Breaking the Bundle: Identification of Factors Associated with Higher Costs for Laminectomies in a Bundled Payment Program

Introduction: In 2018, a bundled payment model was introduced in the United States by the Center for Medicare & Medicaid Services (CMS) to improve quality and reduce costs. While hospitals may be rewarded for low costs, they are penalized financially by high costs, or patients who break the bundle. We aimed to determine which factors led to higher costs for patients undergoing laminectomies at our institution in the Bundled Payments for Care Improvement Advanced (BPCIA) model with a specific focus on minimally invasive surgery (MIS) vs. open surgery.

Methods: Patients undergoing non-instrumented laminectomies within BPCIA between 10/1/2018-3/1/2023 were identified at our institution by CPT (current procedural terminology) and DRG (diagnosis-related group) codes. Clinical and financial outcomes data was collected. Univariate and multivariable analyses identified factors associated with higher cost.

Results: We identified 70 laminectomy patients of which 20 (29%) underwent MIS and 50 (71%) underwent open surgery. Financial data showed that 54 patients (77%) were under bundle target price while 16 (23%) cases were over target price.  Although MIS patients had significantly fewer levels decompressed, shorter hospitalization, and less anchor spend than open surgery patients, surgical approach was not a significant predictor of negative financial performance. After controlling for DRG category, sex, smoking status, age, ASA score, BMI, MIS vs. open, and diagnosis, only ASA score and number of ED visits were independently associated with negative financial performance.

Conclusion : In our laminectomy cohort, MIS surgeries led to shorter hospital LOS and reduced anchor spend but performed similarly to open surgery financially in the bundled payment program. Factors independently associated with higher costs were ASA score and number of ED visits.