Elastic fixation with Tightrope system for inferior tibiofibular syndesmosis diastasis: a cadaveric study / 中华创伤骨科杂志

ABSTRACT

Objective:To study the performance of the elastic fixation with our self-designed Tightrope system for inferior tibiofibular syndesmosis (ITFS) diastasis.Methods:In this self-control study, 6 specimens of normal cadaveric ankle were used as a normal ITFS group while the models of the ITFS diastasis were constructed as a group of ITFS diastasis. On the models of ITFS diastasis, elastic fixation with transverse Tightrope system (transverse fixation group) or binding Tightrope system (binding fixation group) was applied. The reduction and stability of ITFS were compared between transverse fixation and binding fixation for ITFS diastasis in terms of ITFS parameters on X-Ray[tibiofibular clear space (TFCS) and medial clear space (MCS)] and on CT[inferior tibiofibular anterior clear space (ITFACS), inferior tibiofibular middle clear space (ITFMCS), inferior tibiofibular posterior clear space (ITFPCS), anterior inferior tibiofibular interval (AITFI) and fibular rotation (θfib)].Results:The transverse fixation with Tightrope system for ITFS diastasis on the models led to iatrogenic injury to the fibular and the ITFS interosseous ligaments and to the perforating peroneal artery, and malreduction as well while the binding fixation with Tightrope system caused no injury to the anterior or the posterior ITFS ligament or the superior peroneal retinaculum but fine reduction as well. In comparisons of TFCS, ankle MCS, ITFACS, ITFMCS and AITFI between the 4 groups, normal ITFS group<binding fixation group<transverse fixation group<ITFS diastasis group; in comparison of ITFPCS between the 4 groups, transverse fixation group<binding fixation group<normal ITFS group< ITFS diastasis group; in comparison of θfib between the 4 groups, normal ITFS group<binding fixation group< ITFS diastasis group< transverse fixation group. Significant differences were shown in all the pairwise comparisons ( P<0.05). Conclusion:The binding fixation with our self-designed Tightrope system may be superior to the transverse fixation in surgical approach and reduction and stability of ITFS.