If your knee is severely damaged by arthritis or injury, it may be hard for you to perform simple activities such as walking or climbing stairs. You may even begin to feel pain while you are sitting or lying down.
If medications, changing your activity level, and using walking supports are no longer helpful, you may want to consider total knee replacement surgery. By resurfacing the damaged and worn surfaces of the knee can relieve pain, correct leg deformity and help resume normal activities.
The knee is the largest joint in the body. Normal knee function is required to perform most everyday activities. The knee is made up of the lower end of the thighbone (femur), which rotates on the upper end of the shin bone (tibia), and the kneecap (patella), which slides in a groove on the end of the femur. Large ligaments attach to the femur and tibia to provide stability. The long thigh muscles give the knee strength.
The joint surfaces where these three bones touch are covered with articular cartilage, a smooth substance that cushions the bones and enables them to move easily.
All remaining surfaces of the knee are covered by a thin, smooth tissue liner called the synovial membrane. This membrane releases a special fluid that lubricates the knee, reducing friction to nearly zero in a healthy knee.
Normally, all of these components work in harmony. But disease or injury can disrupt this harmony, resulting in pain, muscle weakness, and reduced function.
Common Causes of Knee Pain and Loss of Knee Function
The most common cause of chronic knee pain and disability is arthritis. Osteoarthritis, rheumatoid arthritis, and traumatic arthritis are the most common forms.
Osteoarthritis usually occurs in people 50 years of age and older and often in individuals with a family history of arthritis. The cartilage that cushions the bones of the knee softens and wears away. The bones then rub against one another, causing knee pain and stiffness.
Rheumatoid arthritis is a disease in which the synovial membrane becomes thickened and inflamed, producing too much synovial fluid that overfills the joint space. This chronic inflammation can damage the cartilage and eventually cause cartilage loss, pain, and stiffness.
Traumatic arthritis can follow a serious knee injury. A knee fracture or severe tears of the knee ligaments may damage the articular cartilage over time, causing knee pain and limiting knee function.
Is Total Knee Replacement for You?
Whether to have total knee replacement surgery should be a cooperative decision made by you, your family, your family physician, and your orthopaedic surgeon. Your physician may refer you to an orthopaedic surgeon for a thorough evaluation to determine if you could benefit from this surgery. Alternatives to traditional total knee replacement surgery that your orthopaedic surgeon may discuss with you include a unicompartmental knee replacement or a minimally invasive knee replacement.
Reasons that you may benefit from total knee replacement commonly include
Medical Evaluation :
If you decide to have total knee replacement surgery, you may be asked to have a complete physical examination by your physician before surgery to assess your health and to identify any conditions that could interfere with your surgery.
Several tests may be needed to help plan your surgery:
Preparing Your Skin and Leg
Your knee and leg should not have any skin infections or irritation.
Tell us about the medications you are taking. We will tell you which medications you should stop taking and which you should continue to take before surgery.
Although the incidence of infection after knee replacement is very low, an infection can occur if bacteria enter your bloodstream. Treatment of significant dental diseases (including tooth extractions and periodontal work) should be considered before your total knee replacement surgery.
A preoperative urological evaluation should be considered for individuals with a history of recent or frequent urinary infections. For older men with prostate disease, required treatment should be considered prior to knee replacement surgery.
The following is a list of modifications that can make your home easier to navigate during your recovery:
You will most likely be admitted to the hospital on the day of your surgery. After admission, you will be evaluated by a member of the anesthesia team. We prefer spinal or epidural anesthesia, in which you are awake but your legs are anesthetized.The procedure itself takes approximately 2 hours. The damaged cartilage and bone will be removed and then the new joint is fixed to restore the alignment and function of your knee.
Many different types of designs and materials are currently used in total knee replacement surgery, nearly all of which consist of three components: the femoral component (made of a highly polished strong metal), the tibial component (made of a durable plastic often held in a metal tray/made of metal), and the patellar component (also plastic).
After surgery, you will be moved to the recovery room, where you will remain for 1 to 2 hours while your recovery from anesthesia is monitored. After you awaken, you will be taken to your hospital room.
Unicompartmental Knee Replacement
Although not as common as total knee replacement, the partial or unicompartmental knee replacement (commonly called the "uni") is a viable alternative in limited situations. The designs of the unicompartmental types of knee replacements have improved over the years, as has the sophistication of the instruments used to implant these types of artificial joints. The unicompartmental knee replacement also has smaller, less invasive incisions.
The unicompartmental knee replacement is used to replace a single compartment of the arthritic knee. The knee joint has three compartments: the medial (inner) compartment, the lateral (outer) compartment, and the patellofemoral (kneecap) compartment. If the damage is limited to either the medial or lateral compartment, that compartment may be replaced with the unicompartmental knee implant.
If two or more compartments are damaged, unicompartmental knee replacement may not be the best option. Unicompartmental knee replacement is also less desirable for a young, active person because it may not withstand the extremes of stress that high levels of activity create. It is best suited for the older, slim person with a relatively sedentary lifestyle. Only between 6 and 8 out of 100 patients with arthritic knees are good candidates for unicompartmental knee replacement.
Because the unicompartmental knee replacement can be inserted through a relatively small incision (approximately 3 to 4 inches long), which does not interrupt the main muscle controlling the knee, rehabilitation is faster, hospitalization is shorter, and return to normal activities is more rapid than after a total knee replacement.
However, this is still a serious surgical procedure, and has all of the same risks as total knee replacement. These risks, as well as whether you are a good candidate for unicompartmental knee replacement, should be discussed with your orthopaedic surgeon.
Minimally Invasive Knee Replacement
A recent advance in the performance of total knee replacement is the use of minimally invasive surgical approaches. This technique, still in its relative infancy, is more challenging than standard total knee replacement. The incisions are approximately half the size of those used in a standard approach. The smaller incisions and new techniques to expose the joint may result in short-term advantages such as a quicker rehabilitation, less pain, and a shorter hospitalization, according to some reports.
The minimally invasive approach to the total knee replacement is appropriate for non-obese patients who have reasonable motion without significant deformity. Hospitalization may be reduced to 1 to 3 days among these patients, and the need for an extended stay for inpatient rehabilitation may be reduced or eliminated in most patients.
Your Stay in the Hospital
You will most likely stay in the hospital for 3 to 5 days. After surgery, you will be pain free.Cont. epidural infusion will be given for that as pain management is an important part of your recovery. Walking and knee movement are important to your recovery and will begin immediately after your surgery.
To avoid lung congestion after surgery, you should breathe deeply and cough frequently to clear your lungs.
Foot and ankle movement also is encouraged immediately following surgery to increase blood flow in your leg muscles to help prevent leg swelling and blood clots. Most patients begin exercising their knee the day 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.
The complication rate following total knee replacement is low. Serious complications, such as a knee joint infection, occur in fewer than 2% of patients. .
Blood clots in the leg veins are the most common complication of knee replacement surgery. a prevention program, which may include periodic elevation of your legs, lower leg exercises to increase circulation, support stockings, and medication to thin your blood is planed.
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 the wound has thoroughly sealed and dried. The wound may be bandaged 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 promote proper tissue healing and to restore muscle strength.
Exercise is a critical component of home care, particularly during the first few weeks after surgery. You should be able to resume most normal activities of daily living within 3 to 6 weeks following surgery. Some pain with activity and at night is common for several weeks after surgery. Your activity program should include:
Driving usually begins when your knee bends sufficiently so you can enter and sit comfortably in your car and when your muscle control provides adequate reaction time for braking and acceleration. Most individuals resume driving approximately 4 to 6 weeks after surgery.
Warning signs of possible blood clots in your leg include:
Warning signs that a blood clot has traveled to your lung include:
Notify your doctor immediately if you develop any of these signs.
The most common causes of infection following total knee replacement surgery are from bacteria that enter the bloodstream during dental procedures, urinary tract infections, or skin infections. These bacteria can lodge around your knee replacement and cause an infection.
After your knee replacement, you must take preventive antibiotics before dental or surgical procedures that could allow bacteria to enter your bloodstream.
Warning signs of a possible knee replacement infection are:
Notify your doctor immediately if you develop any of these signs.
A fall during the first few weeks after surgery can damage your new knee and may result in a need for further surgery. Stairs are a particular hazard until your knee is strong and mobile. You should use a cane, crutches, a walker, or hand rails or have someone to help you until you have improved your balance, flexibility, and strength.
Your surgeon and physical therapist will help you decide what assistive aides will be required following surgery and when those aides can safely be discontinued.
How Your New Knee Is Different
You may feel some numbness in the skin around your incision. You also may feel some stiffness, particularly with excessive bending activities. Improvement of knee motion is a goal of total knee replacement, but restoration of full motion is uncommon. The motion of your knee replacement after surgery is predicted by the motion of your knee prior to surgery. Most patients can expect to be able to almost fully straighten the replaced knee and to bend the knee sufficiently to climb stairs and get in and out of a car. Kneeling is usually uncomfortable, but it is not harmful. Occasionally, you may feel some soft clicking of the metal and plastic with knee bending or walking. These differences often diminish with time and most patients find them to be tolerable when compared with the pain and limited function they experienced prior to surgery.
Your new knee may activate metal detectors required for security in airports and some buildings. Tell the security agent about your knee replacement if the alarm is activated.
After surgery, make sure you also do the following: