Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2023 Apr 1;37(4):175-180.
doi: 10.1097/BOT.0000000000002553.

Risk Factors for Nonunion of Distal Femur Fractures

Affiliations

Risk Factors for Nonunion of Distal Femur Fractures

Ryan Cone et al. J Orthop Trauma. .

Abstract

Objectives: To determine patient, fracture, and construct related risk factors associated with nonunion of distal femur fractures.

Design: Retrospective cohort study.

Setting: Academic Level I trauma center.

Participants: Patients 18 years and older presenting with OTA/AO 33A and 33C distal femur fractures from 2004 to 2020. A minimum follow-up of 6 months was required for inclusion. OTA/AO 33B and periprosthetic fractures were excluded, 438 patients met inclusion criteria for the study.

Main outcomes: The primary outcome of the study was fracture nonunion defined as a return to the OR for management of inadequate bony healing. Patient demographics, comorbidities, injury characteristics, fixation type, and construct variables were assessed for association with distal femur fracture nonunion. Secondary outcomes include conversion to total knee arthroplasty, surgical site infection, and other reoperation.

Results: The overall nonunion rate was 13.8% (61/438). The nonunion group was compared directly with the fracture union group for statistical analysis. There were no differences in age, sex, mechanism of injury, Injury Severity Score, and time to surgery between the groups. Lateral locked plating characteristics including length of plate, plate metallurgy, screw density, and working length were not significantly different between groups. Increased body mass index [odds ratio (OR), 1.05], chronic anemia (OR, 5.4), open fracture (OR, 3.74), and segmental bone loss (OR, 2.99) were independently associated with nonunion. Conversion to total knee arthroplasty (TKA) ( P = 0.005) and surgical site infection ( P < 0001) were significantly more common in the nonunion group.

Conclusion: Segmental bone loss, open fractures, chronic anemia, and increasing body mass index are significant risk factors in the occurrence of distal femoral nonunion. Lateral locked plating characteristics did not seem to affect nonunion rates. Further investigation into the prevention of nonunion should focus on fracture fixation constructs and infection prevention.

Level of evidence: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

PubMed Disclaimer

Conflict of interest statement

The authors report no conflict of interest.

References

    1. Khan AM, Tang QO, Spicer D. The epidemiology of adult distal femoral shaft fractures in a central london major trauma centre over five years. Open Orthop J. 2017;11:1277–1291.
    1. Bonafede M, Espindle D, Bower AG. The direct and indirect costs of long bone fractures in a working age US population. J Med Econ. 2013;16:169–178.
    1. Brinker MR, Trivedi A, OʼConnor DP. Debilitating effects of femoral nonunion on health-related quality of life. J Orthop Trauma. 2017;31:e37–e42.
    1. Rodriguez EK, Boulton C, Weaver MJ, et al. Predictive factors of distal femoral fracture nonunion after lateral locked plating: a retrospective multicenter case-control study of 283 fractures. Injury. 2014;45:554–559.
    1. Rodriguez EK, Zurakowski D, Herder L, et al. Mechanical construct characteristics predisposing to non-union after locked lateral plating of distal femur fractures. J Orthop Trauma. 2016;30:403–408.