Variation in the Delivery of Inpatient Orthopaedic Care to Medicaid Beneficiaries within a Single Metropolitan Region

Background There is variability in access to and utilization of orthopaedic care, particularly for those with Medicaid insurance. One potential contributor is perceived unwillingness of surgeons and hospitals to accept underinsured patients. We used administrative data to examine the payer mix for select inpatient orthopaedic surgical procedures at all hospitals within a single region, hypothesizing that the delivery of orthopaedic surgery to Medicaid beneficiaries varies highly at the hospital level. Methods Using administrative data, we analyzed inpatient hospitalizations for elective cases (total knee or hip arthroplasty; spinal decompression or fusion) and trauma cases (hip hemiarthroplasty; femoral or tibial and fibular fracture repair) among 22 hospitals in a single region from 2011 to 2016 for patients who were 18 to 64 years of age. The primary outcome was the percentage of each hospital's caseload with Medicaid listed as the primary payer. The secondary outcome measured each hospital's Medicaid percentage against the percentage of Medicaid-insured individuals within 10 miles of the hospital (Medicaid share ratio), using a ratio of 1 as a benchmark. To quantify variation, we calculated a weighted coefficient of variation of the Medicaid share ratio for all cases combined, elective cases only, and trauma cases only. Results For all cases (n = 19,204), the mean percentage of Medicaid-funded surgical procedures was 7.6% (range, 0.2% to 57.3%). The mean Medicaid share ratio was 1.0 (range, 0.05 to 4.20). Across 22 hospitals, the weighted coefficient of variation for Medicaid share was 69, indicating very high variation. For elective cases alone, the mean percentage of Medicaid-funded surgical procedures was 5.5% (range, 0.2% to 64.6%). The mean Medicaid share ratio was 0.71 (range, 0.05 to 4.73), and the weighted coefficient of variation was 93. For trauma cases alone, Medicaid-funded surgical procedures were 14.7% (range, 0.0% to 35.7%). The mean Medicaid share ratio was 2.0 (range, 0 to 3.93), and the weighted coefficient of variation was 34. Conclusions Delivery of care was highly variable when benchmarking against the insurance composition of each hospital's surrounding community. Although generalizability to other regions is limited, our findings support previously asserted notions that delivery of orthopaedic care may differ on the basis of socioeconomic markers (such as insurance status). If not addressed, these inequities may exacerbate existing racially and socioeconomically based disparities in care.