What Are The 4 Stages Of Osteoarthritis & At What Age Does It Begin?

Osteoarthritis is a degenerative condition occurring due to increased break down of cartilage present in the joint as compared to its production which also decreases with age. It may or may not be categorized in inflammatory arthritis nowadays due to increasing evidence in the favor of chronic inflammation but it was initially categorized as non-inflammatory arthritis.

What Are The 4 Stages Of Osteoarthritis?

Osteoarthritis has been divided into four stages based on etiopathogenesis as well as clinical features. Initially, etiopathogenesis had only 3 stages but now the 4th stage has also been added. Firstly, the pathogenic stages have been described:

Stage 1: – Due to the ongoing stress on the joint involved, there is a starting of the proteolytic breakdown of the cartilage matrix which is usually localized at a particular site but can be generalized also.

Stage 2: – After the breakdown of cartilage has progressed, there is the erosion of the surface of the cartilage and the breakdown products such as proteoglycans and collagen fragments start making in the joint space.

Stage 3: – These breakdown products of the synovial cartilage start a process of chronic inflammation in the joint space which will increase the further breakdown rate. The damage in the joint space worsens and the compensatory mechanism starts to fall apart.

Stage 4: – To control the damage occurring to the cartilage surface and reduce the inflammatory process, there is starting of the ossification process at the site leading to bony spur formation. The body tries to help the condition by replacing the original tissue with a hard substitute but in the prices causes more harm than good.⁽¹⁾

Clinical stages have also been classified into four categories and nearly corresponds to the etiopathogenic staging.

Stage 1: – (MINOR) Minor wear and tear are present at the surface of joint with nearly no radiological evidence for it. The person also feels negligible symptoms, although there may be a complaint of pain sometimes on prolonged walking.

Stage 2: – (MILD) The amount of wear and tear increases along with bony spur formation as seen in the radiological investigations. Although, the joint space is nearly normal. The patient has more frequent complaints of pain in the knee joint but it is not as bad as unbearable.

Stage 3: – (MODERATE) There is obvious bony spur formation with reduced joint space and increased roughness of the cartilage surface. It can also be seen and confirmed upon the X-ray. There is a lot of pain with increased frequency and also sometimes there is crepitus generation when a person changes its posture after a long time. The movement of the joint is hampered but not completely stopped.

Stage 4: – (SEVERE) There is reduced or almost nil joint space with the presence of Bony fusion of the joint at various places. It can be seen upon gross clinical examination as well as on the basic radiological investigation like an x-ray. The movement of the joint is severely hampered and pain also becomes unbearable. In its later stage, pain may disappear because of complete fusion of the joint and movement becomes impossible at that joint.

At What Age Does Osteoarthritis Begin?

Osteoarthritis is usually is seen in the elderly age group above the age of 50 years. It is very rarely seen below 50 years because the capacity of the body to compensate for damage occurring at the joint is not reached at its maximum. According to a radiological survey, nearly 50 % of the patients above the age of 65 years has radiological evidence of osteoarthritis.

Conclusion

Staging of the osteoarthritis is based upon the clinical features, radiological features and the pathological features observed at the tissue level. It is the disease of the elderly age group with predominant cases occurring after the age of 65 years.

References:

Also Read:

What Are The 4 Stages Of Osteoarthritis & At What Age Does It Begin?