Usually yes — but the approval keys off your X-ray, not how much it hurts. Coverage needs advanced arthritis on imaging, function-limiting pain, and a documented conservative-care trial first. Check your situation against your plan's real criteria below.
Joint-replacement prior authorization runs through musculoskeletal benefit managers — eviCore (Cigna, Aetna) and Carelon (Anthem/Elevance) — and they converge on the same standard. The single most important document is recent weight-bearing imaging showing how advanced the arthritis is:
Severe pain with a clean or mild X-ray is the most common reason a request stalls — because on paper there's nothing yet for the surgeon to replace.
On top of the imaging, payers want all of:
Surgeons are also expected to optimize modifiable risks first — weight, blood sugar, smoking — and active infection, dialysis, or a severe uncorrectable deformity will block approval until addressed.
Answer a few plain questions about your imaging and treatment so far, and see exactly what to document before the request is filed — about two minutes, free.
Check my coverageUsually not yet. Most insurers require severe arthritis — Kellgren-Lawrence Grade 3–4, often described as "bone-on-bone" — before a total knee replacement is considered medically necessary. Moderate (Grade 2) changes typically don't qualify, no matter how much pain you're in. Recent weight-bearing films that document the true grade are the key, and sometimes the grade is higher than an older film suggested.
Generally yes — a documented trial of conservative care (physical therapy, anti-inflammatory or pain medication, injections, activity modification) for about 3 months is required before joint replacement is approved. The exception is when your surgeon documents a specific reason non-surgical care isn't appropriate for you.
Medicare has no national prior-authorization requirement for inpatient joint replacement, and it's no longer on the "inpatient-only" list. Coverage still depends on medical necessity — advanced arthritis and a failed conservative-care trial — and some regional contractors (MACs) publish local coverage determinations with their own specifics.
A high BMI usually isn't an absolute denial, but surgeons are expected to optimize modifiable risks — weight, blood sugar (A1c), and smoking — before surgery, and some plans flag a very high BMI for optimization first. It's worth addressing early so it doesn't delay approval.
Related: Why prior authorizations get denied · Advanced imaging · all coverage tools