
A total knee replacement, which is also referred to as a total knee arthroplasty, is a fairly invasive procedure and can result in a long recovery process. If you have severe arthritis or significant damage in one or both of your knees and have been told that you are a good candidate for a knee replacement, you are probably wondering how much pain to expect and how long it will take for you to fully recover. Unfortunately there are no clear cut answers, because every individual has a different pain threshold, and no one progresses at the exact same rate. However, there are a few phases through which you should expect to go after a knee replacement (listed below). Some people skip either phase 2a or 2b or both, depending on how quickly they recover, but everyone goes through phase 1 and most people go through phase 3.
PHASE 1 – Acute Care
The surgical procedure will most likely be performed in a hospital, where you will stay for about 3 or 4 days afterwards. During this time you will most likely be set up on a continuous passive motion (CPM) unit, which moves your leg back and forth from full knee extension into flexion and back into extension again. This prevents scar tissue build up and joint stiffness. You will also receive 1 to 2 daily sessions with a physical therapist to work on the following: range of motion (ROM) and light strengthening exercises, transfers (like going from sit to stand and getting in and out of bed), walking with a walker or a pair of crutches (depending on what your doctor has ordered), and possibly stairs. You may think that the day after surgery is too soon to be getting up and walking, but the truth is that it is critical for you to get out of bed and start using your artificial knee as soon as possible. At the end of your acute care hospital stay, you will be evaluated to determine whether you are safe to go straight home if you need to be transferred to a rehab facility.
PHASE 2a – Rehab
If you are not ready to return home after 4 days in acute care, you will be transferred to a rehab facility, where you will stay anywhere from 1 to 4 weeks, depending on the length of time it takes for you to meet your goals. During your stay in rehab you will receive either one hour of physical therapy and one hour of occupational therapy or two hours of just physical therapy (one morning session and one afternoon session) every day. The therapist will continue working towards optimal knee ROM, leg strength, and functional mobility. Most rehab facilities have a therapy gym, where you will do your exercises, practice performing transfers, and learn how to go up and down stairs with your new knee.
PHASE 2b – Home Physical Therapy
If it is determined that you are independent enough or have enough help/support from friends or family to be discharged from acute care straight to your home, you may receive several weeks of home physical therapy. You can also receive home PT after Rehab if you are not yet mobile enough to start outpatient physical therapy (phase 3). The therapist will usually visit you in your home 3 times a week to continue working on strength, ROM, and function. Once you meet your home PT goals and you are able to start driving again or you have someone reliable to drive you to your appointments, you will begin outpatient physical therapy.
PHASE 3 – Outpatient Physical Therapy
By the time you have reached this phase of rehab, you should be walking with just a cane or no assistive device at all unless you were walking with a walker before the surgery. If you were using no assistive devices before the surgery, one of the major goals towards which you will be working in outpatient physical therapy is weaning yourself off the cane. You will also be working towards achieving functional knee ROM and optimal strength during this phase, so your therapist will set a goals for each of those areas as well. You will be seen 2 to 3 times per week, depending on what your therapist determines is necessary based on your first evaluation, and your PT sessions will consist of manual therapy (hands on), strengthening and stretching exercises, and gait and balance training. You will also be issued a home exercise program, and your compliance with this program will largely determine the speed at which you progress. The length of this phase of rehab depends upon the time it takes for you reach your goals and maximize your function.
After you have been discharged from formal physical therapy, it is important for you to continue with your home exercise program because it could take anywhere from six months to a year for you to fully recover, and you can show progress for up to two years.