What's a Sausage Finger?

Many types of arthritis can cause a sausage digit. The technical term for this is "dactylitis."

This is not the kind of sausage you would have with your eggs and pancakes.

Sausage digits are typically seen in conditions such as psoriatic arthritis (the arthritis that accompanies psoriasis), Reiter's disease, inflammatory bowel disease, and occasionally ankylosing spondylitis. Of these, psoriatic arthritis is probably the most common culprit. Dactylitis means inflammation of an entire finger or whole toe.

It is caused by inflammation involving the synovium (lining of the joint) as well as the lining of the tendon sheath. Tendons are tough fibrous bands that connect muscles to bones. Most tendons glide through a lubricated sheath lined with synovium. When the synovium in the joint and the tendon sheath becomes inflamed, the entire finger or toe will swell.

The tendons that are most often affected are the tendons that allow a person to bend or flex their fingers or toes.

If a patient has dactylitis, their prognosis is poorer in that the joints are more likely to sustain damage. The presence of dactylitis indicates a greater chance for disease progression.

Early on, dactylitis may be extremely painful. However, over time, as destructive changes occur, the inflamed tissue is replaced with bony deformity and the dactylitis no longer causes severe pain. However, the swelling persists.

The presence of dactylitis should prompt a diagnostic workup. Diagnosis can be substantiated by magnetic resonance imaging (MRI). Recently, diagnostic ultrasound has also been found to be helpful.

The treatment of dactylitis depends on the number of digits affected. If only a few fingers or toes are involved, ultrasound-guided steroid injection can be helpful for the acute situation.

However, the more important part of treatment is to initiate disease modifying therapy as soon as possible.
Generally, the dactylitis is often accompanied by enthesitis. This is inflammation at tendon insertions such as the Achilles tendon, patellar tendon (the tendon that connects the kneecap to the tibia-lower leg bone, and the iliac crest.

Every disease that causes dactylitis is a systemic disease. This is because the underlying pathology involves an abnormal immune response. So other organ systems can become affected. An example is the eye where uveitis- inflammation of the middle layer of the eye- can occur. Uveitis is a potentially serious complication that can lead to blindness.

Institution of drugs like methotrexate or sulfasalazine (Azulfidine) may be useful.

However, most patients will require the use of biologic therapies.