ARTHROPLASTY, KNEE

General Information

DEFINITION--Arthro = joint; plasty = surgical shaping or alteration of. Surgery on an injured or diseased knee to re-establish a movable joint.

BODY PARTS INVOLVED--Knee joint; muscles, ligaments, bones, cartilage and bursa forming the knee joint.

REASONS FOR SURGERY--Diseased or injured knee causing chronic pain or disability impairing the quality of life.

SURGICAL RISK INCREASES WITH

• Obesity; smoking.
• Excess alcohol consumption.
• Recent or chronic illness.
• Use of mind-altering drugs, including: narcotics; psychedelics; hallucinogens; marijuana; sedatives; hypnotics; or cocaine.

What To Expect

WHO OPERATES--Orthopedic surgeon.

WHERE PERFORMED--Hospital.

DIAGNOSTIC TESTS

• Before surgery: General history; physical examination; x-rays of joint; joint aspiration (to check for active infection); blood and urine studies.
• During surgery: X-rays.
• After surgery: X-rays.

ANESTHESIA--General anesthesia by injection and inhalation with an airway tube placed in the windpipe.

DESCRIPTION OF OPERATION

• An incision is made into the affected knee.
• The arthritic or diseased surfaces of the femoral condyles and tibial plateau are removed.
• The above areas are replaced by durable prosthetic components that are fixed firmly in place with a special form of bone cement.
• The new knee joint may be hinged (for unstable knees) or unhinged.
• The joint is put into a cast.

POSSIBLE COMPLICATIONS

• Excessive bleeding; blood clots.
• Surgical-wound infection.
• Pneumonia.
• Loosening of joint components at a future time.

AVERAGE HOSPITAL STAY--0 to 1 day.

PROBABLE OUTCOME--Expect complete healing without complications. Allow about 6 weeks for recovery from surgery.

Postoperative Care

† Buy and use self-help devices, such as a raised toilet seat, bath bench and long--

handled grippers, to limit hip bending.

• Use handrails and wear low shoes. > Learn and abide by your safe range of motion. > Cough and deep breathe as instructed. > A hard ridge should form along the incision. As it heals, the ridge will recede gradually. > Bathe and shower as usual. You may wash the incision gently with mild unscented soap. > Use an electric heating pad, a heat lamp or a warm compress to relieve incisional pain. > Move and elevate legs often while resting in bed to decrease the likelihood of deep-vein blood clots. > Use crutches or a cane to walk until your doctor determines that healing is complete. > Physical therapy may hasten healing and restore strength. Ask your doctor.

† You may use non--prescription drugs, such as acetaminophen, for minor pain. Avoid aspirin.

ACTIVITY

• As prescribed and directed by your surgeon and physical therapist.
• Avoid very active sports such as tennis, skiing or contact sports.

DIET

• No special diet.
• Vitamin and mineral supplements (sometimes).

Call Your Doctor If

† Pain, swelling, redness, drainage or bleeding increases in the surgical area.

• You develop signs of infection: headache, muscle aches, dizziness or a general ill feeling and fever.