You have osteoarthritis in your knee and you’ve been scheduled to have your knee replaced. What does this entail? We have had several patients’ status post total knee arthroplasty (aka total knee replacement) that have had little knowledge of what comes next. This article is meant to help explain what you can expect after surgery.
The actual surgery is approximately one to two hours in duration. The surgeon removes the arthritic part of your femur (thigh bone) and tibia (shin bone) and cements a metal prosthetic knee joint (which may or may not include a new kneecap) to the bone. You end up with an 8-10” vertical incision spanning from the base of your thigh to the top of your shin. The surgeon will usually use staples to close the incision. Showering instructions vary by surgeon; waiting two weeks is the current acceptable time frame. Each surgeon uses a different type of dressing on the incision. The bandage will be removed before the staples are removed; those typically come out at approximately 3-weeks.
Then comes the rehabilitation portion. This can be anywhere from 6 weeks to 6 months or more. Everyone progresses differently here so do not compare your progress with your neighbor who had hers done last year!
Following your brief (2-3 day) hospital stay (where you will start exercises and walking in a walker the day after surgery), you will have a choice to go home and get home care physical therapy (PT) twice a week for about 40 minutes at a time, or go to a short-term rehab facility for anywhere from 7-14 days where you will get about 40 minutes of PT twice a day 6 days a week. Either way, you will have exercises to do an additional 2-3 times per day on your own. You will most likely still be using some type of assistive device (walker, crutches, cane) during this time.
The new Medicare guidelines are pushing total knee replacements out of home PT and rehab facilities sooner and getting them into outpatient PT as early as 2 weeks post-op. We typically see patients still using a walker or a cane at this point, but you will start to wean off of your assistive device as you progress in therapy and get stronger.
While you will be given prescription pain medication, you should only use it as long as you and your doctor feel it is necessary. Physical therapy, frequent home ice applications, and speaking to your doctor about over-the-counter medications are less addictive ways of managing your post-operative pain.
Once the staples are removed and the scabs have fallen off, you will want to start “working the scar”. Scar massage is an important part of rehabilitation. If the scar gets tight, this will hinder your range of motion and cause more pain. We recommend using aloe or cocoa butter on the incision and rubbing perpendicular to the scar for about 5 minutes a day to keep it loose and flexible.
In outpatient PT, you will start with very basic exercises that you will continue 2-3 times per day at home. These include quad sets, heel slides, straight leg raises, short arc quads, long arc quads, squats, and various stretches. You may even begin riding a stationary bike to promote flexibility.
Most people will have the most difficulty either bending or straightening the knee following surgery, but typically not both. It is much harder to regain full extension than it is to regain flexion.
You need 120° of flexion in your knee to comfortably ascend and descend stairs, as well as to sit in low seats (such as the toilet). The goal for extension range of motion is 0°, which is essentially completely straight.
Scar tissue restricts range of motion the most. Everyone develops scar tissue at different rates. Your physical therapist may use different manual techniques to try to loosen the scar tissue if it becomes problematic. If your scar tissue is excessive, your surgeon may perform a manipulation under anesthesia. This procedure is about 10-20 minutes long, and it requires you to go under anesthesia so that the surgeon can manipulate your knee without restriction. This is usually followed by PT for 5 consecutive days.
Don’t be surprised if your opposite knee starts to hurt a little more following your total knee replacement. This knee usually had taken the brunt of your weight before and for some time after surgery and it is common for it to be a little painful.
Most surgeons do not require you to go to physical therapy prior to your surgery. However, patients who are introduced to the exercises before surgery are stronger going into it, and therefore have improved post-operative recovery. You can request a physician’s order for physical therapy prior to surgery, where you will learn your pre- and post-operative exercise program. Remember, it is your right as the patient to choose which physical therapist you want to see!