Total Knee Replacement:
What to Expect if You Choose Surgery...
More than 90 percent of individuals who undergo total knee replacement surgery experience a dramatic reduction of knee pain and a significant improvement in the ability to perform daily activities. Following surgery, you will be advised to avoid some types of activity, including jogging and high impact sports. With normal use and activity, every knee replacement develops some wear in its plastic cushion. Excessive activity or weight may accelerate this normal wear and cause the knee replacement to loosen and become painful. With appropriate activity modification, knee replacements can last for many years.
Getting Ready for Knee Replacement Surgery
- Medical Evaluation
If you decide to have total knee replacement surgery, you may be asked to have a complete physical by your family physician several weeks before surgery to assess your health and to rule out any conditions that could interfere with your surgery.
Several tests such as blood samples, a cardiogram and a urine sample-may be needed to help your orthopedic surgeon plan your surgery.
- Preparing Your Skin and Leg
Your knee and leg should not have any skin infections or irritation. Your lower leg should not have any chronic swelling. Contact your orthopedic surgeon prior to surgery if either of these conditions is present for a program to best prepare your skin for surgery.
- Blood Donation
You may be advised to donate your own blood prior to the surgery. It will be stored in the event you need blood after your surgery.
Tell your orthopedic surgeon about the medications you are taking. You may be instructed to discontinue use of certain ones before surgery.
- Dental Evaluation
Although the incidence of infection after knee replacement is very low, an infection can occur if bacteria enter the bloodstream. Treatment of significant dental diseases (including tooth extractions and periodontal work) should be considered before your total knee replacement surgery.
- Urinary Evaluations
A preoperative urological evaluation should be considered for individuals with a history of recent or frequent urinary infections. For older men with prostate disease, treatment should be considered prior to knee replacement surgery.
- Social Planning
Though you will be able to walk on crutches or a walker soon after surgery, you will need help for several weeks with such tasks as cooking, shopping, bathing and doing laundry. If you live alone, your surgeon's office and a social worker or a discharge planner at the hospital can help you make advance arrangements to have someone assist you at home. They also can help you arrange for a short stay in an extended care facility during your recovery, if this option works best for you.
- Home Planning
Several suggestions can make your home easier to navigate during your recovery. Consider these options:
- Safety bars or a secure handrail in the shower or bath:
- Secure handrails along stairways
- A stable chair with a sturdy seat cushion (height of 18-20 inches), a firm back, two arms, and a footstool for intermittent leg elevation
- A toilet seat riser with arms, if you have a low toilet
- A stable shower bench or chair for bathing
- Removing all loose carpets and cords
- A temporary living space on the same floor, walking up or down stairs will be more difficult during early recovery
Your Knee Replacement Surgery
Day of Surgery
You will most likely be admitted to the hospital on the day of your surgery. After admission, you will be evaluated to determine what type of anesthesia is be best for you. The most common types of anesthesia are general anesthesia, in which you are asleep throughout the procedure, and spinal or epidural anesthesia, in which you are awake but your legs are anesthetized.
The procedure takes about two hours. Your orthopedic surgeon will remove the damaged cartilage and bone and then position the new metal and plastic joint surfaces to restore the alignment and function of the knee.
Many types of designs and materials are currently used in total knee replacement surgery. Most of them 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), and the patellar component (also plastic).
The complication rate following total knee replacement is low. Serious complications, such as a knee joint infection, occur in less than 2 percent of patients. Major medical complications such as heart attack or stroke occur even less frequently. Chronic illnesses may increase the potential for complications. Although uncommon, when these complications occur, they can prolong or limit your full recovery. Blood clots in the leg veins are the most common complication of knee replacement surgery. Your orthopedic surgeon will outline 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. Although implant designs and materials as well as surgical techniques have been optimized, wear of the bearing surfaces or loosening of the components may occur. Additionally, although an average of 115 degrees of motion is generally anticipated after surgery, scarring of the knee can occasionally occur and motion may be more limited. This is particularly true in patients with limited motion before surgery. Finally, while rare, injury to the nerves or blood vessels around the knee can occur during surgery.
After surgery, you will be moved to the recovery room, where you will remain up to two hours while your recovery from anesthesia is monitored. After you awaken, you will be taken to your hospital room.
In the Hospital
One of the highest risks for complications associated with joint replacement surgery is the danger of patients falling after surgery.
"Patients who have joint replacement surgery have typically experienced significant pain for prolonged periods of time. When they wake up post-operatively, they are suddenly pain-free due to the anesthesia and pain medication used in their operations and post-operativley,” said Kim Beekmann, R.N., CJRI’s executive director. “When they first try to stand, they often find themselves very unsteady.”
From pre-operative classes through surgical preparations, CJRI staff stress to patients that regardless of their age or condition, they are at risk to fall following surgery.
“When patients come in for their surgery, we partner with them and family members by asking them to sign a pledge stating that they are aware that they are at risk of falling and that they will promise to give us a call anytime they need to mobilize — getting in or out of bed, a chair or the bathroom, so we can assist them,” Ms. Beekmann said. Patients are reminded of this pledge by staff at eight-hour intervals following surgery and through a message on the communication boards in their rooms that reads: Call — Don’t Fall.
In a further step to prevent patient falls, the beds on CJRI’s post-operative units are equipped with special monitors. "The beds are weight-activated so that if a certain percentage of the patient’s weight is lifted off the bed, it will trigger an alarm at the nursing station so that staff can come to make sure they have the assistance they need,” Ms. Beekmann said.
The success of your surgery also will depend on how well you follow your orthopedic surgeon's instructions at home during the first few weeks after surgery.
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 days to 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 up to several weeks after surgery. A balanced diet, often with an iron supplement, is important to promote proper tissue healing and restore muscle strength.
Exercise is a critical component of home care, particularly during the first few weeks after surgery, and your active participation will affect the long-term results. You should be able to resume most normal activities of daily living within three to six weeks following surgery. Some pain with activity and at night is common for several weeks after surgery.
Your activity program should include:
- A graduated walking program to slowly increase mobility
- Resuming other normal household activities, such as sitting and standing and walking up and down stairs
- Specific exercises several times a day to restore movement and strengthen the knee. A physical therapist can help you at home or in a therapy center the first few weeks after surgery.
- Driving once your knee bends sufficiently. Most patients resume driving about four to six weeks after surgery.
Staying Healthy after Knee Replacement
Blood Clot Prevention - Follow your orthopedic surgeon's instructions carefully to minimize the potential of blood clots that can occur during the first several weeks of your recovery.
Warning signs of possible blood clots in your leg include:
- Increasing pain in your calf
- Tenderness above or below your knee
- Increasing swelling in your calf, ankle and foot
If you are experiencing any of the above symptoms, go to the emergency room immediately.
Warning signs that a blood clot has traveled to your lung include:
- Sudden increased shortness of breath
- Sudden onset of chest pain
- Localized chest pain with coughing
If you are experiencing any of the above symptoms, go to the emergency room immediately.
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 surgical site and cause infection.
For the first two years after your knee replacement, you must take preventive antibiotics before dental or surgical procedures that could allow bacteria to enter your bloodstream. After two years, talk to your orthopedist and your dentist or urologist to see if you still need preventive antibiotics before any scheduled procedures.
Warning signs of a possible knee replacement infection are:
- Persistent fever (higher than 100 degrees)
- Increasing redness, tenderness or swelling of the knee wound
- Drainage from the knee wound
- Increasing knee pain with both activity and rest
If you are experiencing any of these symptoms, call your surgeon.
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, hand rails or someone to help you until you have improved your balance, flexibility, and strength.
Your "New" Knee
It is normal to feel some numbness in the skin around the incision. You may also 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 depends on the motion of your knee prior to surgery. Most patients can expect to nearly fully straighten the replaced knee and to bend the knee sufficiently to go up and down stairs and get in and out of a car. Kneeling is sometimes 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. Your new knee may activate metal detectors required for security in airports and some buildings.