What Is Total Knee Replacement?
Total knee replacement (TKR), also called total knee arthroplasty, is a surgical procedure in which a damaged or worn knee joint is resurfaced using artificial implants made of metal alloys, high-grade plastics, and polymers. It is one of the most commonly performed orthopedic surgeries, typically recommended for patients with severe knee arthritis or joint damage that has not responded to conservative treatments.
When Is Knee Replacement Recommended?
Surgeons typically recommend TKR when:
- Knee pain significantly limits everyday activities like walking, climbing stairs, or rising from a chair
- Moderate to severe pain occurs even at rest or during sleep
- Non-surgical treatments — including physical therapy, anti-inflammatory medications, and injections — have provided insufficient relief
- Knee stiffness limits range of motion even after extended rest
- Imaging confirms substantial joint damage or bone-on-bone contact
Before the Surgery: Preparation
Preparation is an important part of a successful outcome. Your surgical team will guide you through:
Medical Evaluation
You'll undergo blood tests, an EKG, and possibly imaging to assess your overall health and fitness for surgery. Any chronic conditions like diabetes or heart disease must be well-controlled beforehand.
Medication Adjustments
Some medications — including blood thinners, anti-inflammatories, and certain supplements — may need to be paused in the days before surgery to reduce bleeding risk.
Prehabilitation
Strengthening the muscles around your knee before surgery ("prehab") has been shown to improve post-operative recovery. Your care team may recommend a short course of physical therapy in advance.
Home Setup
Arrange your home for a safe return: remove trip hazards, install grab bars in the bathroom, and prepare a recovery area on the ground floor if possible.
During the Surgery
The procedure itself typically takes one to two hours and is performed under general or spinal anesthesia. The surgeon removes damaged cartilage and bone from the surface of the knee joint, then positions the prosthetic components to restore proper alignment and function. A spacer made of medical-grade plastic is inserted between the metal components to create a smooth gliding surface.
After the Surgery: Recovery Timeline
Days 1–3: Hospital Stay
Most patients begin physical therapy as early as the day after surgery to promote circulation and prevent stiffness. You'll be encouraged to stand and take assisted steps with a walker before leaving the hospital.
Weeks 1–6: Early Recovery
- Pain and swelling are managed with prescribed medications and ice therapy
- A physical therapist guides you through exercises to restore range of motion
- Most patients transition from a walker to a cane within 2–4 weeks
- Driving is typically possible after 4–6 weeks (right leg surgery)
Weeks 6–12: Strengthening Phase
Therapy intensifies to build strength in the quadriceps, hamstrings, and calf muscles. Most patients resume light daily activities comfortably during this window.
3–6 Months: Return to Activities
The majority of patients return to low-impact activities such as walking, swimming, and cycling. Full recovery — feeling comfortable with the prosthesis and experiencing minimal discomfort — can take up to a year.
Potential Risks and Complications
As with any major surgery, risks exist. These include:
- Blood clots (deep vein thrombosis) — preventable with blood-thinning medications and movement
- Infection — minimized with sterile technique and prophylactic antibiotics
- Implant loosening or wear over time
- Stiffness or limited range of motion if post-op therapy is not followed
- Nerve or blood vessel injury (rare)
Key Questions to Ask Your Surgeon
- Am I a good candidate for total knee replacement versus partial replacement?
- What type of implant will be used, and why?
- How many knee replacements do you perform each year?
- What does the rehabilitation program look like?
- What restrictions will I have after surgery and for how long?
Knee replacement surgery carries a strong track record for relieving pain and restoring mobility. Understanding the full process empowers you to prepare thoughtfully and engage actively in your recovery.