Rehabilitation Protocol After a Total Knee Replacement

If you have severe arthritis in your knee or knees, physical therapy can help. With the right therapy, you can reduce the pain and improve your knee's range of motion (ROM) and strength.

Sometimes the arthritis is too severe for nonsurgical treatments, though. If so, you may need a total knee replacement (TKR) to restore the function of your knee.

This surgery is usually done in extreme cases, when you have:

• Severe knee pain
• Limited motion
• Extreme difficulty walking

If you have had a TKR or are expecting to have one, you will need physical therapy after surgery. This will help you regain mobility.

A post-operative protocol is a guideline that your surgeon and physical therapist (PT) may follow. It ensures you are making progress after your knee surgery. 

The TKR protocol gives you and your PT a framework for building your rehabilitation program.

If you are expecting to have a TKR surgery, ask your surgeon if they have a post-operative protocol that you should follow. Your PT may also have one.

This article looks at a typical total knee replacement rehabilitation protocol, week by week.

Post-Op Days 1-2

When you wake up after your TKR surgery, your knee may be in a continuous passive motion (CPM) machine. This device helps gently and slowly bend and straighten your knee.

Settings on the CPM adjust the amount of motion at your knee joint. Your healthcare provider and PT can work with you to make sure the CPM machine is set properly.

A physical therapist may visit you in the hospital on the first day after your surgery. This person is called an acute care physical therapist. In that visit, your acute care PT may help you:

• Sit up in bed
• Get out of bed
• Start to walk

A standard walker or wheeled walker is often used after surgery. This device will give you extra support while you are walking.

Your acute care PT will also have you do knee exercises while you are in the hospital. These exercises help improve your knee ROM and strength. They also help keep your ankles and hips moving. This will make walking easier.

Simple exercises can help stop blood from pooling in your body. Examples include:

• Pumping your ankles
• Squeezing your buttocks

These exercises are important to help prevent a serious condition called deep vein thrombosis (DVT). This is when a blood clot blocks a large vein. You are particularly at risk if you are immobile for a long period of time, such as after surgery.

Post-Op Weeks 1-2

You should have improved functional mobility after two to three days in the hospital. At this point, you will be discharged to your home or to a sub-acute rehabilitation facility.

Sub-Acute Rehabilitation

If you still need nursing care or more intense rehabilitation, you may be moved to a sub-acute rehabilitation facility.

This is an inpatient center that will help you get to the point where you will be able to go home. Here, you will focus on improving knee ROM and strength.

Sub-acute rehabilitation lasts about one to two weeks. A typical day involves two sessions of physical therapy.

Your PT will help you improve your knee strength and ROM. You may continue with the CPM machine if your healthcare provider feels it will help.

Home and Outpatient Physical Therapy

If you are sent home, you may choose to have a home care PT visit you. This option is usually for people who can't travel to an outpatient physical therapy center.

Scar tissue will form as your incision heals. Your PT may use gentle scar tissue massage and mobilization to help improve the mobility of your incision. This can help the skin and other tissues around your knee move more freely.

If you can travel to a physical therapy center, you may begin outpatient physical therapy. There, you will keep improving your knee ROM. You should be able to bend your knee to a 90 degree angle by the end of week 2.

Post-Op Weeks 3-6

You should be working in an outpatient physical therapy center by the third week.

Your therapy will include more aggressive ROM exercises. These should continue to help you improve your knee motion. By the end of week six, your knee motion should be about 100 to 105 degrees.

You may benefit from riding a stationary bicycle after TKR surgery. Your PT will help you find the right seat height.

Don't be surprised if you can't pedal all the way around when you first start. Keep working the pedals forward and backward. As your ROM improves, you should be able to fully pedal the bike.

You will keep doing exercises that build strength in your knee. Your PT will also teach you exercises to improve the strength of other muscles, including your:

• Quadriceps
• Hamstrings
• Hip muscles

Simple straight leg raising exercises will help you build these muscles. As your strength improves, you may add cuff weights to your lower leg or ankle.

Your PT may also use neuromuscular electrical stimulation (NMES). This will help your quadriceps contract and improve your ability to use these muscles on your own.

During this time, you may still use ice to help control pain and swelling around your knee joint. Sometimes swelling persists for many weeks after TKR surgery.

Post-Op Weeks 7-8

During the final two weeks of your rehabilitation, you should be working with your PT to maximize your functional mobility. Exercises will focus on gaining strength in the muscles around your knee and leg.

You may do more advanced balance exercises. You may also use a BAPS board. This is a device that can help you improve your balance. It can also help you improve your proprioception, which is your ability to sense your body's position in space.

During this time, you should move on to walking without an assistive device. Your pain should be under control.

As you get close to the end of your rehabilitation, ask your PT about how to keep up your exercise program. A fitness center with stationary bicycles and weight training equipment can help you maintain mobility and strength after TKR surgery.

Summary

Physical therapy after total knee replacement can help you regain your mobility.

In the first day or two after surgery, an acute physical therapist will help you get out of your hospital bed. You will start to walk using an assistive device.

After you leave the hospital, you will continue therapy at home or in a physical therapy center. You should be able to bend your knee 90 degrees at the end of the second week.

Physical therapy will continue to focus on improving strength and mobility. During weeks three through six, you should move from using a walker to using a cane. 

By the end of the eighth week, your pain should be under control. You should be able to walk without an assistive device.

A Word From Verywell

Remember that every person is different. Many factors help determine your outcome after TKR surgery.

A week-by-week protocol is a general framework of what to expect after surgery. Still, your own progression may be faster or slower.

Work closely with your healthcare provider and PT to ensure that your TKR rehabilitation is successful.