Single-Stage Surgical Treatment of Multi-ligament Knee Injuries Results in Lower Cost and Fewer Complications and Unplanned Reoperations Compared With Staged Treatment

PURPOSE: To compare complications, unplanned reoperations, and costs between single-stage and 2-stage treatment of multi-ligament knee injuries. METHODS: The MarketScan database was queried (2007-2016), identifying patients undergoing surgery for a multi-ligament knee injury. The single-stage cohort was defined as having at least 2 Current Procedural Terminology codes for ligament reconstruction at the index procedure without a Current Procedural Terminology code for ligament reconstruction appearing in the database for the following 12 months. The 2-stage cohort was defined as undergoing multiple ligament reconstruction procedures within a 12-month period with subsequent ligament procedure codes that differed from the index ligament reconstruction codes. Propensity score matching was performed using a greedy nearest-neighbor algorithm to match specific injury patterns between the 2 cohorts. Baseline demographic characteristics, medical comorbidities, and the Charlson Comorbidity Index were recorded. Complications, unplanned reoperations, and total health care expenditures were recorded for up to 5-year follow-up. Two-sample t tests, χ(2) tests, and Fisher exact tests were used with an α level of .05 set as significant. RESULTS: We identified 1,150 patients who underwent surgery for multi-ligament knee injuries (1,080 with single-stage approach and 270 with 2-stage approach). No significant differences in baseline characteristics or medical comorbidities were found between the cohorts. After propensity score matching, the single-stage group had fewer complications at 30, 90, 180, and 365 days (P < .05). Two-stage treatment increased the risk of reoperation at 1 year (5.5 times) and 2 years (4.9 times) after the index procedure. Health care expenditures were lower in the first 9 months for the staged cohort, but from 9 months ($31,210 vs $22,252, P < .0001) through 5 years, total costs were higher in this group. CONCLUSIONS: Single-stage surgical treatment of multi-ligament knee injuries results in fewer complications and reoperations and lower total costs compared with 2-stage treatment, even after controlling for the number and combination of ligaments injured. LEVEL OF EVIDENCE: Level III, retrospective cohort study.