Readmission Rates, Reasons, and Risk Factors Following Anterior Cervical Fusion for Cervical Spondylosis in Patients Above 65 Years of Age.

STUDY DESIGN: A retrospective database review.

OBJECTIVE: The aim of this study was to determine readmission reasons and rates following primary, elective anterior cervical spinal fusion surgery for cervical spondylosis and determine risk factors predicting increased risk of 30-day readmission in an exclusively elderly population.

SUMMARY OF BACKGROUND DATA: In the United States, there were almost 190,000 cervical spine procedures in 2009. Many cervical spine surgery patients are elderly, a demographic increasingly requiring surgery for degenerative cervical spine pathology. Unfortunately, this patient population is poorly studied, particularly concerning readmission rates.

METHODS: Medicare data from 2005 to 2012 were queried for elderly patients (65-84 years) who underwent primary one to two and ≥three-level anterior cervical spine fusion surgeries for cervical spondylosis. Forty-five thousand two hundred eighty-four patients treated with one to two-level and 12,103 patients with ≥three-level anterior cervical fusion (ACF) were identified and included in two study cohorts. Reasons for and rates of readmission were determined within 30 days, 90 days, and one-year postoperatively. Risk factors for medical, surgical, and all 30-day readmissions were also determined, selecting from various comorbidities, demographics, and surgical variables.

RESULTS: Readmission rates of 1.0% to 1.4%, 2.7% to 3.6%, and 13.2% to 14.1% were observed within 30 days, 90 days, and one year. Within 30 days, over 30% of patients from both study cohorts were readmitted for surgical reasons. Of surgical reasons for 30-day readmission, hematoma/seroma diagnoses were the most frequent (11.4%-15.4% of all readmissions). Male gender, diabetes mellitus, chronic pulmonary disease, obesity, and smoking history were all found to be predictive of all-cause readmissions.

CONCLUSION: Unplanned 30-day readmission rates following primary, elective ACF in elderly patients is low and often due to medical reasons. Frequent surgical reasons for 30-day readmission include hematoma/seroma formation. Male gender and various comorbid diagnoses are significant predictors of all-cause readmissions within 30 days.

LEVEL OF EVIDENCE: 3.