Distal Tibiofibular Syndesmosis Research Articles

Distal Tibiofibular Syndesmosis Injuries in the National Football League (NFL): A Spectrum of Pathology That Correlates With Time to Return to Full Participation.

Studies routinely evaluate high ankle sprains in isolation, but recent data suggest that these injuries are often associated with concomitant pathology, potentially influencing return to full participation. In National Football League (NFL) players, isolated high ankle sprains are rare and syndesmosis injuries with concomitant pathology will result in increased time to return to full participation. Cross-sectional study. Level 3. Distal tibiofibular syndesmosis injuries sustained by NFL players between 2017 and 2019 were identified through NFL Injury Surveillance Database queries and verified with video analysis. Each injury underwent a comprehensive magnetic resonance imaging (MRI) review. Regression modeling was utilized to explore the influence of numerous imaging findings on time to return to full participation. There were 83 external rotation ankle injuries involving the syndesmosis. Isolated distal tibiofibular syndesmosis injuries were rare (n = 11; 13%) and more often associated with other ligamentous injury (deltoid ligament and lateral ligamentous complex) and/or fractures. Regression modeling resulted in clustering of 3 injury pattern groups for time to return to full participation across numerous imaging findings: syndesmosis injury-fracture combinations (250 days [interquartile range [IQR,] 142-266 days]), syndesmosis injury with complete deep deltoid tear or acute diastasis (175 days [IQR, 20-248 days]), and all other syndesmosis injuries (27 days [IQR, 18-46 days]). In NFL athletes with external rotation ankle injuries, isolated distal tibiofibular syndesmosis injuries were rare and more often associated with concomitant pathology. Time to return to full participation was affected by an associated fracture and complete deep deltoid ligament tear or diastasis but no other relevant MRI variables such as lateral ligament complex involvement or the presence of osteochondral lesions or bone contusions.

Predictive Modeling for Functional Outcomes After All-Inside Arthroscopic Anterior Talofibular Ligament Repair of Chronic Ankle Instability.

Arthroscopic anterior talofibular ligament repair (AATFLR) is a surgical strategy to treat chronic ankle instability (CAI) patients. This study identified risk factors that influenced the functional outcomes of AATFLR for CAI and developed prognostic nomogram for predicting functional outcomes in future AATFLR cases. Patients undergoing AATFLR from January 2016 to June 2022 with at least 10 months of follow-up were included in the study. The Karlsson Ankle Functional Score (KAFS) was evaluated preoperatively and at last follow-up visit. A total of 15 potential predictors including age, sex, body mass index, side affected, time from injury to surgery, sports-related injury, osteophyte, loose bodies, distal tibiofibular syndesmosis, ATFL avulsion fracture, Outerbridge classification of osteochondral lesions, postoperative immobilization method, ambulation time, walking time, and follow-up time, were recorded. We first used univariate binary logistic regression analysis to select the potential significant prognostic features, which were then subjected to the least absolute shrinkage and selection operator (LASSO) regression algorithm for final feature selection. A nomogram based on the regression model was developed to estimate the functional outcomes of patients. Models were validated internally using bootstrapping and externally by calculating their performance on a validation cohort. Overall, 200 ankles fit inclusion criteria. Of these 200, a total of 185 (92.5%) ankles were eligible and divided into development (n = 121) and validation (n = 64) cohorts. Four predictors were ultimately included in the prognostic nomogram model: age, sex, sports-related injury, and postoperative immobilization method. We found in our cohort that the significant predictors of poorer functional outcomes of AATFLR were postoperative immobilization with lower-leg cast, female sex, non-sports-related ankle sprain, and increasing age. Prognostic nomograms were created. Level III, retrospective cohort study.

Effect of Distal Tibiofibular Destabilization and Syndesmosis Compression on the Flexibility Kinematics of the Ankle Bones: An In Vitro Human Cadaveric Model.

Overcompression of the distal tibiofibular syndesmosis during open reduction and internal fixation of ankle fracture may affect multidirectional flexibility of the ankle bones. Ten cadaveric lower limbs (78.3±13.0 years, 4 female, 6 male) underwent biomechanical testing in sagittal, coronal, and axial rotation with degrees of motion quantified. The intact force (100%) was the force needed to compress the syndesmosis just beyond the intact position, and overcompression was defined as 150% of the intact force. After intact testing, the anterior inferior tibiofibular ligament (AITFL), interosseus membrane (IOM), and posterior inferior tibiofibular ligament (PITFL) were sectioned and testing was repeated. The IOM and AITFL were reconstructed in sequence and tested at 100% and 150% compression. Overcompression of the syndesmosis did not significantly reduce ROM of the ankle bones for any loading modality (P > .05). IOM+AITFL reconstruction restored distal tibiofibular axial rotation to the intact condition. Axial rotation motion was significantly lower with AITFL fixation compared with IOM fixation alone (P < .05). The proximal tibiofibular syndesmosis demonstrated significantly higher motion in axial rotation with all distal reconstruction conditions. As assessed by direct visualization, overcompression of the distal tibiofibular syndesmosis did not reduce ROM of the ankle bones. Distal tibiofibular axial rotation was significantly lower with IOM+AITFL fixation compared with IOM augmentation alone. Distal tibiofibular axial rotation did not differ significantly from the intact condition after combined IOM+AITFL fixation. Dynamic fixation of the distal tibiofibular syndesmosis resulted in increased axial rotation at the proximal tibiofibular syndesmosis. These biomechanical data suggest that inadvertent overcompression of the distal tibiofibular syndesmosis when fixing ankle fractures does not restrict subsequent ankle bone ROM. The AITFL is an important stabilizer of the distal tibiofibular syndesmosis in external rotation. controlled laboratory study.

Equivalent Fracture Patterns Demonstrate Poorer Postoperative Functional Outcomes Among Pronation-External Rotation IV Ankle Fractures.

Pronation-external rotation IV (PER IV) ankle fractures are relatively uncommon among rotational ankle fractures, but they are the most severe type. Although recent studies have shown satisfactory functional recovery in PER IV after surgical treatment, the different outcomes between fracture patterns and equivalent fracture patterns have not yet been evaluated. This study aims to compare short-term outcomes in PER IV ankle injuries between fracture patterns and equivalent fracture patterns. This retrospective study was conducted at Quzhou Affiliated Hospital of Wenzhou Medical University, Quzhou, China, from July 2023 to October 2023. A total of 41 PER IV injuries from 2018 to 2022 were included and followed for at least one year. The American Orthopaedic Foot and Ankle Society (AOFAS) Ankle‑Hindfoot Scale, Ankle Range of Motions (ROM), and Visual Analogue Scale (VAS) for pain scores were the main outcome measures. The rate of postoperative complications was the secondary outcome measure. Patient demographics were compared in PER IV fractures and PER IV ankle equivalent fractures. The mean follow-up time was 18.2 ± 4.2 (range, 12-24) months. Postoperative X-ray and CT scans showed a satisfactory reduction of the ankle joint and syndesmosis. No reduction loss of distal tibiofibular syndesmosis or ankle joints was found at the 12-month follow-up. The average AOFAS scores after one year in both groups were satisfactory (fracture group vs. fracture equivalent group, 96.72 ± 4.21 vs. 92.63 ± 5.36; P < 0.05). The average VAS scores after one year in both groups were satisfactory (fracture group vs. fracture equivalent group, 1.45 ± 2.01 vs. 1.38 ± 1.96; P > 0.05). The average ROM scores after one year in both groups were satisfactory (dorsiflexion, fracture group vs. fracture equivalent group, 15.21 ± 5.62 vs. 13.46 ± 4.35; P > 0.05; plantar flexion, fracture group vs. fracture equivalent group, 38.62 ± 9.68 vs. 42.32 ± 5.28; P > 0.05). For patients with PER-IV ankle injuries, the fracture mode had a better prognosis than the fracture equivalent mode.

Standing on single foot-binding test yields satisfactory results as a novel method for the diagnosis of distal tibiofibular syndesmosis instability: a prospective, cross-sectional diagnostic-accuracy study

BackgroundNon-invasive diagnosis of distal tibiofibular syndesmosis instability (DTSI) was a great challenge to clinicians. We designed a new method, the Standing on single foot-Binding test, and investigated the accuracy of the test in the diagnosis of distal tibiofibular syndesmosis instability in adults with a history of ankle injury.Methods85 participants with ankle injury were subjected to the Standing on single foot-Binding test, MRI and palpation to detect the distal tibiofibular syndesmosis instability (DTSI) and the findings were compared with ankle arthroscopic results. Both participants and arthroscopist were blind to the predicted results of the clinical tests. Sensitivity, specificity, PPV, NPV, LR+, LR − and their 95% CIs were calculated for each of the clinical tests as well as for the positive clinical diagnosis.ResultsThe Standing on single foot-Binding test (SOSF-B test) outperformed MRI and palpation, in terms of sensitivity (87.5%/84.38%), specificity (86.79%/86.79%), PPV (80%/79.41%), NPV (92%/91.2%), LR+ (6.625/6.39), LR- (0.14/0.18) and diagnostic accuracy (87.06/85.88), among others, in the diagnosis of distal tibiofibular syndesmosis instability (DTSI). The diagnostic performance of 20° SOSF-B test was virtually identical to that of 0° SOSF-B test. According to the prevalence (28.7%) of DTSI and LR of four tests, the post-test probability could be used in clinical practice for the prediction of DTSI.ConclusionThis prospective and double-blind diagnostic test showed that the SOSF-B test is clinically feasible for the diagnosis of distal tibiofibular syndesmosis instability (DTSI), and new diagnostic tools for rapid screening of distal tibiofibular syndesmosis instability (DTSI).Level of evidenceII.

Ankle sprains: a review of mechanism, pathoanatomy and management

Ankle sprains are one of the most common musculoskeletal injuries. A sprain is defined as the stretching or tearing of ligaments; in the ankle these are the lateral ligamentous complex, deltoid ligament and distal tibiofibular syndesmosis ligaments. The mechanism of injury dictates which ligaments get injured, with the most common being inversion injuries causing anterior talofibular ligamentous sprain. Initial management of an ankle sprain consists of protection, rest, ice, compression and elevation. After the first 72 hours, the treatment depends on the severity of the sprain, with physiotherapy forming the mainstay of treatment in the majority of cases. In addition to strengthening exercises proprioceptive re-training helps with rehabilitation. The goal of treatment is to prevent chronic instability from occurring. Aside from syndesmotic injuries, surgical treatment is rarely required in the acute setting. Delayed ligamentous reconstruction may be required if chronic instability occurs, and is described as being an anatomic or non-anatomical reconstruction. This article reviews the anatomy, pathophysiology, clinical assessment and management of patients with ankle sprains.

Syndesmosis dislocation and ankle ligament stress in the posterior malleolus fracture fixated – “in vitro analysis”

PurposeThe objectives of this study were to compare syndesmosis dislocation and ankle ligament stress after the fixation of the posterior malleolus fracture (PMF) with four different techniques by Finite Element Analysis (FEM). MethodsFour internal fixation techniques used for fixation of PMF were assessed by FEM: posterior one-third tubular 3.5 mm buttress plate (PP) with one screw (PP 1 screw), PP with two screws (PP 2 screws), two cannulated 3.5 mm lag screws in the anteroposterior (AP) direction (AP lag screws), and two posteroanterior (PA) cannulated 3.5 mm lag screws (PA lag screws). PMF with 30% fragment size was simulated through computational processing reconstructed from computed tomography (CT). The simulated loads of 700 N and 1200 N were applied to the proximal tibial end. The FEM evaluated the syndesmosis dislocation (mm) and stress values of the posterior tibiofibular ligament (PTFL) (in Kpa) and deltoid ligament (in Kpa) in the four mentioned subgroups. ResultsWe found that with a load of 700 N, syndesmosis dislocation varied from 6.5 to 7.9 mm, being the lowest and greatest for PA lag screw and PP 1 screw, respectively. In all groups was observed a greater dislocation in the syndesmosis at 1200 N of load. We observed that the stress values on the PTFL were lower for AP lag screws and PP 2 screws with 700 N and 1200 N, respectively. For both loads, PP 1 screw presented the greatest stress. Regarding the stress in the deltoid ligament, the AP lag screws presented the lowest stress for 700 N and PP 1 screw for 1200 N. For all fixation techniques, the syndesmosis displacement and ligament stresses were higher when 1200 N were imposed. ConclusionThis study demonstrated that PMF fixed with lag screws presents greater stability in the distal tibiofibular syndesmosis and higher joint loadings promoted greater displacement and ligaments stress, regardless of the fixation technique. Besides, lower stress in the syndesmosis is accompanied by a greater load on the deltoid ligament.

Association of Periprosthetic Fibula Fracture With Knotless Suture Button (TightRope) Fixation for Ankle Syndesmosis in Elite Athletes

Background: Suture button fixation is frequently used to stabilize the distal tibiofibular syndesmosis in athletes sustaining an isolated ligamentous syndesmosis injury. Purpose: To report on a series of periprosthetic fibula fractures adjacent to the lateral suture button after a subsequent unrelated ankle injury or progressive stress injury after initial ankle syndesmosis stabilization using the knotless TightRope (Arthrex). Study Design: Case series; Level of evidence, 4. Methods: Eight elite athletes with periprosthetic fibula fractures and stress injuries around the lateral suture buttons were evaluated. In all athletes, the knotless TightRope had been used to stabilize an isolated ligamentous ankle syndesmotic injury, after which all patients recovered and returned to professional sports at their preinjury level. The athletes subsequently developed an acute fibula fracture or a fibula stress fracture related to the 3.7-mm drill hole in the fibula adjacent to the lateral suture buttons after a mean of 14.1 months (range, 5-29 months). The management of these complications was analyzed. Results: Five athletes sustained a periprosthetic fibula fracture in the form of undisplaced spiral Weber B injuries after a subsequent, unrelated injury. Poor healing response was noted with initial nonoperative treatment for the first 2 athletes, and surgical intervention was performed with successful union of the fracture and return to sports. The subsequent 3 athletes had early surgery with uneventful recovery. Another 3 athletes developed stress injuries adjacent to the fibula suture button without a history of acute trauma. In 2 of the 3 athletes, the position of lateral suture buttons was in the anterior third of the fibula. Initial nonoperative management yielded poor healing response, and subsequent surgical intervention was required to enable healing and return to sports. Conclusion: Nonoperative management of fractures adjacent to the fibula suture button of a knotless TightRope may lead to a delay in union. Therefore, early surgical intervention should be considered in elite athletes, whose return-to-sports time is critical. Care is needed to ensure that the fibula hole for the suture button is centrally located because the eccentric placement of the fibula hole in the anterior third of the fibula may contribute to the development of a stress reaction or stress fracture. Surgical intervention for a periprosthetic fibula stress fracture leads to satisfactory resolution of symptoms.

Normal Values for Distal Tibiofibular Syndesmotic Space With and Without Subject-Driven External Rotation Stress.

The diagnosis and treatment of distal tibiofibular syndesmosis (DTFS) injury can be challenging, especially in cases of subtle instability that may be masked on 2-dimensional conventional radiographs. Weightbearing computed tomography (WBCT) has recently emerged as a useful diagnostic tool allowing direct assessment of distal tibiofibular area widening. The purpose of the current study was to examine and report normal threshold values for DTFS area measurements in a cohort of healthy volunteers, assessing the ankles in natural weightbearing position and under subject-driven external rotation stress. In this prospective study, we enrolled 25 healthy volunteers without a history of DTFS injury or high ankle sprain, previous foot and ankle surgery, or current ankle pain. Subjects with any prior ankle injuries were excluded. Study participants underwent bilateral standing nonstress and external rotation stress WBCT scans. The DTFS area (mm2) was semiautomatically quantified on axial-plane WBCT images 1 cm proximal to the apex of the talar dome using validated software. Syndesmosis area values were compared between "unstressed" and "stressed" ankles, as well as left and right ankles. Statistical analysis was performed using independent t tests/Wilcoxon analysis with statistical significance defined as P <.05. The study cohort consisted of 50 ankles in 25 patients (12 males, 48%) with a mean age of 28.7 ± 9.3 years. In the unstressed ankle, the mean pooled DTFS area was determined to be 103.8 + 20.8 mm2. The mean syndesmosis area of unstressed left ankles (104.2 + 19.5 mm2) was similar to unstressed right ankles (109.2 + 17.2 mm2) in the cohort (P = .117). With external rotation stress, the DTFS area of left ankles (mean difference -0.304 mm2, CI -12.1 to 11.5; P = .082), right ankles (mean difference -5.5 mm2, CI 16.7-5.7; P = .132), and all ankles (mean difference -2.9 mm2, CI -10.8 to 5.1; P = .324) remained similar. This study presents normal values and range for DTFS area calculation. In uninjured ankles with expected intact ligaments, subject-driven external rotation stress did not result in significant widening of the DTFS space as imaged on with WBCT. Level II, cross-sectional study.

The distal tibiofibular syndesmosis is a reliable landmark for 3° varus tibial resection in total knee arthroplasty: a radiological evaluation on 1296 cases.

The purpose of this study was to evaluate the reproducibility and the accuracy of distal tibiofibular syndesmosis (DTFS) as landmark to perform controlled varus tibial resections during total knee arthroplasty (TKA). The hypothesis was that DTFS can be used to perform an accurate 3° varus tibial cut. A retrospective analysis on a consecutive series of standard weightbearing full-length anteroposterior views of the lower limbs radiographic images was conducted. For each radiograph, the hip-knee-ankle (HKA) angle, the angle between the tibial mechanical axis and the line connecting the centre of the tibial spines and the DTFS (tibiofibular angle, TFA) and the medial proximal tibial angle (MPTA) were calculated. Each measurement was carried out twice by three independent observers, and intra- and inter-observer measurement reliability were assessed using the intraclass correlation coefficient (ICC) analysis. A total of 1296 lower limbs were analysed from a series of 648 weightbearing full-length anteroposterior radiographs. The ICC were > 90% for all measurements. The mean TFA value was 2.94 ± 0.68 (range 2.38-3.51). No differences were detected comparing the mean TFA value on the right and left limb (p = 0.795) as well as comparing the values in male and female patients (p = 0.691). Linear regression analysis did not find statistically significant correlation between TFA and MPTA, or TFA and HKA angles, respectively. The distal tibiofibular syndesmosis is a reliable and easy reproducible radiographic landmark that can be used when planning a 3° varus tibial cut. Future studies are needed to confirm the validity of this method also in clinical settings. IV, retrospective case series.

Clinical study of a steel cable fixation for distal tibiofibular syndesmosis injury.

In order to overcome the shortcomings of common surgical fixation methods for Distal Tibiofibular Syndesmosis (DTS) injuries, which include the inability to exercise early, significant surgical trauma, and the risk of loosening and breakage of implants, we have designed and implemented a new technique using steel cable fixation to treat DTS injuries. Twenty-six patients treated with steel cable fixation for DTS injury between March 2013 and March 2019 in the Second Hospital of Tangshan City trauma department were followed up to monitor the efficacy of treatment. There were 16 males and 10 females between the ages of 19 and 64, with a mean age of 41.81 ± 9.54 years. All patients were examined by X-ray and CT for 3 days before and after surgery. The patients were then reexamined by X-ray 6 and 9 weeks postoperatively, and by CT 1 year later. The treatment results were evaluated by comparing the distal tibiofibular anterior, middle, and posterior gap changes and the Baird-Jackson score. The 26 patients attained good postoperative repositioning, with a fracture healing time of 2.5 to 3 months. and the Baird-Jackson score was 96 ± 2.78. After surgery, the DTS gaps observed in the CT scans taken 3 days and 1 year postoperatively in all patients were significantly reduced compared to the preoperative measurements, with statistical significance (P < .05). However, when comparing the CT scans taken 1 year postoperatively to those at 3 days postoperatively, there was no significant change in the anterior gap. The middle and posterior gaps of DTS showed a slight increase with statistical significance (P < .05), but all measurements remained within the normal range. Steel cable fixation for DTS injury has the advantages of reliable fixation, early functional exercise, and reduction in the number of operations, and no adverse effects or complications were found.

The Impact of 3D Foot Alignment on Detection of Distal Tibiofibular Syndesmotic Widening after Injury using Comparative Contralateral Distance Mapping

Category: Ankle; Trauma Introduction/ Purpose: Previous studies identified a link between increased hindfoot valgus and distal tibiofibular syndesmosis (DTFS) widening in patients with flatfoot deformity using foot-ankle offset (FAO). However, it is not known what the impact of 3D foot alignment is on the DTFS in the presence of a known syndesmotic injury, particularly in varus. Weight-bearing Computed Tomography (WBCT) has emerged as a highly precise tool for diagnosing deformities of the foot and ankle. Under weight-bearing, it is possible to precisely detect deviations in DTFS stability. The objective of this cadaveric study was to determine the relationship between hindfoot alignment, measured by FAO, and DTFS widening in specimens with complete DTFS ligamentous injury. We hypothesized that DTFS widening would be significantly greater in specimens with increased hindfoot valgus. Methods: Two WBCT scans of the foot and ankle were obtained for each of 17 matched pairs (34 legs) of through-knee cadaveric specimens in a radiolucent frame under 80lbs of load to simulate double legged stance, a baseline scan with intact syndesmotic ligaments and a second after surgical ligament sectioning. All syndesmotic ligaments were released through a direct lateral approach to the distal fibula. Models of the bones were created from scans using Disior Bonelogic. Distance mapping was used to evaluate DTFS widening over the entire DTFS interface, as well as the anterior/posterior sections, in the first 1cm, 3cm, and 5cm from the joint after injury. Post-injury distance maps were compared to the contralateral baseline normal scan as a control. FAO was measured post-injury and compared to the difference in DFTS widening between the injured leg and its contralateral, healthy control. Linear regression and Spearman’s correlations were used to evaluate relationships. Results: Significant correlations between hindfoot alignment and DTFS widening were identified at every level in the syndesmosis. The Spearman’s rho values for the entire DTFS interface at 1cm, 3cm, and 5cm were 0.393 (p = 0.0316), 0.458 (p = 0.0101), and 0.369 (p = 0.0446), respectively. Anterior Spearman’s rho values at 1cm and 3cm were 0.453 (p = 0.0119) and 0.420 (p = 0.0209), respectively. Inter-observer variability of the FAO measurements showed no statistical difference (p = 0.4248). Extremely varus FAO measurements (FAO &lt; -10%) showed negligible changes in syndesmotic opening. Linear regression also demonstrates a positive trend. The R2 values for the entire interface at 1cm, 3cm, and 5cm were 0.127, 0.213, and 0.158. Anterior R2 values at 1cm and 1cm were 0.133 and 0.1583. Conclusion: In this cadaveric study, we confirmed our hypothesis showing that valgus FAO was correlated with syndesmosis opening from an uninjured to an injured site. These data are in accord with prior findings relating FAO and DTFS opening in flatfeet and additionally demonstrate a stronger positive trend in the presence of known injury with smaller changes in tibiofibular distances after injury for extreme varus alignments. This study provides important context to the clinically relevant comparison of contralateral feet. The trend in our data allows for predictable results for the degree of injury in patients with valgus foot alignment.

Suture-Button versus Syndesmotic Screw in the Treatment of Distal Tibiofibular Syndesmosis Injury

Suture-Button versus Syndesmotic Screw in the Treatment of Distal Tibiofibular Syndesmosis Injury

Effect of Distal Tibiofibular Syndesmosis Overcompression on the Biomechanical Properties of the Ankle Bones: An In Vitro Cadaveric Model

Category: Trauma; Ankle Introduction/Purpose: Overtightening of the distal tibiofibular syndesmosis during open reduction and internal fixation (ORIF) of ankle fractures remains a clinical concern, and there are limited data delineating the effect of syndesmosis overcompression on subsequent range of motion of the ankle joint bones. The primary objective of the current study was to determine the effect of syndesmotic overcompression on the relative range of motion (ROM) of the tibia, fibula, and talus, and to determine the syndesmotic fixation construct that most accurately restores native motion. Methods: Ten cadaveric lower limbs were utilized (78.3±13.0 yrs, 4F; 6M). A musculoskeletal simulator at ±7.5 Nm was used to test flexibility in dorsiflexion-plantarflexion, inversion-eversion, and internal-external rotation. After intact testing, syndesmotic probes were used to arthroscopically measure the intact position of the distal tibiofibular syndesmosis. The force needed to compress the syndesmosis just beyond the intact position represented the intact force (100%), and overcompression was defined as 150% of the intact force. The anterior inferior tibiofibular ligament (AITFL), interosseus membrane (IOM), and posterior inferior tibiofibular ligament (PITFL) were then sectioned. Testing was repeated for destabilized, IOM reconstruction at 100% compression and 150% overcompression, IOM reconstruction plus AITFL fixation at 100% compression and 150% overcompression, and AITFL fixation alone. ROM data was reported as a percentage of the intact condition. Repeated measures ANOVA and Bonferroni post hoc test were performed to assess differences between conditions with p&lt; 0.05. Results: Average force needed to compress the syndesmosis was 71.0 ± 22.2 N. There was a significant increase in distal tibiofibular ROM in internal and external rotation for all conditions compared to intact (Figure 1) (p &lt; 0.05). In the axial plane, reconstruction of the IOM membrane did not restore the intact condition and was similar to the destabilized treatment, regardless of compression force. The addition of AITFL fixation significantly reduced distal tibiofibular motion compared to IOM reconstructions alone, but still did not approach the intact condition. Overcompression of the syndesmosis did not significantly affect relative ROM of the ankle bones in any plane (p&gt;0.05). Changes in the proximal tibiofibular ROM were similar in magnitude and direction as the distal tibiofibular ROM for all conditions. Conclusion: In the current study, overcompression of the distal tibiofibular syndesmosis did not restrict relative ROM of the tibia, fibula, or talus. Reconstructing the AITFL in addition to the IOM decreased tibiofibular ROM, particularly in the axial plane. In the clinical setting, surgical reconstruction with dynamic fixation of the distal tibiofibular syndesmosis may result in increased ROM and mechanical stress at the proximal tibiofibular articulation.

Ins and Outs of the Ankle Syndesmosis from a 2D to 3D CT Perspective

Despite various proposed measurement techniques for assessing syndesmosis integrity, a standardized protocol is lacking, and the existing literature reports inconsistent findings regarding normal and abnormal relationships between the fibula and tibia at the distal level. Therefore, this study aims to present an overview of two- (2D) and three-dimensional (3D) measurement methods utilized to evaluate syndesmosis integrity. A topical literature review was conducted, including studies employing 2D or 3D measurement techniques to quantify distal tibiofibular syndesmosis alignment on computed tomography (CT) or weight-bearing CT (WBCT) scans. A total of 49 eligible articles were included in this review. While most interclass correlation (ICC) values indicate favorable reliability, certain measurements involving multiple steps exhibited lower ICC values, potentially due to the learning curve associated with their implementation. Inconclusive results were obtained regarding the influence of age, sex, and height on syndesmotic measurements. No significant difference was observed between bilateral ankles, permitting the use of the opposite side as an internal control for comparison. There is a notable range of normal and pathological values, as evidenced by the standard deviation associated with each measurement. This review highlights the absence of a consensus on syndesmotic measurements for assessing integrity despite numerous CT scan studies. The diverse measurement techniques, complexity, and inconclusive findings present challenges in distinguishing between normal and pathological values in routine clinical practice. Promising advancements in novel 3D techniques offer potential for automated measurements and reduction of observer inaccuracies, but further validation is needed.

TightRope elastic fixation combined with functional total repair of inferior tibiofibular ligament in treatment of distal tibiofibular syndesmosis injury

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. 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. 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). 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.

Association between the distal tibiofibular syndesmosis morphology classification and ankle osteoarthritis: a retrospective study

BackgroundSyndesmosis injury is proposed to contribute to ankle stability and osteoarthritis (OA). However, whether distal tibiofibular syndesmosis structure is closely related to ankle OA is unclear. We hypothesized that different DTS morphology classifications would affect the biomechanics properties in ankle OA. The study aimed to determine the association between the distal tibiofibular syndesmosis (DTS) morphological classification and ankle OA.MethodsThis is a retrospective study examining imaging data of 147 patients (87 males and 60 females) with ankle OA. Magnetic resonance imaging was used to access the DTS morphological classification, according to measuring various parameters. Joint space narrowing and osteophytes were measured using ankle weight-bearing radiography. The classification and parameters were analyzed to determine the relationship between the syndesmosis classification and the abnormality of ankle OA.ResultsFive morphological classifications of the DTS, including Chevron (19.6%), Widow’s peak (16.2%), Flat (22.3%), Trapezoid (32.0%), and Crescent (19.6%), were shown. There were statistical differences between DTS classification and tibial angle surface angle (TAS) (P = .009) and talar tilt angle (TTA) (P = .014). The TAS (degree) of the Crescent (86.47 ± 3.21) was less than Chevron (88.75 ± 2.72) (P = .006), Widow’s peak (89.26 ± 3.15) (P = .001), Flat (88.83 ± 3.62) (P = .003) and Trapezoid (88.11 ± 2.62) (P = .041), respectively. The TTA (degree) of Crescent (86.83 ± 5.30) was less than Chevron (89.28 ± 2.46) and Widow’s peak (89.82 ± 3.41). The men were greater than women for TAS (P = .008) and angle (P = .003), which are consistent with osteophyte (P = .019) and the modified Kellgren–Lawrence grades (P = .041) between gender.ConclusionsDTS morphological classification might affect the biomechanics properties in TAS and TTA in ankle OA. In clinical practice, surgeons should pay attention to the effects of DTS on ankle OA.Level of Evidence: Level III, retrospective study.

The distal tibiofibular joint effusion may be a reliable index for diagnosing the distal tibiofibular syndesmosis instability in ankle

PurposeTo analyze the accuracy of MRI in diagnosis of distal tibiofibular syndesmosis instability (DTSI) and construct new diagnostic parameters.Materials and methodsThis retrospective study evaluated 212 patients with history of ankle sprains and 3 T MRI and received a final diagnosis of distal tibiofibular syndesmosis instability by ankle arthroscopic surgery from October 2017 and December 2021. We compared the accuracy of syndesmotic injury, qualitative index of distal tibiofibular joint effusion (DTJE), and quantitative index of distal tibiofibular joint effusion (DTJE) in diagnosing distal tibiofibular syndesmosis instability. The criteria for syndesmotic injury were consistent with previous literature, and DTJE was grouped according to the pre-experimental results.ResultsA total of 212 patients (mean age, 35.64 ± 11.79, 74 female and 138 male) were included. Independent predictive MRI features included syndesmotic injury, qualitative index of distal tibiofibular joint effusion, and quantitative index of DTJE including the height, projected area of equal-point method, and projected area of incremental-value method. The quantitative index of DTJE showed a higher area under the receiver operating characteristic curve (0.805/0.803/0.804/0.811/0.817/0.805 > 0.8, P < 0.05; in comparison with all other method). The height measurement method was simpler and easier to operate, that could be gotten only by measuring the DTJE distance of a MRI independent layer, and the cut-off value of the effusion height was 8.00 mm and the Youden index (0.56) was the best.ConclusionsOur research translated a complicated string of MRI multi-dimensional spatial measurements into a simple measuring process, and established the significance of quantifying DTJE in the diagnosis of DTSI. We found that the 8-mm height of DTJE was a more specific indicator for DTSI and could serve as a novel MRI diagnostic cutoff in clinical practice.

Radiological Evaluation of Distal Tibiofibular Joint Anatomy Variations in Patients with and Without Syndesmotic Injury.

Syndesmosis injuries are a common and debilitating problem affecting the ankle joint, but the precise causes of these injuries remain unclear. In the current retrospective study, it was aimed to investigate the relationship between variations in the distal tibiofibular syndesmosis and surgically proven syndesmosis injuries. A total of 57 patients with surgically proven syndesmosis injuries and 51 patients without syndesmosis injuries were included as the control group. Computed tomography (CT) scans were used to measure six anatomical features 1cm proximal to the tibiotalar joint, including the anterior facet length (a), posterior facet length (b), angle between the anterior and posterior facets (c), fibular incisura depth (d), tibia thickness (e), and fibula thickness (f). Comparing the measurements of the patients with and without syndesmosis injury, it was demonstrated that the anterior facet length (a) (p = 0.022) was shorter and the a-b difference (anterior facet length-posterior facet length difference) (p = 0.010) tended toward negative values. Pearson correlation analysis demonstrated that a (r = -0.211, p < 0.033) and a-b (r = -0.254, p = 0.010) measurements were strongly negatively correlated with syndesmosis injury. Our study findings suggest that the shortness of the anterior facet and the difference in length are related to syndesmosis injuries. To the best of our knowledge, this is the first study to report this relationship with syndesmosis. This study sheds light on the underlying mechanisms of syndesmosis injury, which could help clinicians in the diagnosis, treatment, and prevention of this common ankle injury.Level of evidence: Level 4: case-control study.

Beyond the Malleoli: Part 2—Avulsion Fractures of the Hindfoot

Avulsion fractures of the ankle and hindfoot are a diverse group of injuries occurring at level of retinacular, capsuloligamentous, and tendinous attachments. Accurate identification of avulsion fractures and their origins is based on understanding the relevant soft-tissue anatomy. In the first part of this two-series article, avulsion fractures at level of the ankle retinacula and distal tibiofibular syndesmosis were reviewed. The second part of this series of two articles is dedicated to reviewing the relevant anatomy, injury mechanisms, classification, nomenclature, imaging, treatment, and complications of hindfoot avulsion fractures occurring at level of the lateral ankle ligament complex (distally), posterior talar process, tendinous attachments, and miscellaneous soft-tissue attachments not otherwise specified.