Accessory ossifications in the ulno-carpal wrist region.

Accessory ossifications in the ulno-carpal transition such as ossa styloidea or triangularia represent a rare finding, especially among younger individuals. The present results of radiological and morphological investigations show that up to 50% of the ossa are located palmar to the styloid process. Most of them have a sharply bordered contour and are less than 10 mm in length. An aetiological classification of accessory ossifications in the distal epiphyseal region is only possible when an obvious case history is available. Accessory skeletal elements are present among elderly individuals as a result of sclerotic alterations of the ulno-carpal joint elements. Among younger individuals, however, they point to a pathological aetiology and can therefore assume clinical and diagnostic relevance in cases involving inflammatory rheumatic and traumatic alterations accompanied by vague discomfort in the proximal wrist region.