is knee joint replacement?
Knee joint replacement is a procedure that involves
replacing an injured or ailing knee with an artificial joint, or prosthesis.
The prosthesis is made of metal alloys, plastics, and
polymers. It mimics the function of a knee. According to the American Academy of
Orthopaedic Surgeons (AAOS), replacement knees can fit your needs and
specifications. When selecting a prosthetic knee, your doctor will take into
- activity level
- overall health
The procedure to remove your old knee and replace it with a
prosthesis usually takes less than two hours, but recovery and rehabilitation
can last months.
Another name for this procedure is knee arthroplasty. Knee
replacements are a very common surgery. The AAOS notes that more
than 600,000 knee replacements occur every year in the United States.
is the purpose of a knee joint replacement?
Damage from arthritis is the most common reason for knee
joint replacement. This includes both osteoarthritis and rheumatoid arthritis.
Doctors usually only recommend knee replacement after other,
less invasive treatments have failed. First-line treatment options include:
- weight loss
- physical therapy
- assistive devices, such as a cane or a knee
Key factors in determining if you’re a good candidate for
knee joint replacement include:
- how much your knee pain interferes with daily
activities, such as walking or climbing stairs
- if your knee is deformed, bows, or “blows out”
- your age
- your overall health
Knee surgery is a typical treatment for people over the age
of 55. Younger people who have their knees replaced may outlive their
artificial knees and may need a revision.
Doctors evaluate each candidate for knee replacement surgery
on an individual basis.
do you prepare for knee joint replacement?
Before surgery, your doctor will assess your overall health
and anesthesia risks. This evaluation will include:
- a full medical history
- a physical examination
- blood tests
- other imaging tests
Your doctor will ask you for your complete medical history,
including any prior surgeries and ongoing health conditions you have. Tell your
doctor about any medication you’re taking including over-the-counter medicines
and nutritional supplements. You may have to stop taking some or all of them
before your surgery.
Also, tell your doctor if you’ve ever had an allergic
reaction to anesthesia. Your doctor will review your anesthesia options based
on your preferences and what they think is appropriate for your situation. This
could include general anesthesia, which means you’re asleep during surgery. Or,
you may receive anesthesia in your spine, which leaves you awake but pain-free
from the waist down.
Your doctor will give your surgeon the results of your
medical evaluation, medical history, and your anesthesia choice.
You can expect to walk with the aid of crutches or a walker
for several weeks. Before surgery, you should prepare your home to accommodate
- You may need to install handles in showers and
around the toilet.
- It’s good to have a chair and footrest available
so you can elevate your leg.
- If possible, keep your living space on the first
floor if you have a multistory house.
Your doctor and surgical team will give you full
instructions on how to best prepare for surgery. It’s important to follow those
instructions as closely as possible.
happens during knee joint replacement?
When it’s time for your surgery, you’ll change into a
hospital gown and get an IV to provide you with fluids and nutrients during the
surgery. Just before surgery, you’ll receive anesthesia.
During the procedure, which lasts between one and two hours,
your surgeon will make a long surgical cut above your knee. With the skin and
muscle pulled back, they’ll cut away damaged cartilage and bone.
They’ll affix the new knee joint to your femur, or
thighbone, and tibia, which is the main bone in your lower leg. They’ll do this
using specialized cement, pins, and screws. Afterward, your surgeon will close
the incision wound with stitches and apply a bandage.
You’ll recover from the surgery in a special recovery room
where a team can monitor your vital signs.
happens after knee joint replacement?
After surgery, your leg will feel stiff. You’ll experience
some pain. Receiving painkillers through your vein, or intravenously, can help
manage this pain. You may receive long-acting local anesthetics at the time of
surgery or possibly a nerve block to help with postoperative pain. You’ll also receive
medication to prevent your blood from clotting.
Most people begin physical therapy the day of surgery or day
after their surgery to promote blood flow to the tissues around the new knee.
Your surgeon may recommend using a continuous passive-motion machine. This is a
special brace-like device that continuously moves your knee in a gentle bending
Your surgeon will let you know when it’s best to leave the
hospital. This is based on the results of the surgery and your condition.
Following your surgery, you’ll undergo considerable physical
therapy. Your surgeon and physical therapy team will design a program that’s
right for you.
are the complications associated with knee joint replacement?
Every medical procedure carries the risk of bleeding, blood
clots, and infection. Your doctor will explain these risks and what you can do
to minimize them. The AAOS states that less than 2 percent
of the more than 600,000 people who have total knee replacements each year in
the United States have serious complications.
Complications associated with knee replacement surgery
- the artificial knee wearing out over time
- blood clots in the leg or lungs
- breathing problems caused by the anesthesia
- a heart attack
- knee stiffness
- nerve damage in the knee
- a stroke
Contact your doctor immediately if you experience the
- drainage from your surgical scar
- a fever over 100°F (37.8°C)
- increasing pain, redness, swelling, and
tenderness in the knee
Infection is an ongoing concern for people who receive
artificial joints. As bacteria and other contaminants regularly flow through
your blood, they can infect your artificial knee. If you have a knee infection,
your doctor may have to remove part of or the whole artificial knee to treat the
infection before they can implant one again.