This procedure restores function to a severely damaged knee. Most commonly, it is used to repair a knee that has been damaged by arthritis. During the procedure, the surgeon replaces the damaged portions of the knee with artificial parts. These parts consist of a metal femoral component, a metal tibial component and a plastic spacer. A small plastic patellar component may also be used.
Introduction: A total knee replacement—is one of the most commonly performed joint replacement procedures in the United States. On average, over a million are performed each year. A total knee replacement helps to relieve pain, improve range of motion and restore overall function allowing you to return to the activities that you enjoy participating in.
History of Injury: This surgery is commonly performed to alleviate the pain that is caused by normal “wear and tear” of the cartilage (i.e. osteoarthritis), inflammatory arthritis such as Rheumatoid arthritis, or due to arthritis that develops as a result of previous trauma.
Diagnosis: Your orthopedic surgeon will discuss your health history and perform a physical exam. They will routinely take X-rays, to allow them to assess the overall status of your bones and cartilage. This provides important information that your surgeon may use to determine the best treatment for you. Further imaging may be required, such as an MRI, however, this is on a patient specific basis.
Treatment Options: The first line of treatment for knee pain is physical therapy and the use of anti-inflammatory medications such as Aleve or Ibuprofen. If this fails to alleviate symptoms, the next step is to try injections in the knee which consist of either a corticosteroid or a viscosupplementation. Patients are encouraged to use an ambulatory assistance device such as a cane or walker. Weight loss is always encouraged for patients who are overweight or obese. If all non-operative measures fail to improve your symptoms, you can have a discussion with your orthopedic surgeon regarding a total knee replacement.
Preoperative Evaluation: If you are deemed a candidate for a total knee replacement and you elect to proceed, you will have to make an appointment with your primary care doctor to be evaluated prior to surgery. They will order certain blood work and counsel you on which medications you need to continue or stop prior to surgery. It is also recommended that you undergo a teeth cleaning within 6 months of your surgery.
Surgery: A total knee replacement is performed either under general anesthesia or spinal anesthesia based upon the preference of your orthopedic surgeon. An incision is made on the front of the knee to expose the damaged ends of the femur and tibia. The bone is then shaped to hold an artificial joint made of a combination of metal and plastic. The undersurface of the kneecap may also be cut and resurfaced, and finally, a plastic spacer is placed between the components so they can move and glide easily. In a knee replacement, you still retain your native muscles, tendons and some ligaments.
Post-Operation: You will go to a recovery room while your anesthesia wears off, and you will be monitored. Once the effects of anesthesia wear off, you will get up and start working with physical therapy. After surgery, you will be able to bear your full weight on the knee that you had surgery on. Physical therapy will focus on range of motion exercises, strengthening the muscles around the knee and to gait training. You will initially be using an ambulatory assistance device (such as a walker or cane) and you will gradually wean off this as you tolerate.
Activity Restrictions: After undergoing a knee replacement surgery, patients are typically encouraged to refrain from high impact activities such as running or jumping. Activities such as hiking, biking, elliptical, couples’ tennis, golf and bowling are allowed.
Risks and Complications: As with any surgery, there is a risk of infection or blood clots. Patients will be put on a blood thinner after surgery for a few weeks at the discretion of the surgeon to decrease the risk of a blood clot. Sometimes, the range of motion after surgery may be more limited than was expected which may be due to scar tissue that builds up around the knee. Additionally, over time, implant surfaces will wear and there may come a time where a revision surgery is required. Annual follow up is recommend with your orthopedic surgeon following surgery.
Summary: You should seek out an experienced orthopedic surgeon to perform your total knee replacement. This clinician should not only be skilled at performing the surgery, but should also be knowledgeable about choosing patients who are appropriate for the procedure.