The Arthritis that affects Nails, Tendons (Entheses) & Skin

By Dr Irwin Lim, Rheumatologist

The non-doctors among you will still clearly see the destruction evident in those hands.

This lady presented late with the damage already done. For decades, she had been treated as having Osteoarthritis of the hands. She does have this, but she also reported intermittent painful softer tissue swelling with a lot of stiffness.

In her case, she has both osteoarthritis of the hands and psoriatic arthritis.

The clue was her skin.

She has psoriasis affecting her scalp and her elbows. This has been mild and has been treated with steroid creams and tar-based shampoos over the years. Psoriasis is a very common skin condition with the skin becoming red and irritated, and typically scaly.

Chances are that someone in your family or someone you know has psoriasis.

The diagnosis of psoriasis is usually pretty straightforward. It needs a doctor to look at the skin for the typical features.

In up to 30% of patients with psoriasis, there is an associated arthritis. This makes Psoriatic arthritis very common and like many rheumatic disease, the diagnosis seems to often be missed.

Some patients with psoriasis have changes in their nails, such as increased pits seen in the nail, increased ridges or even lifting of the nail. These patients with nail involvement are more likely to also have their joints affected.

Psoriatic arthritis can present in many ways:

• Big joint disease, such as knee swelling or pain
• Small joint disease, such as swelling in the joints in the hands or feet
• Spine disease with Inflammatory Spinal Pain
• Swelling of the toes or fingers, to the point the involved digit looks like a sausage (called dactylitis)
• It can affect all of the above, in any combination.
• It can affect many joints simultaneously, or only 1 joint.
• The arthritis can occur periodically or can be progressive, either slowly or rapidly.
• The arthritis can be relatively mild or can be terrible destructive.

In addition, tendon problems and more specifically, inflammation where tendons insert (known as Enthesopathy / Enthesitis) are very common. Think of tennis elbow, quadriceps tendinopathy, plantar fasciitis or achilles problems.

The ability of psoriatic arthritis to present in such a diverse way may be one reason it's not diagnosed more often. Perhaps, the symptoms are explained in some other way. Wear and tear, osteoarthritis, sporting injury are all easy to blame.

We really do need to improve awareness of this disease.

Most patients with psoriasis have never been told about the possible non-skin manifestations.

If you or someone you know has psoriasis, and is complaining of joint or tendon problems, at least consider psoriatic arthritis as a possible cause.