What is Knee Arthritis?
Arthritis is a painful disease of the joints that affects more than 50 million adults worldwide. The most common type of arthritis is that of the knee, which presents itself in various forms.
Types of Knee Arthritis
The specific type of knee arthritis is defined based on the areas affected by arthritis, prior injury of the knee, origin of the arthritis, and the age of the patient. These factors make up five separate types of knee arthritis including osteoarthritis, post-traumatic arthritis, rheumatoid arthritis, juvenile idiopathic arthritis, and reactive arthritis.
This first form of arthritis is the most common. Osteoarthritis can be found in any area of the body, but is most often located in the knees, hips, low back, or neck.
- Causes: Osteoarthritis is degenerative, meaning that it occurs from the natural wear and tear of the joint’s cartilage over time. As a person ages, the cartilage between their joints begins to wear down. After much of this cartilage is gone, the joint begins to rub one bone directly against another, resulting in very intense pain.
Post-Traumatic arthritis is a more specific form of osteoarthritis.
- Causes: This type of arthritis is caused by the same degeneration of cartilage. However, this wear and tear is worsened by a particular injury to the knee such as a tear of the meniscus or the anterior cruciate ligament (ACL).
Rheumatoid arthritis differs from osteoarthritis because rather than being solely located in the knee joint, rheumatoid arthritis can also be present throughout the rest of the body. You will find that if rheumatoid arthritis exists in a joint on one side of the body, it will also exist in the same joint on the other side of the body, which means that it will often be present in both knees.
- Causes: As of now, there is no real explanation for the cause of rheumatoid arthritis. Many experts point to the proven relationship between autoimmune diseases and inflammation of the joints. It is unclear what exactly propels the immune system to go awry, but evidence suggests that genes, hormones, and environmental factors may play a crucial role.
Reactive arthritis is an inflammatory arthritis that may affect joints as well as other areas of the body like the eyes, skin, and urinary tract.
- Causes: This type of arthritis is very unique as it is caused by bacteria that has managed to enter the bloodstream by way of the urogenital tract or gastrointestinal tract. Due to its origin, reactive arthritis is often associated with both conjunctivitis and urethritis.
Patients usually report the following symptoms of knee arthritis:
- Soreness/stiffness of the knee
- Limited range of mobility
- Accumulation of fluid around the joint
- Clicking or cracking during movement of the knee
- A grating or scraping sensation
- Pain that worsens during or after daily activity
- Fever and rash (specific to juvenile idiopathic arthritis)
- Treatment for severe osteoarthritis