A Biomechanical Study And Clinical Application Of Single-bundle Suture Button Reconstruction In Distal Radioulnar Joint Dislocation

Objective:To explore the difference of rotation function of single-bundle suture button instead of Kirschner wire in the treatment of distal radioulnar joint(DRUJ)dislocation by biomechanical experiment and clinical application.Methods:Biomechanical experiment: six healthy adult forearm specimens were randomly selected,and four groups of torque biomechanical test models were successively constructed,including normal DRUJ group,DRUJ dislocation group,Kirschner wire reconstruction group,and single-bundle suture button reconstruction group.Six adult forearm specimens under four conditions were tested with NWS1000 torsion machine.The limited conditions were as follows: torsion speed 5°/min,maximum rotation angle90°and maximum torque 1.0N·m.Clinical application: two patients with DRUJ dislocation in the same period,one was fixed with Kirschner wire,another was fixed with singlebundle suture button.Results:Biomechanical test results showed that in the range of 0 to 1.0N·m torque,the pronation or supination angle of DRUJ dislocation group >normal DRUJ group > single-bundle suture button reconstruction group >Kirschner wire reconstruction group at the same torque.When the torque was 0.5N·m,there was no significant difference in the supination angle between the single-bundle suture button reconstruction group and the normal DRUJ group(t = 2.011,P = 0.1 > 0.05).In addition,there were significant differences(P < 0.05)in the rotation angles of forearm under0.5N·m and 1.0N·m torque conditions.The follow-up results showed that there were no postoperative complications in two patients,and two patients achieved satisfactory results,but the pronation angle of the affected side forearm less than the healthy side after Kirschner wire reconstruction.Conclusion:Biomechanical test results showed that the restriction of DRUJ rotation could be restored by the two methods,and the restriction was stronger than that of the normal original structure.The rotational restriction of DRUJ in the single-bundle suture button reconstruction group was closer to that of the normal DRUJ.The results of clinical application show that two methods can achieve good results,however,the wastage of forearm rotation function is less by single-bundle suture button reconstruction.