Date of Award

January 2016

Document Type


Degree Name

Medical Doctor (MD)



First Advisor

Richard R. Pelker


PURPOSE: Although insurance coverage for Medicaid patients have increased under the Affordable Care Act, actual access to care may be limited. The purpose of this study was to evaluate national access to knee replacement and revision.

METHODS: The research team called 250 joint arthroplasty surgeons who performed primary knee replacement in 8 representative states (California, Massachusetts, Ohio, New York, Florida, Pennsylvania, Texas, and North Carolina) and revision in 4 representative states (California, Ohio, Florida, and Texas). The caller requested an appointment for her fictitious mother to be evaluated for a primary knee arthroplasty or revision. Each office was called three times to assess the responses for Medicaid, Medicare, or BlueCross. From each call, we recorded whether an appointment was given and barriers to an appointment, such as need for a referral.

RESULTS: Overall, patients with Medicaid were significantly less likely to receive an appointment compared to patients with Medicare or BlueCross (p < 0.001). However, patients with Medicaid had increased success at making an appointment in states with expanded Medicaid eligibility for knee replacement (37.7% vs 22.8%, p = 0.011), but not for revision (42.6% vs 26.9%, p = 0.09). The overall waiting period was longer for both knee replacement (p = 0.004) and knee revision (p < 0.0001) in states with expanded Medicaid eligibility compared to states without expanded eligibility. Higher Medicaid reimbursement also had a direct correlation with appointment success rate for Medicaid patients for knee revision (OR = 1.314, CI = 1.06 – 1.64, p = 0.014) but not for primary knee replacement (OR = 1.11, CI = 0.97 – 1.28, p = 0.13). For a total knee replacement, Medicaid reimbursed orthopaedic surgeons at 77% of Medicare rates, while for a knee revision, Medicaid reimbursed at 65% of Medicare rates.

CONCLUSION: Despite the passage of the Affordable Care Act, patients with Medicaid continue to have reduced access to care for knee arthritis and more complex barriers to receiving an appointment. Although Medicaid was accepted at a higher rate in states with expanded Medicaid eligibility, a more robust strategy for increasing access to care for patients with Medicaid is required.


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