Knee Replacement Surgery

Knee 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. Knee replacement involves removing parts of the bones that make up the knee joint and replacing them with artificial implants. It is primarily used to treat osteoarthritis-related knee pain and stiffness.

The majority of persons who have this surgery have advanced knee arthritis, in which the cartilage in the knee is worn away and the surface has become pitted, degraded, and uneven. However, pain, stiffness, instability, and a shift in body alignment are all symptoms of this condition. Some persons who have a weaker knee joint due to an injury or another ailment can benefit from knee replacement surgery.

While selecting a prosthetic knee, your doctor will take into account your:

• age
• weight
• activity level
• overall health

Types of Knee Replacement Surgery

1. Total Knee Replacement Surgery: A type of surgery where the entire joint is replaced with aritificial surfaces.

Surgical Procedure

Traditional total knee replacement involves a 7-8 incision over the knee, a hospital stay of 3-5 days, and a recovery period (during which the patient walks with a walker or cane) typically lasting from one to three months. The large majority of patients report substantial or complete relief of their arthritic symptoms once they have recovered from a total knee replacement.

• Partial Knee Replacement Surgery:  A type of surgery where only one damaged compartment of the knee is replaced.

Surgical Procedure

Partial knee replacements have been around for decades and offer excellent clinical results, just like total knee replacements. Less invasive techniques are available to insert these smaller implants but only a minority of knee replacement patients (about 10%) are good candidates for this procedure.

Why Is Knee Replacement Surgery Performed?

The most common reason for knee replacement surgery is to repair joint damage caused by osteoarthritis or rheumatoid arthritis. People who need knee replacement surgery usually have problems walking, climbing stairs, and getting in and out of chairs. They may also experience moderate or severe knee pain at rest. The primary reason for undergoing knee replacement surgery is to improve the function of the knee joint and to alleviate joint pain.

Common reasons for undergoing Knee Replacement includes:

• Osteoarthritis

Osteoarthritis occurs in the people with age above 50 years. This caused because of the main wear and tear of the knee joint.

• Rheumatoid Arthritis

We also know Rheumatoid Arthritis as Inflammatory Arthritis. When the membrane around the knee joint become thick and inflamed, it causes Rheumatoid Arthritis.

• Post-Traumatic Arthritis

Post-Traumatic Arthritis causes when there is a severe injury around the knee joint like ligament tear or knee break.

Kabera Care doctors may recommend total knee replacement surgery if you are suffering from any of the following signs of knee joint dysfunction:

• Knee pain that does not go away, even with medication
• Constant pain throughout the day, even while resting
• Limited range of motion in the knee joint
• Stiffness and swelling
• Difficulty standing for long periods of time
• Inability or difficulty with usual physical activities, such as walking or climbing stairs
• Little or no improvement in knee function following conservative treatments

How is a Knee Replacement Performed?

Surgical procedures differ depending on the patient’s needs and the surgeon’s approach, but generally the steps are as follows:

1. The patient’s vital signs are checked to make sure blood pressure, heart rate, body temperature, and oxygenation levels are normal and surgery can proceed. A mark is made on the knee undergoing surgery.

• Peripheral nerve blocks may be offered by the anesthesia team to aid with early postoperative pain control while allowing muscles to function safely and effectively during physical therapy. The procedure involves injecting numbing medication with ultrasound needle guidance for safe and effective placement around a portion of the femoral nerve. These versatile procedures can be performed before and/or after the surgery. They can also include either a one-time injection lasting 24 to 36 hours or placement of a catheter for repeat infusions over several days.

• Anesthesia is administered. The patient may receive:

• General anesthesia (be put to sleep)
• A spinal nerve block, which will block sensation from the waist down, along with a relaxant

The type of anesthesia a patient receives is usually decided well ahead of time, but may be modified on the day of surgery based on a discussion between the patient and the anesthesiologist.

• The surgeon makes an incision down the center of the knee about 8 to 10 inches long, and then cuts through deeper tissue, including the quadriceps tendon, and flips over the kneecap to access the femur and tibia. (If performing minimally invasive knee replacement, the surgeon will make smaller incisions and use minimally invasive surgical techniques.)

• To improve the surgeon’s ability to access to the joint, the knee is bent to 90 degrees.

• The surgeon uses a bone saw to remove the arthritically damaged areas at bottom of the femur and the top of the tibia. Each bone is reshaped to exactly fit its new prosthesis. Because these cuts must be precise, the surgeon uses either a metal jig or computer assistance to line up the cuts.

• A surgeon may resurface the back of the kneecap, or patella, and attach an implant. A polyethylene component may be attached to facilitate the patella’s gliding against the new joint. Research has not shown a significant difference in outcomes for patients who received patella resurfacing and those who did not.1,2 Components are attached to the femur, tibia, and-if applicable-the patella. Typically, these components are affixed using fast-drying bone cement. Cementless components, which allow bone tissue to grow on them and adhere over time, also exist.

• A flexible cushion, usually made of polyethylene, is attached on top of the new tibia surfaces. This spacer acts as a shock absorber between the two new prosthetic surfaces.

• The leg is flexed and extended to test the fit of the components and the new knee’s range of motion.

1. The surgeon straightens the knee to allow the components, cement, and bone to bond together.

1. The surgeon will repair any deep tissue that was cut during surgery and then stitch the skin at the incision.

1. After surgery, a patient may be taken to a recovery room for a few hours while the surgical anesthesia wears off. Afterwards a patient will be seen by a physical therapist, and if deemed appropriate, could be discharged home on the day of surgery. If the patient is not deemed safe for discharge on the day of surgery, they will be admitted to a hospital room where he or she will spend 1 to 2 days before being discharged.

Recovering from Surgery

After the procedure, the patient can expect to be given antibiotics for about a day after surgery and medication (anticoagulants) to control pain and prevent blood clots. A drain to stop fluid from building up around the knee may be inserted.

Some people may have a urinary catheter to minimize the need to stand after the procedure. To help retain flexibility and range of motion, some surgeons recommend a continuous passive motion machine (CPM) that slowly bends and straightens the knee joint while keeping it supported.

FACT

While each individual is different, short-term recovery is usually between 2 and 3 months. After this time, people can typically walk without an aid or use over-the-counter pain medications instead of stronger prescription medications. Long-term recovery takes about six to 12 months.

For most people, the knee is sufficiently healed after long-term recovery, and they can resume normal activities. The time it takes to recover enough to return to work depends on the individual and their job.

A person who works in an office and spends most of their day sitting at a desk can probably return to work sooner.

If the job is more physically demanding, doctors may recommend more healing time before returning to work.

Managing knee pain following surgery is important for a good recovery, and doctors will give advice on controlling and living with any discomfort. Recovery also involves physical therapy and a home exercise routine to strengthen the joint and ensure that the knee’s range of motion is as good as it can be.

Results

• In most of the cases, after the knee replacement surgery, the patients get relief from the knee pain, have a better walking ability and improved quality of life.

• Around 1 to 2 months after the surgery, the patient is able to return to all normal routine activities.

• The patient is fit to drive a car after a month.

• After the recovery is complete, the patient is allowed to perform low-impact activities e.g. swimming, walking, biking or golfing. However, the doctor advises not to perform any strenuous activities e.g. jogging, weight lifting, running, etc.

• It is always better to consult a doctor regarding the restrictions or limitations in performing any activity.