles, CA, USA. demetria@usc.edu.

PMID: 38630127
DOI: 10.1007/s00068-024-02516-9

Abstract

Purpose: Fat embolism syndrome (FES) is a serious complication after orthopedic trauma. The aim of this study was to identify risk factors for FES in isolated lower extremity long bone fractures.

Methods: The National Trauma Data Bank "NTDB" study included patients with isolated femoral and tibial fractures. A total of 344 patients with FES were propensity score matched with 981 patients without FES. Multivariate logistical regression was used to identify independent risk factors for FES.

Results: FES was diagnosed in 344 (0.03%) out of the 1,251,143 patients in the study populations. In the two matched groups, the mortality was 7% in the FES group and 1% in the No FES group (p < 0.001). FES was associated with an increased risk of ARDS, VTE, pneumonia, AKI, and stroke. Younger age, femur fractures, obesity, and diabetes mellitus were independent predictors of FES. Early operative fixation (≤ 48 h) was protective against FES.

Conclusion: FES increases mortality by seven times. Young age, obesity, and diabetes mellitus are significant independent risk factors for FES. Early fixation is independently associated with a reduced risk of FES.

Level of evidence: Level III.

Study type: Prognostic study.

Keywords: Fat embolism; Lower extremity fractures; Risk factors.