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 Elie Mansour, MD, a Yale Medicine orthopaedic surgeon who specializes in knee and hip replacement and reconstruction, about the kinds of exercises patients should do after knee replacement surgery and how it can benefit their recovery.

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.

“Patients are expected to start moving their prosthetic knee and walking on the day of surgery under supervision of the physical therapy team or nursing staff,” Dr. Mansour says. “While it may sound difficult to achieve or painful, a nerve block and pain medications will help achieve this important milestone.”

A walker is generally recommended immediately following a knee replacement. The transition to a cane or unassisted walking depends on the patient’s strength, balance, and functional status after surgery, he adds.

While discharge to home after surgery is generally preferred, you need to be able to walk independently and have someone at home to support you before that can happen. To get you ready, you’ll see a physical therapist regularly for the duration of your hospital stay and continue with sessions after discharge.

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.

“Outpatient physical therapy is preferred as that allows access to more equipment that can help toward a faster recovery,” Dr. Mansour says.

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 and hamstrings, 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.

While the quads are the primary muscle requiring strengthening following total knee replacement, comprehensive strengthening should also include the hamstrings, glutes, hip abductors, and calf muscles to optimize overall lower extremity function and gait pattern.

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.

“Gaining range of motion is paramount for patient satisfaction after total knee replacement,” Dr. Mansour says. “Strategies include early initiation of passive, active assistive, and active range of motion exercises, combined with muscle strengthening.”

These exercises might include simple leg extensions to bend and straighten the knee while sitting in a chair.

“By two weeks after surgery, your benchmarks are approximately 80 degrees of active knee flexion and 100 degrees by seven weeks,” Dr. Mansour says.

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.

“While there is no specific restrictions following total knee replacement for range of motion, patients need to be aware that improvement of range of motion is progressive, and takes up to one year to plateau,” Dr. Mansour says.

Exactly when you can resume your regular physical activities 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, you’ll get cleared to return to some or all the physical activity you did before surgery.

“Most patients can resume low-impact activities like walking, swimming, and cycling within three to six months after surgery,” Dr. Mansour says. “High impact activities are delayed beyond six months and recommendations on this remain controversial and require an individualized approach. Most patients transition to low-impact activities following total knee replacement.”