Anatomically Fixed Posterior Malleolar Fractures in Syndesmosis Injuries without Transsyndesmotic Screw Fixation

Background: The stability of the syndesmosis is extremely important in terms of syndesmosis injury, ankle instability, and posttraumatic osteoarthritis development following ankle fractures. The aim of this study is to evaluate 1-year radiographic outcomes after posterior malleolar fixation in lateral and posterior malleolar fractures and trimalleolar fractures without transsyndesmotic screw fixation. Methods: Ninety-four patients who underwent posterior malleolar fixation with posterolateral approach between January 2017 and June 2019 were evaluated retrospectively. The patients were evaluated with parameters such as demographic characteristics, fracture type, injury mechanism, physical examination, and radiographic measurements. The stability of the syndesmosis was evaluated by an intraoperative Cotton test and by measuring the tibiofibular overlap, tibiofibular clear space, and medial clear space parameters preoperatively on the immediate postoperative, first-year weightbearing ankle anteroposterior radiographs. Results: In immediate postoperative measurements on radiographs, although the mean tibiofibular overlap ( P < .001) increased, the mean tibiofibular clear space ( P < .001) and mean medial clear space ( P < .001) decreased compared with preoperative radiographs. Immediate postoperative mean tibiofibular overlap, tibiofibular clear space, and medial clear space compared with postoperative first-year mean tibiofibular overlap ( P = .39), tibiofibular clear space ( P = .23), and medial clear space ( P = .43) were not statistically significant. Bone union was completed radiographically at a median of 3.4 ± 1.8 months after surgery. Conclusion: After posterior malleolar fractures, anatomic reduction of the posterior malleolus and posterior inferior tibiofibular ligament complex provides strong syndesmosis stability as measured radiographically at 1 year. Patients may not need additional transsyndesmotic screw fixation. Level of Evidence: Level IV, case series.

Morphological analysis of posterior malleolar fractures with intra-articular impacted fragment in computed tomography scans

Background Intraarticular impacted fragment (IAIF) of posterior malleolar fractures has been reported by a few studies. However its location, morphology, and the correlation of posterior malleolar fractures have not been described in detail. The aim of this study was to describe the morphology of IAIF in posterior malleolar fractures, to analyze the related factors between IAIF and posterior malleolar fragments, and explore the treatment of IAIF. Materials and methods Between January 2013 and December 2018, 108 consecutive patients with unilateral posterior malleolar fractures were managed in our hospital. Basic demographic and computed tomography (CT) data were collected and classified by Lauge–Hansen, OTA/AO, Haraguchi, and Mason classification. Additional radiographic data, including the length and area of posterior malleolar fragment, IAIF, and stable tibial plafond were measured. The location of IAIF was described, and involvement of the fibular notch and medial malleolus was also observed. Statistics were analyzed based on univariate analysis (Chi-square test, t-test, Mann–Whitney U test, Fisher’s test) and Spearman’s correlation test. Results Among the 108 cases of posterior malleolar fractures, 75 (69.4%) were with IAIF and 33 (30.6%) cases were without. There were 74 (68.5%) females and 34 (31.5%) males, and the average age of the patients was 49 years (18–89 years). The average LIFN/(LIFN + LSFN) [length of involving fibular notch/(length of involving fibular + length of stable notch fibular notch)] was 32.9% (11.6–64.9%). The APMF/(APMF + ASTP + AIAIF) [area of posterior malleolar fragment/(area of posterior malleolar fragment + area of IAIF + area of stable tibial plafond)] and AIAIF/APMF (area of IAIF/area of posterior malleolar fragment) were 13.1% (0.8–39.7%) and 52.6% (1.2–235.4%), respectively. Involvement of medial malleolus (fracture line extended to medial malleolus, P = 0.022), involvement of fibular notch (P = 0.021), LIFN/(LIFN + LSFN) (P = 0.037), LMPMF (P = 0.004), and APMF were significantly related to the occurrence of IAIF. Conclusion Our research indicates a high incidence of IAIF in posterior malleolar fractures. All IAIFs were found in posterior malleolar, and the most common location was within the lateral area A. Posterior malleolar fracture lines that extend to medial malleolus or fibular notch herald the incidence of IAIF. LIFN/(LIFN + LSFN), LMPMF and APMF are also associated with the incidence of IAIF. CT scans are useful for posterior malleolar fractures to determine the occurrence of IAIF and make operational plans. Operation approach selection should be based on the morphology of posterior malleolar fragments and the location of IAIF. Level of evidence Level III, retrospective case analysis.

Lateral Trans-Malleolar Approach for Posterior Malleolar Fractures of the Ankle for Articular and Syndesmosis Reduction : A Retrospective Study

Background The lateral transmalleolar approach (LTA) is a surgical approach for posterior malleolar fractures (PMFs), providing direct visualization of the articular surface of the posterior malleolus, though temporarily disrupting the syndesmosis. However, it is still unclear whether this fibrous joint can be effectively reconstructed afterward to prevent complications. We report the clinical results and computed tomography (CT) findings for articular and syndesmosis reduction status after surgery with LTA for PMF. Methods Sixteen patients who underwent PMF reduction with LTA and were followed up for at least 1 year were evaluated retrospectively. According to the AO/OTA classification, the fracture type was type 44B in 13 patients and 44C in three patients. The Haraguchi classifications of PMF were type 1 in six cases and type 2 in 10 cases. The American Orthopedic Foot and Ankle Society Ankle-Hindfoot Scale (AOFAS) score, post-surgical complications, and reduction status of PMF and syndesmosis on CT were investigated. Results The mean AOFAS score was 93.0 ± 5.2 points. Post-operative complications were observed in one case of superficial infection and one case of delayed fibular union. The articular step-off seen on CT improved significantly after surgery (5.9 ± 2.9 mm preoperatively vs. 0.6 ± 0.8 mm post-operatively). Syndesmosis malreduction was seen in three cases, including two high fibular fractures and one comminuted fibular fracture with osteoporosis. Conclusions The LTA provided favourable clinical results and effective reduction of intra-articular PMFs. However, surgeons should be aware of the possibility of syndesmosis malreduction in cases of high fibular fractures or comminuted fibular fractures.