Disability Benefits for Knee Replacement

How SSA Evaluates a Knee Replacement

Total or partial knee replacement is evaluated under Blue Book listing 1.17, covering reconstructive surgery or surgical arthrodesis of a major weight-bearing joint. Because most knee replacements restore function within months, the listing targets the minority of cases with poor outcomes. Your medical records must establish all three elements:

• Qualifying surgery. A documented knee arthroplasty (total, partial, or revision) or surgical fusion of the knee.
• A 12-month limitation. An impairment-related limitation of musculoskeletal functioning that has lasted or is expected to last at least 12 continuous months. Common qualifying scenarios include prosthetic infection requiring removal and staged revision, arthrofibrosis (severe post-surgical stiffness), chronic instability or loosening, persistent pain despite a well-positioned implant, and complex regional pain syndrome after surgery.
• A documented need for a two-handed mobility device. Medical documentation of your need for a walker, bilateral canes, bilateral crutches, or a wheeled and seated mobility device involving both hands. One cane is not sufficient under this listing.

SSA can find the duration requirement met prospectively if your surgeon documents that device dependence is expected to persist a year or more — you do not need to wait 12 months to file. If both knees are replaced, or one knee is replaced while the other has severe arthritis, SSA must consider the combined effect, which strengthens both the listing argument and the RFC analysis. Claimants who walk unaided but cannot kneel, squat, climb, or stand for sustained periods will usually be evaluated under the RFC rules rather than the listing.

Medical Evidence SSA Needs for a Knee Replacement

SSA needs the surgical record — operative report, discharge summary, and any revision or manipulation-under-anesthesia procedures — plus post-operative imaging. X-rays showing loosening, malalignment, or periprosthetic fracture, and aspiration or lab results documenting infection, are powerful objective evidence of a failed or complicated replacement.

Orthopedic follow-up notes should record measured range of motion in degrees (arthrofibrosis is typically shown by flexion well below 90 degrees or a significant extension lag), stability testing, effusion, quadriceps strength, and gait. Physical therapy records matter: attendance, measured progress, plateaus, and the therapist's discharge status show whether your limitation is durable.

Document your continued device use through prescriptions and treatment notes explaining why a walker or bilateral support remains medically necessary. If you have pain out of proportion to imaging, ask your doctor to document the workup — infection ruled out, possible CRPS evaluated — so the record explains the pain rather than leaving it unsupported. Finally, a surgeon's written prognosis addressing the expected duration of your limitations and permanent restrictions (no kneeling, limited stairs, standing tolerance) directly addresses what the listing and RFC analyses require.

Qualifying Through Your Residual Functional Capacity

Most knee replacement claims are decided at the RFC stage. Even a successful replacement typically leaves permanent restrictions: no kneeling or crawling, limited squatting and stair climbing, and reduced tolerance for prolonged standing and walking. Surgeons commonly advise against high-impact activity for the life of the implant. For someone whose work history is construction, warehousing, nursing, food service, or other on-your-feet jobs, these restrictions alone rule out past work.

The RFC question then becomes what remains. A limitation to sedentary work — standing and walking no more than about two hours in an eight-hour day — combined with age 50 or older, a physical work background, and no transferable skills generally directs a finding of disabled under the medical-vocational grid rules; at 55, a light RFC can do the same. Younger claimants should document limitations that erode sedentary work: the need to elevate the leg to control swelling, a sit-stand option, cane use, chronic pain requiring medication that impairs concentration, or expected absences for revision surgery and follow-up. Swelling with prolonged sitting is common after knee replacement and worth documenting specifically, because it undermines the assumption that desk work is always possible.

Tips for a Stronger Knee Replacement Claim

Build a record that shows outcome, not just surgery.

• Have range of motion measured and charted at every orthopedic visit; numbers like "flexion 75 degrees" carry far more weight than "stiff knee."
• Document swelling patterns — how long you can sit or stand before the knee swells and what you must do about it.
• Complete physical therapy and keep the discharge summary; an unfinished course invites SSA to assume you would have recovered.
• If you need a revision or the other knee is failing, get that in writing — it supports the 12-month duration requirement.
• Get assistive devices prescribed rather than self-purchased, and use them consistently, including at consultative exams.
• Ask your surgeon for a statement of permanent restrictions; it is often the decisive document at the RFC stage.