Knee Replacement Surgery: What Patients Need to Know Before Deciding

Who Is a Candidate for Knee Replacement?

Knee replacement is one of the most performed elective orthopedic surgeries in the United States, with roughly 700,000 procedures done annually. The operation replaces the worn surfaces of the knee joint — the ends of the femur, tibia, and in most cases the underside of the kneecap — with metal and polyethylene components that restore smooth, pain-free movement.

The procedure is most commonly recommended for severe knee osteoarthritis, but it is also used to treat the joint destruction caused by rheumatoid arthritis and post-traumatic arthritis following significant knee injuries. Candidacy is not determined by age alone. The decision is based on how much pain and functional limitation you have, whether conservative treatments have been adequately tried, and whether the X-ray findings are consistent with what you're experiencing.

Indicators that surgery may be appropriate include knee pain that is present at rest or that wakes you at night, significant stiffness and difficulty bending or straightening the knee, and an inability to walk, climb stairs, or perform daily activities comfortably despite using medication, injections, or physical therapy.

Types of Knee Replacement

Not every knee replacement is the same. The two most common options are:

Total knee replacement (TKR) replaces all three compartments of the knee — the medial (inner), lateral (outer), and patellofemoral (front) compartments. This is appropriate when arthritis affects most of the joint surface.

Partial (unicompartmental) knee replacement resurfaces only the affected compartment, typically the medial side. It requires a smaller incision, preserves more bone and the native ligaments, and often allows for a faster recovery. Not every patient is a candidate — the other compartments must be healthy and the ligaments intact.

Your surgeon will review your X-rays and clinical exam to determine which approach best fits your anatomy and degree of disease.

What to Expect from Surgery and Recovery

Knee replacement is performed under spinal or general anesthesia and typically takes one to two hours. Most patients are walking with assistance on the day of surgery and go home within one to three days. The shift toward outpatient and same-day procedures has accelerated in recent years for appropriate patients.

Physical therapy begins immediately and continues for several weeks after surgery. Early motion is critical — the goal in the first days is to achieve adequate bend and full extension in the knee before scar tissue sets in. Most patients are walking without an assistive device within four to six weeks and reach their full functional improvement by three to six months.

Complications are uncommon but include blood clots, infection, stiffness, and implant loosening over time. Modern implants are durable; published data show that more than 90 percent of total knee replacements remain functional at 15 years.

Having a Realistic Conversation with Your Surgeon

The most important step before deciding on knee replacement is a thorough consultation. Come prepared to describe your pain pattern, what activities you can and cannot do, and what you've already tried. Bring prior imaging if you have it. Ask your surgeon to explain what findings on your X-ray support the recommendation, what the realistic expectations for pain relief and function are, and what the recovery timeline will look like given your specific situation.

Knee replacement reliably reduces pain and improves function for the right patients, but it is not a procedure to undertake before conservative measures have been given a fair trial. A transparent conversation about expectations — including what the implant cannot do, such as restore the feel of a natural knee or support high-impact sports — sets the foundation for a good outcome.

If you're experiencing persistent knee pain that is limiting your daily activities, the specialists at Maryland Orthopedic Specialists can help. Call (301) 515-0900 or [schedule an appointment online](https://www.mdorthospecialists.com/contact).