Knee replacement surgery can relieve pain and restore mobility in this important joint. The most common reason for a knee replacement is osteoarthritis. This causes gradual wearing of the cartilage in your knee. Others need surgery because they’re born with knee defects or they’ve sustained an injury.

If you’re considering a knee replacement surgery, the first step is to undergo a thorough medical evaluation. This is a multi-stage process. It’s important to ask your doctor questions throughout the evaluation to determine if knee replacement surgery is the right treatment for you. Additionally, you’ll want to ask your doctor about recovery methods and options.

Read more: What do you want to know about total knee replacement? »

The evaluation process has many parts, including:

  • detailed questionnaire
  • X-rays
  • physical evaluation
  • consultation about the results

According to the American Academy of Orthopaedic Surgeons, 90 percent of people who have knee replacement surgery have a lot less pain afterward. Although effective at relieving pain, the surgery is complicated and recovery can take up to six months or a year. Because of this, a thorough evaluation is important.

Here are the steps of the evaluation process:


A detailed questionnaire will cover your medical history, pain level, limitations, and the progression of your knee pain and problems. Questionnaires may vary by doctor and clinic. The evaluation typically centers on whether you’re able to:

  • get in and out of a car
  • bathe
  • walk without a limp
  • walk up and down stairs
  • sleep at night without pain
  • move without your knee feeling as if it’s going to “give way” at any given moment

The questionnaire will also ask about your overall health and any existing conditions you have. These might include:

  • arthritis
  • osteoporosis
  • obesity
  • smoking
  • anemia
  • hypertension
  • diabetes

Your doctor will also want to know how any of these conditions have changed recently. Some of these existing health conditions, such as diabetes, anemia and obesity, can impact the treatment choices your doctor suggests. It’s important to mention any health problems during your evaluation.

Your doctor will use this information to diagnose your knee problems and determine the best treatment approach. If knee replacement is a viable option, they will perform a physical evaluation.

Physical Evaluation

During the physical evaluation, your doctor will measure your knee’s range of motion using a protractor-like instrument. They will extend your leg in front of you to determine the maximum extension angle, and flex it behind you to determine the maximum flexion angle. Together, these distances make up your knee’s total range of motion and flexibility.

Learn more about how your knee works and moves using Healthline’s Body Maps »

An Orthopedic Evaluation

Your doctor will also check to see if you’ve become bowlegged or knocked-kneed, test your muscle strength, and observe your overall ability to move around, including:

  • sitting
  • standing
  • taking steps
  • walking
  • bending
  • performing other basic activities


X-rays provide your doctor with details about the health of the bone in your knee. Your doctor will request a set of X-rays to view your knee joint and to determine if a knee replacement will likely improve your knee pain and function, and whether you are a candidate for surgery. They will compare your X-rays with the results of your evaluation and past X-rays. This will help them understand how your knees have changed or deteriorated over time.

Some doctors will also request an MRI to look at the soft tissues surrounding your knee. This will help them understand the current state of your knee and determine if there are other complications, such as infections or tendon problems. On occasion, your doctor will extract a fluid sample from your knee to verify that you do not have an infection.


Finally, your doctor will consult with you about your options. If your evaluation indicates that your joints are severely damaged and other treatments aren’t likely to provide relief, your doctor may recommend a knee replacement surgery.

With knee replacement surgery, the damaged portions of your joint and bones will be replaced with an artificial knee designed to mimic your original knee. This will provide you with long-term pain relief.

The evaluation is a long and thorough process. Be sure to ask your doctor any questions or concerns along the way. Here are some example questions to initiate a discussion about your health and options:

Alternatives to Surgery

  • What are the alternatives to surgery, and what are the pros and cons associated with those alternatives?

Knee Replacement Surgery

  • Will you perform traditional surgery or use a newer method?
  • How large will the incision be and where will it be located?
  • What are the potential risks and complications?

Surgery Recovery

  • How much less pain will I feel after a knee replacement? How much mobility will I gain after a knee replacement?
  • What benefits am I likely to experience?
  • How will my knee function in the future if the procedure isn’t done? What limitations and problems likely occur?
  • What activities will I be able to resume and what ones will no longer be possible?

Surgeon Expertise and Safety

  • Are you board-certified and have you served a fellowship? What was your specialty?
  • How many of these operations do you perform a year? What outcomes have you experienced?
  • Have you had to preform revision surgery on your knee replacement patients? If so, how often and what are the typical reasons?
  • What steps do you and your staff take to ensure the best possible outcome?
  • Hospital Stay

    • How long should I expect to be in the hospital?
    • Are you available after surgery to answer questions and address concerns?
    • At which hospital or clinic will you perform the surgery?
    • Is knee replacement a common surgery performed at this hospital?

    Risks and Complications

  • What specific risks are associated with this procedure?
  • What type of anesthesia is used during this procedure? What are the risks?
  • Do I have any health conditions that would make my surgery more complicated or risky?
  • What are the most common post-surgery complications?
  • The Implant

    • Why are you choosing the prosthetic device you’re recommending?
    • What are the pros and cons of other devices?
    • How can I learn more about the implant you are selecting for my knee replacement?
    • How long is this device going to last?
    • Have there been problems associated with this particular device or company?

    Recovery and Rehabilitation

    • What is the typical recovery process like? What should I expect?
    • What does the typical rehabilitation involve and what is a reasonable time for recovery?


    • How much will this procedure cost?

    Alternatives to Surgery

    • What are the alternatives to surgery, and what are the pros and cons associated with those alternatives?

    Knee replacement is effective at relieving pain, restoring flexibility, and helping you live an active life. The surgery is complicated and the recovery is a long process. That’s why an in-depth evaluation process is essential. It’s important to ask your doctor lots of questions during the evaluation to determine if this surgery is the right treatment for you.