Ankle syndesmosis injuries: anatomy, biomechanics, mechanism of injury, and clinical guidelines for diagnosis and intervention

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.

Comparative Study for Surgical Treatment of Acute Distal Tibiofibular Syndesmotic Lesions Using the Modified Suture-Button Fixation Versus Static Syndesmotic Screw Fixation

INTRODUCTION

Several techniques to treat acute distal tibiofibular instability are described consisting in static and dynamic fixation procedures. The aim of our work is to compare the outcomes of acute syndesmotic injury fixation between the modified technique of dynamic fixation using the suture-button principle as an efficient and low-cost method and the classic static fixation.

METHODS

It is a prospective study including patients presenting with acute syndesmotic injury. After fracture fixation, residual syndesmotic instability was managed using syndesmotic screw in group A and dynamic fixation with a double Ethibond suture in group B. Functional results were assessed using the American Orthopaedic Foot and Ankle Society score (AOFAS) score. Radiological evaluation was done by a postoperative computed tomography (CT) scan of both ankles and plain X-rays of the ankle after surgery and at 18 months.

RESULTS

Group A included 20 patients meanwhile 35 patients were in group B. The reduction was satisfactory in the 2 groups according to the postoperative CT scan measurements. The mean healing time in group A was 49.65 days and 51.49 days in group B (P = .45). We did not find any significant difference in terms of loss of reduction in the 2 groups. The return to work was faster in group B (P = .04). Patients in group B had better AOFAS score (P = .03) and ankle range of motion than those in group A. The difference was statistically significant (P = .02 for dorsal flexion and P = .001 for plantar flexion). For group A, we did not note any early complications. Meanwhile, 7 patients developed skin complications in group B (P = .03). However, no significant difference was found in terms of late complications.

CONCLUSIONS

The modified dynamic suture-button fixation remains a therapeutic alternative in low-income countries that could achieve better outcomes than static fixation, with easy postoperative follow-up.

LEVELS OF EVIDENCE

Level II.

Deltoid ligament injuries: A review of the anatomy, diagnosis and treatments

PURPOSE

Ankle sprains remain the most common soft tissue injury presenting to Emergency Departments. Recently, there has been increased awareness and reporting of deltoid ligament injuries in association with injuries to the lateral ligament complex as well as with fibula fractures. This article reviews the currently available literature on the anatomy of the deltoid ligament, clinical and radiological diagnosis of injuries to the deltoid ligament and treatment recommendations.

METHODS

A literature review was conducted for keywords associated with deltoid ligament injuries. MEDLINE, PubMed and Embase databases were utilised for this search. Articles were included if involving an adult population, were English-language, were related to deltoid ligament injuries (with or without associated injuries) and reported on patho-anatomy, clinical or radiological diagnosis or treatment methods.

RESULTS

A total of 93 articles were assessed for relevance from the database search, and 47 were included after the removal of irrelevant articles and duplicates. Several studies reported on the clinical findings of deltoid ligament injury, as well as the radiographic analysis. Arthroscopy was considered the gold standard of diagnosis, with authors reporting on the potential benefit of performing arthroscopic repair or reconstruction at the same time. There were no studies that provided a system for the classification of deltoid ligament injury or larger studies of treatment pathways. Long-term studies of the incidence of instability in deltoid ligament injuries were not available.

CONCLUSION

There is limited evidence available regarding deltoid ligament injuries, particularly in terms of treatment options, either in isolation or with concomitant injuries. Long-term follow-up studies are needed to obtain more accurate data on the number of complications.

LEVEL OF EVIDENCE

Level IV.

Patterns of ankle injury in soccer: MRI clues to traumatic mechanism

Understanding the traumatic mechanisms of ankle injuries in soccer is crucial for an accurate and complete MRI diagnosis. Many ankle injuries share universal mechanisms seen in other athletic activities, but certain patterns are found to be more specific and relatively unique to soccer. Ankle impingement syndromes encountered in soccer encompass a spectrum of disorders that include anterior and posterior impingement categories, with anterior impingement representing pathology relatively specific to soccer. Lateral ligamentous sprains are one of the most common injuries; however, there is a higher rate of injuries to the medial structures in soccer as compared to other sports. Ankle fractures are uncommon in soccer while bone contusions and chondral and osteochondral injuries frequently accompany ligamentous sprains. Tendon abnormalities in soccer most commonly result from overuse injuries and typically affect peroneal tendons, posterior and anterior tibialis tendons, and Achilles tendon. Acute Achilles tendon ruptures occur in both recreational players and elite soccer athletes. Tibialis anterior friction syndrome may mimic tibial stress fractures. Long-term sequelae of acute traumatic and chronic overuse ankle injuries in professional soccer players manifest as ankle osteoarthritis that is more prevalent compared to not only the general population, but also to former elite athletes from other sports. This article examines the most common and specific injuries in soccer in order of their frequency.

Current concepts in ankle fractures

Ankle fractures are among the most common orthopaedic injuries. Operative management is performed in unstable ankle fracture patterns to restore the stability and native kinematics of the ankle mortise and minimize the risk of post-traumatic degenerative changes. In this study, we review current concepts in ankle fracture management, including posterior malleolus fixation, syndesmosis fixation, deltoid ligament repair, fibular nailing, and early weightbearing, from both a biomechanical and clinical perspective.

Do lateral ankle ligaments contribute to syndesmotic stability: a finite element analysis study

Whether the lateral ankle ligaments contribute to syndesmotic stability is still controversial and has been the subject of frequent research recently. In our study, we tried to elucidate this situation using the finite element analysis method. Intact model and thirteen different injury models were created to simulate injuries of the lateral ankle ligaments (ATFL, CFL, PTFL), injuries of the syndesmotic ligaments (AITFL, IOL, PITFL) and their combined injuries. The models were compared in terms of LFT, PFT and EFR. It was observed that 0.537 mm LFT, 0.626 mm PFT and 1.25° EFR occurred in the intact model (M#1), 0.539 mm LFT, 0.761 mm PFT and 2.31° EFR occurred in the isolated ATFL injury (M#2), 0.547 mm LFT, 0.791 mm PFT and 2.50° EFR occurred in the isolated AITFL injury (M#8). The LFT, PFT and EFR amounts were higher in the both M#2 and M#8 compared to the M#1. LFT, PFT and EFR amounts in M#2 and M#8 were found to be extremely close. In terms of LFT and PFT, when we compare models with (LFT: 0.650 mm, PFT: 1.104) and without (LFT: 0.457 mm, PFT: 1.150) IOL injury, it is seen that the amount of LFT increases and the amount of PFT decreases with IOL injury. We also observed that injuries to the CFL, PTFL and PITFL did not cause significant changes in fibular translations and PFT and EFR values show an almost linear correlation. Our results suggest that ATFL injury plays a crucial role in syndesmotic stability.

Ankle syndesmotic reconstruction in chronic ankle syndesmotic injury

Acute syndesmotic injury is a common problem treated with different surgical tools. If not managed appropriately, it can lead to chronic ankle syndesmotic insufficiency. Chronic syndesmotic insufficiency is challenging to diagnose, and the patient can suffer for a long time. There is no consensus in previous literature on the surgical treatment of chronic syndesmotic injury. We present a case of personnel who suffered from chronic syndesmotic injury treated by syndesmotic reconstruction 5 years after his ankle fracture dislocation and returned to his work. This case highlights the importance of a CT scan post-reduction of an acute syndesmotic injury to assess accurate reduction, especially in severe injuries with frank diastasis.

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.

Team Approach: Perioperative Management of Pilon Fractures

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Tibial pilon fractures are devastating injuries requiring complexsurgical management resulting in a challenging postoperativecourse.

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A multidisciplinary approach is required to manage these injuries in addition to patients' medical comorbidities and concomitant injuries to achieve optimal outcomes.

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The case presented here demonstrates the importance of communication and teamwork between specialties in the management of a patient with a tibial pilon fracture that was medically optimized for surgery using a team-based approach.

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.

Diagnostic Value of DECT-Based Collagen Mapping for Assessing the Distal Tibiofibular Syndesmosis in Patients with Acute Trauma

Background: Injury to the distal tibiofibular syndesmosis (DTFS) is common in patients with trauma to the ankle, but diagnostic accuracy of conventional X-ray and CT is insufficient. A novel dual energy CT (DECT) post-processing algorithm enables color-coded mapping of collagenous structures, which can be utilized to assess the integrity of the DTFS. Methods: Patients were included in this retrospective study if they underwent third-generation dual-source DECT followed by 3T-MRI or ankle joint surgery within 14 days between January 2016 and December 2021. Three radiologists blinded to all patient data independently evaluated grayscale images and, after 8 weeks, grayscale and collagen mapping images for the presence of ligamentous injury or avulsion fractures of the DTFS. MRI and surgery provided the reference standard. Diagnostic accuracy parameters were calculated for all ratings, and a comparison of ROC curve analysis was performed to evaluate the incremental diagnostic value of color-coded images over grayscale images. Results: A total of 49 patients (median age 49 years; 32 males) were evaluated. Application of collagen mapping significantly increased sensitivity (25/30 [83%] vs. 20/30 [67%]), specificity (110/118 [93%] vs. 70/118 [60%]), positive predictive value (25/33 [76%] vs. 20/67 [30%]), negative predictive value (110/115 [96%] vs. 70/80 [88%]), and accuracy (134/147 [91%] vs. 90/147 [61%]) for the detection of injury to the DTFS (all parameters, p < 0.001). Collagen mapping achieved higher diagnostic confidence, image quality, and noise scores compared to grayscale CT (all parameters, p < 0.001). Conclusions: Collagen mapping yields substantially higher diagnostic accuracy and confidence for assessing the integrity of the distal tibiofibular syndesmosis compared to grayscale CT in patients with acute trauma. The application of this algorithm can accelerate the adequate diagnosis and treatment of DTFS injury in clinical routine.

Biomechanical Analysis of Tibiofibular Syndesmosis Injury Fixation Methods: A Finite Element Analysis

The optimal treatment strategy after syndesmotic injuries is still controversial. In our study, we aimed to evaluate ideal fixation method in syndesmotic injury by using finite element analysis method. A 3D SolidWorks model file was created by taking computed tomography (CT) images of the area from the right foot base to the knee joint level of a healthy adult male. The intact model, injury model, and 8 different fixation models were created that 3.5 mm screw and suture-button were used in. The models were compared in terms of lateral fibular translation, posterior fibular translation and external rotation of fibula compared to tibia and stress values occurred on screws and suture-buttons. In the hybrid-1 model, lateral fibular translation and external fibular rotation values were obtained as close to the intact model. Von Mises stresses occurred in the screw (435.7 MPa) and suture-button (424.7 MPa) that used in hybrid-1 model was more than single screw at 4 cm model (316.8 MPa) and single suture-button at 2 cm model (160.7 MPa). In the Hybrid-1 model, the screw compensates for posterior fibular translation and external fibular rotation, while the suture-button compensates for lateral fibular translation. Also, the effect of the distal suture-button preventing diastasis in case of proximal screw failure, it was concluded that the hybrid-1 model can be used as a good treatment alternative in the surgical treatment of distal tibiofibular syndesmotic injuries.

3D Mapping of the Lateral Malleolus Fractures for Predicting Syndesmotic Injuries in Supination External Rotation Type Ankle Fractures

Supination external rotation (SER) type ankle fracture is the most common ankle fracture in the Lauge-Hansen classification and is often accompanied with syndesmotic injury. However, the mechanism of this injury is indistinct and a suggestive role can be given by preoperative imaging. This study was to preoperatively predict whether SER type ankle fractures are accompanied with syndesmotic injuries by the means of lateral malleolus fracture mapping. One hundred and forty-eight patients diagnosed with SER type ankle fractures were retrospectively enrolled in this study. The baseline data were collected and computed tomography data were reconstructed in 3-dimensional (3D) model. Patients were divided into stable and unstable groups according to intraoperative Cotton test and whether the inferior tibiofibular screw was placed. All fracture lines were superimposed on the ankle template to create a fracture map, and the data on the fracture map were further measured. Logistic regression was conducted to identify relevant factors and the cutoff values were given using receiver operating characteristic curves. Forty-one patients were enrolled in the unstable group and 107 patients were enrolled in the stable group. The lateral malleolus fracture lines of the unstable group were higher and steeper than that in the stable group on lateral and posterior views. The fracture height of the posterior cortex and peak height were the significant contributing factors, and the cut-off values of posterior cortex, peak height and inclination angle were 40.35 mm (sensitivity: 78%, specificity: 82%), 55.34 mm (sensitivity: 85%, specificity: 70%) and 55.6° (sensitivity: 66%, specificity: 86%), respectively. In general, when the fracture lines of the lateral malleolus were high and steep, it was usually indicative of a syndesmotic injury and can be predicted by the preoperative 3D reconstruction of fracture height of posterior cortex, peak height and inclination angle. If the cut-off values of these indicators are exceeded, the syndesmotic injuries may be presented and need to be verified in the intraoperative Cotton test to decide whether to insert an inferior tibiofibular screw.

Can Weightbearing Cone-beam CT Reliably Differentiate Between Stable and Unstable Syndesmotic Ankle Injuries? A Systematic Review and Meta-analysis

BACKGROUND

Ankle injuries are common presentations to the emergency department and may lead to syndesmotic instability. These have a high socioeconomic burden due to prolonged rehabilitation, chronic pain, and posttraumatic arthritis. Early diagnosis is essential to minimize these complications, and the assessment of instability in the clinical setting is often limited by pain and clinician experience. Cross-sectional imaging of the distal syndesmosis accurately evaluates the syndesmosis through abnormal bony relationships, which in the presence of instability, worsens during physiological loading. Cone-beam CT (CBCT) has gained popularity in the diagnosis of these injuries because it enables syndesmotic assessment under weightbearing conditions, it mitigates the high radiation dose, and it is time-efficient.

QUESTIONS/PURPOSES

The purposes of this systematic review were: (1) to establish normal values for weightbearing CBCT of the syndesmosis in uninjured ankles and ascertain interobserver reliability and (2) to identify the impact of weightbearing on the syndesmosis in patients with occult ankle injuries and assess the effect of patient demographics on these metrics.

METHODS

This systematic review was reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and registered in PROSPERO (ID CRD42021248623). MEDLINE, PubMed, Embase, and Emcare databases were searched for studies assessing for syndesmotic instability, of which 307 studies were screened and 11 studies with 559 ankles in 408 uninjured patients and 151 patients with syndesmotic instability were included. All patients 18 years of age or older presenting with unilateral ankle injuries who underwent weightbearing CBCT for the diagnosis of an occult fracture or syndesmotic instability compared with the uninjured contralateral side were included. A control group of uninjured ankles was identified during weightbearing CBCT performed for other indications such as forefoot or midfoot injuries. Methodological assessment of the studies was performed using the Risk of Bias In Non-randomized Studies (ROBINS-1) tool and most included studies had a low risk of bias. Thus, a random-effects restricted maximum likelihood ratio model was used.

RESULTS

In the uninjured ankle, the mean area of the tibiofibular syndesmosis was 112.5 ± 7.1 mm 2 , which increased to 157.5 ± 9.6 mm 2 after injury when compared with uninjured ankles with a standardized mean difference of 29.5 (95% confidence interval 19.5 to 39.5; p < 0.01), and an excellent interobserver agreement (κ = 1.0 [95% CI 0.9 to 1.0]). However, syndesmosis volume decreased with age (β = -0.76; p = 0.04), and therefore, has a negative association with increasing age.

CONCLUSION

Our study has shown that the syndesmotic area is the most reliable parameter in the assessment of syndesmotic injuries because it increases in the presence of instability during weightbearing status. It is a composite measurement that could potentially allow clinicians to use weightbearing CBCT as an adjunct when there is a clinical suspicion of syndesmotic instability. Thus, weightbearing CBCT has the potential of being diagnostic of syndesmotic instability and should be evaluated against current radiological modalities to evaluate its accuracy.

LEVEL OF EVIDENCE

Level IV, prognostic study.

Incidence of (Osteo)Chondral Lesions of the Ankle in Isolated Syndesmotic Injuries: A Systematic Review and Meta-Analysis

OBJECTIVE

To determine and compare the incidence rate of (osteo)chondral lesions of the ankle in patients with acute and chronic isolated syndesmotic injuries.

DESIGN

A literature search was conducted in the PubMed (MEDLINE) and EMBASE (Ovid) databases from 2000 to September 2021. Two authors independently screened the search results, and risk of bias was assessed using the MINORS (Methodological Index for Non-Randomized Studies) criteria. Studies on acute and chronic isolated syndesmotic injuries with pre-operative or intra-operative imaging were included. The primary outcome was the incidence rate with corresponding 95% confidence intervals (CIs) of (osteo)chondral lesions of the ankle in combined and separate groups of acute and chronic syndesmotic injuries. Secondary outcomes were anatomic distribution and mean size of the (osteo)chondral lesions.

RESULTS

Nine articles (402 syndesmotic injuries) were included in the final analysis. Overall (osteo)chondral lesion incidence was 20.7% (95% CI: 13.7%-29.9%). This rate was 22.0% (95% CI: 17.1-27.7) and 24.1% (95% CI: 15.6-35.2) for acute and chronic syndesmotic injuries, respectively. In the combined acute and chronic syndesmotic injury group, 95.4% of the lesions were located on the talar dome and 4.5% of the lesions were located on the distal tibia. (Osteo)chondral lesion size was not reported in any of the studies.

CONCLUSIONS

This meta-analysis shows that (osteo)chondral lesions of the ankle are present in 21% of the patients with isolated syndesmotic injuries. No difference in incidence rate was found between the different syndesmotic injury types and it can be concluded that the majority of lesions are located on the talar dome.

PROSPERO REGISTRATION NUMBER

CRD42020176641.

Elastic Reconstruction of Chronic Instability of the Distal Tibiofibular Joint in an Obese Patient: A Case Report

An active, obese young patient was admitted to our clinic complaining of chronic ankle pain after fixation of his lateral malleolus fracture. His symptoms consisted of intermittent pain after prolonged walking, swelling, and feeling of instability. His clinical and radiological evaluations indicated chronic mechanical instability of his distal tibiofibular syndesmosis that remained unresponsive to conservative treatment.

Considering his age and activity level, we proceeded to a global syndesmotic reconstruction of the three major syndesmotic ligaments with split-thickness peroneus longus graft. According to this technique, the graft was passed through specific tibiofibular tunnels restoring the native stability and elasticity of the region.

The patient had an optimal postoperative function, with diminished symptoms and increased clinical scores. His late radiological evaluation revealed an anatomic ankle reduction with restoring his normal syndesmotic anatomy compared to his contralateral limb. Regardless of his high BMI, we noticed no further subluxation of his talus, while his general symptomatology was unremarkable at the 12-month follow-up.

In conclusion, elastic reconstruction of the distal tibiofibular joint with split-thickness peroneus longus graft provides excellent results at 12 months regardless of the patient’s BMI. To our knowledge, this is the only technique that restores the three main regional ligaments, simultaneously allowing for close-to-normal biomechanics and providing excellent short-term clinical outcomes.

Application of an arched, Ni-Ti shape-memory connector in repairing distal tibiofibular syndesmosis ligament injury

Objective

To investigate the clinical effect of internal fixation of a Ni–Ti arched shape-memory connector in the treatment of distal tibiofibular syndesmosis ligament injury.

Methods

From January 2013 to January 2016, 108 cases of ankle fracture with distal tibiofibular syndesmosis ligament injury in our hospital were selected, and all of them were fixed with ASCs or screw fixation. The functional evaluation and efficacy evaluation were performed according to the Olerud Molander Ankle Score (Omas) and SF-36. At the same time, follow-ups recorded the incidence of postoperative complications: osteoarthritis, superficial infection, symptomatic hard and soft tissue irritation, early removal and poor reduction of internal fixation, and later loss of reduction.

Results

In the ASC(Ni–Ti Arched shape-memory Connector) group, the incidence of symptomatic hardware, soft tissue or superficial infection decreased to 2.77%(from 13.8% or 11.1% in SCREW group). The early removal rate(2.77%) of internal fixation was also lower than that of the screw group. While the incidence of osteoarthritis is 13.8% in SCREW group, the incidence of osteoarthritis in the later follow-up was also as low as 1.38% in ASC group. Loss of fracture reduction due to removal of the fixation device for the distal tibiofibular syndesmosis ligament was not observed in the ASC group. With two postoperative scoring systems (OMAS and SF-36), patients in the ASC group significantly get higher score than that in SCREW group.

Conclusion

The design of the Ni–Ti arched shape-memory connector can be adapted to the irregular anatomical structure of the malleolus and the ability to continue to contract by body temperature. The use of ASCs in fixation of articular ligaments can preserve a slight range of motion, and the results suggest that ASCs can effectively reduce the incidence of fixation looseness, fracture, infection and other complications.

Kinematic Tibiofibular Syndesmotic Measurements as Indicators of Tibiotalar Osteoarthritis: Exploratory Analysis Using 4-Dimensional Computed Tomography

OBJECTIVE

The aim of this study was to evaluate the association between 4-dimensional computed tomography (4DCT)-derived measurements of tibiofibular syndesmosis during active dorsiflexion-plantarflexion motion and the presence of tibiotalar osteoarthritis (OA).

METHODS

Sixteen ankle joints underwent 4DCT imaging during active dorsiflexion-plantarflexion. Syndesmotic anterior distance (SAD) and syndesmotic translation (ST) were obtained by a foot-and-ankle surgeon. We used Kellgren-Lawrence (KL) grading to determine tibiotalar OA.

RESULTS

Of 16 scanned ankles, 12 ankles had KL ≥2 at the tibiotalar joint. In these ankles, SAD (-0.4, P = 0.02) and ST (-0.9, P = 0.006) measurements significantly changed during the dorsiflexion-plantarflexion motion. Changes in SAD measurements were significantly correlated with the KL grades (correlation coefficient: -0.688, P = 0.003); however, the changes in ST measurements were not significantly correlated with the KL grade.

CONCLUSIONS

Our exploratory cross-sectional analysis shows that SAD measurement changes during motion using 4DCT are correlated with the tibiotalar OA grading. This measurement may be used but requires confirmation in larger studies including patients with actual syndesmotic injuries.

Imaging Review of Hockey-related Lower Extremity Injuries

Hockey is a fast-paced contact sport with a high incidence of injuries. Although injuries are more frequent among elite players, recreational hockey injuries are a common issue faced by primary care and emergency physicians. Lower extremity injuries in hockey are particularly important because they account for approximately a third of all injuries and > 60% of all overuse injuries. This pictorial review provides the general and specialty trained radiologist with a knowledge of the patterns of lower extremity injury that occur in ice hockey.

Imaging Review of Snowboard Injuries

Snowboarding and skiing remain the two most popular winter sports worldwide. Musculoskeletal (MSK) injuries are common in snowboarding, and the number has increased significantly since the advent of snow parks. The number of injuries is the highest for novice snowboarders; more experienced boarders generally sustain more severe injuries. Snowboarders can experience a wide array of MSK injuries, but some injury types are more frequently encountered because of the specific injury mechanism unique to snowboarding. This article reviews the most common snowboarding injuries with a focus on the current understanding of the injury mechanism and provides an approach to imaging.

Tratamento da lesão da sindesmose tibiofibular distal associada às fraturas do tornozelo com suture button

Objetivo Avaliar os resultados obtidos do tratamento cirúrgico das fraturas maleolares do tornozelo associadas a lesão da sindesmose tibiofibular distal (STFD) submetidas a procedimento cirúrgico convencional de fixação da fratura e fixação da STFD pelo suture button (SB).

Métodos Avaliou-se retrospectivamente 49 pacientes com uma média de idade de 45 anos e seguimento médio de 34,1 meses. A avaliação clínica e funcional foi baseada na escala visual analógica (EVA) e na escala American Foot and Ankle Society Score (AOFAS, na sigla em inglês) para tornozelo e retropé, retorno às atividades da rotina e retorno ao esporte.

Resultados As médias pós-operatórias das escalas AOFAS e EVA foram, respectivamente, 97,06 (índice de confiança [IC 95%: 95,31 – 98,81] e 0,16 [IC 95% 0,04 – 0,29]. Todos os pacientes retornaram às atividades prévias do cotidiano, sendo que apenas 12 apresentaram algum sintoma residual. Não se verificou instabilidade pós-operatória em nenhum paciente. Ao todo, 46 pacientes retornaram às atividades desportivas e, destes, apenas 1 não retornou ao nível prévio à lesão. Apenas dois pacientes apresentaram alterações relacionadas ao SB. Não houve relato de insatisfação.

Conclusão Em fraturas maleolares do tornozelo com lesão da STFD, a fixação da sindesmose com o SB demonstrou excelentes resultados pós-operatórios.

Nível de Evidência IV, série de casos retrospectiva.

The ankle syndesmosis pivot shift "Are we reviving the ACL story?"

In recent literature, there is a growing interest for the high ankle sprain with emerging evidence on biomechanical behavior, function, injury, and treatment. Interpretation of emerging publications on the distal tibiofibular syndesmosis may raise questions about striking similarities with the anterior cruciate ligament function and pivot-shift mechanism of injury in the knee. This editorial note puts to question whether identical entities, a continuum or separate injuries are faced by contemplating on the mechanism of injury, diagnostics, treatment, and outcome.

Four-Dimensional CT Analysis of Normal Syndesmotic Motion

BACKGROUND

The syndesmosis ligament complex stabilizes the distal tibiofibular joint while allowing for small amounts of physiologic motion. When injured, malreduction of the syndesmosis is the most important factor that contributes to inferior functional outcomes. Syndesmotic reduction is a dynamic measure, which is not adequately captured by conventional computed tomography (CT). Four-dimensional CT (4DCT) can image joints as they move through range of motion (ROM). The aim of this study was to employ 4DCT to determine in vivo syndesmotic motion with ankle ROM in uninjured ankles.

METHODS

Uninjured ankles were analyzed in patients who had contralateral syndesmotic injuries, as well as a cohort of healthy volunteers with bilateral uninjured ankles. Bilateral ankle 4DCT scans were performed as participants moved their ankles between maximal dorsiflexion and plantarflexion. Multiple measures of syndesmotic width, as well as sagittal translation and fibular rotation, were automatically extracted from 4DCT using a custom program to determine the change in syndesmotic position with ankle ROM.

RESULTS

Fifty-eight ankles were analyzed. Measures of syndesmotic width decreased by 0.7 to 1.1 mm as the ankle moved from dorsiflexion to plantarflexion (P < .001 for each measure). The fibula externally rotated by 1.2 degrees with ankle ROM (P < .001), but there was no significant motion in the sagittal plane (P = .43). No participants with bilateral uninjured ankles had a side-to-side difference in syndesmotic width of 2 mm or greater.

CONCLUSION

4DCT allows accurate, in vivo syndesmotic measurements, which change with ankle ROM, confirming prior work that was limited to biomechanical studies. Side-to-side syndesmotic measurements are consistent within subjects, validating the method of templating syndesmotic reduction off the contralateral ankle, in a consistent ankle position, to achieve anatomic reduction of syndesmotic injury.

LEVEL OF EVIDENCE

Level II, prospective cohort study.

Syndesmosis Repair Affects in Vivo Distal Interosseous Tibiofibular Ligament Elongation Under Static Loads and During Dynamic Activities

BACKGROUND

Ligamentous ankle injuries are the most common injuries sustained by athletes and by the general population, with an incidence of approximately 2 million per year in the U.S. Injuries to the ankle syndesmosis (i.e., "high ankle sprains") are generally treated operatively. Although cadaveric studies can evaluate syndesmosis fixation strength, they cannot predict how healing, neuromuscular adaptation, or dynamic loading will affect in vivo biomechanics. Using dynamic biplane radiography (DBR), we tested the hypothesis that syndesmosis repair would restore ankle kinematics and ligament elongation during static and dynamic loading.

METHODS

A convenience sample of 6 male patients who had undergone fixation (2 screw, 3 suspensory, 1 hybrid) of syndesmosis injury were assessed with use of DBR during forward running, backpedaling, a 45° angled single-leg hop, and 1 static standing trial at 2 to 4.5 years postoperatively. Three-dimensional ankle kinematics and elongation of the distal interosseous ligament, anterior inferior tibiofibular ligament, and the posterior inferior tibiofibular ligament were measured bilaterally. Comparisons were made between the operative and uninjured sides. Clinical outcomes were evaluated with use of the Foot and Ankle Ability Measure.

RESULTS

Static load increased the lengths of the distal interosseous ligament (p = 0.02 to 0.05) and middle segment of the anterior inferior tibiofibular ligament (p = 0.02) in the operative ankle. The distal syndesmosis length was greater on the operative side during the static unloaded and loaded conditions (p = 0.02). Length of the distal syndesmosis on the operative side was greater than the corresponding healthy syndesmosis length during all 3 dynamic activities. On average, the operative ankle was in less dorsiflexion over the support phase of the angled hop (p = 0.05) and running (p < 0.01). The average Foot and Ankle Ability Measure Activities of Daily Living and Sports subscale scores were 95 and 88, respectively.

CONCLUSIONS

This study provides the first in vivo evidence of post-fixation changes in biomechanics after syndesmosis repair. Syndesmosis repair fails to restore healthy static and dynamic distal tibiofibular anatomy, even in patients who report good to excellent clinical outcomes.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

The Syndesmosis, Part I: Anatomy, Injury Mechanism, Classification, and Diagnosis

Ankle fractures are common injuries to the lower extremity with approximately 20% sustaining a concomitant injury to the syndesmosis. Although the deltoid ligament is not formally included in the syndesmotic complex, it plays an important role in the mortise stability. Therefore, its integrity should be always evaluated when syndesmotic injury is suspected. Given the anatomic variability of the syndesmosis between individuals, bilateral ankle imaging is recommended, especially in cases of subtle instability. Diagnostic tests that allow dynamic assessment of the distal tibiofibular joint in the 3 planes are the most reliable in determining the presence of syndesmotic injury.

Short-Term Effect of Manual Therapy &amp; Taping on Subacute Ankle Sprains with Potential Syndesmotic Sprain: A Case Series

STUDY DESIGN

Case Series.

BACKGROUND

Syndesmotic ankle sprains can occur in up to 17% of ankle trauma and can lead to long-term disability. This study describes the management of seven patients with subacute, high-grade ankle sprains with concerns of concurrent syndesmotic strain utilizing manual therapy and rigid sports taping.

METHODS

Seven active duty military members with clinically diagnosed, high-grade ankle sprains and concern for syndesmotic sprain participated in this case series. All patients received multi-modal treatment consisting of manual therapy, rigid sports taping, progressive exercises, and proprioceptive training. Decrease in Numeric Pain Rating Scale (NPRS) following manual therapy and taping treatment, number of sessions before discharge, and the Global Rating of Change (GROC) at discharge were retrospectively reviewed.

RESULTS

All patients demonstrated an immediate decrease in NPRS following treatment on average of 5 points (range, 3-8 points) with a functional asterisk sign. The improvement in pain and function was maintained until the next treatment session with a mean GROC score of +3. The mean time until recovery was 5.4 weeks (range, 1-8 weeks).

DISCUSSION

A multimodal approach for patients diagnosed clinically with high-grade ankle sprains and concern for syndesmotic sprain was useful to immediately reduce pain and improve function, and improvements were maintained throughout the duration of care. This study is the first to assess a combination of manual therapy and rigid sports taping for the treatment of suspected syndesmotic ankle sprains, and more stringent research is needed to validate the findings.

LEVEL OF EVIDENCE

Therapy, 4.

Functional outcomes of unstable ankle fractures with and without syndesmotic fixation in the adolescent population

PURPOSE

The purpose of this study was to compare functional outcomes of adolescents with and without ankle syndesmotic injuries and identify predictors of functional outcome after operative ankle fractures.

METHODS

A retrospective review was conducted on operative adolescent ankle fractures treated between 2009 and 2019 with a minimum of one-year follow-up (mean 4.35 years). Patients who underwent syndesmotic fixation (SF) (n = 48) were compared with operative ankle fractures without syndesmotic injury (n = 63). Functional outcomes were assessed using standardized questionnaires, specifically the Foot and Ankle Ability Measure (FAAM) and Single Assessment Numerical Evaluation.

RESULTS

There were no differences in patient-reported outcomes, rates of return to sport or complications between groups with and without SF. The SF group had a longer tourniquet time (p = 0.04), duration of non-weight-bearing (p = 0.01), more Weber C fibula fractures (p < 0.001), fewer medial malleolus fractures (p = 0.03) and more frequently underwent implant removal (p < 0.0001). Male sex, lower body mass index (BMI) and longer duration of follow-up were significant predictors of a higher FAAM sports score using multivariable linear regression. SF was not a predictor of functional outcome.

CONCLUSION

This study demonstrated that patients that undergo surgical fixation of syndesmotic injuries have equivalent functional outcomes compared to operative ankle fractures without intraoperative evidence of syndesmotic injury. We also identified that male sex, lower BMI and longer duration of follow-up are predictors of a good functional outcome.

LEVEL OF EVIDENCE

III.

Diagnostic Accuracy of Clinical Tests Assessing Ligamentous Injury of the Talocrural and Subtalar Joints: A Systematic Review With Meta-Analysis

Context:

Ankle sprains are the most common acute musculoskeletal injury. Clinical tests represent the first opportunity to assess the sprain’s severity, but no systematic review has compared these tests to contemporary reference standards.

Objective:

To determine the diagnostic accuracy of clinical tests assessing the talocrural and subtalar joint ligaments after ankle sprain.

Data Sources:

CINAHL, EMBASE, MEDLINE, hand-searching, and PubMed-related article searches (inception to November 18, 2020).

Study Selection:

Eligible diagnostic studies compared clinical examination (palpation, joint laxity) against imaging or surgery. Studies at a high risk of bias or with high concerns regarding applicability on Quality Assessment of Diagnostic Accuracy Studies-2 were excluded from the meta-analysis.

Study Design:

Systematic review and meta-analysis.

Level of Evidence:

Level 3a.

Data Extraction:

True-positive, false-negative, false-positive, and true-negative findings were extracted to calculate sensitivity, specificity, and likelihood ratios. If ordinal data were reported, these were extracted to calculate Cohen’s kappa.

Results:

A total of 14 studies met the inclusion criteria (6302 observations; 9 clinical tests). No test had both sensitivity and specificity exceeding 90%. Palpation of the anterior talofibular ligament is highly sensitive (sensitivity 95%-100%; specificity 0%-32%; min-max; n = 6) but less so for the calcaneofibular ligament (sensitivity 49%-100%; specificity 26%-79%; min-max; n = 6). Pooled data from 6 studies (885 observations) found a low sensitivity (54%; 95% CI 35%-71%) but high specificity (87%; 95% CI 63%-96%) for the anterior drawer test.

Conclusion:

The anterior talofibular ligament is best assessed using a cluster of palpation (rule out), and anterior drawer testing (rule in). The talar tilt test can rule in injury to the calcaneofibular ligament, but a sensitive clinical test for the ligament is lacking. It is unclear if ligamentous injury grading can be done beyond the binary (injured vs uninjured), and clinical tests of the subtalar joint ligaments are not well researched. The generalizability of our findings is limited by insufficient reporting on blinding and poor study quality.

Registration:

Prospero ID: CRD42020187848.

Data Availability:

Data are available in a public, open access repository on publication, including our RevMan file and the CSV file used for meta-analysis: http://doi.org/10.5281/zenodo.4917138

A Radiological Study for Assessing Syndesmosis Malreduction: Its Validity and Limitation

This study assessed the diagnostic utility of different X-ray radiological methods on syndesmosis malreduction. Thirteen fresh ankle specimens were used to make a syndesmotic separation model. The specimen was fixed in the anatomic position and in malreduction positions, including internal rotation 10° (IR10°), IR20°, external rotation 10° (ER10°), and ER20°. The tibiofibular clear space (TCS), tibiofibular overlap (TFO) on the anteroposterior view, and anteroposterior ratio (A/P ratio) on the lateral view were measured. When the syndesmosis was fixed in IR20°, the sensitivity of the TCS, TFO, and A/P ratio for malreduction diagnosis was 92.3% (12/13), 69.2% (9/13), and 100%, respectively. When the syndesmosis was fixed in IR10° malreduction, the sensitivity of the TCS, TFO, and A/P ratio for malreduction diagnosis was 38.4% (5/13), 38.4% (5/13), and 84.6% (11/13); in ER10°, 30.7% (4/13), 76.9% (10/13), and 69.2% (9/13); and in ER20°, 92.3% (12/13), 100% and 92.3% (12/13). In the anatomic reduction, the false-positive rate of the TCF, TFO, and A/P ratio was 7.6% (1/13), 7.6% (1/13), and 0%, respectively. The TFO and A/P ratio exhibited differences between all malreduction groups and the anatomic group. However, the TCS measurements had no statistical difference between the anatomic position and IR10° malreduction (p = .109). On the AP view, the TCS and TFO measurements are not sensitive enough to detect the syndesmosis malreduction. The A/P ratio on the lateral view exhibits better diagnostic utility for syndesmosis malreduction.

APKASS Consensus Statement on Chronic Syndesmosis Injury, Part 2: Indications for Surgical Treatment, Arthroscopic or Open Debridement, and Reconstruction Techniques of Suture Button and Screw Fixation

Background:

The indications for surgical treatment of chronic syndesmosis injury are challenging for many orthopaedic clinicians, as there is no international consensus on the optimal management of these injuries.

Purpose:

An international group of experts representing the field of sports injuries in the foot and ankle area was invited to collaboratively advance toward consensus opinions based on the best available evidence regarding chronic syndesmosis injury. All were members of the Asia-Pacific Knee, Arthroscopy and Sports Medicine Society (APKASS).

Study Design:

Consensus statement.

Methods:

From November to December 2020, a total of 111 international experts on sports medicine or ankle surgery participated in a 2-stage Delphi process that included an anonymous online survey and an online meeting. A total of 13 items with 38 statements were drafted by 13 core authors. Of these, 9 items with 17 clinical questions and statements were related to indications for surgical treatment, arthroscopic versus open debridement, and suture button versus screw fixation reconstruction techniques and are presented here. Each statement was individually presented and discussed, followed by a general vote. The strength of consensus was characterized as follows: consensus, 51% to 74%; strong consensus, 75% to 99%; and unanimous, 100%.

Results:

Of the 17 questions and statements, 4 achieved unanimous support, 11 reached strong consensus, and 2 reached consensus.

Conclusion:

This APKASS consensus statement, developed by international experts in the field, will assist surgeons and physical therapists with surgical indications and techniques for chronic syndesmosis injury.

Acute syndesmotic injuries in ankle fractures: From diagnosis to treatment and current concepts

A stable and precise articulation of the distal tibiofibular syndesmosis maintains the tibiofibular relationship, and it is essential for normal motion of the ankle joint. The disruption of this joint is frequently accompanied by rotational ankle fracture, such as pronation-external rotation, and rarely occurs without ankle fracture. The diagnosis is not simple, and ideal management of the various presentations of syndesmotic injury remains controversial to this day. Anatomical restoration and stabilization of the disrupted tibiofibular syndesmosis is essential to improve functional outcomes. In such an injury, including inadequately treated, misdiagnosed and correctly diagnosed cases, a chronic pattern characterized by persistent ankle pain, function disability and early osteoarthritis can result. This paper reviews anatomical and biomechanical characteristics of this syndesmosis, the mechanism of its acute injury associated to fractures, radiological and arthroscopic diagnosis and surgical treatment.

Deep deltoid ligament injury is related to rotational instability of the ankle joint: a biomechanical study

PURPOSE

In the athletic population, the prevalence of isolated syndesmotic lesions is high. To detect potential instability of the ankle is crucial to define those lesions in need of surgical management. The aim was to define how the extent of tibio-fibular syndesmotic ligament injury influences the overall stability of the ankle joint in a cadaver model.

METHODS

Twenty fresh-frozen through knee cadaveric leg specimens were subjected to different simulated syndesmotic ligament lesions. In Group 1 (n = 10), the order of ligament sectioning was: anterior tibio-fibular ligament (ATFL), superficial deltoid ligament (SDL), deep deltoid ligament (DDL), posterior tibio-fibular ligament (PTFL), and progressive sectioning at 10, 50 and 100 mm of the distal interosseous membrane (IOM). In Group 2 (n = 10), the sequence was: ATFL, PITFL, 10 and then 50 mm of the distal IOM, SDL, DDL, and 100 mm of the distal IOM. Diastasis of 4 mm in the coronal or sagittal plane and external rotation of the ankle greater than 20° were considered indicative of instability.

RESULTS

Both coronal and sagittal diastasis exceeded 4 mm with injury patterns characterized by IOM lesions extending beyond 5 cm. External rotation of the ankle exceeded 20° with injury patterns characterized by a DDL lesion.

CONCLUSION

Coronal and sagittal plane diastases of the tibio-fibular syndesmosis are particularly affected by sequential lesions involving the IOM, whereas increased external rotation of the ankle most depends on DDL. The identification of the specific syndesmotic and deltoid ligament injuries is crucial to understanding which lesions need operative management. The knowledge of which pattern of tibio-fibular syndesmotic ligament injury influences the ankle joint stability is crucial in defining which lesions need for surgical management.

Ankle injuries in athletes: A review of the literature

Ankle injuries are commonplace in the athletic population, with lateral ligament sprains accounting for the majority of them. The medial ligament complex, the distal tibiofibular syndesmosis as well as any of the bones that constitute the ankle joint can also be injured. Typical mechanisms of injury include inversion-plantarflexion and external rotation on a supinated, dorsiflexed or pronated foot. Lesions of the ankle present with similar symptoms of pain, swelling and tenderness. Therefore, a thorough history and physical examination must be obtained to make the correct diagnosis. This is especially critical for athletes as certain injuries can lead to termination of their career if not treated accurately on time. Imaging may be useful in some cases to confirm or rule out differential diagnoses. Most injuries can be managed conservatively using the Protection, Rest, Ice, Compression and Elevation protocol followed by a comprehensive rehabilitation programme. Surgery is reserved for grade III ligament tears that are refractory to initial non-operative treatment and displaced fractures that are unlikely to unite without surgical intervention. The objective of this review is to discuss the common ankle injuries encountered in the athletic population and the approaches to their diagnosis and management.

Diagnostic accuracy of clinical tests assessing ligamentous injury of the ankle syndesmosis: A systematic review with meta-analysis

OBJECTIVE

To summarise and evaluate research on the diagnostic accuracy of clinical tests for ligamentous injury of the ankle syndesmosis.

METHODS

CINAHL, Embase, and MEDLINE were searched from inception to February 12, 2021. Studies comparing clinical examination to arthroscopy, magnetic resonance imaging, or ultrasound were considered eligible. Meta-analysis was based on random effect modelling and limited to studies fulfilling all QUADAS-2 criteria. Sensitivity (SN), specificity (SP) and likelihood ratios determined diagnostic accuracy, all with 95% confidence intervals (CI).

RESULTS

Six studies were included (512 participants; 13 clinical tests; 29% median prevalence). No individual test was associated with both high sensitivity and high specificity. Tests with the highest sensitivity were: palpation [SN 92% (95%CI 79-98)] and dorsiflexion lunge [SN 75% (95% CI 64-84%); n = 2 studies]. Tests with the highest specificity were: squeeze test [SP 85% (95% CI 81-89%); n = 4 studies] and external rotation [SP 78% (95% CI 73-82%); n = 4 studies].

CONCLUSIONS

Clinical examination should involve initial clustering of tests with high sensitivity (palpation; dorsiflexion lunge), followed by a test with high specificity (squeeze). However, as these tests cannot definitively stratify syndesmotic injuries into stable vs unstable, decisions on optimal management (conservative vs surgery) require additional imaging or arthroscopy.

Physical Examination of the Ankle: A Review of the Original Orthopedic Special Test Description and Scientific Validity of Common Tests for Ankle Examination

Objectives

To review the literature, identify and describe commonly used special tests for diagnosing injury to the ligaments of the ankle complex, present the distinguishing characteristics and limitations of each test, and discuss the current evidence for the clinical use of each test.

Data Sources

Multiple PubMed (1920-2018) and CINAHL (1920-2018) searches were conducted and various musculoskeletal examination textbooks were reviewed to examine common orthopedic tests used to assess the ankle. The articles were reviewed for additional references and the search continued until the original description was found when possible.

Study Selection

All articles discussing the performance of the test or its validity (ie, sensitivity and specificity) were reviewed and summarized.

Data Extraction

Articles were reviewed for additional references and the search continued until the original description was found when possible.

Data Synthesis

The literature was reviewed, commonly used special tests for diagnosing ankle injuries were identified and described, distinguishing characteristics and limitations of each test were presented, and the current evidence for the clinical use of each test was discussed.

Conclusions

A complete physical examination is critical in the diagnosis of ankle injuries. The combination of available information such as mechanism of injury, all signs and symptoms, and changes in gait, is key to a conclusive and correct diagnosis. Clinicians should be aware of the severely limited evidence supporting the use of many commonly used special tests. Applying evidence from the literature will improve diagnostic accuracy. Further research is needed to understand the performance ability of special tests, both individually and when grouped as part of a test battery.

Biomechanical comparison of suture-button, bioabsorbable screw, and metal screw for ankle syndesmotic repair: A meta-analysis

BACKGROUND

To compare biomechanically metal screw fixation to suture-button or bioabsorbable screw fixation for ankle syndesmotic injuries.

METHODS

A literature search of the comparison studies in Pubmed and Google Scholar was conducted. The biomechanical outcomes of interest were syndesmotic stability in the coronal, sagittal, and axial planes as well as torque and rotation at failure.

RESULTS

A total of 11 cadaveric studies were included. In the suture-button group, coronal displacement (MD 1.72mm, p = 0.02) and sagittal displacement (MD 2.65mm, p = 0.0003) were increased relative to the metal screw group. In contrast, no difference was found with axial rotation (MD 0.35 degrees, p = 0.57). Bioabsorbable screws exhibited equivalent failure torque (MD -3.04Nm, p = 0.53) and rotation at failure (MD 3.77 degrees, p = 0.48) in comparison to metal screws.

CONCLUSIONS

Suture-button provide less rigidity when compared to metal screw fixation. They afford flexible syndesmotic micromotion which may more closely resemble a physiological state and be helpful for ligament healing. Bioabsorbable screws demonstrate similar mechanical strength properties to metal screws.

Weightbearing Cone-Beam Computed Tomography of Acute Ankle Syndesmosis Injuries

Syndesmotic injuries are common, but only a subset of these injuries are unstable. A noninvasive tool for identifying instability would aid in the selection of patients for surgery. Weightbearing computed tomography (CT) data have been reported for healthy patients, but there are limited data on unstable syndesmoses. We evaluated the syndesmotic area of arthroscopically proven unstable ankles after acute injury. This is a prospective comparative study of consecutive patients recruited to a weightbearing CT database. Thirty-nine patients were included for analysis with arthroscopically proven unstable syndesmoses and an uninjured contralateral ankle. The syndesmosis area was measured for both ankles, in non-weightbearing and weightbearing positions, and compared. Syndesmosis area of the unstable ankle was significantly greater than the uninjured ankle of the same patient, by a mean of 22.9 ± 10.5 mm². This was a significantly greater difference than that observed with non-weightbearing CT (9.8 ± 10.2 mm², p < .001). Dynamic change in area, from non-weightbearing to weightbearing, of the unstable ankle (13.7% [16.6 ± 9.9 mm²]) was significantly greater than that of the uninjured ankle (3.1% [3.4 ± 6.7 mm²], p < .001). The intraobserver and interobserver correlations were good with intraclass correlation coefficients of 0.983 and 0.970, respectively. Weightbearing CT demonstrated significantly greater diastasis in unstable ankles than did conventional non-weightbearing CT. Syndesmosis area measurement was reliable and reproducible. Dynamic change in area and weightbearing comparison with the contralateral uninjured ankle are 2 parameters that may prove useful in the future for predicting syndesmotic instability.

Injury mechanism affects the stability of suture-button syndesmosis fixation

BACKGROUND

Ankle syndesmosis injury is a common condition, and the injury mechanism can be sorted into pure syndesmosis injury, Weber-B, and Weber-C type fractures. This study aims to evaluate the treatment outcomes and stability of suture-button fixation for syndesmosis injury with different injury mechanisms. We hypothesized that injury mechanisms would alter the stability of suture-button fixation.

METHODS

We retrospectively reviewed 63 patients with ankle syndesmosis injury who underwent surgery with TightRope (Arthrex, Naples, FL, USA) from April 2014 to February 2019. The stability of suture-button fixation with TightRope was evaluated by comparing the preoperative, postoperative, and final follow-up measurements of tibiofibular clear space (TFCS), tibiofibular overlap (TFO), and medial clear space (MCS). A subgroup analysis for each demographic group and injury type including pure syndesmosis injury, Weber-B, and Weber-C type fractures were performed.

RESULTS

Syndesmosis was effectively reduced using TightRope. After the index surgery, the tibiofibular clear space was reduced from 7.73 to 4.04 mm, the tibiofibular overlap was increased from 3.05 to 6.44 mm, and the medial clear space was reduced from 8.12 to 3.54 mm. However, syndesmosis widening was noted at the final follow-up, especially in Weber-C type fractures (TFCS 3.82 to 4.45 mm, p < 0.01 and TFO 6.86 to 6.29 mm, p = 0.04). Though widened, the final follow-up values of tibiofibular clear space and tibiofibular overlap were in the acceptable range. Postoperatively and at the final follow-up, medial clear space was found to be significantly larger in the Weber-C group than in the pure syndesmosis and Weber-B groups (p < 0.05).

CONCLUSIONS

Suture-button fixation can offer anatomic reduction and dynamic fixation in syndesmosis injuries. However, when using this modality for Weber-C type fractures, more attention should be focused on the accuracy of reduction, especially of medial clear space, and rediastasis should be carefully monitored.

TRIAL REGISTRATION

This trial was retrospectively approved by TMU-JIRB. Registration number N202004122, and the date of approval was May 06, 2020.

LEVEL OF EVIDENCE

III.

Immediate Effects of Ankle Joint Mobilization With Movement on Postural Control, Range of Motion, and Muscle Strength in Healthy Individuals: A Randomized, Sham-Controlled Trial

CONTEXT

Ankle proprioception is one of the crucial components contributing to postural control. Although the effects of Mulligan's mobilization with movement (MWM) on postural control, ankle dorsiflexion range of motion (DFROM), and muscle strength in people with ankle disorders have previously been investigated, it is still unclear whether ankle MWM had ability to change postural control, DFROM, and muscle strength.

OBJECTIVES

To reveal pure effects of MWM on postural control, ankle DFROM, and muscle strength in healthy individuals.

DESIGN

A prospective, randomized, double-blinded, sham-controlled study.

SETTING

Musculoskeletal laboratory, Dokuz Eylul University, Turkey.

PARTICIPANTS

Forty students in good health recruited from a local university.

INTERVENTIONS

Mulligan's MWM or sham application over ankle joint.

MAIN OUTCOME MEASURES

The primary outcome was postural control and measured using limits of stability (LOS) test. The secondary outcomes were tibialis anterior muscle strength and ankle DFROM, which were measured using handheld dynamometer and weight-bearing lunge test, respectively. All outcomes were assessed before and immediately after intervention.

RESULTS

Left and right ankle DFROM and LOS overall score showed a statistically significant improvement compared with first measurement in both groups (P < .05). However, LOS time was significantly improved only in the MWM group (P < .05). Statistical analyses of between-group mean differences showed that Mulligan's MWM provided significant improvement in the LOS in forward-right direction compared with sham application (P = .03).

CONCLUSIONS

The results of this study suggest that the application of Mulligan's MWM on ankle joint might be beneficial to improve postural control in forward right direction in individuals with healthy ankles. On the other hand, both MWM and sham application were able to increase overall postural control and DFROM, and MWM had no superiority over sham application for increasing these 2 variables.

Mechanisms of acute ankle syndesmosis ligament injuries in professional male rugby union players: a systematic visual video analysis

BACKGROUND

The mechanisms of acute ankle syndesmosis ligament injuries in professional rugby union are not well understood.

AIM

To describe the mechanisms of acute ankle syndesmosis ligament injuries in male professional rugby union players using systematic visual video analysis.

METHODS

All time-loss acute ankle syndesmosis ligament injuries identified via retrospective analysis of the Leinster Rugby injury surveillance database across the 2013/2014 to 2017/2018 seasons were considered as potentially eligible for inclusion. Three Chartered Physiotherapists (analysts) independently assessed all videos with a final consensus meeting convened to describe the injury mechanisms. One of the analysts developed a qualitative description of each injury mechanism.

RESULTS

Thirteen acute ankle syndesmosis injuries were included in this study. The most common biomechanical presentation of the injured limb was characterised by hip flexion, knee flexion, knee valgus, ankle dorsiflexion, pronation and external rotation of the foot. Six of the included injuries (46%) were the result of an external load application to the injured limb (ie, direct contact injuries). In the other seven instances (54%), the injury was the result of a collapse of the injured player's body mass over the injured ankle joint, while tackling or being tackled, without direct contact to the injured limb (ie, indirect contact injuries).

CONCLUSION

Injuries incurred while tackling were exclusively the result of suboptimal tackle mechanics. A majority of injuries incurred while being tackled involved a posterior tackle, which often resulted in a posterior collapse of the injured player's centre of mass over a fixed externally rotated foot.

Revision of the Chronic Syndesmotic Injury

Optimal healing for fractures requires anatomic reduction and stable fixation. This optimizes not only bone healing, but optimal function within the limb including joint functioning. Proper ligamentous healing is also crucial for optimal functioning. In patients with injuries around the ankle involving distal tibiofibular syndesmotic injuries of the ankle, malreduction of the syndesmosis is a potential consequence that can lead to chronic pain and functional limitations. This article discusses proper ways of evaluating reduction of the syndesmosis and surgical revision for the chronic injury.

Evaluating success rate and comparing complications of operative techniques used to treat chronic syndesmosis injuries

Purpose

To assess the success rate and complications of the surgical interventions used to manage chronic syndesmosis injuries.

Methods

Multiple online databases were queried to identify studies reporting operative intervention for chronic syndesmosis injuries.

Results

Modalities of operative fixation include suture-button fixation, arthroscopy and debridement, as well as arthrodesis. The use of operative treatment is effective; however, more direct comparison studies are necessary to evaluate the efficacy of each treatment.

Conclusion

Various operative procedures have been used for the management of chronic syndesmotic injuries but further prospective studies are necessary to determine the type of treatment that should be indicated.

Motion of the distal tibiofibular syndesmosis under different loading patterns: A biomechanical study

PURPOSE

The distal tibiofibular syndesmosis is an important structure for ankle stability. The objective of this study was to evaluate the motion of the syndesmosis under different loading patterns and determine the characteristics of the syndesmotic motion.

METHODS

Six fresh cadaveric lower extremity specimens with the knee reserved were tested in this study. The skin and muscles were removed with all ligaments around the syndesmosis and knee and ankle joint intact. An axial load of 600 N was applied to the specimens with the ankle joint in 10° dorsiflexion, neutral position, and 15° plantar flexion using a universal material testing machine. Then, with the ankle joint positioned neutrally, a combination of 600-N axial and 5-Nm torsional external rotation loading was applied to the specimens. The medial-lateral and anterior-posterior displacement and rotation of the distal fibula relative to the distal tibia were measured.

RESULTS

Under the axial loading, the distal fibula tended to move medially and anteriorly and rotate internally with the ankle positioned from the neutral position to 15° plantar flexion. Meanwhile, when the ankle was positioned from the neutral position to 10° dorsiflexion, the distal fibula tended to move laterally and posteriorly and rotate externally. Under the combined loading, with respect to the isolated axial loading, the distal fibula tended to move medially and posteriorly, and rotate externally relative to the distal tibia.

CONCLUSION

Micro motion existed in the syndesmosis. The relative motion of the syndesmosis was correlated to the ankle position and loading patterns.

High ankle sprain: sonographic demonstration of a posterior inferior tibiofibular ligament avulsion

Syndesmotic injuries, also referred as high ankle sprains, may cause significant ankle instability and chronic pain. Ultrasound (US) is a well-proven imaging modality to evaluate the ligaments of the ankle, due to its high spatial resolution and the possibility to perform dynamic examinations. However, considering the syndesmosis complex, the sonographic appearance of the posterior inferior tibiofibular ligament (PITFL) is not well described in the pertinent literature and, to the best of our knowledge, we found no report of PITFL avulsion demonstrated at US, as in the case presented.

Revision of Syndesmosis Screw Fixation

Background: Many syndesmosis screw fixations do not achieve success at the first attempt. Currently, there are no data available to evaluate revision of syndesmosis screw failure. Methods: A total of 160 consecutive patients who underwent syndesmosis screw fixation from 2014 to 2016 were reviewed. The current study focuses on 13 of 160 patients who underwent revision surgery and analyzes reasons, methods, and outcomes of syndesmotic screw revisions. Results: Thirteen out of 160 patients had revision surgeries. Incidence of recurrent diastasis was 92.3%. Seven out of 19 screws had broken. Two patients had screw loosening, 9 patients underwent early weightbearing, 1 patient developed osteomyelitis, 1 patient developed osteoarthritis, and 1 patient had fibular nonunion. Eleven patients underwent removal, 3 patients underwent clamp reduction, and 4 patients underwent fibular osteotomy. Six patients experienced good reduction with 0/10 pain, 3 patients experienced good reduction with some pain, 1 patient experienced poor reduction; 1 patient developed osteomyelitis and subsequent 7/10 pain; 1 patient underwent fusion with 5/10 pain, and 1 patient experienced medial malleolar mal-union with 3/10 pain. Conclusion: It was found that the main reason for syndesmosis revision was reoccurring diastasis. Most patients ultimately experienced good reduction and were able to ambulate, despite some residual pain. Levels of Evidence: Level IV: Case series.

Validation and application of dynamic biplane radiography to study in vivo ankle joint kinematics during high-demand activities

Ankle ligament injuries are the most common musculoskeletal injury in physically active populations. Failure to restore native kinematics post-injury often leads to long-term consequences including chronic instability and arthritis. Using traditional motion capture, it is difficult to distinguish independent motions of the tibiotalar and subtalar joints to assess the effects of injury, surgical repair, and rehabilitation on ankle joint complex (AJC) kinematics. Therefore, the aims of this study were to determine the accuracy of dynamic biplane radiography for determining in vivo AJC kinematics and arthrokinematics, and to identify sport-related movements that require the largest AJC range of motion (ROM) during support. Two subjects had three to five 1.0 mm diameter tantalum beads implanted into the tibia, fibula, talus, and calcaneus during lateral ankle ligament repair. Six months after surgery, the subjects executed seven movements while biplane radiographs were collected. Bone motion was tracked using radiostereophotogrammetric analysis (RSA) as a "gold standard", and compared to a volumetric CT model-based tracking algorithm that matched digitally reconstructed radiographs to the original biplane radiographs. Over all movements, the average tibiotalar, subtalar and tibiofibular RMS errors were 0.5 mm ± 0.2 mm, 0.8 mm ± 0.5 mm and 0.8 mm ± 0.3 mm in translation and 1.4° ± 0.4°, 1.5° ± 0.5° and 1.7° ± 0.6° in rotation, respectively. Tibiotalar joint space was determined with an average precision of 0.5 mm. ROM results indicate that jumping and a forward-to-backward push-off movement are the best of the seven sport-related movements evaluated for eliciting full ROM kinematics.

Dynamic fixation is superior in terms of clinical outcomes to static fixation in managing distal tibiofibular syndesmosis injury

PURPOSE

To analyze the current randomized controlled trials (RCTs) of dynamic fixations (DFs) and static fixations (SFs) in treating distal tibiofibular syndesmosis injuries (DTSIs).

METHODS

The Cochrane Central Register of Controlled Trials, PubMed, and EMBASE were systematically searched according to the PRISMA guidelines to identify RCTs comparing the DFs and SFs for DTSIs. Included studies were assessed using the Cochrane Risk of Bias Tool. Postoperative functional scores, range of motion (ROM), complication rate, and incidence of reoperation were statistically analyzed using review manager software, and a p value of < 0.05 was considered statistically significant.

RESULTS

Five RCTs with a total of 282 patients were included. Analysis revealed statistically significant differences in favor of DFs with regard to American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot score at a follow-up less than 6 months (MD 5.29; 95% CI 0.99-9.59; p = 0.02; I² = 0%) and at a follow-up more than 2 years (MD 7.53; 95% CI 3.30-11.76; p = 0.0005; I² = 0%), Olerud-Molander ankle (OMA) score at 1 year follow-up (MD 4.62; 95% CI 0.91-8.32; p = 0.01; I² = 14%), and overall postoperative complication rate (RR 0.22; 95% CI 0.07-0.77; p = 0.02; I² = 73%). There was no significant difference between the DFs and SFs regarding ROM and incidence of reoperation.

CONCLUSIONS

The DF procedure leads to significantly improved functional scores as well as lower rate of overall postoperative complications when compared with SF procedure. On the basis of results of this meta-analysis, the DF should be recommended for managing the DTSI.

LEVEL OF EVIDENCE

I.