抄録
We review three cases of thoracic outlet syndrome caused by anomalous pseudarthrosis of the first rib to the second rib. Each case had progressive symptoms of numbness and pain in the upper limb. Roos'operation was performed in each case. In their thoracic outlet portion, abnormal structures of scalenus minus muscle and fibrous bands were found and the histology of pseudartirosis was degenerative hyaline cartilage. At follow-up all, the patients were free of symptoms.
