Trouble with your knee? What you need to know about knee replacement surgery

From why you might need a knee replacement to what it costs and how long it takes to recover from surgery, here are the answers you’re looking for.
Close up of hands of older woman resting on knees
“Overall, it’s a widely successful surgery,” said Dr. Bryan D. Springer. “If you look across all surgeries it’s one of the most frequently utilized — that’s based on success.”Shestock / Getty Images

If you have ongoing knee pain, you know it can affect your life. You might struggle to walk a few blocks or climb stairs. The pain can wake you up at night. You avoid activities you used to enjoy, knowing that they’ll cause your pain to flare.

If it’s arthritis that’s behind your knee pain, you might be a candidate for knee replacement surgery, also known as knee arthroplasty.

What is knee replacement surgery?

It’s a procedure in which a surgeon removes the cartilage in your knee that’s been damaged by arthritis, as well as the nearby bone. The joint is replaced with an artificial joint that’s made of smooth metal and plastic parts.

According to the American Association of Orthopedic Surgeons (AAOS), the procedure has been performed for more than 50 years, and more than 790,000 people in the United States have a knee replaced every year.

The success rate for knee replacement surgery is high. “Overall, it’s a widely successful surgery,” Dr. Bryan D. Springer, fellowship director of the OrthoCarolina Hip and Knee Center in Charlotte, North Carolina, and a spokesperson for the AAOS, told TODAY. “If you look across all surgeries it’s one of the most frequently utilized — that’s based on success.”

What to expect from knee replacement surgery

To see if knee replacement surgery might be right for you, your doctor will want to confirm that you have arthritis. “You have to see that something’s wrong on the x-ray,” Dr. Claudette M. Lajam, an orthopedic surgeon at NYU Langone Health in New York City and a spokesperson for the AAOS, told TODAY. “You can be fooled by other disease processes.” For example, a damaged disc in your back could cause pain in your knee.

To see if knee replacement surgery might be right for you, your doctor will want to confirm that you have arthritis.real444 / Getty Images

If you have arthritis, you won’t go straight to surgery. Your doctor will want you to try other, less-invasive strategies to reduce your pain.

Those might include:

  • Modifying your activities
  • Taking anti-inflammatory medications
  • Stretching
  • Getting steroid injections
  • Doing physical therapy
  • Wearing a knee brace
  • Using shoe inserts

These options can be good alternatives to knee replacement surgery for elderly patients or others who can’t undergo surgery.

If these strategies aren’t controlling your pain, it might be time to consider knee replacement surgery. “If the pain is interfering with your life and you can’t make it better with other means, you have to consider other ways to fix it,” Lajam said.

Dangers of delaying knee replacement surgery

While it’s important to exhaust your other options for alleviating your pain, you shouldn’t wait too long. There are some dangers of delaying knee replacement surgery.

What happens if you don’t have knee replacement surgery? Lajam worries that people who try to live with the pain for too long will see their independence and health suffer. They could become more sedentary, lose control of conditions like diabetes and gain weight — and those factors all increase risk for complications from surgery.

Focus on your surgeon, not on the device or technique

Newer technologies like computer navigation can help surgeons be more precise in how they position the implant components during knee replacement surgery. But there’s a lot of information to sift through.

Between advertising, the internet and conversations with other people who’ve had knee replacements, you may have questions about your prosthesis and your surgeon’s technique.

Different types of knee replacement surgeries

You may wonder whether robotic knee replacement surgery is better. You might come across information about different types of knee replacement surgeries and the latest developments in knee replacement surgery, minimally invasive knee replacement surgery, lateral knee replacement surgery, alternative knee replacement surgery techniques and robotic versus traditional knee replacement surgery.

Springer says it can be hard for people to sift through the conflicting information they find. “People come in and say they want a certain type of prosthesis, or a specific technique or technology,” he said.

Surgeons usually have reasons for choosing the devices and techniques they use. “I tell patients to focus on researching your surgeon. Once you’ve found a surgeon you mesh with, have an open and honest discussion of techniques and technologies to find what’s best for you,” Springer said.

Knee replacement is major surgery, so it’s natural for people to look for easier alternatives. They sometimes ask about non-invasive knee replacement surgery. But it’s impossible to perform surgery non-invasively. They also ask about cartilage replacement knee surgery. That can work, according to the Arthritis Foundation, but it’s typically recommended for people who have injured their cartilage.

What’s the cost of a knee replacement surgery?

The cost varies. The average cost of knee replacement surgery with insurance in the U.S. will depend on your coverage, copays and deductible. A Blue Cross Blue Shield study found claims of just over $11,000 to almost $70,000, depending on where the surgery was performed.

Your surgeon’s office can work with you to calculate how much of the cost Medicare or your insurance company will cover and how much will fall to you.

How to prepare for knee replacement surgery

You’ll want to weigh the pros and cons of knee replacement surgery — it’s a major operation.

Risks are rare, Dr. John Wang, a hip and knee surgeon at the Hospital for Special Surgery Florida, told TODAY. Infection tops the list of knee replacement problems after surgery and occurs in 1 to 2% of patients, he said. People who are sedentary, overweight or have health conditions that aren’t well controlled are at higher risk for knee replacement surgery complications.

People who are sedentary, overweight or have health conditions that aren’t well controlled are at higher risk for knee replacement surgery complications.sasirin pamai / Getty Images

There’s no upper age limit for the surgery. When doctors evaluate the risks of knee replacement surgery in the elderly, they are more concerned with other health conditions, overall strength and cognitive function rather than a specific age cutoff. Jane Fonda is 82 and she is awaiting a second knee replacement surgery.

Getting ready for surgery and recovery

Once you and your doctor have decided that it’s the right choice for you, you can start to prepare.

You want to be as healthy as possible going into surgery — that’s a key part of how to avoid complications. Losing weight, improving fitness and managing your medical conditions can help.

Wang said some people start “prehab” and do exercises to prepare for knee replacement surgery. These exercises strengthen the muscles around the knee, so recovery is easier.

Of course, exercise is tough when your knees ache. Lajam says exercising in a pool can help. Water exercises help strengthen the legs, improve aerobic capacity and aid in weight loss. “People get hooked on it. They can’t wait to get back into the pool after surgery,” she said.

What tests are done before knee replacement surgery?

Your doctor will likely recommend a physical and a pre-op visit to talk about the surgery and recovery. At your pre-op visit, be sure to cover the questions to ask before knee replacement surgery.

Ask about:

  • Side effects of knee replacement surgery
  • How long you have pain after knee replacement surgery
  • What to wear after knee replacement surgery
  • How much time off work you’ll need to take in recovery from knee replacement surgery
  • Whether you’ll have insomnia after knee replacement surgery
  • How to find comfortable sleeping positions after total knee replacement surgery
  • What’s the expected recovery time for knee replacement surgery
  • If you can take ibuprofen after knee replacement surgery
  • How to elevate your knee after knee replacement surgery
  • Whether to expect blood clots after knee replacement surgery
  • Whether to expect bruising after knee replacement surgery
  • Whether to expect itching after knee replacement surgery
  • Whether to expect fluid on the knee after knee replacement surgery
  • If it’s possible you’ll have nerve damage after knee replacement surgery
  • What’s considered excessive swelling after knee replacement surgery
  • What your knee replacement surgery scar will look like
  • Which shoes are best for walking after knee replacement surgery
  • How soon you can fly after knee replacement surgery
  • What not to do after knee replacement surgery

As your surgery date approaches, your doctor will review your medications and supplements and recommend those you should take or stop taking before your procedure.

Prepare your home

It’s a good idea to get your home ready so it’s easier for you to recover after surgery.

Consider:

  • Nailing down loose carpet so you can navigate with a walker, crutches, or cane
  • Adding a riser to your toilet seat
  • Setting up a bed on your main living floor if you need to climb stairs to get to or from your bedroom
  • Stocking up on meals that are easy to reheat
  • Lining up care for your pets

“You want to make sure you’re setting everything up so you’re not worrying about things. You want to be focusing on getting better,” Lajam said.

The night before knee replacement surgery, your doctor will probably advise you not to have anything to eat or drink after midnight. You might need to take medication or shower with special soap.

Do I need someone to stay with me after knee replacement surgery?

It’s a good idea to have someone there for the first few days. “You just had major surgery. You want someone there to help you if something happens to you,” Lajam said. If you don’t have anyone who can stay with you, make sure you have someone who can call or stop by to check on you regularly.

What you need to know about surgery and recovery

How long does knee replacement surgery take? Generally, the procedure takes about an hour, Wang said: “It’s not a long surgery anymore.” Surgical techniques have improved over the years, so there’s less disruption to muscles and tendons. And advances in anesthesia and pain control make recovering from knee replacement surgery easier.

For some patients, knee replacement is an outpatient procedure — they have surgery in the morning and go home later that same day. Others will generally spend one night in the hospital.

For some patients, knee replacement is an outpatient procedure — they have surgery in the morning and go home later that same day.RUNSTUDIO / Getty Images

The knee replacement surgery recovery timeline

Lajam tells her patients that for the first two weeks they won’t like her very much, then they start getting motion back, getting around and seeing the pain dissipate. “The first two weeks is the toughest part, then it starts getting better,” she said. Severe pain after knee replacement surgery can be managed with medication.

Physical therapy can help you recover after knee replacement surgery. It improves your range of motion, reduces swelling and helps you learn to walk again.

“Bending one’s knee on one’s own is difficult — it’s helpful to have someone help you,” Lajam said. She said her patients typically have in-home physical therapy a couple of times a week, with instructions on exercises after knee replacement surgery to do on their own. And after the first few weeks, most people switch to outpatient physical therapy.

Lajam says that your body tends to recover around the three-month mark. But your knee will continue to heal for more than a year after surgery.

Getting back to routines, driving and work

In four to six weeks a lot of your range of motion starts to come back. Most people return to driving after knee replacement surgery and managing their daily routines and errands in one to two months, Wang said.

While Al Roker was back on the job two weeks after knee replacement surgery, most people need about six weeks, and people with more physical jobs may need three months.

Living with a knee replacement

Are you asking, “What can I expect after knee replacement surgery?” Here’s what to know about managing a knee replacement over the long term.

People want to know how long a knee replacement usually lasts. “It’s like asking how long a car lasts — you have to look at probabilities,” Wang said. He tells his patients it’s likely their implants will last 20 to 30 years.

If you’re more active you can potentially shorten the life of your implant. But you might've decided to have the implant so you could get back to what you love doing.kolderal / Getty Images

Can you run after knee replacement surgery?

Like any mechanical device, your knee replacement will wear out sooner if you put more stress on it. Wang says some surgeons want their patients to avoid running or high-impact activities.

“I don’t necessarily mind patients trying to get back to what they loved,” Wang said. If you’re more active you can potentially shorten the life of your implant. But you might've decided to have the implant so you could get back to what you love doing.

Springer said some people ask, “Can I wear a brace after knee replacement surgery?” He said most people don’t, but it’s fine if you want to. He added that people who ski or play tennis sometimes like to wear one as a reminder.

Stay connected with your surgeon

Lajam asks her patients to come in for an x-ray, or at least call and check in, every year or two for life. “Mechanical pieces can fail, or you could trip or fall and knock something loose and damage it and make it wear faster,” she said.

If your implant gets worn or damaged, you can consider a revision knee replacement surgery. What’s a revision knee replacement surgery? It’s a procedure to replace some or all of the artificial joint if it becomes damaged or worn. Surgeons can replace just the plastic piece if that’s what’s needed, or the entire implant if the damage is more severe.