What You Should Know About Total Knee Replacement Surgery

Why the number of knee replacements in the U.S. is rising

Total knee replacement, X-rays
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If you need total knee replacement surgery, you're not alone. Every year in the United States, more than 300,000 knee replacements are performed, a number expected to increase 525 percent by the year 2030, according to Time magazine. First performed in 1968, total knee replacement is one of the top orthopedic surgical advances of the 20th century. 

The knee replacement prosthesis consists of three components: femoral (metal), tibial (plastic in a metal tray), and patellar (plastic).

The prosthesis replaces your damaged knee joint.

Who Needs a Total Knee Replacement?

Normal knee function is necessary to perform almost all of the usual daily activities. Your knee allows you to walk, bend, kneel, and squat.

If your knee has been injured or hurts because of arthritis, you will find it difficult to perform routine activities. Osteoarthritis, rheumatoid arthritis, and traumatic arthritis are the three most common types of arthritis that affect the knee joint.

Typically, arthritis patients first try conservative treatments to control knee pain and slow joint damage. If the conservative treatments (medications, injections, braces, physical therapy, heat) are not effective and do not produce a satisfactory response, many patients consider knee replacement as their last-resort treatment option.

The decision to have knee replacement surgery should be made with your family, primary care physician, and orthopedic surgeon.

But, for now, consider if you have any of the following:

  • Severe knee pain that limits activities, such as walking, climbing stairs, getting in and out of chairs
  • Moderate to severe knee pain while resting during the day or night
  • Knee inflammation that is not helped by medications or rest
  • Knee deformity such as bowing in or out of the knee
  • Knee stiffness that makes it difficult to bend or straighten the knee
  • Unsatisfactory relief from NSAIDs (nonsteroidal anti-inflammatory drugs)
  • An intolerance to analgesic drugs (pain medications)
  • Unsatisfactory results from other conservative treatments tried

If you answered yes to most or all of the questions, you may be a candidate for knee replacement surgery.

How Are Patients Evaluated for Knee Replacement?

Most total knee replacement patients are 60 to 80 years old, but some patients are younger or older and do very well following surgery. Each patient must be evaluated to determine if knee replacement surgery is her best option.

Patients are evaluated based on their medical history. Physicians review information about the patient's general health, the extent of the knee pain, and the severity of physical limitation. A physical examination yields more information about the knee, including range of motion, stability, strength, alignment, and what movements provoke pain. X-rays and other imaging techniques are used to assess joint damage and deformity.

Are Your Expectations About Knee Replacement Realistic?

It's essential that patients considering knee replacement surgery understand what to expect from the procedure.

For instance, most patients opt for the surgery in hopes of pain relief and improved knee function. But that doesn't mean knee replacement surgery turns you into the Bionic Man. In fact, you will have restrictions after surgery, both temporary and long term. Also, knee replacements last for many years, but you may need revision surgery.

About 90 percent of knee replacement patients have a successful outcome following surgery. Patients typically report dramatic pain relief, and the ability to perform basic tasks they have not done easily for a long time. Surgeons will often make recommendations about your activity level after the knee replacement.

 They might expect you to do some recreational walking, swimming, golf, driving, light hiking, recreational biking, ballroom dancing, and normal stair climbing.

Activities that exceed the usual recommendations include vigorous walking or hiking, skiing, tennis, repetitive aerobic stair climbing, and repetitive lifting of over 50 pounds. So, take it easy post-surgery. Some activities are considered downright dangerous after surgery. They include jogging, running, contact sports, jumping sports, and high-impact aerobics. Don't even think about engaging in these activities.

Are You Prepared for Surgery?

Your orthopedic surgeon and his staff will guide you through their normal routine for knee replacement. They will assign you a surgery date and give you a schedule for what should be done prior to surgery. This includes checking medical insurance, pre-op testing, and autologous blood donation, if needed.

Once you've completed the pre-op tasks, you will be given information about what to expect during surgery. You will learn about your options for anesthesia, how long the surgery will take, how long you can expect to be in the hospital, and discharge planning.

After surgery or post-op, you will be given rehabilitation instructions or discharge instructions. You will be assessed by physical therapy, occupational therapy, and wound care officials. Plans will be made according to your needs, but the goal is to have you recover safely, fully, and without complications.

What Are Possible Complications of Knee Replacement?

The complication rate associated with knee replacement surgery is low with serious complications developing in fewer than 2 percent of patients. Joint infection is considered a serious complication of knee replacement.

The most common complication of knee replacement surgery is blood clots that form in leg veins. Preventative measures are taken to reduce the likelihood of blood clots: elevating legs exercises to promote circulation in the legs, compression stockings, and blood thinners.

Points to Remember About Knee Replacement

After having a knee replacement, be conscious of certain important aspects of your recovery:

  • Do your post-op exercises as instructed by your physical therapist.
  • Balance rest and activity, especially early in your recovery.
  • Follow instructions to prevent blood clots.
  • Know the signs of infection.
  • Be careful not to fall.
  • Adhere to your restrictions.

Sources:

Total Knee Replacement. American Academy of Orthopaedic Surgeons. August 2007.
http://orthoinfo.aaos.org/topic.cfm?topic=A00389

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