Dynamic external traction combined with internal fixation for treatment of comminuted intra-articular fractures of the base of the thumb proximal phalanx

Abstract

Objective To document the efficacy of our modified dynamic external traction system that is applied concomitantly with internal fixation for comminuted fractures at the base of thumb proximal phalanx. Methods From March 2009 to July 2014, 7 cases of comminuted fractures at the base of thumb proximal phalanx with metacarpophalangeal(MP) joint involvement (AO type C fractures) were treated with open or close reduction and internal fixation. Meanwhile a dynamic external traction system was applied. Postoperative exercise started early.Range of motion of the MP joint, pinch strength and postoperative complications were evaluated. Results Postoperative follow-up period ranged from 13 to 32 months, with an average of 18 months. The mean plaster splint immobilization time was 7.7 days (range, 3 to 14 days). The external fixator was removed at 4.3 weeks on average (range, 4 to 6 weeks). The internal fixation hardware removal time was 7.2 weeks postoperatively on average (range, 6 to 9 weeks). All the patients were able to return to their original jobs. The average active range of motion for the MP joint of the thumb was 8.6° (range, 5° to 10°) extension and 42.4° (range, 35° to 50°) flexion. Mean pinch strength was 89% of that of the contralateral side. According to the upper extremity functional evaluation criteria issued by the Hand Surgery Society of the Chinese Medical Association, the results were rated as excellent in 5 cases and good in 2 cases. Conclusion Dynamic external traction system combined with internal fixation can provide reliable fracture fixation and allow early mobilization of the MP joint. The variable traction force can effectively maintain joint stability during movement and reduce adhesion and contracture of the joint. Key words: Thumb; Finger phalanges; Intra-articular fractures; Dynamic traction