Learn About Knee Replacement

What is the definition of Knee Replacement?

Knee joint replacement is a surgery to replace a knee joint with a man-made artificial joint. The artificial joint is called a prosthesis.

What are the alternative names for Knee Replacement?

Total knee replacement; Knee arthroplasty; Knee replacement - total; Tricompartmental knee replacement; Subvastus knee replacement; Knee replacement - minimally invasive; Knee arthroplasty - minimally invasive; TKA - knee replacement; Osteoarthritis - replacement; OA - knee replacement

What happens during a Knee Replacement?

Damaged cartilage and bone are removed from the knee joint. Man-made pieces are then placed in the knee.

These pieces may be placed in the following places in the knee joint:

  • Lower end of the thigh bone -- This bone is called the femur. The replacement part is usually made of metal.
  • Upper end of the shin bone, which is the large bone in your lower leg -- This bone is called the tibia. The replacement part is usually made from metal and strong plastic.
  • Back side of your kneecap -- Your kneecap is called the patella. The replacement part is usually made from a strong plastic.

You will not feel any pain during the surgery. You will have one of these two types of anesthesia:

  • General anesthesia -- This means you will be asleep and unable to feel pain.
  • Regional (spinal or epidural) anesthesia -- Medicine is put into your spine to make you numb below your waist. You will also get medicine to make you sleepy. And you may get medicine that will make you forget about the procedure, even though you are not fully asleep.

After you receive anesthesia, your surgeon will make a cut over your knee to open it up. This cut is often 8 to 10 inches (20 to 25 centimeters) long. Then your surgeon will:

  • Move your kneecap out of the way
  • Cut the ends of your thigh bone and shin (lower leg) bone to fit the replacement part.
  • Cut the underside of your kneecap to prepare it for the new pieces that will be attached there.
  • Fasten the two parts of the prosthesis to your bones. One part will be attached to the end of your thigh bone and the other part will be attached to your shin bone. The pieces can be attached using bone cement or screws.
  • Attach the underside of your kneecap. A special bone cement is used to attach this part.
  • Repair (if needed) your muscles and tendons around the new joint and close the surgical cut.

The surgery takes about 2 hours.

Most artificial knees have both metal and plastic parts. Some surgeons now use different materials, including metal on metal, ceramic on ceramic, or ceramic on plastic.

Why would someone need a Knee Replacement?

The most common reason to have a knee joint replaced is to relieve severe arthritis pain. Your health care provider may recommend knee joint replacement if:

  • You are having pain from knee arthritis that keeps you from sleeping or doing normal activities.
  • You cannot walk and take care of yourself.
  • Your knee pain has not improved with other treatment.
  • You understand what surgery and recovery will be like.

Most of the time, knee joint replacement is done in people age 60 and older. Younger people who have a knee joint replaced may put extra stress on the artificial knee and cause it to wear out early and not last as long.

How to prepare for a Knee Replacement

Always tell your provider what medicines you are taking, even medicines, supplements, or herbs you bought without a prescription.

During the 2 weeks before your surgery:

  • Prepare your home for when you leave the hospital.
  • One to two weeks before surgery, you may be asked to stop taking medicines that make it harder for your blood to clot. These include aspirin, ibuprofen (Advil, Motrin), naproxen (Naprosyn, Aleve), blood thinners such as warfarin (Coumadin), or clopidogrel (Plavix), and other medicines (such as Eliquis or Xarelto).
  • You may also need to stop taking medicines that can make your body more likely to get an infection. These include methotrexate, etanercept (Enbrel), or other medicines that suppress your immune system. Make sure you ask your providers when it is safe to resume taking these medicines.
  • Ask your surgeon which medicines you should still take on the day of your surgery.
  • If you have diabetes, heart disease, or other medical conditions, your surgeon may ask you to see the provider who treats you for these conditions to see if it is safe for you to have the surgery.
  • Tell your provider and surgeon if you have been drinking a lot of alcohol, more than 1 or 2 drinks per day.
  • If you smoke, you need to stop. Ask your providers for help. Smoking will slow down wound and bone healing. Your recovery may not be as good if you keep smoking.
  • Always let your surgeon know about any cold, flu, fever, herpes breakout, or other illness you have before your surgery.
  • You may want to visit a physical therapist to learn some exercises to do before surgery.
  • Practice using a cane, walker, crutches, or a wheelchair correctly.

On the day of your surgery:

  • You will most often be asked not to drink or eat anything for 6 to 12 hours before the procedure.
  • Take the medicines you have been told to take with a small sip of water.
  • You will be told when to arrive at the hospital.
What to expect after a Knee Replacement

You may go home the same day or you may stay in the hospital for 1 to 2 days. During that time, you will recover from your anesthesia and from the surgery itself. You will be asked to start moving and walking as soon as the day of surgery.

Full recovery will take 4 months to a year.

Some people need a short stay in a rehabilitation center after they leave the hospital and before they go home. At a rehabilitation center, you will learn how to safely do your daily activities on your own.

What is the outlook (prognosis) for Knee Replacement?

The results of a total knee replacement are often excellent. The operation relieves pain for most people. Most people do not need help walking after they fully recover.

Over 90 percent of artificial knee joints last over 15 years. Some last as long as 25 years before they loosen and need to be replaced again. Total knee replacements can be replaced again if they get loose or wear out. However, in most cases the results are not as good as the first time. It is important not to have the surgery too early so you will need another surgery at a young age or have it too late when you will not benefit the most. After surgery, you should have periodic checkups with your surgeon to make sure the parts of your artificial joint are in good position and condition.

Who are the top Knee Replacement Local Doctors?

University Professional Services

3181 Sw Sam Jackson Park Rd, 
Portland, OR 
 12.1 mi
Accepting New Patients
Offers Telehealth

Ryland Kagan is an Orthopedics provider in Portland, Oregon. Dr. Kagan and is rated as a Distinguished provider by MediFind in Knee Replacement. His top areas of expertise are Osteoarthritis, Osteonecrosis, Menopause, Knee Replacement, and Hip Replacement. Dr. Kagan is currently accepting new patients.

Orthopedic And Fracture Clinic PC

11782 Sw Barnes Rd, Suite 300, 
Portland, OR 
 17.6 mi
Accepting New Patients

Elizabeth Lieberman is an Orthopedics provider in Portland, Oregon. Dr. Lieberman and is rated as an Experienced provider by MediFind in Knee Replacement. Her top areas of expertise are May Thurner Syndrome, Osteoarthritis, Osteolysis Syndrome Recessive, Hip Replacement, and Knee Replacement. Dr. Lieberman is currently accepting new patients.

 
 
 
 
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Sports Medicine
Sports Medicine
10000 Se Main St, Suite 327, 
Portland, OR 
 6.0 mi
Accepting New Patients

Patrick Hanley is a Sports Medicine provider in Portland, Oregon. Dr. Hanley and is rated as an Experienced provider by MediFind in Knee Replacement. His top areas of expertise are Baker Cyst, Tendinitis, Bursitis, and Knee Replacement. Dr. Hanley is currently accepting new patients.

What are the latest Knee Replacement Clinical Trials?
Analgesic Effect of Fentanyl Vs Dexmedetomidine As Adjuvant to Bupivacaine in Combined IPACK and Adductor Canal Block After Knee Surgeries

Summary: This study will be undertaken to compare the analgesic effects of of fentanyl versus dexmedetomidine as adjuvant to bupivacaine in combined IPACK and ACB for pain management after total knee arthroplasty.

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Methylprednisolone Taper After Total Knee Replacement: A Prospective Randomized Trial

Summary: Total knee replacement surgery is a commonly performed and widely successful surgery to improve mobility and decrease pain in patients suffering from severe knee arthritis. However, in the immediate period after knee replacement, patients often experience significant pain and nausea, which can limit early recovery after surgery. Glucocorticoids are anti-inflammatory drugs that can reduce pain and ...

Who are the sources who wrote this article ?

Published Date: August 27, 2024
Published By: C. Benjamin Ma, MD, Professor, Chief, Sports Medicine and Shoulder Service, UCSF Department of Orthopaedic Surgery, San Francisco, CA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

What are the references for this article ?

American Academy of Orthopedic Surgeons (AAOS) website. Treatment: total knee replacement. orthoinfo.aaos.org/en/treatment/total-knee-replacement. Updated February 2024. Accessed September 26, 2024.

Ellen MI, Forbush DR, Groomes TE. Total knee arthroplasty. In: Frontera WR, Silver JK, Rizzo TD Jr, eds. Essentials of Physical Medicine and Rehabilitation. 4th ed. Philadelphia, PA: Elsevier; 2019:chap 80.

Mihalko WM. Arthroplasty of the knee. In: Azar FM, Beaty JH, eds. Campbell's Operative Orthopaedics.14th ed. Philadelphia, PA: Elsevier; 2021:chap 7.