“Flexible nature of fixation” in syndesmotic stabilization of the inferior tibiofibular joint affects the radiological reduction outcome

Risk factors associated with breakage of tibio-fibular syndesmotic screws

PURPOSE

This retrospective study aimed to investigate the factors associated with the breakage of tibio-fibular syndesmotic screws (SS).

METHODS

69 patients with unstable AO-Weber Type 44-B ankle fractures who underwent three cortex SS (3.5 mm ø) fixation were included. Patients were followed for at least one year (mean, 18.3 ± 7.6 months). At the final follow-up, patients with broken (Group I) and intact (Group II) SS were compared regarding age, gender, height, weight, body mass index, fracture type, SS length, location, and orientation. Multivariate logistic regression was used to identify the independent risk factors associated with SS breakage. The sensitivity, specificity, cut-off value, and area under the ROC curve were analyzed.

RESULTS

A stepwise backward logistic regression analysis revealed that age was the only independent predictor for SS breakage (OR = 0.938, 95% CI = 0.904-0.973, R2 = 0.270). ROC curve analysis demonstrated that patients younger than 36 years were associated with seven times increased risk of SS breakage [Odds ratio (95% CI), 7.042 (2.251-22.031)].

CONCLUSION

Age under 36 years was the only significant risk factor for SS breakage. The higher incidence of breakage of the syndesmotic screw can be informed to patients younger than 36.

A 3-Ligament Syndesmotic Injury Is at Higher Risk for Malreduction Than a 2-Ligament Injury: A CT-Based Analysis

BACKGROUND

Syndesmotic malreduction is common and has been associated to an impaired outcome. Various risk factors for DTFJ malreduction have been postulated. The aims of this study were to assess the DTFJ malreduction rate based on (1) the severity of the syndesmotic injury, (2) the anatomy of the tibial incisura, and (3) the fixation device used in patients treated with suture-button systems.

METHODS

This retrospective, radiographic study included all adult patients who were treated for an acute, unilateral, and unstable syndesmotic injury with a suture-button system and postoperative bilateral CT imaging. Included were isolated syndesmotic injuries and fracture cases. The number of syndesmotic ligaments injured, that is, 2-ligament (AiTFL+IOL) and 3-ligament (AiTFL+IOL+PiTFL), was rated for each patient. The quality of DTFJ reduction, as well as the anatomy of the tibial incisura, was rated based on the postoperative, bilateral CT images and the intraoperative DTFJ reduction was recalculated based on the drilling-tunnel deviation. The possible influence on the DTFJ malreduction rate was assessed.

RESULTS

A total of 147 patients were included, and 94 and 53 patients had a 2- and 3-ligament syndesmotic injury, respectively. In addition, 113 patients were treated with a single-button system, 26 with a double suture-button system, and 8 with a hybrid fixation (suture-button + screw). Malreduction was significantly higher in 3-ligament compared with 2-ligament injuries, both intraoperatively (51% vs 27%; P = .003) and postoperatively (28% vs 11%; P = .006). The tibial anatomy had no significant influence on the malreduction rates. No significant differences were seen per the different fixation devices used independent of the number of ligaments injured.

CONCLUSION

This study did not find an influence of the incisura's anatomy on the DTFJ malreduction rate. However, we did find that 3-ligament syndesmotic injuries carried a higher risk of intra- and postoperative malreduction compared with 2-ligament injuries.

LEVEL OF EVIDENCE

Level III, retrospective radiologic study.

Meta-analysis of elastic versus rigid fixation in the treatment of acute tibiofibular syndesmosis injury

OBJECTIVE

The objective of this study was to conduct a meta-analysis by synthesizing multiple literature sources to explore whether there are any differences between elastic fixation and rigid fixation in the treatment of acute tibiofibular syndesmosis injuries. The aim was to provide effective guidance for clinical treatment.

METHODS

We conducted a comprehensive search across seven databases, including both Chinese and English, to include all studies related to the treatment of acute tibiofibular syndesmosis injuries with elastic fixation and rigid fixation published between January 1, 2013, and November 15, 2022. Following the PRISMA guidelines, we rigorously screened, assessed, and extracted data from the included studies. The outcome measures included AOFAS scores at 3, 6, and 12 months postoperatively; tibiofibular clear space (TBCS) and tibiofibular overlap distance (TBOL) at the early postoperative and 12-month follow-up; intraoperative blood loss; operative time; time to full weight-bearing postoperatively; and postoperative complications. Meta-analysis was performed using Review Manager 5.4.

RESULTS

A total of 35 studies were included, comprising 16 randomized controlled trials and 19 retrospective cohort studies. The study population included 2120 cases, with 1044 cases in the elastic fixation group and 1076 cases in the rigid fixation group. The elastic fixation group had higher AOFAS scores at 3, 6, and 12 months postoperatively compared to the rigid fixation group. Although the elastic fixation group had a slightly larger TBCS than the rigid fixation group in the early postoperative period, the difference between the two groups became statistically insignificant at 12 months postoperatively. There was no statistically significant difference in TBOL between the two groups in the early postoperative period, but at 12 months, the elastic fixation group had a greater TBOL than the rigid fixation group. Additionally, the elastic fixation group had lower rates of postoperative local irritation, wound infection, and postoperative internal fixation loosening or rupture compared to the rigid fixation group. The rate of postoperative tibiofibular redislocation did not differ statistically between the two groups. The time to full weight-bearing was shorter in the elastic fixation group than in the rigid fixation group. Although the elastic fixation group had a slightly longer operative time, there was no statistically significant difference in intraoperative blood loss between the two groups.

CONCLUSION

Compared to rigid fixation, elastic fixation in the treatment of acute tibiofibular syndesmosis injuries offers several advantages, including better postoperative ankle joint function recovery, more precise anatomical reduction of the syndesmosis postoperatively, a lower incidence of postoperative complications, and shorter time to full weight-bearing postoperatively. These findings provide robust guidance for clinical treatment.