The unstable distal radius fractures result in various residual disability, and the instability can be recognized by the presence of much comminution, severe dorsal angulation or extensive intraarticular involvement. It is disfficult to reduce the fracture fragments and immobilize it with classical closed rduction and cast immobilization. So many authors have tried to reduce it with invasive methods and apply supplementary fixztion.

Clinical and radiological analysis was made in 29 patients of unstable distal radius fracture who treated in Kyung Hee University Hospital from Jan. 1983 to Dec, 1987.

The results were as following;

1. The unstable distal radius fractures were 24% of the distal radius fractures which were treated with admission.

2. In prevalence, male was mostly young men, but female was mostly old women.

3. The most frequent Frykman type was VIII(48.3%), but it could not represent the degree of comminution and displacement sufficiently.

4. Most of the patients treated by conservative method showed poor results. But operative treatment made it possible to align the fragment anatomically, restore the congruity of articular surface and prevent the collapse of reduction, so satisfactory results were obtained.

5. The unstable factures with large cortical defect or severe comminution required internal fixation for anatomical reduction and at the same time required additional external fixation to prevent the collapse and shortening of the distal radius.