Total Knee Replacement (Arthroplasty)
What is a Total Knee Replacement (TKR)?
A total knee replacement (TKR) involves removing the ends of the bones at the knee joint (the tibia, sometimes called “shin bone”) and the femur (thigh bone) and replacing them with artificial parts. Replacement parts consist of a metal cap placed on the end of the femur and a plastic cap placed on the top of the shin bone. Sometimes, a plastic insert is used to replace the kneecap.
How Can a Physical Therapist Help?
Your physical therapist can help ensure that your TKR will be successful by providing evaluation and treatment before and after surgery.
How Can a Physical Therapist Help Before & After Surgery?
Before Your Surgery (“Pre-op Conditioning”)
The better physical shape you are in before TKR surgery, the better your results will be (especially in the short term). Before surgery, your physical therapist will teach you exercises and show you how you will walk with assistance after your operation. Your therapist also will discuss precautions and home adaptations, such as removing loose rugs or strategically placing a chair so that you can sit instead of squatting to get something out of a low cabinet. It’s always easier to make these modifications before you have TKR surgery.
If you smoke, quit! That may help improve your healing after surgery. If you are overweight, focus on weight loss prior to surgery. Losing excess body weight may help you recover more quickly, and help improve your function and overall results following surgery.
Immediately Following Your Surgery
With a TKR, you likely will stay in the hospital 2 or 3 days following your surgery. If you have other medical conditions, such as diabetes or heart disease, you might need to stay an additional few days. If you are like most patients, you will be told to put as much weight as comfortable, when standing, on the leg that had surgery. While you are in the hospital, a physical therapist will:
Show you how to practice walking with a walker or crutches
Teach you how to safely get in and out of bed or a chair
Help you continue to do the flexibility and strengthening exercises that you learned before your surgery
During this period, it’s especially important to control the swelling in your knee and to help your incision heal. Your physical therapist may perform electrical stimulation, where electrodes are placed on the skin to stimulate the nerves around the knee to help reduce pain and swelling and promote healing.
Your therapist also may apply cold to the knee to help decrease swelling and may recommend that you wear support stockings.
As You Begin to Recover
Proper rehabilitation after a TKR is essential to your recovery. Your physical therapist will help you regain much of your knee range of motion as soon as possible. At this point, you might be walking with a cane or with one crutch.
Your physical therapist can speed up (or “hasten”) your return to activity and help make your new knee better than the old one! Your therapist will tailor range-of-motion exercises, progressive muscle-strengthening exercises, body awareness and balance training, and activity-specific training to your specific needs.
Occasional swelling of the knee joint and lower leg can occur for up to 3 months after surgery. To relieve swelling, you can wear support stockings, apply a cold pack, and elevate your lower leg on a pillow when sitting or lying down.
Range-of-motion exercises. Swelling and pain can make you move your knee less. Your physical therapist can teach you safe and effective exercises to restore the range of motion to your knee so that you can perform your daily activities.
Strengthening exercises. Weakness of the muscles of the thigh and lower leg could make you need to use a cane when walking. Your physical therapist can determine which strengthening exercises are right for you, with the goal of no longer needing to use a cane to walk.
Body awareness and balance training. Specialized training exercises help your muscles “learn” to respond to changes in your world, such as uneven sidewalks or rocky ground. When you are able to put your full weight on your knee without pain, your physical therapist may add agility exercises (exercises that have you practice making quick stops and starts, turns, and changes in direction) and activities using a balance board that challenge your balance and knee control. Your program will be based on the physical therapist’s examination of your knee, on your goals, and on your activity level and general health.
Functional training. When you can walk freely without pain, your physical therapist may begin to add activities that you were doing before your knee pain started to limit you. These might include community-based actions such as crossing a busy street or getting on and off an escalator. Your program will be based on the physical therapist’s examination of your knee, on your goals, and on your activity level and general health.
The timeline for returning to leisure or sports activities varies from person to person; your therapist will be able to estimate yours based on your specific condition.
Activity-specific training. Depending on the requirements of your job or the type of sports you play, you might need additional rehabilitation that is tailored to your job activities (such as climbing a ladder) or sport activities (such as swinging a golf club) and the demands that they place on your knee. A physical therapist can develop a rehabilitation program that takes all of these demands into account.
Can this Injury or Condition be Prevented?
If you have knee pain, you may be able to delay the need for surgery by working with a physical therapist to improve the strength and flexibility of the muscles that support and move the knee. This training could even help you avoid surgery altogether. Participating in an exercise program designed by a physical therapist can be one of your best protections against knee injury. And staying physically active in moderately intense physical activities and controlling your weight through proper diet might help reduce the risk of osteoarthritis of the knee getting worse.
Real Life Experiences
Carmella is a 67-year-old grandmother of 3 who has had osteoarthritis in her right knee for many years. She used to take care of her grandchildren after school each day before her daughter got home from work. Then Carmella’s knee became so painful that she could no longer walk up and down stairs or stand for long periods of time. She also had a lot of difficulty getting up from a chair. She had to tell her daughter that she couldn’t take care of her grandchildren anymore. Carmella decided it was time to receive a total knee replacement. Her surgery was successful and had no complications.
The first day after her surgery:
A physical therapist came to Carmela’s room in the hospital and began teaching her deep-breathing exercises to help her improve her breathing after surgery. The therapist also showed her how to bend and straighten her knee, and how to to tense and then relax and release her knee, calf, and hip muscles to strengthen them. The therapist then helped Carmella practice sitting and standing at the edge of her hospital bed, and to begin bending and straightening her new knee joint.
The second day after surgery:
Carmella started walking with crutches with the therapist’s assistance, putting a little weight on her right leg. The therapist also instructed her in some gentle leg-strengthening exercises.
The third day after surgery:
Since Carmella was able to walk without the therapist’s aid in the hospital hallways and up and down a few stairs, she was allowed to return home with her crutches. Her therapist designed an at-home exercise program just for her, and taught it to her.
Once Carmella returned home, a home care physical therapist regularly visited her at her house to continue her rehabilitation.
The therapist prescribed more challenging exercises for Carmella that added weights for strengthening. Carmella also began to practice walking with a cane instead of her crutches.
About 12 weeks after her surgery:
Carmella felt hardly any pain in her knee. She could walk without using a cane, but she still needed to use a handrail when going up or down the stairs. At times, her knee felt “shaky.” She still could not take care of her grandchildren because of these remaining challenges.
Carmela’s therapist instructed her in more aggressive strengthening and movement exercises for her hips, knees, and ankles. The therapist also worked with her on improving her stair climbing, her balance, and her agility. After 6 weeks (12 physical therapy sessions), Carmella felt confident walking up and down the stairs, getting in and out of her car and driving, and performing other daily activities. She felt that her new knee was much more stable.
Later that month, Carmella was able to take care of her grandchildren again. She also joined a health club that offered exercise programs for older adults so she could maintain the benefits she had gained from her physical therapy.