Arthritis of the Knee

 

Osteoarthritis of the knee is the most common cause of arthritis of the knee. The patient will complain of pain, swelling, stiffness, and decreased range of motion of the knee. In arthritis, the cartilage of the knee gets worn off. The meniscus which absorbs the shock, becomes degenerated and tears. Which time, there will be more and more degeneration with wear and tear on the knee joint. The joint space becomes narrower and narrower. When the cushion of the cartilage is completely lost, the bone will rub against bone, causing severe symptoms to the patient with severe pain, inability to walk, a lot of swelling with the knee, and “giving way” (knee will be unstable). The x-ray will show arthritis. When you ask the patient to stand or walk, the alignment of the lower extremity is lost, and the patient may have varus or valgus malalignment. With varus deformity, the bowing end of the leg occurs more with medial osteoarthritis (common), and the patient will compensate for the arthritis and pain in the knee by limping. The patient is trying to reduce the weight being placed on the knee. The stance phase on the affected knee will be shortened. The patient cannot take the pain any longer, so they are quick to get the foot off the ground due to the painful knee. Arthritis can be mild, moderate, or severe. To understand the arthritis, you need to know the anatomy of the knee. Synovial fluid lubricates the knee joint. As you can see here at the end of the femur and the tibia, there is hyaline articular cartilage which is smooth and allows for smooth movement of the joint. There are no holes, no fissures or cracks in the normal hyaline cartilage. For mild osteoarthritis of the knee, the patient will have some discomfort, and the x-rays can appear normal. The fabric of the articular cartilage breaks down. The process of wear and tear, being overweight, and enzymes will affect the cartilage, and the cartilage will break down (it is mild or minimal) which can be controlled by nonsteroidal anti-inflammatory medication, weight loss and therapy. For moderate osteoarthritis, there will be narrowing of the joint space on x-ray due to degeneration of the cartilage. There will be cysts in the subchondral space located underneath the cartilage, and there may be some osteophytes or bony spurs. The joint will no longer be smooth (joint surface is roughened with cracks and fissures). The patient’s pain will be worse with more swelling. This is the time when the physician has a lot of options, but none of them are optimal. You may try nonsteroidal anti-inflammatory medication or try weight loss and exercises, steroid injection (viscosupplementation or hyaluronic acid injections). Recently, long acting steroid injections is used. Other doctors may try platelets and stem cells. None of the options are proven to be successful. The only protocol that is proven to be successful is weight loss, exercises, and nonsteroidal anti-inflammatory medication. For severe osteoarthritis, the condition of the knee is bad. The joint space is severly narrowed with total destruction of the cartilage. The knee is swollen and painful with more osteophytes, and the bone is rubbing against the bone, and no cartilage is left. There is no cushion and nothing to absorb the shock of the weight, so the condition becomes very painful. The patient’s knee is like a car that is running on its rim. Because the patient is walking on their own bone, there will be decreased activity, and the patient will have an inferior quality of life. Surgery is the best option for the patient and surgery is usually done by a total knee replacement. Total knee replacement is like a house that has a roof that leaked, you want to change the roof of the house. Total knee replacement is the same thing. You need to fix the damaged roof of the house and fix the destruction to the knee.