Abstract
This study reports the results of open reduction and internal fixation of 26 unstable, intra-articular, dorsally displaced fractures of the distal radius using a bio absorbable dorsal distal radius (Reunite) plate and calcium phosphate (Biobon) bone substitute. The bio absorbable plate has the advantages of being low profile, easily contourable due to temporary malleability and is angularly stable. It retains its strength for 6 to 8 weeks and undergoes complete mass loss within one year, thereby allowing gradual load transfer to the healing bone. In the majority of cases, this plate produces functional results comparable with metal plates.
The Gartland and Werley score was excellent or good in 21 patients. The most important advantage over metal plates is in eliminating the need to remove the plate and hence the need for a second operation if implant related extensor tenosynovitis occurs. Inflammatory tissue reaction to the degradation products of the plate is a potential concern, although the co-polymer ratio used in this plate appears to have reduced the severity of this reaction, which was seen in two patients in this series. The reduction was lost in five patients with severe dorsal comminution. For such fractures, the plate did not retain its strength for long enough to allow adequate healing for satisfactory load transfer.
Following this experience, we do not recommend this plating system for fractures with a metaphyseal gap of greater than 7 mm following reduction. For fractures that cannot be treated by closed means but where the metaphyseal gap following reduction is less than 7 mm, this plate provides all the theoretical advantages. Further developments allowing the plate to retain its strength for longer while maintaining the low incidence of inflammatory reactions will make it more universally applicable for the treatment of a greater spectrum of unstable distal radius fractures.