BACKGROUND CONTEXT The fundamental shift from volume to value in health care delivery has seen an increase in alternative payment models such as the Bundled Payments for Care Improvement Initiative (BPCI). The Centers for Medicaid and Medicare Services (CMS) implemented the most recent iteration of BPCI, BPCI Advanced (A) in 2018. BPCI-A is a retrospective payment model that provides a lump payment for a 90-day episode of care. BPCI-A for spine includes the diagnosis related groups (DRG) for cervical spine surgery (C_PSF, 471,472,473), lumbar spinal fusion (L_PSF, 459-460), and lumbar decompression/discectomy (Decomp, 518, 519, 520). In preparation for BPCI participation, our center instituted care delivery improvements based on CMS evaluation of our historical data that was utilized to determine eligibility for participation and from patient input. Care improvements included a weekly multidisciplinary stakeholder meeting and assignment of a full-time nurse care coordinator to cover BPCI-A patients from both the orthopedic/neurosurgery service lines. PURPOSE The purpose of the study was to determine whether patient outcomes, including length of stay, readmission rates and ED visits, changed following participation in BPCI compared with historical data. STUDY DESIGN/SETTING A retrospective and prospective claims data review of all Medicare patients into specified spine surgery DRGs. PATIENT SAMPLE This study included 358 retrospective patients, 63 prospective patients with minimum of 6 months of follow-up. OUTCOME MEASURES Emergency department (ED) utilization and readmission rates. METHODS As part of the BPCI-A application process, retrospective patient data from January 1, 2013 through November 30, 2017 were provided to CMS to determine bundle-specific target prices. BPCI-A began on October 1, 2019 and analyses included those patients whose participation ended by September 30, 2019 (BPCI group, n=63) and those included in the CMS historical review (pre-BPCI group, n=358). Patient and surgery characteristics including age, body mass index (BMI), gender, race, age-adjusted Charlson Comorbidity Index (CCI) scores, admission source, patient class, discharge disposition, length of stay (LOS), service line, surgeon and DRG were collected. Outcomes included ED visit utilization and readmissions. Descriptive statistics were performed and continuous variables were evaluated for normality using the Shapiro-Wilk test and through evaluation of histograms. Differences between pre-BPCI and BPCI groups were evaluated using Wilcoxon Rank Sum tests due to non-normal distributions, for continuous variables, and chi-square or exact tests for categorical variables, as appropriate. The odds of readmission or ED utilization were compared between BPCI and pre-BPCI groups using logistic regression. Analyses adjusted for potential confounders. RESULTS This study included 358 pre-BPCI and 63 BPCI patients (8 Decomp, 27 C_PSF, 30 L_PSF). We found no significant differences in age (median (IQR):70.3(9.2) vs 70.2(12.4) years), BMI (30.2(9.5) vs 31.4(9.1) kg/m2), LOS (4(3) vs 3(5) days), gender (51.7 vs 46.0% women), race (94.7 vs 96.8% white), MCC DRG (12.6 vs 17.5%) or discharge home (59.8% vs 61.9%, all p>0.05) in pre-BPCI vs BPCI patients, respectively. Patient class differences were noted (pre-BPCI:11.7 vs BPCI: 22.2% inpatient, p=0.024). Overall, the ED visit rates were similar in pre-BPCI (26.5%) vs BPCI patients (30.2%, p=0.551) though readmission rates were slightly lower following BPCI participation (15.9% vs 26.8%, p=0.065). There was also a trend for lower number of readmissions after BPCI (p=0.044) and analyses adjusted for service line and patient class revealed a greater odds of readmission in the pre-BPCI group vs BPCI (OR=2.53, 95%CI=1.14-5.58, p=0.022). Analyses stratified by bundles showed lower readmission rates in BPCI (8%) vs pre-BPCI group (27.5%, p=0.035) and a trend for lower readmission numbers (p=0.043) in the L_PSF bundle. However, no differences were noted in the Decomp or C_PSF bundles or for ED visits in any bundle (p>0.05). CONCLUSIONS Participation in spine bundled payments (BPCI-A) at a large academic medical center was associated with significantly lower readmission rates. Alignment of all stakeholder interests via a bundled payment framework may help mobilize additional health system resources to improve patients’ outcomes. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.