Knee Replacement

A knee replacement is major surgery and requires specialized care before, during and after the procedure. Surgeons at MaineHealth provide high quality and safe care for patients having a knee replacement.

What is a knee replacement?

During knee replacement surgery, the surgeon removes arthritic and damaged bone in the knee joint, resurfaces the remaining bone and implants a replacement knee joint.

  • With a total knee replacement, damaged cartilage and bone is removed from the surface of your knee joint and replaced with an artificial surface made of metal and/or plastic.
  • In a partial knee replacement, the surgeon only replaces one part of your knee joint.

The replacement joint, called a prosthetic joint, is made of plastic and metal and is specially selected by the surgeon to match the build of a patient's body.

Will a knee replacement help me?

The most common cause of chronic knee pain and disability is arthritis. Patients with arthritis in the knee joint experience pain when the smooth cartilage at the end of the bones is damaged or worn down. Surgery relieves severe, disabling pain and may restore the knee's ability to work properly. Some reasons that a knee replacement may be recommended include:

  • Severe knee pain or stiffness that limits your everyday activities
  • Difficulty walking short distances without significant pain; may need to use a cane or walker
  • Moderate or severe knee pain at rest
  • Chronic knee inflammation and swelling that does not improve with rest or medications
  • Knee deformity/bowing
  • Failure to substantially improve with other treatments, such as anti-inflammatory medications, cortisone injections, lubricating injections, physical therapy or other surgeries.

Orthopedic surgeons evaluate patients to decide if knee replacement is right for them. Recommendations for surgery are based on a patient's pain and disability, not age.

Knee replacement evaluation

The decision to have a knee replacement requires an evaluation by an orthopedic surgeon, who will determine if surgery is right for you. The evaluation may include:

  • Medical history to collect information about health condition and to determine the severity of knee pain and function
  • A physical exam to assess knee motion, stability, strength and overall leg alignment
  • X-rays to see damage and deformity in your knee
  • Blood tests
  • Magnetic resonance imaging (MRI) to view the condition of the bone and soft tissues of the knee.

Total knee replacements have been performed successfully at all ages. There is not a definitive age or weight restriction for knee replacement surgery.


Knee replacement surgery risks

Risks associated with knee replacement include:

  • Blood clots in legs

  • Urinary tract infection

  • Nausea and vomiting, usually related to pain medication

  • Pain and stiffness in the knee

  • Bleeding into the knee joint

  • Nerve damage

  • Blood vessel injury

  • Infection

  • Failure of the artificial joint

As with any surgery, a knee replacement procedure has risks related to the surgery and post-surgery.

Knee replacement recovery

A well-designed recovery plan is critical to the success of a knee replacement. Recovery for knee replacement usually includes:

  • Pain medication to reduce inflammation and swelling

  • Blood clot prevention

  • Physical therapy to learn specific knee exercises to regain strength and restore movement

  • Wound care

  • Balanced diet to help wound healing and restore muscle strength

  • Instructions about home safety and tips for making daily routines easier at home