Total Knee Arthroplasty

A knee that becomes damaged by arthritis or injury creates a situation where even the simplest of activities, such as walking or climbing stairs, become overly difficult. Sometimes you might even feel sharp and/or dull pains when sitting or laying down.

If the nonsurgical treatments suggested by your doctor prove to be ineffective, you may need to consider total knee replacement surgery. Though it sounds daunting, joint replacement surgery is a safe and effective way to relieve pain, correct deformities of the leg, and help you get your life back to normal.

Since first being performed in the late 1960s, improvements in surgical materials and techniques have made an already effective procedure even more effective than it was before. In fact, total knee replacements are known to be one of the most successful procedures in all of medicine. According to the Agency for Healthcare Research and Quality, more than half a million knee replacement surgeries are performed on an annual basis in the US.

Whether you are simply pondering the idea of knee replacement surgery or have already decided to go forward with that option, this article serves the purpose of helping you understand everything there is to know about this procedure.

 

Description

A knee replacement is referred to in the medical world as a knee arthroplasty, and is sometimes referred to as knee “resurfacing” because you are actually only having the surface of the bones replaced.

There are four steps involved in a knee replacement procedure:

  • Preparation of the bone—damaged cartilage surfaces at the ends of the femur and tibia are removed along with a bit of the underlying bone.
  • Positioning of the implants—The removed cartilage and bone is replaced with metal components that replicate the original surface of the joint. These parts will either be cemented or “press-fit” into the bone.
  • Resurfacing of the patella—The underside of the patella, or kneecap, is cut and resurfaced with what can best be described as plastic button. It should be noted that not all knee replacements require this step.
  • Insertion of a spacer—a medical-grade plastic spacer is placed between the metal components to create a smooth gliding surface, which will in turn allow you to move freely after surgery.

Your Surgery

Anesthesia

Once you are at the hospital, you will be greeted by a member of the anesthesia team, who will discuss with you the anesthesia options. The two most common types of anesthesia are general anesthesia, where you are put to sleep, and spinal, epidural, or regional nerve block anesthesia, where you are awake but your body is numb from the waist down. You will have already discussed with your doctor these different options and, with your input, the best option will be chosen for you.

Procedure

In total, the procedure will take roughly one to two hours. The orthopedic surgeon will first remove cartilage and bone that has been damaged, then position the new plastic and metal implants in order to restore the alignment and function of your knee. Once surgery has been completed, you will move to a recovery room where your recovery from the effects of anesthesia will be closely monitored. Once you have woken up, you will be transported back to your hospital room or to physical therapy.

Your Recovery at Home

Whether you believe it or not, the ultimate success of your surgery will depend upon how well you follow the instructions given to you by your doctor for when you are at home.

Wound Care

You will have stitches or staples running along your wound on the front of your knee. While some sutures do not require any removal, staples will be removed a few weeks after surgery, once the doctor has confirmed you are healing properly.

You must be sure to avoid soaking the wound in water until it has thoroughly sealed and dried. Continual bandaging of your wound will also be required. This may mean changing bandages several times a day at first.

Diet

It is common for patients who have undergone knee replacement to experience a loss of appetite for a few weeks following the surgery. A balanced diet, sometimes supported with an iron supplement, is important in assisting your wound’s healing process and restoring muscular strength.

Activity

Exercise is actually very important during the first few weeks after surgery when you are at home. In most cases, normal daily living activities can be resumed shortly after your procedure. Pain in and around your knee is common and will last for a few weeks to several months.

Your at-home activity schedule should include the following:

  • A walking program that will increase your mobility over time. First inside, then outside.
  • Slowly and carefully resuming normal household activities such as sitting, standing, and climbing stairs.
  • Specific exercises that are to be performed several times a day to restore movement and strengthen your knee. Most can perform these exercises with little to no help, however some people may need the assistance of a physical therapist for a few weeks.

When it comes to driving a car, this is something that will be permitted only so long as your knee bends enough that you can enter into and sit comfortably within your car. What’s more, your muscles must be in good enough shape so that you can both brake and use the gas pedal without any strain. You must also be done using strong pain medications that can alter your judgement and reaction time. It usually takes about a month to six weeks before people can begin driving.

Outcomes

 

How Your New Knee Is Different

The end goal of any knee replacement is to improve the function of your knee. Though most people hope to return to normal after their surgery, full restoration of motion is not common. Most times, the motion you will have after your surgery can be accurately predicted based on the extent of motion you had prior to having surgery. Most people will be able to fully straighten their replaced knee and bend enough to climb stairs and enter/exit a car. Kneeling may feel uncomfortable, but is ultimately harmless.

There are frequent reports of a feeling of numbness around the site of your incision. Some also complain of stiffness after bending their knee frequently.

After surgery, some patients report the feeling or sound of clicking in the knee, caused by the metal and plastic components moving about. This is normal. These small clicks and pops are due to the mechanical components and are more annoying than they are painful or restrictive.

It is important to note that your new knee may activate metal detectors at airports and other places. Be sure to alert security of this before the alarm is activated. It is also recommended that you take oral antibiotics prior to any future dental appointments to significantly reduce the risk of infection.