[Unstable fractures of the distal radius: a new classification]

We have carried out a retrospective study of 100 fractures of the distal radius which were classified according to 3 principal factors, namely the amount of displacement (D), the involvement of the epiphysis (E), and the degree of metaphyseal comminution (M). Each of these 3 groups was further divided into 4 levels of increasing instability. The fractures were assessed 3 months after injury. Most occurred in old patients with low grades in the DEM scale, often in association with osteoporosis and following a simple fall. Metaphyseal comminution and the degree of displacement did not correlate with the degree of osteoporosis. The highest grades of epiphyseal lesions occurred in young patients, and intact epiphyses were seen in the more osteoporotic population. The Kapandji technique, using 3 Kirschner wires, was used in 58 cases, mostly with low grades of DEM, and gave satisfactory results, but in 14% anterior carpal translation was noted. This may lead to anterior instability. External fixation was employed in 32 patients with higher grade fractures. A good anatomical result was usually obtained but the wrists were more stiff. In 7 of these patients fixation of articular fragments by wires was also needed. Reduction and immobilisation in a cast was undertaken in 7 cases with variable results. Double cortical pinning was used in 3 patients and was useful in the highest grades of displacement. We outline a scheme for treatment based on our classification.