Regional (spinal or epidural) anesthesia. You will be numb below your waist. You will also get medicines to make you relax or feel sleepy.
The surgeon will make a cut over your knee. This cut is about 3 to 5 inches long.
Next, the surgeon looks at the entire knee joint. If there is damage to more than one part of your knee, you may need a total knee replacement. Most of the time this is not needed, because tests done before the procedure would have shown this damage.
The damaged bone and tissue are removed.
A part made from plastic and metal is placed into the knee.
Once the part is in the proper place, it is attached with bone cement.
The wound is closed with stitches.
Why the Procedure Is Performed
The most common reason to have a knee joint replaced is to ease severe arthritis pain.
Your health care provider may suggest knee joint replacement if:
You can't sleep through the night because of knee pain.
Your knee pain prevents you from doing daily activities.
Your knee pain has not gotten better with other treatments.
Partial knee arthroplasty may be a good choice if you have arthritis in only one side or part of the knee and:
You are older, thin, and not very active.
You do not have very bad arthritis on the other side of the knee or under the kneecap.
You have only minor deformity in the knee.
You have good range of motion in your knee.
The ligaments in your knee are stable.
However, most people with knee arthritis have a surgery called a total knee arthroplasty (TKA).
Knee replacement is most often done in people age 60 and older. Not all people can have a partial knee replacement. You may not be a good candidate if your condition is too severe. Also, your medical and physical condition may not allow you to have the procedure.
Ask your provider which medicines you can still take on the day of your surgery.
You may be asked to stop taking medicine that makes it harder for your blood to clot. These include aspirin, ibuprofen (Advil, Motrin), naproxen (Naprosyn, Aleve), blood thinners such as warfarin (Coumadin), and other drugs.
You may need to stop taking any medicines that weaken your immune system, including Enbrel and methotrexate.
If you have diabetes, heart disease, or other medical conditions, your surgeon will ask you to see the provider who treats you for these conditions.
Tell your provider if you have been drinking a lot of alcohol (more than one or two drinks a day).
If you smoke, you need to stop. Ask your health care providers for help. Smoking slows healing and recovery.
Let your provider know if you get a cold, flu, fever, herpes breakout, or other illness before your surgery.
You may want to visit a physical therapist before surgery to learn exercises that can help you recover.
You can put your full weight on your knee right away.
After you return home, you should try to do as much as you can. This includes going to the bathroom or taking walks in the hallways with help. You will also need physical therapy to improve range of motion and strengthen the muscles around the knee.
Most people recover quickly and have much less pain than they did before surgery. People who have a partial knee replacement recover faster than those who have a total knee replacement.
Many people are able to walk without a cane or walker within 3 to 4 weeks after surgery. You will need physical therapy for 4 to 6 months.
Partial knee replacement can have good results for some people. Partial inside or outside replacement has good outcomes for up to 10 years after surgery. Partial patella or patellofemoral replacement does not have as good long term results as the partial inside or outside replacements. You should discuss with your health care provider whether you are a candidate for partial knee replacement and what the success rate is for your condition.
American Academy of Orthopedic Surgeons (AAOS). Treatment of osteoarthritis of the knee: Evidence-based guideline 2nd edition (summary). Rosemont, IL. Published May 18, 2013.
Richmond J, Hunter D, Irrgang J, et al. American Academy of Orthopaedic Surgeons. Treatment of osteoarthritis of the knee (nonarthroplasty). J Am Acad Orthop Surg. 2009;17:591-600. PMID: 19726743 www.ncbi.nlm.nih.gov/pubmed/19726743.
C. Benjamin Ma, MD, Professor, Chief, Sports Medicine and Shoulder Service, UCSF Department of Orthopaedic Surgery, San Francisco, CA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.