How Exercises After Knee Replacement Surgery Can Speed Your Recovery
If you’re considering knee replacement surgery, it’s important to understand what to expect during recovery. Physical movement and exercise—some with a physical therapist and some on your own—are critical parts of recovery from knee replacement surgery. But you need certain types of exercise to ensure that you achieve a full range of motion with the new joint and to teach your body how to move and balance post-surgery.
We spoke with Jennifer Hankenson, MD, a Yale Medicine physiatrist (a physical medicine and rehabilitation physician), about the kinds of exercises patients should do after knee replacement surgery and how it can benefit their recovery.
What is knee replacement surgery?
Knee replacement surgery, or arthroplasty, is a surgical procedure that replaces a damaged, worn, or diseased knee joint with an artificial one to relieve pain and enhance function. This procedure is usually recommended for patients with severe arthritis or knee injuries that haven't improved with conservative treatments.
When do you start walking after knee replacement surgery?
“Most surgeons like patients to get up and start walking around the day of surgery to really jumpstart their recovery,” says Dr. Hankenson. “While it may sound painful, you’ll have lots of support.”
For starters, Dr. Hankenson says, your pain medication or nerve block should keep your pain well-controlled while you are in the hospital and the days after. You can also expect to have an assistive device to lean on. “For a single knee replacement, a cane may be all you need,” says Dr. Hankenson. “For a double, you might be on a walker.”
What does physical therapy (PT) for a knee replacement surgery involve?
You’ll see a physical therapist regularly for the duration of your hospital stay and continue with sessions after discharge.
What that looks like will depend on your mobility immediately after surgery. “Meaning, if you were to go directly home, would you be able, for example, to walk to the bathroom without help?” asks Dr. Hankenson.
Before discharge, you and your care team will decide the best course of action. Your options, based on insurance coverage, may include:
- Transfer to an in-patient rehabilitation facility, where you’ll have physical therapy every day to help speed your recovery and get you ready to move on your own at home.
- Physical therapy at home with a therapist who comes to you.
- Physical therapy at an outpatient center that you go to for each session.
There’s no right or wrong way to do it, Dr. Hankenson says, but if you have a choice between at-home and outpatient PT, “the benefit of the outpatient therapy for knee replacement surgery is that you have access to the equipment. When they’re coming to your home, they can bring some equipment, but you won’t have access to a full gym.”
No matter which route you take, once you’re discharged from the hospital, you’ll have about three 30- to 60-minute PT sessions per week for at least a few weeks. You’ll also be instructed to do PT exercises on your own or with a caregiver on the in-between days, says Dr. Hankenson.
“If you’re getting better, you may go less frequently, or if you’re doing really well, your therapist may say you can continue your exercises at home on your own and stop formal sessions after several weeks,” she says.
What kind of exercises will you do after knee replacement surgery?
After knee replacement surgery, each exercise you do in PT and on your own will help you achieve one or more of the following goals:
- Regain your balance on your new knee
- Strengthen your quadriceps, which help stabilize the knee joint
- Increase the range of motion in your new knee
Regain balance
Balance exercises might include practicing balancing on one leg, standing on one leg with your eyes closed, walking heel to toe, and standing on one leg while tossing a ball to your therapist or a partner.
Strengthen your quads
Your quadriceps provide muscle power to your knees. But if you’ve been less mobile in the time leading up to your knee replacement, these large muscles that form your thighs may have lost some strength.
Restoring your quad strength will help with all aspects of your recovery, says Dr. Hankenson.
“This can help the knee range of motion by making it easier to extend the knee,” Dr. Hankenson says. “It can also improve pain control by distributing force over the knee joint, leading to an easier time walking.” Ultimately, she adds, stronger quads can “prevent future injury by strengthening the joint.”
One example of a quad-strengthening exercise is sitting or lying on the floor with your legs extended out. Then, you’ll contract, hold, and release the quad of the leg with the new joint by pressing the back of your knee into the floor.
Increase range of motion
Many exercises that work your quads also move you through the knee’s range of motion. After surgery, it’s critical that you work almost right away on achieving the new joint’s full range of motion.
“There’s a risk that if you’re not doing consistent exercises to improve that range of motion, your muscles and tendons can get stuck after surgery,” Dr. Hankenson says, “and that’s much harder to correct.”
These exercises might include simple leg extensions to bend and straighten the knee while sitting in a chair.
“By week seven, you should be able to flex your knee at least 120 degrees and fully straighten your knee.”
But there’s an important caveat. After surgery, you’ll have specific restrictions related to range of motion that depend on how your surgery was done and the type of equipment that was used. Typically, your physical therapist will be made aware of your restrictions, and you should never push past them. This could cause serious injury. Before you leave the hospital, make sure that you or a family member understands your range of motion restrictions, adds Dr. Hankenson.
When can I return to regular physical activity?
Exactly when depends on a lot of factors. At first, your therapist might instruct you to continue your PT exercises every day on your own. But at some point—maybe as soon as week seven, Dr. Hankenson says—you’ll get cleared to return to some or all of the physical activity you did before surgery.
“Most patients who were doing high-impact activities prior to knee replacement return to them,” she says.
In some cases, your care team might discuss the advantages of swapping out your previous high-impact routine, such as marathons and basketball, for lower-impact sports, including swimming and cycling.
“There may be benefits to lower-impact activities when it comes to the longevity of your knee replacement. Most importantly, if you have concerns about what you will be able to do, you should discuss this with your surgeon prior to your knee replacement,” says Dr. Hankenson.
