Total Knee Replacement or TKR is the most common type of knee surgery. In this type, both sides of the knee joint are replaced. The patient experiences less pain and improved mobility. Scar tissues may make it challenging to move and/or bend the knees.
The goal of total knee replacement surgery is to relieve knee pain and increase knee function by resurfacing the bones that meet at the knee joint. The surgeon removes damaged portions of bone at the end of the femur (thigh-bone) and top of the tibia (shin-bone) and replaces them with prosthetic components. Some surgeries also resurface the back of the patella, or kneecap.
Below is a step-by-step description of a typical total knee replacement surgery By Pritish Kumar Halder. The actual surgery typically lasts for 2 hours per knee.
Is Total Knee Replacement for You?
The decision to have total knee replacement surgery should be a cooperative one between you, your family, your primary care doctor, and your orthopaedic surgeon. Your doctor may refer you to an orthopaedic surgeon for a thorough evaluation to determine if you might benefit from this surgery.
When Surgery Is Recommended?
There are several reasons why your doctor may recommend knee replacement surgery. People who benefit from total knee replacement often have:
- Severe knee pain or stiffness that limits everyday activities, including walking, climbing stairs, and getting in and out of chairs. It may be hard to walk more than a few blocks without significant pain and it may be necessary to use a cane or walker
- Moderate or severe knee pain while resting, either day or night
- Chronic knee inflammation and swelling that does not improve with rest or medications
- Knee deformity — a bowing in or out of the knee
- Failure to substantially improve with other treatments such as anti-inflammatory medications, cortisone injections, lubricating injections, physical therapy, or other surgeries.
The Orthopaedic Evaluation
An evaluation with an orthopaedic surgeon consists of several components:
- Medical history.Your orthopaedic surgeon will gather information about your general health and ask you about the extent of your knee pain and your ability to function.
- Physical examination.This will assess knee motion, stability, strength, and overall leg alignment.
- X-rays.These images help to determine the extent of damage and deformity in your knee.
- Other tests.Occasionally blood tests or advanced imaging, such as a magnetic resonance imaging (MRI) scan, may be needed to determine the condition of the bone and soft tissues of your knee.
A knee replacement (also called knee arthroplasty) might be more accurately termed a knee “resurfacing” because only the surface of the bones are replaced.
There are four basic steps to a knee replacement procedure:
- Prepare the bone. The damaged cartilage surfaces at the ends of the femur and tibia are removed along with a small amount of underlying bone.
- Position the metal implants. The removed cartilage and bone is replaced with metal components that recreate the surface of the joint. These metal parts may be cemented or “press-fit” into the bone.
- Resurface the patella. The undersurface of the patella (kneecap) is cut and resurfaced with a plastic button. Some surgeons do not resurface the patella, depending upon the case.
- Insert a spacer. A medical-grade plastic spacer is inserted between the metal components to create a smooth gliding surface.
Recovery at hospital
If you are admitted to the hospital, you will most likely stay from one to three days.
After surgery, you will feel some pain. This is a natural part of the healing process. Your doctor and nurses will work to reduce your pain, which can help you recover from surgery faster. Medications are often prescribed for short-term pain relief after surgery.
Be aware that although opioids help relieve pain after surgery, they are a narcotic and can be addictive. As soon as your pain begins to improve, stop taking opioids. Talk to your doctor if your pain has not begun to improve within a few days of your surgery.
Blood Clot Prevention
Your orthopaedic surgeon may prescribe one or more measures to prevent blood clots and decrease leg swelling. These may include special support hose, inflatable leg coverings (compression boots), and blood thinners. Foot and ankle movement is also encouraged immediately following surgery to increase blood flow in your leg muscles to help prevent leg swelling and blood clots.
Most patients can begin exercising their knee hours after surgery. A physical therapist will teach you specific exercises to strengthen your leg and restore knee movement to allow walking and other normal daily activities soon after your surgery.
To restore movement in your knee and leg, your surgeon may use a knee support that slowly moves your knee while you are in bed. The device is called a continuous passive motion (CPM) exercise machine.
It is common for patients to have shallow breathing in the early postoperative period. This is usually due to the effects of anesthesia, pain medications, and increased time spent in bed. This shallow breathing can lead to a partial collapse of the lungs (termed “atelectasis”), which can make patients susceptible to pneumonia. Your nurse may provide a simple breathing apparatus called a spirometer to encourage you to take deep breaths.
Recovery at Home
You will have stitches or staples running along your wound or a suture beneath your skin on the front of your knee. The stitches or staples will be removed several weeks after surgery. A suture beneath your skin will not require removal.
Avoid soaking the wound in water until it has thoroughly sealed and dried. You may continue to bandage the wound to prevent irritation from clothing or support stockings.
Some loss of appetite is common for several weeks after surgery. A balanced diet, often with an iron supplement, is important to help your wound heal and to restore muscle strength.
Exercise is a critical component of home care, particularly during the first few weeks after surgery.
Your activity program should include:
- A graduated walking program to slowly increase your mobility, initially in your home and later outside
- Resuming other normal household activities, such as sitting, standing, and climbing stairs
Specific exercises several times a day to restore movement and strengthen your knee.