Increased age and modified fragility index increases risk of short-term complications after anterior cruciate ligament reconstruction surgery.

Background: Large data analysis of anterior cruciate ligament reconstruction (ACLR) short-term complications on age will help surgeons stratify and counsel at-risk patients. The purpose of this study is to assess if older patients are at greater risk for short-term complications after ACLR.

Methods: This retrospective cohort study included patients who underwent elective ACLR with or without concomitant meniscal procedures in the National Surgical Quality Improvement Program from 2005 to 2017. Patients were divided into age groups 16-30, 31-45, and > 45. Modified fragility index-5 (mFI-5), demographics and short-term outcomes were examined with bivariate and multivariate analysis to determine if age was a risk factor for complications.

Results: A total of 23,581 patients (35.4% female) were included in this analysis. Mean age was 32.1 ± 10.8 years. Older patients had higher mFI-5 scores (p < 0.001), shorter operative times (p < 0.001), lower use of only general anesthesia (p < 0.001). The oldest patients had similar rates of complications as the two younger groups. Older age was an independent risk factor for VTE, but decreased risk of prolonged operations. A mFI-5 > 0 increased risk factors for readmission (Odds ratio 2.2, P = 0.006). Infection was the most common cause 30-day readmissions (40/135, 29.6%).

Conclusion: In the early postoperative period, older age is an independent risk factor for VTE and younger age is a significant factor for prolonged surgeries. Having an mFI-5 > 0 increased risk factors for readmission.