What is Psoriatic Arthritis?
Psoriatic Arthritis is a chronic condition that causes skin rashes (psoriasis) and joint inflammation. It can occur at any age, particularly between the ages of 30 to 55 years. It affects both men and women equally.
Not everyone with psoriasis will develop arthritis. Psoriatic arthritis affects approximately 10% to 30% of patients suffering from psoriasis. Therefore it is essential that patients with psoriasis are informed about this when they are first diagnosed, so that they can seek early treatment for their joints if they develop arthritis at a later stage.
Joint involvement in psoriatic arthritis show diverse presentation, from an isolated painful joint swelling to extensive destruction of multiple joints. The arthirits often involve the knees, ankles and joints in the feet. Usually, a few joints are inflamed at a time. Patienst with inflamed joints experience pain, swelling, redness and warmth over the joints. Another common symptom is joint stiffness which is typically worse early in the morning.
Sometimes, psoriatic arthritis can cause inflammation of the tendons of fingers and toes with redness and swelling. This gives rise to a sausage-like appearance and is known as “dactylitis”. Inflammation can occur over the tendon behnd the heel. This is known as Achilles tendonitis and it can lead to pain while working and climbing stairs.
Psoriatic Arthritis at toes
Patients with psoriatic arthritis can also have associated nail changes. Around 60% to 80% have pitting of the nailes (appearance of pinpoint pits on the surface of the nails), ridges and onycholysis (painless separation of the nail from its bed).
Apart from the joints of the arms and legs, those along the spine and the sacrum (lower back) can become inflamed too, resulting in pain and stiffness in the neck and lower back. This is, however, uncommon.
What causes psoriatic arthritis?
The cause is still unclear although heredity is believed to play a major role. Children of parents with psoriasis are 3X more likely to have psoriatic arthritis. Other possible causes of psoriatic arthritis are exposure to infection, trauma, changes in the environment or psychological stress.
Approximately 67% of patients develop psoriasis before the onset of arthritis. The other 16% experience the two conditions within 12 months of each other while arthritis precedes psoriasis in the remaining 17%.
Similar to most other forms of arthritis, psoriatic arthritis has periods of flare-up and remission. Patients need to learn how to manage their condition to minimise flare-up and prolong remission periods so that they can have a better quality of life.