Köhler disease

Overview
Köhler disease (also spelled "Kohler") is a rare bone disorder of the foot found in children between six and nine years of age. It was first described in 1908 by Alban Köhler (1874-1947), a German radiologist.

It is caused when the navicular bone temporarily loses its blood supply. As a result, tissue in the bone dies and the bone collapses. When treated, it causes no long term problems. As the navicular bone gets back to normal, symptoms typically abate.

Symptoms
Sufferers experience pain and swelling in the middle part of the foot and usually limp as a result. The disease typically affects boys, but it can also affect girls. Five is the age of boys most often affected and patients often complain of pain over the apex.

X-ray of both feet is used to diagnose disease. The affected foot has dense flattened navicular bone.

Causes
Although no definitive cause has been found yet, the disease may be due to strain on a weak navicular bone.

Treatment
The patient is often fit with a cast that stops below the knee. Moderate exercise is often beneficial.