[Angioma like dysplasia of synovial membrane with phlebectasia causing palindromic joint swelling in childhood (author's transl)].

In a five year old boy who had intermittent knee joint swelling, angioma like venous dysplasia of synovial membrane was diagnosed by arthroscopic examination. The arthroscopic diagnosis was the indication for arthrotomy. The suprapatella pouch of the knee joint contained a blue grape like tumor. Angiomalike venous dysplasia of the synovialmembrane can histologically be separated from other angiomas of the inner joint capsule and angiomalike alterations in other joint diseases. Arthroscopy should be performed if within half a year monarticular intermittent joint swelling in childhood can not be diagnosed.