What Is Knee Replacement Surgery and What Should You Expect?

Updated

Knee replacement surgery replaces damaged surfaces of the knee joint with artificial components to reduce pain and restore function, and it is typically considered when joint damage from arthritis or injury no longer responds well to non-surgical treatment. The two main versions are total knee replacement, which resurfaces all three compartments of the knee, and partial knee replacement, which replaces only the worn compartment. What you should expect depends on which type you and your surgeon choose, how the procedure is performed, and how consistently you follow rehabilitation afterward.

Total vs. partial knee replacement

Total knee replacement Partial knee replacement
What is replaced All three compartments of the knee Only the damaged compartment
Typical candidate Widespread arthritis or damage across the joint Damage limited to one compartment
Incision and tissue disruption Generally larger Generally smaller
Recovery Often longer Often faster, but varies by patient

Both are intended to relieve pain and improve motion. The right choice is a clinical judgment based on where the damage is, your overall health, and your surgeon's assessment — not a preference you can settle on your own.

Why knee replacement is recommended

The most common driver is osteoarthritis, where cartilage wears down and bone surfaces rub together. Other reasons include inflammatory arthritis and joint damage from injury. Signs that surgery may be worth discussing:

  • Persistent pain that limits walking, stairs, or sleep
  • Stiffness that restricts daily activities
  • Pain that has not improved enough with medication, injections, or physical therapy
  • X-rays or other imaging showing significant joint damage

Pain level alone is not the deciding factor. Imaging findings, your function, and your response to other treatments all feed into the recommendation.

How the procedure is performed

Knee replacement is a surgical procedure, usually performed in a hospital or specialty surgical facility. The damaged surfaces are removed and replaced with metal and plastic components sized to your anatomy.

Technique varies. Traditional instrumentation relies on the surgeon's manual alignment and measurement. Robotic-assisted systems add a planning and guidance layer — for example, the Rosa Knee and Mako systems are used for partial and total knee procedures, alongside other robotic-assisted surgery at some facilities. Robotic assistance is a tool for precision and planning; it does not by itself guarantee a better outcome, and whether it is used depends on the surgeon and the facility.

What recovery involves

Recovery is a process measured in weeks to months, not days. A realistic outline:

  1. Hospital stay and early movement. You will typically begin moving the knee soon after surgery with assistance, and pain is managed with medication.
  2. Physical therapy. Structured therapy — often starting in the hospital and continuing outpatient — is central to regaining strength and range of motion. This is the part patients most often underestimate.
  3. Return to daily activities. Walking and light daily tasks usually come back first; driving, work, and recreational activity return on a timeline your surgeon sets based on your progress.
  4. Longer-term function. Improvement can continue for many months. Full benefit depends heavily on adherence to therapy.

Common sticking points: expecting to skip or shorten therapy, comparing your timeline to someone else's, and pushing activity faster than your surgeon advises.

How to prepare and what to ask

Preparation covers the practical as well as the medical:

  • Arrange help at home for the first days or weeks
  • Plan for transportation, since you will not be able to drive immediately
  • Set up your living space to reduce stairs and tripping hazards
  • Follow your surgeon's instructions on medications, fasting, and stopping certain drugs before surgery
  • Ask about financial planning and payment options in advance

Questions worth asking your surgeon:

  • Is total or partial replacement the better fit for my knee, and why?
  • Will you use traditional or robotic-assisted technique, and how does that change my plan?
  • What is your typical recovery timeline, and what milestones should I expect?
  • How many of these procedures do you perform, and what outcomes do you see?
  • What are the risks and possible complications for my situation?
  • What will physical therapy look like, and for how long?

Facilities that specialize in joint replacement, such as Kansas Surgery & Recovery Center, a physician-owned orthopedic specialty hospital that states it consistently ranks high for joint replacement surgery by HealthGrades, typically publish new-patient information, joint seminar schedules, financial planning, price transparency, and self-pay options. Checking those pages before your consultation gives you concrete questions to bring to the surgeon.