[Unexplained pain conditions of the upper extremity].

Diagnosis can be very difficult in the case of painful conditions of the upper extremity, since this is a region where the site of the changes and pathologic conditions precipitating or causing the pain is not always identical with the area where the pain is felt. This is particularly so in the case of pain resulting from vascular disease and irritation of peripheral nerves and in the thoracic outlet and inlet syndrome. Recent observations and studies suggest that this is extremely important for the etiology and pathogenesis of epicondylar periostitis and tendovaginitis, carpal tunnel syndrome, and some trophic conditions affecting the hand. Stenosis of the subclavian vein can be responsible for post-traumatic and postoperative edema of the hand and for similar changes whose "cause is unclear", and also for certain difficulties with wound healing. Preliminary experience suggests that Sudeck's dystrophy may be the most severe form of the thoracic outlet and inlet syndrome. Accordingly, transaxillary decompression of the neurovascular cord with upper thoracic sympathectomy can be recommended as a last resort for refractory Sudeck's dystrophy. The problem of epicondylitis of the lateral humerus is discussed in some detail, as is the pathogenesis of pain resulting from neuroma.