Optimizing the Orientation of a Suture Button to Stabilize the Distal Radioulnar Joint in a Sawbones Model.

PURPOSE: When left untreated, distal radioulnar joint (DRUJ) instability leads to prolonged wrist pain and weakness during pronosupination. Current treatment options are technically demanding and result in mixed outcomes. This study used a synthetic bone model to evaluate the potential of using a suture button to stabilize the DRUJ and find its optimal configuration.

METHODS

A suture button was placed between the radius and ulna of a synthetic bone model with DRUJ instability. The suture button was placed straight across or in an oblique orientation while the forearm was in 60° of pronation, neutral, or 60° of supination for 6 configurations. The range of motion, dislocation events, dorsal translation, volar translation, and gaps between the radius and ulna were measured and compared among these 6 configurations.

RESULTS

Full range of motion (ROM) was achieved in all configurations except for suture buttons placed while the forearm was in 60 ° pronation. Obliquely placed suture buttons led to more dislocations than straight across suture buttons. The 2 configurations that offered full ROM with the greatest stability were straight across 60° supination and straight across neutral configuration, with the supinated configuration slightly improving stability.

CONCLUSIONS

In this model, suture buttons restored DRUJ stability while maintaining full ROM, indicating that suture buttons have the potential to be used as a treatment option for stabilization of DRUJ. The optimal configuration of a suture button is likely in the straight across 60° supinated configuration, as it provides the greatest stability without sacrificing ROM compared with the other suture button configurations.

CLINICAL RELEVANCE: Additional treatment options for the stabilization of DRUJ are needed. Suture buttons may be of use.