When you have a knee injury or arthritis, particularly osteoarthritis, the damage, inflammation, and pain can limit your ability to flex and extend your knees. Over time, the deterioration of your joint and surrounding tissue can make it difficult to perform basic daily activities, even sitting and lying down. Knee replacement surgery is a common solution for people whose knees have become too worn from this deterioration.

Knee replacement provides dramatic pain relief for more than 90 percent of those who’ve undergone this surgery. Most of these procedures are done to replace knees damaged by osteoarthritis. The procedure was introduced in 1968. Total knee replacement is considered one of the safest and most effective procedures in orthopedics.

During a total knee replacement, a surgeon removes some bone and cartilage from the areas of your thighbone and shin bone, where they meet at your knee joint. The surgeon then replaces the knee area of your thighbone with a metal implant and the knee area of your shinbone with a plastic implant. This gives both bones of your knee joint smooth surfaces again so they can flex and bend more freely and painlessly. In many cases, the surgeon also replaces the undersurface of your kneecap with a plastic coating.

There are many things to consider when you are deciding whether to have total knee replacement. This video highlights these considerations.

Partial knee replacement involves only replacing the part of your knee that’s damaged or arthritic. The advantage to this approach is that it requires a smaller incision. It also involves less bone and blood loss. As well, it causes less pain during recovery than a total knee replacement.

People who have a partial knee replacement tend to have a faster recovery time than those who have a total knee replacement. However, there are disadvantages, including the possibility that you’ll have to eventually have further surgery if arthritis develops in the parts of the knee that aren’t replaced.

Bilateral knee replacement surgery is the replacement of both of your knees at the same time. An advantage to bilateral knee replacement is that you only have to go through this procedure and recovery process once if both of your knees are affected.

However, a disadvantage is that the recovery time takes longer, and you’re more likely to need much more assistance during recovery. Learn more about what is involved in the process and recovery of bilateral knee replacement.

The cost of a total knee replacement can vary. It can depend on where you’re having the procedure and your health at the time of the replacement. If you have other conditions that are not related to your knees, they may affect the procedure and cost as well.

When you’re considering the cost of the procedure, you should also consider all of the related costs, such as your hospital stay and physical therapy in the hospital and during your recovery at home.

You should also know how much of the cost that your insurance will pay and how much you’ll be expected to pay out of your own pocket. This Healthline article outlines many of the cost considerations you should be aware of when deciding to have total knee replacement surgery.

After a total knee replacement, you should expect to spend three to five days at the hospital. Usually before you leave the operating room, your knee may be cradled in a passive motion machine, and medical staff will monitor the flexion (bending in) and extension (straightening out) limits of your knee.

You might begin weight-bearing therapy immediately after the operation. In addition, you will have some combination of physical and occupational therapy at the hospital. In most cases, you’ll likely be able to stand and walk, at least with the assistance of a cane or walker, before you leave the hospital.

Most of your recovery and rehabilitation will be at home after you leave the hospital. Some people need home health care or assistance.

Your doctor will most likely prescribe physical therapy at a local clinic for continued rehabilitation. The physical therapist at this clinic will suggest exercises you can do at home.

Everyone recovers a little differently following a total knee replacement. It generally takes 12 weeks to complete the rehab process and 6 months to a year to get back to full strength. Here's a detailed timeline of the rehabilitation and recovery process after a total knee replacement.

During recovery from total knee replacement, your physical therapist will most likely have an exercise protocol for you to follow. These exercises will help to strengthen your knee and speed up your healing. It’s important for you to closely follow this protocol so that your recovery stays on track and you return to your normal daily activities as quickly as possible.

You may be able to speed this process up further by strengthening the area around your knee before surgery. Learn some exercises that you can do before surgery that may help to make your recovery time shorter.

You’ll have pain for a while after your knee replacement. However, your doctor will give you medication to help manage this. It’s important to let your doctor know how well your medication is working for you. Find out what to expect and ways to manage any pain you may experience after having a knee replacement.

A typical knee replacement lasts between 15 years and 20 years. According to the American Academy of Orthopaedic Surgeons, currently more than 90 percent of modern total knee replacements are still functioning well 15 years after surgery. The American Association of Hip and Knee Surgeons states that there is between an 80 percent and 85 percent chance that your total knee replacement will last 20 years. Learn the answers to more common questions that people have about total knee replacement.

Today, knee replacements are safe. Very few people have complications. Thoroughly discuss the benefits and risks of total knee replacement with your surgeon about this procedure before you decide to have it. You may also want to consider the cost of surgery and follow-up care as well as how much time you’ll need to take off from work for recovery and rehabilitation.

Total knee replacement increasingly is an attractive and viable option for many people, especially those dealing with chronic knee pain or unable to participate in common activities. After surgery and recovery, many people are able to participate in activities they used to do, such as walking, bicycling, golf, tennis, and swimming. As the pain from surgery begins to go away and you’re able use your knee like you used to, your quality of life will most likely improve.