Prophylactic Muscle Flap Closure after Spinal Fusion Improves Outcomes and Reduces Health Care Costs

Spinal degeneration and deformities affect more than 27% of US adults, and $14.1 billion is spent annually on spinal fusion to address these pathologies. Wound closure using local muscle flaps has been associated with reduced complication rates, including infection and reoperation. The high prevalence of degenerative deformities and health care expenditures highlight the need for resource utilization studies to inform decision-makers on best operative practices.

A retrospective review was performed on adult patients who underwent posterior spinal fusion for degenerative or deformity indications at the authors' institution between 2019 and 2022. Patients were stratified by the prophylactic use of muscle flap closure, and outcomes were compared between groups. Costs were applied to consumed resources, and univariate and multivariable regression analyses were performed to measure the impact of muscle flaps on overall costs.

Of 520 included patients, 240 received muscle flap closures. These patients had significantly fewer readmissions (odds ratio [OR], 0.49 [95% CI, 0.29, 0.84]), reoperations (OR, 0.49 [95% CI, 0.26, 0.89]), and hardware failures (OR, 0.09 [95% CI, 0.00, 0.45]), but greater odds of seroma (OR, 5.22 [95% CI, 2.12, 15.7]). They also had shorter hospital stays (5.4 versus 6.5 days [ P = 0.033]), but operative time did not vary by closure type. Multivariable regression revealed that muscle flap closure was associated with a $7152 reduction in overall costs per patient ( P < 0.03).

Muscle flap closure correlates with reduced complication rates and decreased overall costs per patient. These findings support the use of prophylactic muscle flap closure from safety and health economics perspectives.