Deltoid Ligament Injury Research Articles

Risk Factors for Chronic Syndesmotic Instability After the First Episode of Acute Ankle Sprain: A Cross-Sectional Study of 356 Cases.

Chronic syndesmotic instability (CSI) can be associated with severe long-term pain and disability. This study aimed to investigate the risk factors associated with the development of CSI in patients who underwent conservative treatment after the first episode of acute ankle sprain (AAS) that did not result in a satisfactory outcome. We retrospectively analyzed the clinical data of patients who underwent ankle arthroscopy for suspected CSI between January 2020 and September 2023. The patients were divided into the instability and stability groups based on the syndesmotic space width measured under arthroscopy, with 3 mm as the critical value. Demographic, arthroscopic, and imaging information such as the anterior talofibular ligament (ATFL), calcaneofibular ligament, posterior talofibular ligament (PTFL), anterior inferior tibiofibular ligament (AITFL), posterior inferior tibiofibular ligament (PITFL), deltoid ligament (DL), interosseous membrane, height of the syndesmotic fluid, injuries of the talus, calcaneus, tibia, and fibula, effusion of the tibiotalar and talocalcaneal joints, fibular morphology, and fibular incisura features, were recorded. Univariate and multivariate analyses were performed successively to identify the risk factors. Of the 356 patients, 102 developed CSI after the first episode of AAS. In the multivariate analysis, development of CSI was associated with 5 clinical factors: DL injury (odds ratio [OR] 7.453, 95% CI 3.007-18.471; P < .001), positive bandage-binding test (OR 7.196, 95% CI 2.942-17.599; P < .001), grade 2 to 3 injury of the PITFL (OR 2.727, 95% CI 1.044-7.124; P = .041), positive squeeze test (OR 2.455, 95% CI 1.045-5.770; P = .039), and body mass index (BMI) (OR 1.306, 95% CI 1.121-1.522; P < .001). Five key factors were associated with CSI development in patients who underwent conservative treatment after the first episode of AAS that did not result in a satisfactory outcome: DL injury, positive bandage-binding test, grade 2 to 3 injury of the PITFL, positive squeeze test, and BMI.

Modified double-row suture bridge technique for anterior colliculus fractures combined with deltoid ligament injury: a retrospective study

BackgroundThe management of anterior colliculus fractures in combination with deltoid ligament injuries is a topic of debate, and there is a need to improve surgical outcomes. The purpose of the present study was to describe the application of a modified double-row suture bridge technique and evaluate its early clinical outcomes in the management of anterior colliculus fracture combined with deltoid ligament injury.MethodsFrom 2020 to 2022, 12 patients with anterior colliculus fracture combined with deltoid ligament injury were treated using a modified double-row suture bridge technique. For clinical outcome evaluation, objective data are presented through clinical examination findings; radiographic assessments, including X-rays and computed tomography (CT); and follow-up analysis utilizing American Orthopaedic Foot & Ankle Society ankle‒hindfoot (AOFAS) scores, Olerud Molander Ankle Scores (OMAS), and visual analogue scale (VAS) scores. Preoperative and follow-up scores were compared with Student’s t test. (p < .05).ResultsThe mean age of the patients was 52.67 ± 9.42 years (range: 39–74). The mean duration of follow-up was 14.42 ± 1.51 months (range: 12–17). At the final follow-up, the mean AOFAS score (P < 0.001) improved to 91.50 ± 2.65 points (range: 87–96), the mean OMAS (P < 0.001) improved to 77.08 ± 3.97 points (range: 70–85), and the mean VAS score (P < 0.001) improved to 0.25 ± 0.45 points (range: 0–1). Nine patients achieved excellent outcomes, and three achieved good outcomes according to the AOFAS score. Follow-up imaging evaluation indicated satisfactory alignment of the fracture and complete healing. Clinical examination suggested good mobility of the ankle. At the last follow-up, ankle dorsiflexion mobility was 14–18 degrees, plantar flexion mobility was 42–45 degrees, inversion mobility was 27–32 degrees, and eversion mobility was 22–25 degrees.ConclusionsThe modified double-row suture bridge technique is effective for achieving anatomic reduction of anterior colliculus fractures, and the technique also provides substantial benefit to the injured deltoid ligament. With this technique, the clinical outcomes can be significant and encouraging, indicating a new stage in its application and development.

Syndesmotic and Deltoid Injuries: Companions or Coincidences.

Syndesmotic complex injuries are supposedly associated with injuries to the deltoid ligament (DL) complex. Several syndesmosis classifications take DL injuries into account when rating the stability of the syndesmotic injury. Still, no study has yet assessed the frequency and severity of DL injuries in unstable syndesmotic injuries. The aim of this retrospective cohort study was to assess both the severity of the syndesmotic and DL injury in patients undergoing surgery for an unstable syndesmotic injury. The integrity of the syndesmotic and DL complex of 37 patients were assessed on MRI by 2 musculoskeletal radiologists. Eligible were adult patients with an acute, isolated, unstable syndesmotic injury (ligamentous or bony avulsions) who underwent surgery. The DL complex was classified as having 3 superficial (TNL/TSL/TCL) and 2 deep (aTTL/pTTL) components. Grade 0 indicated an intact ligament; grade I showed a periligamentous edema; grade II a partial tear presenting as laxity, irregular contour, or partial discontinuity with concomitant hyperintense signaling; grade III a complete tear; or grade IV in case of an avulsion fracture. Frequency and severity of DL injuries were assessed, and possible injury combinations analyzed using an h-cluster analysis and Mann-Whitney U test. Mean severity (grade 0-3) was 2.6 ± 0.8 for the syndesmotic complex and 1.6 ± 1.1 for the DL (superficial 1.5 ± 1.1, deep 1.6 ± 1.1). Seven patients (19%) had no (n = 3; 8%) or minor (grade 1: n = 4; 11%) DL injuries. Overall, 2 different patient clusters and 4 separate ligament clusters were identified. Unstable syndesmotic injuries can occur isolated or with an accompanying DL injury. There appears to be a great heterogeneity between the severity of syndesmotic and deltoid ligament injuries.

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

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 ligamentand treatment recommendations. 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 diagnosisor treatment methods. 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 injuryor larger studies of treatment pathways. Long-term studies of the incidence of instability in deltoid ligament injuries were not available. 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 IV.

Functional Anatomy of the Rear Attachment of the Deep Deltoid (RAD) Ligament of the Ankle.

The deltoid ligament plays a key role in ankle stability. Ankle fractures involving the medial ligamentous complex are evaluated on the basis of medial-sided tenderness and the Ottawa ankle rules. Evolution in our understanding of this ligament over the last three decades has shown that, within this medial ligamentous complex, it is the deep deltoid ligament that confers mechanical stability. The latest evolution in this understanding, and the learning point of this report, is that only a distinct component of the deep deltoid ligament - specifically the discreet posterior third - the rear attachment of the deep deltoid ligament (RAD) - confers mechanical value. The RAD is responsible for providing the medial ligamentous component of ankle stability - specifically talar shift, tilt, and importantly rotational stability. This knowledge is of key importance in the assessment and management of ankle fractures with associated deltoid ligament injuries. In this technical report, we highlight the biomechanical contribution of the RAD, which will help surgeons and physiotherapists to accurately manage ankle injuries.

Investigation into the effect of deltoid ligament injury on rotational ankle instability using a three-dimensional ankle finite element model.

Injury to the lateral collateral ligament of the ankle may cause ankle instability and, when combined with deltoid ligament (DL) injury, may lead to a more complex situation known as rotational ankle instability (RAI). It is unclear how DL rupture interferes with the mechanical function of an ankle joint with RAI. To study the influence of DL injury on the biomechanical function of the ankle joint. A comprehensive finite element model of an ankle joint, incorporating detailed ligaments, was developed from MRI scans of an adult female. A range of ligament injury scenarios were simulated in the ankle joint model, which was then subjected to a static standing load of 300N and a 1.5Nm internal and external rotation torque. The analysis focused on comparing the distribution and peak values of von Mises stress in the articular cartilages of both the tibia and talus and measuring the talus rotation angle and contact area of the talocrural joint. The dimensions and location of insertion points of ligaments in the finite element ankle model were adopted from previous anatomical research and dissection studies. The anterior drawer distance in the finite element model was within 6.5% of the anatomical range, and the talus tilt angle was within 3% of anatomical results. During static standing, a combined rupture of the anterior talofibular ligament (ATFL) and anterior tibiotalar ligament (ATTL) generates new stress concentrations on the talus cartilage, which markedly increases the joint contact area and stress on the cartilage. During static standing with external rotation, the anterior talofibular ligament and anterior tibiotalar ligament ruptured the ankle's rotational angle by 21.8% compared to an intact joint. In contrast, static standing with internal rotation led to a similar increase in stress and a nearly 2.5 times increase in the talus rotational angle. Injury to the DL altered the stress distribution in the tibiotalar joint and increased the talus rotation angle when subjected to a rotational torque, which may increase the risk of RAI. When treating RAI, it is essential to address not only multi-band DL injuries but also single-band deep DL injuries, especially those affecting the ATTL.

Effects of Fibular Plate Fixation on Ankle Stability in a Weber B Fracture Model With Partial Deltoid Ligament Sectioning.

Weber B fractures with concomitant deltoid ligament injury have traditionally been operated with open reduction and internal fixation of the fibular fracture. More recently, clinical studies have suggested that some fractures have concomitant partial deltoid ligament injury with the deep posterior tibiotalar ligament intact (SER4a), allowing for nonoperative treatment in this subgroup. This study explores whether plate fixation of the fibula improves ankle stability in an SER4a injury model. And if so, does it restore native ankle stability? Fifteen cadaver ankle specimens were tested in 3 states using an industrial robot: intact joint, SER4a models without plate fixation of the fibula, and SER4a models with plate fixation of the fibula. The robot measured ankle stability in lateral translation, valgus, and internal and external rotation in 3 talocrural joint positions: 10 degrees dorsiflexion, neutral, and 20 degrees plantar flexion. Furthermore, fluoroscopic mortise view radiographs were taken to measure isolated talar shift and talar tilt. The talar shift and tilt tests showed no differences between the SER4a injury model with and without fibular plate fixation at neutral ankle position with a mean difference of -0.16 mm (95% CI -0.33 to 0.01 mm, P = .071) for talar shift and -0.15 degrees (95% CI -0.01 to 0.30 degrees, P = .068) for talar tilt. However, plate fixation increased external rotation stability, with mean improvements ranging from -7.43 to -9.52 degrees (P < .001 for all comparisons), but did not restore intact ankle stability. For internal rotation, plate fixation resulted in minor differences. The results of this suggest that plate fixation of the fibular fracture primarily improves external rotation stability but does not substantially improve lateral translation, valgus, or internal rotation stability in SER4a injury models. In this robotic cadaver model, fibular plate fixation did not fully restore intact ankle stability after simulated SER4a injury. This study offers insights into the effects of fibular plate fixation on Weber B/SER4a injury models and may assist informed decisions when selecting treatments for these types of fractures.

Ankle arthroscopy does not elevate complication rates in ankle fractures

IntroductionAnkle fractures rank as the second most common lower limb fractures, and surgical intervention is essential for unstable ankle fractures. The use of ankle arthroscopy in such cases offers several advantages. This study aim is to assess whether arthroscopy influenced on complication rates in 171 ankle fractures treated with arthroscopic assistance. MethodsThis retrospective epidemiological analysis encompassed adult ankle fractures between December 2018 and December 2021. Initially, 173 patients were considered, but two were excluded, leaving a final sample of 171 patients. Postoperative complications were categorized as major or minor. ResultsThe study included 171 patients with surgically treated ankle fractures assisted by arthroscopy, comprising 76 females and 95 males, with an average age of 41.9 years. Syndesmosis injuries were treated in all diagnosed cases (55.0%), and deltoid ligament injuries received attention when identified (33.7%). Arthroscopic techniques were preferred over open techniques (47.4%). Ten patients experienced complications, consisting of 2 major and 8 minor complications (5.8%). DiscussionOur study's epidemiological findings align with prior literature, demonstrating that intra-articular injuries accompany 63% to 79% of ankle fractures. Arthroscopy allows for both diagnosis and treatment within the same procedure, including joint lavage to reduce inflammation. We diagnosed 57 deltoid injuries and identified a statistical relationship between chondral, syndesmotic, and deltoid ligament injuries. Infection is a common complication in ankle fracture surgery, with rates ranging from 1.44% to 16%. Our study yielded a 5.8% complication rate, comprising 1.2% major and 4.6% minor complications. Patients undergoing ORIF with arthroscopic assistance had a lower prevalence of infection. ConclusionThe use of arthroscopic assistance in the surgical treatment of ankle fractures does not increase the overall complication rate. Level of evidenceIV

Patient-Reported Outcomes Following Open Broström-Gould Procedure: Minimum 5-Year Follow-Up.

Ankle sprains are a common musculoskeletal injury among the general population and often involve the lateral ligament complex. Although the majority of ankle sprains are treated successfully with nonsurgical conservative measures, an estimated 5% to 20% of ankle injuries ultimately develop chronic lateral ankle instability (CAI). Multiple surgical treatment modalities for the lateral ankle complex exist, such as anatomical and nonanatomical reconstruction. The current gold standard for primary surgical repair is the Broström-Gould procedure. This is the first article to provide PROMIS scores following BG and the largest study with 5-year outcomes for an open BG. This was a descriptive study of a retrospective cohort of patients undergoing a BG with a minimum follow-up of 5 years. Patient-reported outcome instruments collected postoperatively were PROMIS Pain, Physical Function, Depression, and FAAM. Further preoperative clinic characteristics were analyzed to correlate with the final outcome. The electronic medical record was queried for Current Procedural Terminology (CPT) code 27698 (Broström-Gould) from January 2010 to June 2017. Surveys were conducted in the clinic and through phone interviews. Patient charts were reviewed to obtain basic patient demographic information including sex, age, race, and body mass index (BMI). The following preoperative variables were recorded: history of prior CAI procedures, history of major trauma, duration of symptoms, number of diagnosed ankle sprains, other collagen pathologies, generalized ligament laxity, participation in sports/activity level, peroneal subluxation, clinically diagnosed peroneus longus or brevis tendinopathy, deltoid ligament injury, anterior ankle impingement, and posterior ankle impingement. The PROMIS and Foot and Ankle Ability Measure (FAAM) scores were obtained with a combination of clinic and phone interviews. Data were aggregated in Microsoft Excel and entered in R (version 4.2.0) for statistical analysis. Our results show that the minimum 5-year patient-reported PROMIS scores for patients following a Broström-Gould procedure are as follows: PROMIS physical function, 50.5; PROMIS pain interference, 48.2; and PROMIS depression, 38.2. This indicates, at a minimum, that patients 5 years removed from the procedure are within 1 SD of the general population in regard to PROMIS physical function and pain. Our patient-reported FAAM, activities of daily living, and FAAM sports scores were 59.6 and 13.0 respectively. Preoperative magnetic resonance imaging (MRI) findings were recorded. Arthroscopic examination was performed before lateral ligaments reconstruction for patients with intra-articular pathologies confirmed on MRI. The findings from our study offer evidence supporting the effectiveness of the Broström-Gould procedure to be associated with normal physical function, even 5 years after surgery. Furthermore, our research identified specific factors such as tobacco use, diabetes, and sports participation that independently correlated with reported outcome measures. These insights enable physicians to better manage patient expectations and tailor treatment strategies accordingly. Our study establishes a foundation for future prospective research endeavors that aim to leverage the PROMIS system for comprehensive outcome assessments. Level III, retrospective cohort study.

Kirschner Wire Internal Fixation of the Medial Tibiotalar Joint for Indirect Repair of Deltoid Ligament Injury: A Retrospective Comparative Study.

Ankle joint fractures are often accompanied by medial deltoid ligament rupture. There is controversy over whether or how to treat deltoid ligament rupture. This study was aimed to explore the feasibility of repairing the medial deltoid ligament using Kirschner wire internal fixation of the medial tibiotalar joint combined with external fixation. Forty-six patients with ankle fractures involving deltoid ligament rupture, treated between October 2012 and February 2021, were retrospectively evaluated. Twenty-five patients were treated with a Kirschner wire to fix the tibiotalar joint and indirectly repair the deltoid ligament as the repaired group. Twenty-one patients underwent reduction and fixation of internal and external malleolus fractures, and the deltoid ligament was not repaired in the unrepaired group. The American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score, visual analog scale (VAS), Medical Outcomes Short Form 36-item questionnaire score (SF-36), and Medial clear space perpendicular (preoperative, postoperative, final follow-up) were used for functional evaluations and reduction assessments. Mann-Whitney test were used to compare the differences between the groups. The follow-up time was 13-112 months with a mean of 59.32 months for the repaired group and 11-94 months with a mean of 53.43 months for the unrepaired group. There was no significant difference in the operative time or intraoperative blood loss between the two groups (p > 0.05). At the last follow-up, the AOFAS ankle-hindfoot and SF-36 scores of the repaired group were significantly higher than those of the non-repaired group (p < 0.05). Moreover, the VAS pain score was significantly lower and the Medial clear space perpendicular was significantly narrower in the repaired group than that in the unrepaired group. Tibiotalar joint fixation using Kirschner wires is a simple and effective technique that can indirectly reduce and repair the deltoid ligament and stabilize the ankle.

Healed ORIF in a fibula fracture – Hardware removal or hardware retention for the fibula in a patient with minor symptoms?

- A 31yo female is involved in a fall while climbing on some wet rocks. She was brought into the emergency department and was found to have suffered a closed fracture of the right fibula with a deltoid ligament injury. Distal neurovascular exam was normal. She is otherwise unhurt. She had ORIF of her ankle injury and it has gone onto heal with good results. She comes back at 6 months and complains of vague pain over her lateral ankle and hardware with a normal physical exam. She wonders about hardware removal, (Figs. 1 and 2). PAST MEDICAL HISTORY: - previous history of breast reduction surgery and she has delivered one child vaginally. No chronic diseases and she takes no pills except the birth control pill. SOCIAL HISTORY: - married with one child and works as an administrative assistant for a manufacturing company; she is a social drinker and nonsmoker. Has a history of using some recreational drugs but none for 10 years. She is moderately active.

Stress Tests for Deltoid Ligament and Syndesmosis Injury in Patients With Ankle Fracture: A Systemic Review With Meta-Analysis.

To determine the diagnostic accuracy of various stress tests for deltoid ligament and syndesmosis injury in patients with ankle fracture. A systemic literature search was conducted in the MEDLINE, Embase, and Cochrane Library databases to identify studies published from January 1990 to August 2022. Studies that evaluated external rotation or gravity stress tests or hook or tap tests for the diagnosis of deltoid ligament or syndesmosis injury were included. Authors, publication years, study design, index tests, reference standards, demographic features of participants, reliability, and the numbers of true-positive, true-negative, false-positive, and false-negative subjects were extracted from 14 included studies. Article quality was assessed through the revised Quality Assessment of Diagnostic Accuracy Studies tool. The pooled sensitivity and specificity of each index test for each structure were calculated with a random-effects model using the extracted data of true-positive, true-negative, false-positive, and false-negative outcomes in all relevant studies. The overall diagnostic performance of the different index tests for different structures was determined with the estimation of the area under the curve using the summary receiver operating characteristics curve. The gravity stress test and the tap test exhibited high sensitivity and specificity in diagnosing deltoid ligament injury. The hook test has relatively high accuracy in diagnosing syndesmosis injury. Further studies with large sample sizes are warranted to confirm the results of this review. Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Magnetic Resonance Imaging Characteristics of a Lateral Ligament Injury in Acute Ankle Sprains Among Athletes

Background: It is important to identify the location and pattern of lateral ligament injuries that are related to the development and prognosis of chronic ankle instability in athletes with ankle sprains. Purpose: To describe the location and pattern of lateral ligament injuries on magnetic resonance imaging (MRI) in elite-level or amateur athletes with acute ankle sprains and to further assess the risk of associated concomitant injuries. Study Design: Cross-sectional study; Level of evidence, 3. Methods: The anterior talofibular ligament (ATFL) and calcaneofibular ligament (CFL) of 110 athletes with an ankle lateral ligament injury (mean age, 24.7 years) were evaluated. MRI scans were evaluated for the location and pattern of ATFL and CFL tears such as sleeve avulsions as well as concomitant deltoid ligament injuries, bone contusions, and osteochondral lesions of the talus (OLTs). Results: On MRI, 52 (47.3%) athletes had an isolated ATFL tear, 56 (50.9%) athletes had both ATFL and CFL tears, and 2 (1.8%) athletes had an isolated CFL tear. ATFL injuries occurred at the fibula, midsubstance, and talus in approximately equal numbers, whereas the majority of CFL injuries occurred at the calcaneal insertion. Concomitant deltoid ligament injuries were identified in 18 (16.4%) athletes. In addition, concomitant bone contusions and OLTs were identified in 38 (34.5%) and 6 (5.5%) athletes, respectively. Using linear-by-linear analysis, CFL injuries correlated with concomitant deltoid ligament and bone injuries ( P = .023 and P = .001, respectively) and a sleeve injury pattern ( P = .005). Conclusion: After an acute ankle ligament rupture, almost all athletes involved in this study had injured their ATFL, and approximately 50% had a concomitant injury to the CFL. The rate of sleeve-type CFL injuries at the calcaneal insertion was high, and concomitant deltoid ligament injuries and OLTs were associated with this pattern of injury.

LOW RISK OF DELAYED TALAR SHIFT IN STABLE WEBER B FRACTURES MANAGED WITH A FUNCTIONAL BRACING PROTOCOL WITH EARLY WEIGHT BEARING

Stable Weber B fractures are typically treated non-operatively without complications but require close monitoring due to concerns over potential medial deltoid ligament injuries and the risk of delayed talar shift. Following recent evidence suggesting this is unlikely, a functional protocol with early weight bearing was introduced at Glasgow Royal Infirmary (GRI) following a pilot audit.This study aims to evaluate the risk of delayed talar shift in isolated Weber B fractures managed with functional bracing and early weight-bearing, particularly if signs of medial ligament injury are present.We conducted a retrospective review of 148 patients with isolated Weber B fractures without talar shift at presentation that were reviewed at the virtual fracture clinic at our institution between July 2019 and June 2020. The primary outcome was the incidence of delayed talar shift. Secondary outcomes were other complications and adherence to protocol.48 patients had medial signs present and of these 1 (2%) showed possible talar shift on X-rays at 4 weeks, and was kept under review. This patient had a normal medial clear space at 3 months. No patients with medial signs not documented (n=19) or not present (n=81) had delayed talar shift. 10% of patients (n=15) had at least 1 complication: delayed union (n=2); non-union (n=3); ongoing pain (n=14).Functional bracing with early weight-bearing is a safe, effective protocol for managing isolated Weber B fractures without initial talar shift. This study concludes that the risk of delayed talar shift is low in all patients, with or without medial signs.

Effect of Plate and Screw Fixation on Stability of Weber B/Supination-External Rotation Fractures with Partial Deltoid Ligament Injury (SER4a): Robotic-Based Joint Testing

Category: Trauma; Ankle Introduction/Purpose: Fibular fractures with signs of concomitant deltoid ligament injury have been operated on with plate and screw fixation of the fibula for decades. More recently, clinical studies have suggested that some fibular fractures have only partial deltoid ligament injury and that the deep posterior tibiotalar ligament may be intact (SER4a), allowing for nonoperative treatment. The purpose was to determine whether fibula fracture fixation using plate and screws improves stability and restores normal joint kinematics in such fractures. It was hypothesised that fixation of the fibula fracture does not add significantly to the stability of SER4a models or restore normal joint kinematics. Methods: Fifteen cadaveric foot and ankle specimens underwent biomechanical testing using a six-degrees-of-freedom force- movement robotic arm in three states: intact joint, SER4a model (anterior inferior tibiofibular ligament sectioned + oblique trans syndesmotic fibular osteotomy + superficial layer of deltoid ligament sectioned + deep anterior tibiotalar ligament sectioned) and SER4a model + plate and screw fixation of the fibula. Joint stability was measured in lateral translation, valgus, and talar internal- and external rotation in three talocrural joint positions: 20° plantarflexion, neutral, and 10° dorsiflexion. Fluoroscopy was used to measure isolated talar lateralisation and talar tilt. The foot was rigidly fixed to a custom pedestal, while the tibia was rigidly fixed to the robot arm through a load cell. Talar lateral translation at neutral ankle position was the primary outcome. Results: Fixation of the fibular fracture reduced lateral translation by 0.16 millimetres (P = .101) at neutral ankle position (See Figure 1). In general, the tests for lateral translation and valgus showed no differences between the SER4a models and the SER4a models with fibular fracture fixation. As for talar internal rotation, the fixation only slightly increased stability. But, when the talus was externally rotated, the fixation provided stability. Although the fixation improved stability during rotations, it did not fully restore the native ankle kinematics. Conclusion: The results suggest that plate and screw fixation of the fibular fracture does not significantly reduce instability or restore intact joint stability in SER4a models. These results support the nonoperative treatment of these fractures, as suggested by previous clinical studies.

Hindfoot Stability Test: Introduction and Validation of a Diagnostic Test of Subtalar Instability in Deltoid Ligament injury Associated with Ankle Fractures

Category: Ankle; Trauma Introduction/ Purpose: Deltoid ligament complex (DLC) injury repair in the presence of an ankle fracture remains a topic of controversy in the current literature. No work in the current literature has commented on hindfoot and subtalar instability in the presence DLC injury associated with ankle fracture fixation. Objective Our aim was to introduce and validate a new method for assessment of hindfoot instability, when fixing an ankle fracture with associated DLC injury. Methods: DLC injury, specifically superficial DLC, controls not only the ankle but the subtalar joint and medial longitudinal arch. Valgus stressing can unmask subtalar instability. It was noted by referencing the hindfoot position to a line parallel with the lateral aspect of the fibula, the lateral fibula line, subtalar instability was proabbale. We used six morphologically normal cadaveric specimens to validate the test. Results: Ten cadaveric specimens were used for validation of the hindfoot stability test. Pre-injury, no specimen illustrated bisection5-injury, all specimens showed bisection of the calcaneal tuberosity by the lateral fibular line on hindfoot stability test. Conclusion: The hindfoot stability test assesses hindfoot stability on valgus stressing of the hindfoot using the calcaneal tuberosity bisection of the a line drawn from the lateral border of the fibula as a reference point for instability. This was validated using morphologically normal cadavers.

Bone marrow edema at ligament insertion is an accurate MRI sign of deltoid ligament injury.

Magnetic resonance imaging (MRI) is effective in diagnosing deltoid ligament (DL) injury but its sensitivity in chronic cases is low. Additional diagnostic signs are required to reduce the risk of a false negative diagnosis. To evaluate the added diagnostic value of bone marrow edema at the ligament insertion (BMELI) of DL to the MRI assessment of chronic DL injury. One hundred patients who consecutively came to our institution between November 2018 and December 2021 and underwent arthroscopic surgery for chronic ankle instability (CAI) were enrolled in the present study. Preoperative MR images were retrospectively reviewed by two orthopedic surgeons to evaluate the sensitivity, specificity and interobserver reliability of three MRI signs in diagnosing chronic DL injury, namely, abnormal ligamentous morphological characteristics (ALMC), BMELI and medial clear space (MCS). Taking arthroscopy as the reference standard, there were 34 patients with and 66 without DL injury. ALMC had 64.71% (22/34; 46.47-79.70) sensitivity and 83.33% (55/66; 71.71-91.00) specificity, BMELI had 70.59% (24/34; 52.33-84.29) sensitivity and 95.45% (63/66; 86.44-98.82) specificity and MCS had 26.47% (9/34; 13.51-44.65) sensitivity and 92.42% (61/66; 82.50-97.18) specificity. Compared with ALMC, BMELI had similar efficacy in superficial cases (P = 0.06) and greater efficacy in deep cases (P = 0.04). All three signs showed good interobserver agreement (kappa values all above 0.7). BMELI can reliably indicate concomitant injury to the DL in CAI patients. Using BMELI as a sign of chronic DL injury when ALMC is unclear may reduce the risk of a false negative diagnosis.

702 Hindfoot Stability Test - Introduction and Validation of a Diagnostic Test of Subtalar Instability in Deltoid Ligament Injury Associated with Ankle Fractures

Abstract Aim Deltoid ligament complex (DLC) injury repair in the presence of an ankle fracture remains a topic of controversy in the current literature. No work in the current literature has commented on hindfoot and subtalar instability in the presence DLC injury associated with ankle fracture fixation. Our aim was to introduce and validate a new method for assessment of hindfoot instability, when fixing an ankle fracture with associated DLC injury. Method DLC injury, specifically superficial DLC, controls not only the ankle but the subtalar joint and medial longitudinal arch. Valgus stressing can unmask subtalar instability. It was noted by referencing the hindfoot position to a line parallel with the lateral aspect of the fibula, the lateral fibula line, subtalar instability was probable. We used six morphologically normal cadaveric specimens to validate the test. Results Six cadaveric specimens were used for validation of the hindfoot stability test. Pre-injury, no specimen illustrated bisection of the calcaneal tuberosity by the lateral fibular line on hindfoot stability test under fluoroscopy. Post-injury, all specimens showed bisection of the calcaneal tuberosity by the lateral fibular line on hindfoot stability test. Conclusions The hindfoot stability test assesses hindfoot stability on valgus stressing of the hindfoot using the calcaneal tuberosity bisection of a line drawn from the lateral border of the fibula as a reference point for instability. This was validated using morphologically normal cadavers.

Effects of Progressive Deltoid Ligament Sectioning on Weber B Ankle Fracture Stability.

Conventionally, transsyndesmotic fibula fractures with concomitant signs of deltoid ligament injury have been considered unstable and thus treated operatively. Recent studies have indicated that partial deltoid ligament rupture is common and may allow for nonoperative treatment of stress-unstable ankles if normal tibiotalar alignment is obtained in the weightbearing position. Biomechanical support for this principle is scarce. The purpose of this study was to evaluate the biomechanical effects of gradually increasing deltoid ligament injury in transsyndesmotic fibula fractures. Fifteen cadaveric ankle specimens were tested using an industrial robot. All specimens were tested in 4 states: native, SER2, SER4a, and SER4b models. Ankle stability was measured in lateral translation, valgus, and internal and external rotation stress in 3 talocrural joint positions: 20 degrees plantarflexion, neutral, and 10 degrees dorsiflexion. Talar shift and talar valgus tilt in the talocrural joint was measured using fluoroscopy. In most tests, SER2 and SER4a models resulted in a small instability increase compared to native joints and thus were deemed stable according to our predefined margins. However, SER4a models were unstable when tested in the plantarflexed position and for external rotation in all positions. In contrast, SER4b models had large-magnitude instability in all directions and all tested positions and were thus deemed unstable. This study demonstrated substantial increases in instability between the SER4a and SER4b states. This controlled cadaveric simulation suggests a significant ankle-stabilizing role of the deep posterior deltoid after oblique transsyndesmotic fibular fracture and transection of the superficial and anterior deep deltoid ligaments. The study provides new insights into how the heterogenicity of deltoid ligament injuries can affect the natural stability of the ankle after Weber B fractures. These findings may be useful in developing more targeted and better treatment strategies.

The Biomechanical Role of the Deltoid Ligament on Ankle Stability: Injury, Repair, and Augmentation

Background: Deltoid ligament injuries occur in isolation as well as with ankle fractures and other ligament injuries. Both operative treatment and nonoperative treatment are used, but debate on optimal treatment continues. Likewise, the best method of surgical repair of the deltoid ligament remains unclear. Purpose: To determine the biomechanical role of native anterior and posterior components of the deltoid ligament in ankle stability and to determine the efficacy of simple suture versus augmented repair. Study Design: Controlled laboratory study. Methods: Ten cadaveric ankles (mean age, 51 years; age range, 34-64 years; all male specimens) were mounted on a 6 degrees of freedom robotic arm. Each specimen underwent biomechanical testing in 8 states: (1) intact, (2) anterior deltoid cut, (3) anterior repair, (4) tibiocalcaneal augmentation, (5) deep anterior tibiotalar augmentation, (6) posterior deltoid cut, (7) posterior repair, and (8) complete deltoid cut. Testing consisted of anterior drawer, eversion, and external rotation (ER), each performed at neutral and 25° of plantarflexion. A 1-factor, random-intercepts, linear mixed-effect model was created, and all pairwise comparisons were made between testing states. Results: Cutting the anterior deltoid introduced ER (+2.1°; P = .009) and eversion laxity (+6.2° of eversion; P < .001) at 25 degrees of plantarflexion. Anterior deltoid repair restored native ER but not eversion. Tibiocalcaneal augmentation reduced eversion laxity, but tibiotalar augmentation provided no additional benefit. The posterior deltoid tear showed no increase in laxity. Complete tear introduced significant anterior translation, ER, and eversion laxity (+7.6 mm of anterior translation, +13.8° ER and +33.6° of eversion; P < .001). Conclusion: A complete deltoid tear caused severe instability of the ankle joint. Augmented anterior repair was sufficient to stabilize the complete tear, and no additional benefit was provided by posterior repair. For isolated anterior tear, repair with tibiocalcaneal augmentation was the optimal treatment. Clinical Relevance: Deltoid repair with augmentation may reduce or avoid the need for prolonged postoperative immobilization and encourage accelerated rehabilitation, preventing stiffness and promoting earlier return to preinjury activity.