Comminution of the dorsal metaphysis and its effects on the radiographic outcomes of distal radius fractures.

Comminution of the dorsal metaphysis is a relatively common feature of distal radius fractures. However, its effects on the radiographic outcomes of these fractures are not entirely understood. One hundred and twenty-four conservatively managed distal radius fractures were analysed retrospectively to assess the effect of dorsal metaphyseal comminution on fracture stability, especially with respect to initial displacement (minimally displaced versus displaced) and age group. Seventy-seven fractures (62%) had radiographic evidence of dorsal comminution. The secondary displacement rate of these fractures was 75%, compared to 45% in non-comminuted counterparts (P<0.001). In minimally displaced fractures, the secondary displacement rate was higher in those with dorsal comminution as compared to those without (57% vs. 31%, P=0.086). Dorsal metaphyseal comminution was found in 75% of fractures in patients 65+years old (P=0.05). Among those with dorsal comminution, the secondary displacement rates were similar for both men and women (63% vs. 79%; P=0.20). In conclusion, distal radius fractures with dorsal metaphyseal comminution had significantly higher rates of secondary displacement compared to non-comminuted counterparts, and there exists a correlation with this displacement and increasing patient age but not gender.