What is Knee Replacement Surgery?

A knee replacement surgery is a surgical procedure of resurfacing the damaged knee from arthritis. The ends of the bone that form the knee joint are capped together with metal and plastic parts and the kneecap.

Types of arthritis affecting the knee

• Osteoarthritis – primarily affecting middle-aged and older people, is a degenerative joint disease that may result in the destruction of joint cartilage and nearby bone in the knees.
• Rheumatoid Arthritis – There will be an inflammation of the synovial membrane which will result in an increase in synovial fluid, causing discomfort and stiffness.
• Traumatic arthritis – Is arthritis caused by any kind of injury.

The main target of knee replacement surgery is to restore the parts of the knee that have been damaged due to various types of arthritis and relieve the knee pain that other medical surgeries cannot control.

Knee Anatomy

The knee is nothing more than two long leg bones held together by muscles, ligaments, and tendons. Each of these bones’ ends is covered with a layer of cartilage to protect it from sudden shocks.

The knee consists of two sets of muscles, including the quadriceps muscles, which straighten the legs, and the hamstring muscles, which bend the leg at the knee. Tendons are the stiff connective tissues that connect muscles to bones. Ligaments are the elastic bands of tissues that connect a bone to a bone.

Parts of the knee

• Tibia – This is the more significant bone of the lower leg called the shin bone.
• Femur – Known as the upper leg bone or the thigh bone.
• Patella – Also known as the kneecap
• Cartilage – A tissue that covers the surface of a bone at a joint.
• Synovial membrane – A tissue that lines and seals the joint to form a joint capsule. To lubricate the joints, the synovial membrane secretes synovial fluid.
• Ligament – A tough, elastic connective tissue that surrounds the joint to give support and limits the joint’s movement.
• Tendon – A tough connective tissue that connects muscles to bones and helps control movement of the joint.
• Meniscus – This is a curved section of the cartilage that acts as a shock absorber.

Reasons to go through with the procedure

The surgery is mainly to relieve the knee from any kind of pain that cannot be controlled with any other kind of treatments. Osteoarthritis is the most common condition that needs to be treated with a knee replacement surgery.

The degradation of cartilage causes osteoarthritis. The damage caused to the bones and cartilages limits the motion and might cause pain. People suffering from severe degenerative joint disease may be unable to perform certain normal activities like bending the knee, climbing up the stairs, since they’re painful.

Other types of arthritis, such as rheumatoid arthritis and arthritis caused by a knee injury, can cause knee joint deterioration. Furthermore, fractures, torn cartilage, and/or torn ligaments may result in irreparable knee joint injury.

If a few medical treatments don’t seem to be enough knee replacement surgery is the next best option to be considered. Some of the medical treatments for such degenerative joint disease are:

• Anti-inflammatory medications
• Pain medications
• Limiting painful activities
• Assistive devices for walking
• Physical therapy
• Cortisone injections into the knee joint
• Viscosupplementation injections
• Weight loss

Risks involved with knee replacement surgery

Like any other medical surgery, the knee replacement surgery can also have its own complications. A few of which may include,

• Bleeding
• Infection
• Blood clots in the legs
• Loosening or wearing out of the prosthesis
• Fracture
• Continued pain or stiffness

The replaced joint might become loose, or get dislodged, and in turn giving way to another replacement surgery in the future. The nerves and the blood vessels may get injured in the area of the surgery resulting in weakness. The joint pain due to this cannot be cured with any surgery.

Preparing for the procedure

• You will be explained the process of the procedure and made comfortable. You will also be given the chance to ask questions about the procedure and make sure you’re completely fine with the proceedings ahead.
• The doctor will require you to undergo a comprehensive physical examination of your body before the treatment to ensure that you do not have any current issues. Several blood tests and diagnostic tests will be administered to you.
• Inform your doctor about any drug, latex, or anaesthetic agent allergies you may have.
• Let the doctor know all the medications that you are taking presently before the procedure.
• You should let the doctor know if you are pregnant or suspect that you might be.
• You will be advised by your doctor to fast for 8 hours, preferably during the midnight.
• A sedative will be given to you before the procedure.
• You might also be introduced to a physical therapist to consult about rehabilitation prior to the surgery.
• Make sure there is someone at home to take care of the chores for a couple of weeks after you are discharged.

At the time of the procedure

Generally a knee replacement surgery will require you to stay at the hospital. The procedure may vary depending on your condition and your doctor’s practices.

Generally, knee replacement surgery follows this process:

• You will be asked to remove your clothing and will be given a gown to wear.
• It is possible that a urinary catheter will be inserted.
• The excess hair at the surgical site will be chopped off.
• An anesthesiologist will constantly keep monitoring your heart rate, blood pressure, blood oxygen level, and breathing throughout the procedure.
• An antiseptic solution will be used to clean the skin around the surgery site.
• An incision in the knee area will be made by the surgeon.
• The damaged surfaces of the knee joint will be replaced with prosthesis, made of metal and plastic, by the doctor. Cemented prosthesis is the most common type of prosthesis found.
• With surgical stitches, the incision will be closed after the procedure.
• The fluid from the surgical site will be removed with the help of a drain.
• It will later be covered with a sterile dressing.

Patients with total knee replacements may require a second procedure years later, although it is uncommon. The second surgery may be required due to loosening, fracture, or other issues with the restored joint. Reoperations are often less successful than original surgeries and are fraught with problems. Future replacement technologies and approaches will result in better patient outcomes and fewer problems.