Everything You Need To Know About Knee Osteoarthritis

knee osteoarthritis

Osteoarthritis (OA), occurs because of tear as well as wear and gradual or progressive loss of one’s articular cartilage. It is most commonly observed in elderly people and there are 2 types of it which are:

  • Secondary
  • Primary

Primary osteoarthritis is articular degeneration without an apparent underlying cause. As for secondary osteoarthritis, it is a consequence of either the atypical articular cartilage-like rheumatoid arthritis (RA) or the atypical concentration of the force across one’s joint as with the post-traumatic causes.

This disease keeps progressing, eventually leading to disability. The intensity of clinical symptoms typically varies depending on an individual, but symptoms usually become more frequent, more debilitating as well as more severe over time. The rate of progression can vary for each individual as well.

Common clinical symptoms are:

  • Knee pain which is slow in onset and gets worse with activity
  • Knee stiffness as well as swelling
  • Pain after prolonged resting or sitting

The treatment for this disease typically starts with conservative methods and then progresses to the surgical treatment options in case conservative treatment is not successful. Even though medications help in slowing the disease’s progression as well as other inflammatory conditions, there are currently no effective disease-modifying agents that can treat knee osteoarthritis.

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OA remains the most common disease of joints worldwide and the knee is the most commonly affected joint in a body. This disease mainly affects people who are over the age of twenty-five.

However, not every person with the radiographic findings of knee OA is symptomatic: In one study it was found that only fifteen percent of patients with the radiographic findings of knee osteoarthritis were symptomatic.

Five Stages Of OA

There are five stages of osteoarthritis (OA). Stage 0 gets assigned to a healthy, normal knee. The highest stage 4 gets assigned to a severe OA. This stage has already reached the advanced phase and so it is more likely that it will cause significant pain as well as disrupt joint movement.

Stage 0

Stage 0 is referred to as “normal” knee health as one’s knee joint does not show any signs of OA. The joint normally function without any pain or impairment as well.

Stage 1

A person who has a stage 1 OA starts showing some signs of bone spurs. Bone spurs are bony growths that often develop where the bones meet one another in the joint.

An individual with stage 1 OA does not usually experience any discomfort or pain as a result of some small wear on components of a joint.

Stage 2

Stage 2 OA of one’s knee is considered a “mild” phase of the disease. X-rays of the knee joints taken during this stage can reveal much severe bone spur growth. However, the cartilage is typically still at its healthy size, meaning a space between one’s bones is normal. Bones are not scraping or rubbing each other, either.

At this stage, synovial fluid is usually still present at the sufficient levels for a normal joint motion.

However, this is exactly the phase where people start experiencing symptoms, such as pain after the long day of running or walking, greater stiffness in one’s joint when it is not used for a couple of hours. Other times, people may experience tenderness while bending or kneeling.

Stage 3

Stage 3 OA is referred to as a “moderate” OA. During this phase, the cartilage between a person’s bones reveals some obvious damage. A space between bones starts to narrow as well. Individuals with stage 3 of OA are more likely to start experiencing frequent pain when running, walking, kneeling, or bending.

They can also start experiencing joint stiffness when they wake up early in the morning or after they have been sitting for prolonged periods of time. Joint swelling can be present after the prolonged periods of motion, too.

Stage 4

Stage 4 of this disease is considered severe. Individuals in stage 4 of osteoarthritis start experiencing tremendous discomfort and pain while walking or moving the joint.

That happens because joint space between the bones is extremely reduced and cartilage is almost gone which leaves the joint stiff as well as possibly immobile. Also, the synovial fluid decreases dramatically, and it can no longer help in reducing friction among moving parts of the joint.