Fri-09-09-2011, 19:54 PM
Psoriatic Arthritis
Approximately 10-20% of those with psoriasis may develop some form of arthritis.
What is psoriatic arthritis ?
• When joints are inflamed they become tender, swollen and painful on movement.
• Joints are typically stiff after resting, early morning or resting in the evening.
• Tissues such as ligaments, tendons around the joints may be involved.
• Inflammation of tendon or muscle (such as tennis elbow (Lateral Epicondylitis) and pain around the heel) is also a feature in those with psoriatic arthropathy.
• In approximately 80% of cases the arthritis develops after the appearance of psoriasis.
• In 20% of cases the joint inflammation comes first.
Joints normally function to allow movement to occur between bone ends, which are important for the body to move. Bone ends are covered with cartilage around which is a capsule lined by a membrane called synovium.
This membrane normally makes the fluid that lubricates the joint space allowing movement. In arthritis the synovial membrane becomes inflamed - and releases substances that cause inflammation.
The inflamed synovium releases more fluid than normal and so the joint becomes tender and swollen. Persistent inflammation may lead to damage to the cartilage and erosion of the underlying bone.
Synovial membrane also lines and lubricates tendons and so they become inflamed too.
There are several features that distinguish PA from other forms of arthritis:
• Particular patterns of joints that may be involved.
• One pattern of inflammation is usually in the end joints of fingers often corresponding with the fingers that have psoriatic nail involvement, which is more common in men than women.
• Another pattern is involvement of the joints of the spine and sacroiliac joints which is called spondylitis similar to ankylosing spondylitis.
• Neck pain and stiffness.
• An entire toe or finger can become swollen or inflamed which is termed dactylitis.
• There is a tendency for joints to stiffen up and sometimes to fuse together.
• Importantly the absence of rheumatoid factor in the blood helps distinguish psoriatic arthritis from rheumatoid arthritis.
• Distinguishing features are not always present and the individual may have swelling of a few or many joints that is similar to other types of arthritis making diagnosis difficult.
In 80% of individuals with arthritis, psoriatic nail changes are found, which is more common than with psoriasis alone.
Nail changes include pitting, discolouration of the nail due to abnormalities in the growth of tissue in the nailbed.
The risk of developing arthritis is greater in individuals with severe psoriasis, yet occasionally severe arthritis may occur with minimal skin disease.
Approximately 10-20% of those with psoriasis may develop some form of arthritis.
What is psoriatic arthritis ?
• When joints are inflamed they become tender, swollen and painful on movement.
• Joints are typically stiff after resting, early morning or resting in the evening.
• Tissues such as ligaments, tendons around the joints may be involved.
• Inflammation of tendon or muscle (such as tennis elbow (Lateral Epicondylitis) and pain around the heel) is also a feature in those with psoriatic arthropathy.
• In approximately 80% of cases the arthritis develops after the appearance of psoriasis.
• In 20% of cases the joint inflammation comes first.
Joints normally function to allow movement to occur between bone ends, which are important for the body to move. Bone ends are covered with cartilage around which is a capsule lined by a membrane called synovium.
This membrane normally makes the fluid that lubricates the joint space allowing movement. In arthritis the synovial membrane becomes inflamed - and releases substances that cause inflammation.
The inflamed synovium releases more fluid than normal and so the joint becomes tender and swollen. Persistent inflammation may lead to damage to the cartilage and erosion of the underlying bone.
Synovial membrane also lines and lubricates tendons and so they become inflamed too.
There are several features that distinguish PA from other forms of arthritis:
• Particular patterns of joints that may be involved.
• One pattern of inflammation is usually in the end joints of fingers often corresponding with the fingers that have psoriatic nail involvement, which is more common in men than women.
• Another pattern is involvement of the joints of the spine and sacroiliac joints which is called spondylitis similar to ankylosing spondylitis.
• Neck pain and stiffness.
• An entire toe or finger can become swollen or inflamed which is termed dactylitis.
• There is a tendency for joints to stiffen up and sometimes to fuse together.
• Importantly the absence of rheumatoid factor in the blood helps distinguish psoriatic arthritis from rheumatoid arthritis.
• Distinguishing features are not always present and the individual may have swelling of a few or many joints that is similar to other types of arthritis making diagnosis difficult.
In 80% of individuals with arthritis, psoriatic nail changes are found, which is more common than with psoriasis alone.
Nail changes include pitting, discolouration of the nail due to abnormalities in the growth of tissue in the nailbed.
The risk of developing arthritis is greater in individuals with severe psoriasis, yet occasionally severe arthritis may occur with minimal skin disease.