65. Cervical fusion in frail elderly patients with type II dens fractures: a propensity score matched analysis based on the 5-item modified frailty index

BACKGROUND CONTEXT

Type II dens fractures are a traumatic injury of the second cervical vertebrae that often require surgical fusion to prevent spinal instability and further neurological insult. In elderly patients, clinicians often opt for conservative management over surgery due to an overall higher risk of complications in this population. For patients who do undergo surgery, frailty is often used to evaluate postoperative risk. The Modified Frailty Index 5 (mFI-5) is a concise metric that has been shown to have similar clinical utility as longer scales such as the Charlson Comorbidity Index and mFI-11.

PURPOSE

To evaluate and quantify which complications are more common following fusion for type II dens fractures for elderly patients with a high mFI-5 compared to those with a low mFI-5.

STUDY DESIGN/SETTING

Retrospective cohort database study.

PATIENT SAMPLE

Patients from the American College of Surgeons National Trauma Data Bank (NTDB) from 2017-2021.

OUTCOME MEASURES

The primary outcome measures are mortality and hospital length of stay (LOS). Secondary outcome measures entail hospital complications such as pressure ulcers and deep vein thrombosis and discharge disposition such as routine discharge to home and discharge to skilled nursing.

METHODS

The NTDB was queried from 2017-2021 for all patients with a traumatic type II dens fracture. Patients younger than 65 years, who did not undergo surgical fusion, or who were missing outcome data were excluded. The mFI-5 was calculated based on the presence of COPD, CHF, diabetes, hypertension, or functional impairment, with one point assigned to each. The categories were mFI-5 of 0, 1, or 2+. Propensity score matching was performed using the k-nearest neighbors algorithm based on patient age, sex, race, ethnicity, insurance type, and Glasgow Coma Scale. Patients with mFI-5 of 1 and 2+ were compared with patients with mFI-5 0 using Student's t-tests and Pearson's chi-square tests.

RESULTS

A total of 2278 patients matching the inclusion and exclusion criteria were identified, of which 457 had mFI-5 0, 907 had mFI-5 1, and 914 had mFI-5 2+. Following propensity score matching, 457 patients in each score group were identified. There were no significant post-match differences in outcomes between patients with mFI-5 0 and mFI-5 1. Compared to patients with mFI-5 0, patients with mFI-5 1 had a higher overall complication rate (77.46% vs 54.05%, p<0.01), lower rates of routine discharge to home (16.63% vs 23.41%, p=0.01) and higher rates of discharge to a skilled nursing facility (31.07% vs 23.63%, p=0.01). Patients with mFI-5 2+ similarly had higher complication rates (71.33% vs 54.05%, p<0.01), lower rates of routine discharge to home (9.63% vs 23.41%, p=0.01) and higher rates of discharge to a skilled nursing facility (37.63% vs 23.63%, p=0.01), and additionally had longer LOS (12.19 vs 10.18 days, p<0.01).

CONCLUSIONS

In elderly patients with traumatic type II dens fractures who undergo surgical fusion, both moderate and and high degrees of frailty as indicated by an mFI-5 of 1 and 2+, respectively, are associated with a roughly ∼20% increase in the incidence of postoperative complications as well as greater rates of discharge to skilled nursing facilities. Cervical fusion remains the standard of care for type II dens fractures in elderly patients with low degrees of frailty, but greater care must be taken to individualize care for elderly patients with higher degrees of frailty.

FDA Device/Drug Status

This abstract does not discuss or include any applicable devices or drugs.