Comparison of Ankle Fracture Fixation Using Intramedullary Fibular Nailing Versus Plate Fixation.

Ankle fracture fixation using intramedullary fibular (IMF) nails has been shown to allow for earlier weightbearing, reduced wound complications, better union rates, and the absence of prominent hardware, compared to plates/screw (PS) constructs. The purpose of present retrospective cohort study was to compare outcomes of patients who underwent ankle fracture fixation using an IMF nail versus PS. Demographic, clinical, and radiographic data were recorded for patients who underwent ankle fracture fixation between May 2020 and May 2022, and who were at least 1 year postoperative. Toe-touch weightbearing was permitted immediately after surgery, protected weightbearing (PWB) at postoperative week 2, and weightbearing as tolerated in a brace at week 6. Radiographs were assessed preoperatively, and at 2, 6, 12, 24, and 48 weeks postoperative. Sixty-one ankle fractures (30 IMF, 31 PS) with a mean follow up of 14.7 and 18 (range, 12 to 23) months were included. Overall, the IMF nail cohort had less pain, faster time to union (11.4 vs 13.2 weeks), and less complications (23% vs 45%), reoperations (10% vs 16%), and surgical failures (9% vs 9.7%), compared to the PS cohort. The differences were not statistically significant. The PS cohort had a higher rate of symptomatic hardware irritation (p =< .001). Tobacco use adversely effected direct osseous healing (p < .001) and increased postoperative complications (p = .050). The present study lends credence to the previously reported advantages of IMF nailing over PS fixation for ankle fractures. Ankle fracture fixation using a fourth generation, IMF nail is a viable alternative to traditional PS fixation.

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.

Syndesmotic screws, unscrew them, or leave them? A systematic review and meta-analysis of randomized controlled trials.

Background: Syndesmotic injuries are frequently stabilized using syndesmotic screws. Traditionally, these screws were routinely removed during the postoperative period, however recent literature has brought into question the necessity of routine removal, citing no change in functional outcomes and the inherent risks of a second surgery. Our study aimed to compare outcomes of patients undergoing routine syndesmotic screw removal versus those undergoing an on-demand approach to removal. Methods: A systematic search of studies comparing routine syndesmotic screw removal to on-demand screw removal following an acute ankle fracture, or an isolated syndesmotic injury was conducted across seven databases. Only Prospective randomized controlled trials were eligible for inclusion. Data reported on by at least 2 studies was pooled for analysis. Results: Three studies were identified that met inclusion and exclusion criteria. No significant difference in Olerud-Molander Ankle Score (MD -2.36, 95% CI -6.50 to 1.78, p = 0.26), American Orthopedic Foot and Ankle Hindfoot Score (MD -0.45, 95% CI -1.59 to .69, p = 0.44), or dorsiflexion (MD 2.20, 95% CI -0.50 to 4.89, p = 0.11) was found between the routine removal group and on-demand removal group at 1-year postoperatively. Routine removal was associated with a significantly higher rate of complications than on-demand removal (RR 3.02, 95% CI 1.64 to 5.54, p = 0.0004). None of the included studies found significant differences in pain scores or range of motion by 1-year postoperatively. Conclusion: Given the increased risk of complications with routine syndesmotic screw removal and the comparable outcomes when screws are retained, an as-needed approach to syndesmotic screw removal should be considered.

The Use of Blocking Wires in Fibular Intramedullary Nailing of an Ankle Fracture with Hardware Failure: A Case Report.

A 24-year-old male, with a body mass index (BMI) of 31.7 and a previous open reduction and internal fixation (ORIF) of the left ankle seven years ago, presented to the emergency department with a peri-implant, comminuted fibula fracture with broken hardware and syndesmotic injury. The nature of the revision surgery made proper guidewire placement during fibular nailing difficult. Blocking wires assisted in ensuring proper guidewire placement. The patient was successfully managed with revision ORIF, fibular nailing, and syndesmotic fixation. Blocking wires are a helpful tool for achieving proper fracture alignment and stability during intramedullary nailing procedures and may be considered in fibular nailing situations.

The Clinical Outcomes of Syndesmotic Flexible Fixation for Syndesmotic Injury With Ankle Fracture.

BACKGROUND: We evaluated whether the quality of syndesmotic reduction affects the short-term clinical outcomes of flexible fixation in patients with a rotational ankle fracture. METHODS: This study included 59 patients (32 men and 27 women) who underwent syndesmotic flexible fixation. The degree of syndesmotic reduction was evaluated on computed tomography (CT) images acquired within 3 days after surgery. We measured the divergence between anterior and posterior incisura at 1 cm above the distal tibial articular joint, then evaluated the degree of fibular rotation relative to the tibia. At 1 year after surgery, an objective clinical evaluation was performed using the American Orthopaedic Foot & Ankle Society (AOFAS) score, the visual analog scale (VAS), and the Foot and Ankle Outcome Score (FAOS). Additionally, repeat arthroscopy was performed during routine implant removal at nearly 1 year postoperatively. RESULTS: Among 59 patients who underwent syndesmotic flexible fixation, 56 patients had syndesmotic stability on repeat arthroscopy. At 1 year postoperation, AOFAS, VAS, and FAOS scores were, respectively, 90, 2.0, and 94 in the accurate reduction group (n = 24) and 90, 1.0, and 94.5 in the malreduction group (n = 35). CONCLUSION: Reduction quality after syndesmotic injury with flexible fixation, as determined by early postoperative CT imaging, did not affect patient prognosis. In this cohort, syndesmotic reduction and flexible fixation may produce good clinical outcomes in patients with syndesmotic injury and ankle fracture. LEVEL OF EVIDENCE: Level III, retrospective cohort study.

Influence of quality of reduction using radiological criteria on kinematics and kinetics in ankle fractures with unstable syndesmotic injury.

BACKGROUND: In ankle fractures with syndesmotic injury, the anatomic reduction of the ankle mortise is crucial for preventing osteoarthritis. Yet, no studies have analysed the effect of surgical reduction after unstable ankle fractures on patients' active functional outcome. METHODS: The Intraoperative 3D imaging data of patients surgically treated between 2012 and 2019 for ankle fracture with concomitant syndesmotic injury were reviewed. 58 patients were allocated to two groups depending on whether the criteria for radiologically optimal reduction were met (39 patients) or not (19 patients). Criteria for optimal reduction were composed of objectively measured and subjectively rated data. After undertaking the Olerud/Molander ankle score, a gait analysis and several active function tests using 3D motion capture were performed in order to evaluate kinetic and kinematic differences between both groups. FINDINGS: Patients showed deficits of range of motion and balance parameters on the injured ankle, however, there were no significant differences between both groups. INTERPRETATION: Although, the data did not show that radiological reduction criteria have a statistically significant effect on active functional outcome after a mean follow up time of 5.7 years, tendencies for a better outcome of patients that met the criteria could be seen. It also must be taken into consideration that results are limited by case number and allocation ratio, which made a sub-analysis of the separate reduction criteria unfeasible.

Short and Middle Functional Outcome in the Static vs. Dynamic Fixation of Syndesmotic Injuries in Ankle Fractures: A Retrospective Case Series Study.

BACKGROUND: Syndesmotic injuries are common lesions associated with ankle fractures. Static and dynamic fixation are frequently used in syndesmotic injury-associated ankle fractures. The purpose of this study is to compare short- and mid-term quality of life, clinical outcomes, and gait after static stabilization with a trans-syndesmotic screw or dynamic stabilization with a suture button device. METHODS: Here, 230 patients were enrolled in a retrospective observational study. They were divided in two groups according to the fixation procedure (Arthrex TightRope®, Munich, Germany) synthesis vs. osteosynthesis with a 3.5 mm trans-syndesmotic tricortical screw). They then underwent clinical assessment using the American Foot and Ankle Score (AOFAS) at 1, 2, 6, 12, and 24 months after surgery. Quality of life was assessed according to the EuroQol-5 Dimension (EQ-5D) at 2 and 24 months after surgery in the follow-up; gait analysis was performed 2 and 24 months postoperatively. RESULTS: Significant differences were found at a two-month follow-up according to the AOFAS (p = 0.0001) and EQ-5D (p = 0.0208) scores. No differences were noted in the other follow-ups (p > 0.05) or gait analysis. CONCLUSION: The dynamic and static fixation of syndesmotic injuries in ankle fracture are both efficacious and valid procedures for avoiding ankle instability. The suture button device was comparable to the screw fixation according to functional outcomes and gait analysis.

Diagnostic Accuracy of Conventional Ankle CT Scan With External Rotation and Dorsiflexion in Patients With Acute Isolated Syndesmotic Instability.

BACKGROUND: Syndesmotic injury in an athletic population is associated with a prolonged ankle disability after an ankle sprain and often requires a longer recovery than a lateral collateral ligament injury. Although several imaging tests are available, diagnosing syndesmotic instability remains challenging. PURPOSE: To determine the diagnostic accuracy of conventional ankle computed tomography (CT) scans with the joint in external rotation and dorsiflexion and compare it with that of conventional ankle CT scans in a neutral position. STUDY DESIGN: Cohort study (Diagnosis); Level of evidence, 2. METHODS: Between September 2018 and April 2021, this prospective study consecutively included adults visiting the foot and ankle outpatient clinic with a positive orthopaedic examination for acute syndesmotic injury. Participants underwent 3 CT scan tests. First, ankles were scanned in a neutral position. Second, ankles were scanned with 45° of external rotation, dorsiflexion, and extended knees. Third, ankles were scanned with 45° of external rotation, dorsiflexion, and flexed knees. Three measurements, comprising rotation (measurement a), lateral translation (measurement c), and anteroposterior translation (measurement f) of the fibula concerning the tibia, were used to diagnose syndesmotic instability in the 3 CT scans. Magnetic resonance imaging was used as a reference standard. The area under the curve (AUC) was used to compare the diagnostic accuracy, and Youden's J index was calculated to determine the ideal cutoff point. RESULTS: Images obtained in 68 participants (mean age, 36.5 years; range, 18-69 years) were analyzed, comprising 36 syndesmotic injuries and 32 lateral collateral ligament injuries. The best diagnostic accuracy occurred with the rotational measurement a, in which the second and third CT scans with stress maneuvers presented greater AUCs (0.97 and 0.99) than did the first CT scan in a neutral position (0.62). The ideal cutoff point for the stress maneuvers was 1.0 mm in the rotational measurement a and reached a sensitivity and specificity of 83% and 97% for the second CT scan with extended knees and 86% and 100% for the third CT scan with flexed knees, respectively. The ideal cutoff point for the first CT scan with a neutral position was 0.7 mm in the rotational measurement a, with a sensitivity of 25% and specificity of 97%. CONCLUSION: Conventional ankle CT with stress maneuvers has excellent performance for diagnosing subtle syndesmotic rotational instability, as it shows a greater AUC and enhanced sensitivity at the ideal cutoff point compared with ankle CT in the neutral position.

Comparison of Suture Button and Syndesmotic Screw for Ankle Syndesmotic Injuries: A Meta-analysis of Randomized Controlled Trials.

Background: The syndesmotic screw (SS) and suture button (SB) fixation methods are both widely used for the reduction of ankle syndesmotic injury, with varying outcomes. Purpose: To review recently published randomized controlled trials (RCTs) to assess the outcomes between SS and SB fixation for ankle syndesmotic injury. Study Design: Systematic review; Level of evidence, 1. Methods: The PubMed, Embase, ClinicalTrials.gov, and Cochrane databases were searched for relevant RCTs published between 1966 and 2021 according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Eligible studies were RCTs comparing SS and SB fixation for ankle syndesmotic injury. The risk of bias was evaluated using the Cochrane Risk of Bias tool. Primary outcomes included complications, malreduction, and unplanned reoperation, and secondary outcomes were the American Orthopaedic Foot & Ankle Society (AOFAS) score, Olerud-Molander ankle score (OMAS), and EuroQol-5 Domain (EQ-5D) score. The mean difference (MD) and risk ratio (RR) were calculated for continuous and dichotomous outcomes, respectively. Random- or fixed-effects model was applied according to heterogeneity. Results: Of 389 studies, 8 RCTs involving 512 patients were included. Overall, 257 patients received SS fixation and 255 patients received SB fixation. The 2 groups did not differ significantly in malreduction (RR, -0.06; 95% CI, -0.18 to 0.07) or EQ-5D (MD, 0.01; 95% CI, -0.01 to 0.03). However, the SB group showed significant advantages over the SS group in complications (RR, 0.42; 95% CI, 0.26 to 0.66), unplanned reoperation (RR, 0.62; 95% CI, 0.43 to 0.89), AOFAS score (MD, 3.04; 95% CI, 1.77 to 4.31), and OMAS (MD, 4.51; 95% CI, 1.54 to 7.48). The risk of bias of the included studies was acceptable. Conclusion: The results showed that there were no significant differences between the SS and SB groups in malreduction and EQ-5D scores. However, the SB group had significantly better local irritation rates, unplanned reoperation rates, AOFAS scores, and OMASs.

Safe drilling zones for anteriorly, central, and posteriorly angulated syndesmotic stabilization devices.

PURPOSE: The purposes of the study were to (1) analyze the shape of the distal fibula at the location of syndesmotic stabilization and to (2) define safe zones at the distal-lateral fibula for three different drilling tunnel orientations: anteriorly-, posteriorly angulated and center-center. METHODS: Postoperative, bilateral CT images of adult patients that underwent syndesmotic stabilization (suture-button system) for an acute, unilateral ankle injury were analyzed. Manual axial CT reconstructions of the uninjured side were generated. First, the axial shape of the distal fibula was classified. The aspect ratio between the anterio-lateral and the posterior-lateral surfaces of the fibula was calculated to assess symmetry. Second, the same axial planes were used to define the safe zones. Each drilling-tunnel orientation (anterior, central, posterior) comprised a fixed medial tibial anchor point and a safe zone on the lateral fibula. For each of the three orientations, the most anteriorly and posteriorly drilling tunnel location was simulated. Next to a cumulative visual analysis, a quantitative analysis of the most anterior and posterior point on the anterio- and posterior-lateral surfaces was calculated. RESULTS: A total of 96 CT datasets were analyzed. (1) 81% of fibulae revealed a triangular convex-, 10% an irregular-, and 8% a quadrilateral shape. The lateral surface ratio was 1.0 ± 0.2 (range: 0.7-1.5), not differing between the fibula types (n.s.). (2) The safe corridor on the lateral surface of the fibula for an anteriorly angulated drilling tunnel was - 8% to - 41%, for a posteriorly angulated drilling tunnel was 0% to 46%, and for a center-center alignment - 7 ± 11% (range: - 28 to 18%). CONCLUSION: The meta-diaphyseal region of the distal fibula revealed a homogeneous crosssectional shape. The lateral apex of the fibula can serve as a landmark defining safe zones to place the drilling tunnels correctly. Applying these safe zones in clinical practice could help to avoid the misplacement of the syndesmotic fixation device. LEVEL OF EVIDENCE: Level III, retrospective radiographic study.

Current status of the management of isolated syndesmotic injuries in Germany.

INTRODUCTION: Although non-fracture-related syndesmotic injuries of the ankle are relatively rare, they may lead to poor clinical outcome if initially undiagnosed or managed improperly. Despite a variety of literature regarding possibilities for treatment of isolated syndesmotic injuries, little is known about effective applications of different therapeutic methods in day-to-day work. The aim of this study was to assess the current status of the treatment of isolated syndesmotic injuries in Germany. MATERIALS AND METHODS: An online-questionnaire, capturing the routine diagnostic workup including clinical examination, radiologic assessment and treatment strategies, was sent to all members of the German Society of Orthopedic Surgery and Traumatology (DGOU) and Association of Arthroscopic and Joint Surgery (AGA). Statistical analysis was performed using Microsoft excel and SPSS. RESULTS: Each question of the questionnaire was on average answered by 431 ± 113 respondents. External rotation stress test (66%), squeeze test (61%) and forced dorsiflexion test (40%) were most commonly used for the clinical examination. In the diagnostic workup, most clinicians relied on MRI (83%) and conventional X-ray analysis (anterior-posterior 58%, lateral 41%, mortise view 38%). Only 15% of the respondents stated that there is a role for arthroscopic evaluation for the assessment of isolated syndesmotic injuries. Most frequently used fixation techniques included syndesmotic screw fixation (80%, 42% one syndesmotic screw, 38% two syndesmotic screws), followed by suture-button devices in 13%. Syndesmotic screw fixation was mainly performed tricortically (78%). While 50% of the respondents stated that syndesmotic screw fixation and suture-button devices are equivalent in the treatment of isolated syndesmotic injuries with respect to clinical outcome, 36% answered that syndesmotic screw fixation is superior compared to suture-button devices. CONCLUSIONS: While arthroscopy and suture-button devices do not appear to be widely used, syndesmotic screw fixation after diagnostic work-up by MRI seems to be the common treatment algorithm for non-fracture-related syndesmotic injuries in Germany.

How we do it? Trimalleolar Fractures: Posterolateral Approach for Fixing the Syndesmotic Ligament, Posterior Malleolus, and Fibula.

Introduction: Syndesmotic injury in trimalleolar fracture is necessary to address intraoperatively by stability test, as it affects post-operative functional outcomes. Most of syndesmotic injuries are stable after fixation of the posterior malleolus, but in rare cases, syndesmosis is not stable after adequate fixation. In those rare conditions, we have to fix syndesmosis by corticocancellous (CC) screw throw lateral fibula plate. We emphasize this complex problem and offer solutions to overcome it. Case Report: Case 1: A 45-year-old male suffered significant trauma to his right ankle from a slip and fall, resulting in a trimalleolar fracture. The open reduction and internal fixation (ORIF) throw posterolateral approach was performed after wrinkles were seen on the ankle. A four-hole Ellis plate was used in antiglide mode to reduce posterior malleolar fragments. The lateral malleolus is fixed with a 7-hole, 1/3-locking tubular plate with a tricortical syndesmotic CC screw. The medial malleolus was internally fixed by a 6-hole LC-DCP. Case 2: A 49-year-old female suffered significant trauma to her right ankle from a domestic fall, resulting in a trimalleolar fracture. The ORIF throw posterolateral approach was performed after wrinkles were seen on the ankle. A four-hole Ellis plate was used in antiglide mode to reduce posterior malleolar fragments. The lateral malleolus is fixed with an 8-hole, 1/3-locking tubular plate with a tricortical syndesmotic CC screw. The medial malleolus was internally fixed by a 2 CC screw with an 8-hole LC-DCP. The anterior distal tibia fragment was fixed with a 16-mm anteroposterior CC screw. Conclusion: In a trimalleolar ankle fracture, fixation of the posterior malleolus is important for a better post-operative functional outcome, irrespective of the size of the posterior malleolus. The author recommends lateral fibula plate fixation by creating a window between the skin and the peroneus longus and brevis tendon, so we have a chance to put a syndesmotic screw into the lateral plate if syndesmosis is not stable.

A systematic review and meta-analysis on the value of the external rotation stress test under fluoroscopy to detect syndesmotic injuries.

Purpose: The aim was to conduct a systematic literature review and meta-anaylsis to analyze the diagnostic accuracy of the external rotation stress test (ERST) for syndesmotic injuries. Methods: The systematic review was conducted according to the PRISMA-P guidelines (Prospero ID: CRD42021282457). Four common databases were searched from inception to September 29, 2021. Eligible were any studies facilitating the ERST under fluoroscopy in a defined state of syndesmotic instability. Syndesmotic ligament-specific rupture must have been proven by MRI, arthroscopy, or controlled dissection (cadaver study). Two reviewers independently conducted each step of the systematic literature review. The risk of bias was assessed by the Quality Appraisal for Cadaveric Studies Score scale. The data analysis was performed qualitatively and quantitatively. Results: Eight studies were eligible for a qualitative analysis, and six studies were eligible for a quantitative analysis. All studies included were cadaver studies. The qualitative analysis comprised 94 specimens and revealed considerable heterogeneity. Six studies allowed for a quantitative analysis of the tibiofibular clear space (TFCS) and five studies for the medial clear space (MCS) during the ERST. The quantitative analysis of the TFCS revealed no significant differences between intact and any stage of syndesmotic injury. The MCS was able to differentiate between intact and 2-ligament- (Z = 2.04, P = 0.02), 3-ligament- (Z = 3.2, P = 0.001), and 3-ligament + deltoid ruptures (Z = 3.35, P < 0.001). Conclusion: The ERST is the only noninvasive test to assess syndesmotic instability and can be conducted bilaterally. The uninjured contralateral side can serve as a baseline reference. Based on the conducted quantitative analysis, the MCS seems to be able to differentiate between stable (intact/1-ligament) and unstable (2-ligament/3-ligament) lesions.

Comparison of Treatment Methods for Syndesmotic Injuries With Posterior Tibiofibular Ligament Ruptures: A Cadaveric Biomechanical Study.

Background: Studies on ankle syndesmosis have focused on anterior inferior tibiofibular ligament (AITFL) and interosseous membrane injuries; however, the characteristics of posterior inferior tibiofibular ligament (PITFL) ruptures remain unclear. Purpose/Hypothesis: This study evaluated the biomechanical characteristics of syndesmotic instability caused by PITFL injury and compared various treatment methods. We hypothesized that PITFL injury would lead to syndesmotic internal rotational instability and that the stability would be restored with suture tape (ST) PITFL augmentation. Study Design: Controlled laboratory study. Methods: Ten uninjured fresh-frozen cadaveric leg specimens were tested via forces applied to the external and internal rotation of the ankle joint. The fibular rotational angle (FRA) related to the tibia, anterior tibiofibular diastasis (aTFD), and posterior tibiofibular diastasis (pTFD) were measured using a magnetic tracking system. Six models were created: (1) intact, (2) AITFL injury; (3) AITFL + PITFL injury; (4) suture button (SB) fixation; (5) SB + anterior ST (aST) fixation; and (6) SB + aST + posterior ST fixation. The FRA, aTFD, and pTFD were statistically compared between the intact ankle and each injury or fixation model. Results: In the intact state, the changes in FRA and aTFD were 1.09° and 0.33 mm when external rotation force was applied and were 0.57° and 0.41 mm when internal rotation force was applied. In the AITFL injury model, the changes in FRA and aTFD were 2.38° and 1.51 mm when external rotation force was applied, which were significantly greater versus intact (P = .032 and .008, respectively). In the AITFL + PITFL injury model, the changes in FRA and pTFD were 2.12° and 1.02 mm when internal rotation force was applied, which were significantly greater versus intact (P = .007 and .003, respectively). In the SB fixation model, the change in FRA was 2.98° when external rotation force was applied, which was significantly higher compared with intact (P < .001). There were no significant differences between the SB + aST fixation model and the intact state on any measurement. Conclusion: PITFL injury significantly increased syndesmotic instability when internal rotation force was applied. SB + aST fixation was effective in restoring syndesmotic stability. Clinical Relevance: These results suggest that SB + aST fixation is sufficient for treating severe syndesmotic injury with PITFL rupture.

Biomechanics comparison between endobutton fixation and syndesmotic screw fixation for syndesmotic injury ankle fracture; a finite element analysis and cadaveric validation study.

Introduction: Various syndesmotic fixation methods in ankle injury are recommended; however, a lack of biomechanical information persists regarding the stiffness of the fixation methods. The current study thus aimed to assess biomechanical cadaveric validation and perform a finite element analysis of syndesmotic fixation comparing endobutton vs. screw after syndesmotic injury with an ankle fracture. Method: Five pairs of ankles of fresh cadavers were used for the validity test for Anterior Inferior Tibiofibular Ligament (AITFL), Posterior Inferior Tibiofibular Ligament (PITFL), and Interosseous ligament biomechanics properties. Four finite element models (FEM) were created: an intact model, a fracture model with/without syndesmotic injury, an endobutton fixation model, and a syndesmotic screw fixation model. Each FEM was tested vis-à-vis external rotation force, anteroposterior translation force, and compression force until model failure. The primary outcomes were stiffness and force until failure. Result: The respective anteroposterior translation force for the stiffness of the intact model, the screw fixation model, and the endobutton fixation was 8.14, 9.15, and 8.17 N/mm. The respective external rotation force for the stiffness of intact, screw fixation, and endobutton model was 0.927,0.949, and 0.940 Nm/degree. The respective stress under compression force in the intact, screw fixation, and endobutton model was 39.94,25.59, and 37.30 MPa. Conclusion: Both screw and endobutton fixation models provided more translation, compression, and rotation stability than normal syndesmosis, but the screw model provided greater translation and compression force stability than the endobutton model. There was no difference in rotational stability between the two models. We thus recommend the same rehabilitation protocol for both fixation methods; however, vigorous translation and compression should be avoided when using endobutton fixation.

Significant variations in surgical construct and return to sport protocols with syndesmotic injuries: an ISAKOS global perspective.

OBJECTIVES: Although the body of literature on syndesmosis injuries is growing with regard to both the biomechanics and clinical outcomes for various fixation constructs, there is little consensus on the optimal treatment and return to sport strategy for these injuries. We endeavoured to assess the current approaches to managing syndesmotic injuries through a Research Electronic Data Capture survey. METHODS: The survey consisted of 27 questions, including respondent demographics, indications for treatment of syndesmotic injuries, preferred treatment and technique, and postoperative management. Responses were generated through six different athlete scenarios: moderate impact, high impact, and very high impact athletes with/without complete deltoid injury. Frequencies and percentages were calculated for all categorical responses. RESULTS: A total of 742 providers responded to the survey, including 457 American surgeons and 285 members of various international societies. Flexible devices were the preferred fixation construct (47.1%), followed by screws (29.6%), hybrid fixation (e.g. combination of flexible device and screw, 18%), and other (5.3%). Sixty-four percent of respondents noted that their rehabilitation protocols would not change for each athlete scenario. Considerable variability was present in anticipated return to full participation, largely dependent on the presence or absence of a deltoid ligament injury. CONCLUSION: The most common elements used as surgical indications were syndesmosis widening > 2 mm on x-ray, an anterior inferior talofibular ligament injury in combination with a posterior inferior talofinular ligament or deltoid ligament involvement on magnetic resonance imaging, and widening of the distal tibiofibular joint during arthroscopic evaluation. Overall, flexible fixation (e.g. suture button) was the preferred device choice for the repair of an injured syndesmosis. Most respondents did not alter their rehab protocol or anticipated return to play timeline based on the injury severity. However, there was considerable variability between respondents on the time to weight-bearing, running, and full participation. Further pragmatic outcomes data are necessary to guide safe return to play protocols for syndesmotic injuries. LEVEL OF EVIDENCE: Level IV.

A 10-Year Follow-Up of Ankle Syndesmotic Injuries: Prospective Comparison of Knotless Suture-Button Fixation and Syndesmotic Screw Fixation.

Background: Acute syndesmosis injury (ASI) is an indication for surgical stabilization if instability is confirmed. In recent years, fixation using the knotless suture-button (SB) device has become increasingly established as an alternative to set screw fixation (SF). This study directly compared the clinical long-term results after prospective randomized inclusion. Materials and Methods: Between 2011 and 2012, 62 patients with ASI were enrolled in a prospective, randomized, and monocentric study. Forty-one patients were available for a 10-year follow-up ((31 males and 10 females), including 21 treated with SB (mean age 44.4 years), and 20 with SF (mean age 47.2 years)). In addition to comparing the demographic data and syndesmosis injury etiology, follow-up assessed the Olerud−Molander Ankle Score (OMAS) and FADI-Score (Foot and Ankle Disability Index Score) with subscales for activities of daily living (ADL) and sports activity. Results: The mean OMAS was 95.98 points (SB: 98.81, SF: 93.00), the mean FADI ADL was 97.58 points (SB: 99.22, SF: 95.86), and the mean FADI Sport was 94.14 points (SB: 97.03, SF: 91.10). None of the measurements differed significantly between the groups (p > 0.05). No clinical suspicion of chronic instability remained in any of the patients, regardless of treatment. Conclusions: The short-term results showed that athletes in particular benefit from SB fixation due to their significantly faster return to sports activities. However, the available long-term results confirm a very good outcome in the clinical scores for both approaches. Chronic syndesmotic insufficiency was not suspected in any of the patients. Level of evidence: I, randomized controlled trial.

Posterior pilon fracture treated by opening the fibula fracture gap.

BACKGROUND: Posterior pilon fracture is a relatively common clinical fracture involving the posterior articular surface of the distal tibia. Currently, this form of fracture is receiving increasing attention. The surgical approach and technique for the treatment of posterior pilon fractures are still controversial. The purpose of this retrospective study was to compare the clinical and imaging outcomes of pilon fractures after treatment with the open fibula fracture line (OFFL) surgical technique versus the traditional posterolateral approach (TPL). METHODS: A retrospective analysis of patients with posterior pilon fractures treated using the open fibula fracture line technique and the traditional posterolateral approach between January 2015 and March 2020. Thirty-one cases were included in the open fibula fracture line technique group and twenty-eight cases were included in the traditional posterolateral approach group. We used the Burwell-Charnley scale to assess the effectiveness of surgical repositioning. The clinical outcomes were evaluated using American Orthopaedic Foot & Ankle Society ankle-hind foot score (AOFAS) and visual analog score (VAS). RESULTS: The overall anatomic reduction rate was slightly better in the open fibula fracture line group than in the conventional posterolateral group (81% vs. 71%, p = 0.406), but there was no statistically significant difference between the two groups. There were no statistically significant differences between the two groups in terms of fracture healing time and time to full weight bearing (p > 0.05). At the final follow-up, the AOFAS functional score of the open fibula fracture line group was statistically superior to that of the conventional posterolateral group (p < 0.05). However, there was no statistical difference between the two groups in VAS pain scores at rest, during activity, and under weight bearing (p > 0.05). CONCLUSION: The trans-fibular fracture approach provides a better surgical option for specific types of posterior pilon fractures with a high rate of anatomic repositioning and a good near-term outcome. TRIAL REGISTRATION: Retrospective registration.

Implications of the Overlapping Degree Between Proximal Fibula and Tibia for Placing the Optimal Syndesmotic Screw: A Virtual Cadaveric Study.

BACKGROUND: To determine the optimal direction of the syndesmotic screw and to introduce a consistent landmark for practical application by analyzing three-dimensional (3D) modeling and virtual implantation. METHODS: A total of 105 cadaveric lower legs (50 males and 55 females; average height, 160.6 ± 7.1 cm) were used to reconstruct a 3D model by using the Mimics® software and the joint morphology was evaluated. Syndesmotic cylinders (Ø3.5 mm/Length 100 mm) were transversely placed in the proximal end of the incisura fibularis for simulating screw fixation. The tibial proximal cylinder, which was tangent to the posterior tibial condyles, was traced and the angle between the two cylinders was measured as the tibial torsion angle (TTA). After rotating the syndesmotic cylinder parallel to the ground, the overlapping degree between the proximal fibula and tibia was assessed as a radiologic indicator. RESULTS: Concerning tibial torsion, the TTA was an average of 36.7° (range, 17.2°-54.4°; SD, 8.78) When the syndesmotic cylinder was rotated to be parallel to the ground, the proximal fibula had nonlinear or linear overlap with the lateral border of the tibia, regardless of the joint morphology. In this non-overlapping view, three Weber's indices for normal fibular length could be better visualized than the mortise view. CONCLUSION: The syndesmotic cylinder in the proximal end of the incisura fibularis could be consistently placed parallel to the ground by internally rotating the tibia until there was a nonlinear or linear overlap between the proximal fibula and the tibia, regardless of the joint morphology.

Influence of unstable ankle fracture (type Weber C), osteosynthesis and syndesmotic transfixation on position of fibula in tibiofibular notch: a cadaveric study.

PURPOSE: The aim of the cadaveric study was to determine the effects of an unstable ankle fracture on the position of the fibula in the incisural notch and subsequently to evaluate the alterations resulting from the individual steps of a guideline-based osteosynthesis. METHODS: In a specimen model with 20 uninjured fresh-frozen lower legs with induced unstable fracture of the fibula (type Weber C), a guideline-based osteosynthesis was performed. The distances between the anterior and posterior edges of the tibia and fibula and in the center of the incisural notch, as well as the rotation angle of the fibula, were measured in the acquired 3D image data sets and were compared with the intact condition of the ankle mortise. RESULTS: The dissection of the syndesmosis and osteotomy of the fibula results in an external rotation the fibula by 3.6° (p = 0.000), while the distance between the anterior edge of the tibia and the fibula widens by 1.86 mm (p = 0.000). After osteosynthesis of the fibula and transfixation of the syndesmotic region using a positioning screw, the posterior distance is no longer substantially increased by 0.22 mm (p = 0.103) but also reduced by 0.1 mm (p = 0.104) in the tibiofibular notch. The external rotation of the fibula remains slightly increased by just 0.45° (p = 0.009). CONCLUSION: The results indicate that there is a tendency for over-compression when adjusting the tibiofibular distance and that the fibula in the tibiofibular notch tends to remain slightly rotated externally.