Psoriatic arthritis can be called a type of psoriasis. It is actually psoriasis of the joints. During it, the joints are inflamed and therefore the patient feels pain and swelling in the affected joints. In some cases, the joints are damaged as well. However, such damage is very slow. The causes of psoriatic arthritis are not known however, it is thought to be associated with genetic mutations.

As the causes of psoriatic arthritis and psoriasis are, some they both generally occur together. Therefore, the patient in addition to the symptoms of arthritis also faces the symptoms of psoriasis of the skin.

Generally, in psoriatic arthritis psoriatic patches are developed on the skin above the affected joint.  The red and scaly patches are developed on the skin. The patches are painful and the skin in such patches becomes sensitive. It can be easily damaged. If not treated the patches go on developing and they may reach these other parts of the body as well. In addition, black spots in the form of pigmentation appear around the patches.

Nevertheless, as the causes of psoriatic arthritis and psoriasis are same, and they occur in association with each other the psoriasis patches can also develop on the skin form any region of the body. The most prominent sites of development of such patches are the skin under knees and elbow.

Apart from these symptoms, the swelling in the joints also affects the skin above it. This happens in the advanced stages when the inflammation increases and therefore the joints start to swell up. The swelling increases so much that the entire part in which the joint is present swells up. In such a condition, the skin appears red. Moreover, the skin becomes sensitive and therefore it starts paining.

In addition to the skin, the nails are the prominent parts, which are affected by psoriatic arthritis. Similar to the skin patches develop on them as well. These patches are associated with pits as well. In the advanced stages, psoriatic arthritis may result in the loss of the entire nail as well.

Even though the causes of psoriatic arthritis are not known, they have unwanted effects on the skin as well as the joints. Therefore, it should be treated as early as possible. Effective treatments are available for curing psoriatic arthritis. The effects on the skin are the indications of psoriatic arthritis and therefore useful in diagnosing it.