ObjectiveTo evaluate the biomechanical characteristics and effectiveness of repairing anteroinferior tibiofibular ligament and fixing the posterior malleolar fracture in reconstructing syndesmotic stability after ankle fracture of pronation-external rotation type (PER) stage IV. MethodsTwenty-four normal lower extremity cadaver specimens were collected and made into intact ankle specimens. A MTS Bionix 858 test system was used to measure the maximum rotation of the foot under a static axial load of 150 N, internal rotation torque to the tibia at a rate of 1°/second and 4 N·m torque. Then a fracture of PER stage IV model was established in each specimen. Internal fixation of lower tibiofibular ligament union was performed by screws in group A, fixation of posterior malleolar fractures in group B, fixing posterior malleolar fracture combined with repairing anteroinferior tibiofibular ligament in group C (8 specimens each group). Then the maximum rotation of the foot was measured under the same condition, and the syndesmotic stability was calculated. Between July 2009 and September 2012, 32 patients with ankle fracture of PER stage IV were treated. There were 19 males and 13 females with an average age of 35 years (range, 20-63 years). The locations were the left ankle in 14 cases and the right ankle in 18 cases. The time from injury to admission was 3.5 hours on average (range, 1-72 hours). Open reduction and plate compression internal fixation were performed in fibula, and medial malleolus was fixed by conpression screws, then anteroinferior tibiofibular ligament was mended and posterior malleolar fracture was fixed by screws. ResultsThe preservation rates of syndesmotic stability after repair were 46.2%±12.3%, 62.6%±10.7%,and 66.5%±12.6% in groups A, B,and C, respectively; groups B and C were significantly superior to group A (P<0.05),but no significant difference was found between groups B and C (P>0.05). All patients achieved wound healing by first intention, and were followed up 12-24 months (mean,15 months). All fractures healed,with an average healing time of 11.2 weeks (range, 10-14 weeks) on the X-ray films. No seperation of inferior tibiofibular syndesmosis was observed during the follow-up period. American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score was 88.4 on average (range, 61-98) at last follow-up; the results were excellent in 13 cases,good in 15 cases, and fair in 4 cases, with an excellent and good rate of 87.5%. ConclusionIn patients with ankle fracture of PER stage IV, a combination of fixing the posterior malleolar fracture and repairing anteroinferior tibiofibular ligament can reconstruct syndesmotic stability effectively.
Objective To study the effectiveness of TightRope elastic fixation combined with functional total repair of the inferior tibiofibular ligament in the treatment of distal tibiofibular syndesmosis injury. Methods The clinical data of 34 patients with distal tibiofibular syndesmosis injury who met the selection criteria between January 2020 and January 2022 were retrospectively analyzed, and they were divided into improved group (TightRope elastic fixation combined with functional total repair of inferior tibiofibular ligament) and control group (distal tibiofibular screw fixation) according to the surgical methods, with 17 cases in each group. There was no significant difference in age, gender, body mass index, fracture type, and other baseline data between the two groups (P>0.05). The operation time, intraoperative blood loss, and complications were recorded in the two groups. The American Orthopaedic Foot and Ankle Society (AOFAS) score, ankle metatarsal flexion and dorsal extension range of motion were used to evaluate the ankle function. The patient satisfaction survey was conducted at last follow-up. Results All 34 patients were followed up 8-20 months, with a median of 13 months. The operation time and intraoperative blood loss in the improved group were significantly longer than that in the control group (P<0.05). In the improved group, no infection or poor reduction occurred, and only 1 patient had TightRope knot reaction at 6 months after operation. In the control group, there were 2 cases of poor reduction, 1 case of lower tibiofibular screw rupture, and 1 case of subcutaneous infection (cured after anti-infection treatment). There was no significant difference in the incidence of complications between the two groups (P>0.05). At last follow-up, the AOFAS score and ankle metatarsal flexion and dorsal extension range of motion of the improved group were significantly better than those of the control group (P<0.05). The satisfaction rates of patients in the improved group and the control group were 94.1% and 82.4%, respectively, showing significant difference (P<0.05). Conclusion TightRope elastic fixation combined with functional total repair of inferior tibiofibular ligament in the treatment of distal tibiofibular syndesmosis injury has sufficient fixation strength, and can achieve better effectiveness and joint function compared with traditional screw fixation.