After Medicaid expansion, 'unmet need' for joint replacement surgery

States that have expanded Medicaid eligibility under the Affordable Care Act have seen an "early surge in demand" for hip and knee replacement surgery, reports a study in the September 2, 2020 issue of The Journal of Bone & Joint Surgery.

"Patients with Medicaid expansion plans have a shorter time from enrollment to the surgical procedure, suggesting that there may be an unmet need for total hip arthroplasty [THA] and total knee arthroplasty [TKA] among newly enrolled Medicaid expansion beneficiaries," according to the new research by Christopher J. Dy MD, MPH, and colleagues of Washington University School of Medicine, St. Louis, Mo. "This need should be considered by surgeons, hospitals, and policymakers in ensuring access to care."

Shorter Times to THA and TKA in Medicaid-Expansion Patients

With use of data from a Medicaid managed care program, the researchers analyzed the timing of primary THA and TKA procedures in adults under age 65 between 2008 to 2015. The study included patients in four states that expanded Medicaid eligibility in 2014 (Illinois, Ohio, Oregon, and Washington) and four states without Medicaid expansion (Louisiana, Mississippi, Texas, and Wisconsin).

Times to joint replacement surgery were compared for Medicaid-expansion patients, a relatively healthy group of adults without dependent children; Medicaid patients with Supplemental Security Income (SSI), a group of relatively unhealthy adults with disabilities; and patients receiving Temporary Assistance for Needy Families (TANF), who are parents of children with Medicaid insurance. The analysis included a total of 4,117 patients across groups.

The median time to THA or TKA surgery for Medicaid-expansion patients (7.5 months) was significantly shorter than for SSI patients (16.1 months) and TANF patients (12.2 months).

A further analysis was adjusted for other factors, including patient age and sex, social deprivation, surgeon supply and reimbursement, and state-level Medicaid enrollment. The results of that analysis suggested that the time to THA or TKA was 70 percent shorter for Medicaid-expansion patients than for SSI patients. For TANF patients, the time to THA or TKA was 24 percent shorter than for SSI patients.

Expansion of state Medicaid programs has led to dramatic increases in insurance coverage among Americans. In August, Medicaid expansion was approved by voters in Missouri, making it the 38th state to expand Medicaid coverage.

Medicaid-expansion states have seen increases in certain 'elective' but medically indicated surgical procedures, including THA and TKA, which raises questions of whether pent-up demand will strain the capacity of the health-care system or exceed the supply of orthopedic surgeons willing to accept Medicaid insurance.

The new study finds a significantly shorter time from enrollment to THA and TKA for Medicaid-expansion patients compared with those with other routes of access to Medicaid coverage. "Our findings may represent an unmet need for THA and TKA among newly enrolled beneficiaries with Medicaid expansion plans," Dr. Dy and coauthors write. They suggest that Medicaid expansion is likely to lead to "an early surge in demand rather than a gradual increase."

"This need should be considered by surgeons, hospitals, and policymakers in ensuring access to care," Dr. Dy and coauthors conclude. They believe that healthcare policy and resource planning should also consider the existing disparities in access to orthopedic care already faced by Medicaid patients, as surges in demand may exacerbate these differences.