Knee replacement, also called knee arthroplasty or total knee replacement, is a surgical procedure to resurface a knee damaged by arthritis. Metal and plastic parts are used to cap the ends of the bones that form the knee joint, along with the kneecap. This surgery may be considered for someone who has severe arthritis or a severe knee injury.
Various types of arthritis may affect the knee joint. Osteoarthritis, a degenerative joint disease that affects mostly middle-aged and older adults, may cause the breakdown of joint cartilage and adjacent bone in the knees. Rheumatoid arthritis, which causes inflammation of the synovial membrane and results in excessive synovial fluid, can lead to pain and stiffness. Traumatic arthritis, arthritis due to injury, may cause damage to the cartilage of the knee.
The goal of knee replacement surgery is to resurface the parts of the knee joint that have been damaged and to relieve knee pain that cannot be controlled by other treatments.
Want to know more about Knee Replacement Surgery. Read full article by Pritish Kumar Halder below:
Anatomy of the knee
Joints are the areas where 2 or more bones meet. Most joints are mobile, allowing the bones to move. Basically, the knee is 2 long leg bones held together by muscles, ligaments, and tendons. Each bone end is covered with a layer of cartilage that absorbs shock and protects the knee.
There are 2 groups of muscles involved in the knee, including the quadriceps muscles (located on the front of the thighs), which straighten the legs, and the hamstring muscles (located on the back of the thighs), which bend the leg at the knee.
Tendons are tough cords of connective tissue that connect muscles to bones. Ligaments are elastic bands of tissue that connect bone to bone. Some ligaments of the knee provide stability and protection of the joints, while other ligaments limit forward and backward movement of the tibia (shin bone).
The knee consists of the following:
- Tibia. This is the shin bone or larger bone of the lower leg.
- Femur. This is the thighbone or upper leg bone.
- Patella. This is the kneecap.
- Cartilage. A type of tissue that covers the surface of a bone at a joint. Cartilage helps reduce the friction of movement within a joint.
- Synovial membrane. A tissue that lines the joint and seals it into a joint capsule. The synovial membrane secretes synovial fluid (a clear, sticky fluid) around the joint to lubricate it.
- Ligament. A type of tough, elastic connective tissue that surrounds the joint to give support and limits the joint’s movement.
- Tendon. A type of tough connective tissue that connects muscles to bones and helps to control movement of the joint.
- Meniscus. A curved part of cartilage in the knees and other joints that acts as a shock absorber, increases contact area, and deepens the knee joint.
What is Knee Pain?
It is a pain that is felt in or around the knee and indicates a condition that affects the knee joint itself or the soft tissue around the knee.
What are the Common Causes of Knee Pain?
- Sudden injury
- Overuse injury (sprains or strains)
- Heavy physical activity
- Sitting in a constrained area or on knees for a prolonged period
- An underlying condition, such as arthritis
- Treatment will vary depending on the cause. Knee injury is likely to cause pain, swelling, and stiffness.
What are the Different Types of Knee Replacement Surgery?
Some of the major knee replacement surgeries are:
Total Knee Replacement or TKR is the most common type of knee surgery. In this type, both sides of the knee joint are replaced. The patient experiences less pain and improved mobility. Scar tissues may make it challenging to move and/or bend the knees.
Partial Knee Replacement replaces one part of the knee. It is an alternative to TKR for some patients suffering from osteoarthritis. The surgery can be done when the damage is in a specific compartment of the knee.
Kneecap Replacement replaces the inner part of the kneecap. It is effective for people with severe kneecap arthritis.
Complex Knee Replacement for those who require two or more knee surgeries. It helps ease severe or chronic arthritis.
Who is a Candidate for a Knee Replacement?
Knee surgery is suitable for patients experiencing:
- Severe pain or knee stiffness that does not allow them to do daily activities like walking.
- Moderate but continuous pain that persists even when resting or sleeping.
- Chronic knee swelling or inflammation. The condition does not get better despite taking medication.
- Knee conditions, wherein a noticeable arch or defect lies on the outside/inside the knee.
How long do they Last?
When replacement surgery first started in the early 1970s, the artificial joints were expected to last for about a decade. Now, however, modern implants can last as long as 20 years.