The evaluation of rotational lateral ankle laxity in gravity stress position by ultrasonography: normative value in uninjured ankles.

BACKGROUND: The evaluation of lateral ankle laxity remains challenging when diagnosing chronic lateral ankle instability (CLAI). Several studies have reported that internal rotation of the talus as an indicator of rotational lateral ankle laxity (RLAL) increases in patients with CLAI. However, there is no established method for detecting and evaluating the RLAL. This study aimed to report a novel method for evaluating the RLAL in the gravity stress position by measuring the talofibular distance (TFD) using ultrasonography (US) and show the normative value of the TFD. METHODS: The TFDs in the subjects with healthy ankles were prospectively measured 10 mm distal to the ankle joint in the neutral ankle position and gravity stress position using US. The differences in the TFD between the two ankle positions were evaluated. The differences in the TFD by gender and ankle laterality were also evaluated. RESULTS: A total of 52 healthy ankles of 28 subjects (mean age, 24.0 ± 1.6; male/female, 12/16) were finally included. There was a significant difference in the TFD between the neutral ankle position (6.9 ± 0.9 mm) and gravity stress position (9.0 ± 0.9 mm) (p < 0.001). The mean difference in the TFD between the two ankle positions was 2.1 ± 0.6 mm. There were no significant differences in the TFD by gender and ankle laterality. CONCLUSIONS: The present study reported a novel US method for evaluating RLAL by applying gravity stress and the normative value of the TFD.

Quantitative assessment of anterior talofibular ligament quality in chronic lateral ankle instability using magnetic resonance imaging T2* value.

OBJECTIVE: To determine T2* normal reference values for anterior talofibular ligament (ATFL) and to investigate the feasibility of the quantitative ATFL quality evaluation in chronic lateral ankle instability (CLAI) using T2* values. MATERIALS AND METHODS: This study enrolled 15 patients with CLAI and 30 healthy volunteers. The entire ATFL T2* values from the MRI T2* mapping were measured. The prediction equation (variables: age, height, and weight) in a multiple linear regression model was used to calculate the T2* normal reference value in the healthy group. T2* ratio was defined as the ratio of the actual T2* value of the patient's ATFL to the normal reference value for each patient. A Telos device was used to measure the talar tilt angle (TTA) from the stress radiograph. RESULTS: T2* values of ATFL in the healthy and CLAI groups were 10.82 ± 1.84 ms and 14.36 ± 4.30 ms, respectively, which are significantly higher in the CLAI group (P < 0.05). The prediction equation of the normal reference T2* value was [14.9 + 0.14 × age (years) - 4.7 × height (m) - 0.03 × weight (kg)] (R2 = 0.65, P < 0.0001). A significant positive correlation was found between the T2* ratio and TTA (r = 0.66, P = 0.007). CONCLUSION: MRI T2* values in patients with CLAI were higher than those in healthy participants, and the T2* ratio correlated with TTA, suggesting that T2* values are promising for quantitative assessment of ATFL quality preoperatively.

Variability in sonographic anterior drawer test measurements of the ankle: Experienced versus beginner examiners.

BACKGROUND: This study aimed to clarify the variability in the measurements of stress sonography of the ankle and determine the effects of examiner experience on the measurements. METHODS: Twenty examiners (10 experienced and 10 beginners) were included in the study. Each examiner performed stress ultrasonography on a patient with a chronic anterior talofibular ligament injury and a patient with an intact ligament using the reverse anterior drawer method. Changes in ligament length before versus after stress were determined. The same 20 examiners performed ultrasonography on two other patients with an injured or intact ATFL using the anterior drawer method. The length change values and variance were compared between the groups using t-tests and F-tests. RESULTS: Using the reverse anterior drawer method, the change in the anterior talofibular ligament length was 3.3 mm (range, 2.2-4.8 mm) in the experienced group and 2.7 mm (0.0-4.1 mm) in the beginner group for the ligament injured patient. The length changes for the patient with intact anterior talofibular ligament were 0.5 mm (0.1-0.9 mm) and 0.4 mm (-0.1-1.5 mm) in the experienced and beginner groups, respectively. There were no significant intergroup differences in measurement amount (P = 0.37) or variance (P = 0.72). Similarly, using the anterior drawer method, no significant differences between the groups were found in measurement amount or variance. CONCLUSION: The quantitative evaluation of stress sonography of the ankle was variable regardless of examiner experience or stress method, particularly in patients with an anterior talofibular ligament injury. The amount of variability appeared to be unacceptably large for clinical application. Our study results highlight the need for technical standardization.

The calcaneofibular ligament groove at the inferior fibula, an ultrasonographic anatomical landmark.

PURPOSE: Calcaneofibular ligament (CFL) injuries are harder to diagnose than anterior talofibular ligament (ATFL) ones. This study aimed to clarify the fibular attachment of the CFL and verify the bony landmark for evaluating the CFL on ultrasonography. METHODS: Fifty-nine ankles were used in this anatomical study. To confirm the control function of the CFL, we performed passive movement manually using cadaveric ankles and observed the ankle positions where the CFLs were tense. Histological observation of CFL attachment of the fibula was performed using Masson's trichrome stain. The ATFL and CFL were removed, and the bone morphology of the CFL attachment and inferior fibular end was imaged using a stereomicroscope and a 3D scanner. Using ultrasonography, we evaluated the bone morphology of the fibular attachment of the CFL in short-axis images of 27 healthy adult ankles. RESULTS: The CFL was tensed according to ankle motions: supination, maximum dorsi flexion, maximum plantar flexion, and mild plantar flexion-external rotation. Below the CFL attachment of the fibula was a slight groove between the inferior tip and the obscure tubercle of the fibula. This groove was observed in 81.5% of cases using short-axis ultrasonography. CONCLUSION: The CFL was tensed in various ankle positions to control the movements of the talocrural and subtalar joints. There was a slight groove at the inferior end of the fibula where the CFL coursed downward. We called it the CFL groove and proposed that it could serve as a landmark for the short-axis image of ultrasonography.

Postoperative Magnetic Resonance Evaluation of Anterior Talofibular Ligament Following Arthroscopic Brostrom Procedure: Analysis and Outcomes of 40 Repairs at 12 Months.

Lateral ankle sprains are one of the most common orthopedic injuries. When conservative treatment fails, surgical correction is often performed using either open or arthroscopic techniques. We hypothesize that MRI evaluation of the arthroscopic brostrom repair will show intact repair and decrease in thickness of the anterior talofibular ligament (ATFL) at 1 year, with statistically significant improvement of patient function and pain scores. Postoperative MRI was utilized at minimum 1-year follow-up to evaluate the integrity of the arthroscopic brostrom repair, as well as comparison of ATFL thickness to literature validated average thickness. A musculoskeletal fellowship trained radiologist performed all MRI reads. In addition, 3 fellowship trained foot and ankle specialists from a single institution all performed measurements of the ATFL. Surgical satisfaction using 1 to 100 scale, and Karlsson-Peterson (KP) were measured at 1 year postoperatively. In addition, pre- and postoperative Foot Function Index (FFI), American Orthopedic Foot and Ankle (AOFAS) hindfoot scores, and Visual Analog Scale (VAS) were measured using unpaired t tests. All repairs were shown to be intact at minimum 1-year follow-up via MRI evaluation, with ATFL thickness of 2.21 mm. Preoperative FFI, AOFAS, and VAS were 54.9, 46.4, and 7.1 respectively. Postoperative scores were 11.0, 91.7, and 1.3 respectively. Surgical satisfaction was 88.2, KP was 75.3. Comparison of pre- and postoperative scores (VAS, FFI, AOFAS) were shown to be statistically significant, p < .05. No significant difference in demographic data was observed at 1 year. The data from this study offers evidence that the arthroscopic brostrom repair provides patients with good outcomes as well as an intact ATFL with normal morphology at 1 year postoperatively.

Diagnostic value of ultrasonography for injury of anterior talofibular ligament and anterior inferior tibiofibular ligament distal fascicle in patients with ankle fractures. / è¶ å£°è¯„ä¼°è¸å ³èŠ‚éª¨æŠ˜æ‚£è€ è·è “å‰éŸ§å¸¦åŠä¸‹èƒ«è “å‰éŸ§å¸¦è¿œä¾§æŸæŸä¼¤çš„ä»·å€¼.

OBJECTIVES: To explore the diagnostic value of ultrasonography for injuries of anterior talofibular ligament (ATFL) and anterior inferior tibiofibular ligament distal fascicle (ATiFL-DF) in patients with ankle fractures. METHODS: Clinical data of 51 patients with ankle fractures who were clinically suspected of ligament injuries and underwent ankle ultrasonography examination and arthroscopy in Sir Run Run Shaw Hospital, Zhejiang University School of Medicine from April 2019 to March 2023 were retrospectively analyzed. Using arthroscopic results as the gold standard, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of ultrasonography in diagnosing ATFL and ATiFL-DF injuries were evaluated, and Kappa consistency test was performed. RESULTS: The sensitivity and specificity of ultrasonography in diagnosis of ATFL injury were 100.0% and 92.3%, with the PPV of 92.6% and NPV of 100.0%. Ultrasonography findings exhibited excellent concordance with arthroscopic results (kappa=0.849). The sensitivity and specificity of ultrasonography in diagnosis of ATiFL-DF injury was 86.7% and 33.3%, with the PPV of 90.7% and NPV of 25.0%. However, the consistency between ultrasonography and arthroscopic results was poor (kappa=0.168). CONCLUSIONS: Ultrasonography is reliable in assessing injuries of ATFL in patients with ankle fractures, but its specificity in diagnosing ATiFL-DF is poor. Therefore, ankle arthroscopy remains necessary for ankle fracture patients with negative findings of ATiFL-DF in ultrasonography.

Imaging diagnosis for anterior talofibular ligament injury: a systemic review with meta-analysis.

A definite diagnosis of ankle ligament injury is crucial, and many imaging examinations can be used. This review systematically analyzed the effectiveness of various examination methods in the diagnosis of anterior talofibular ligament (ATFL) injuries. Three English databases (PubMed, Embase, and Cochrane Library) and three Chinese databases (CNKI, VIP Database, and Wanfang Database) were searched and relevant studies were summarized. A total of 25 randomized controlled trials met the selection criteria, including six, 16, and three studies recruiting patients with acute, chronic, and both acute and chronic ATFL injuries, respectively. A total of 1409 participants were included. The pooled sensitivity rates of acute ATFL injuries were 82.1% (77.1%-86.5%) by magnetic resonance imaging (MRI) and 88.6% (82.0%-93.5%) by ultrasonography (US). The pooled sensitivity rates of chronic ATFL injuries were 86.3% (82.5%-89.5%) by MRI, 98.7% (95.3%-99.8%) by US, 74.4% (63.6%-83.4%) by stress radiography, and 100% (87.7%-100.0%) for MR arthrography. The pooled specificity rates of acute ATFL injuries were 37.8% (29.1%-47.2%) by MRI and 90.3% (80.1%-96.4%) by US. The pooled specificity rates of chronic ATFL injuries were 86.8% (81.3%-91.2%) by MRI, 94.0% (85.4%-98.3%) for US, 89.4% (76.9%- 96.5%) by stress radiography and 100% (54.1%-100.0%) by MR arthrography. In conclusion, US may be a valuable imaging technique with high sensitivity for diagnosing chronic lateral ankle ligament injuries.

The lowest point of fibula (LPF) could be used as a reliable bony landmark for arthroscopic anchor placement of lateral ankle ligaments ----compared with open Broström procedure.

BACKGROUND: Arthroscopic technique procedures was wide accepted for the treatment of chronic ankle instability (CAI). But little acknowledge was involved to the bony landmarks and anatomic features of different bundles of lateral ligaments under arthroscopic view. METHODS: Sixty patients with acute or chronic lateral ankle ligaments injury (LAI) were collected prospectively, and divided randomly into two groups. In arthroscopic group, the bone tunnels were made on the LPF arthroscopically. And in open group, the bone tunnels were made on the Fibular obscure tubercle (FOT) in open procedure. The inferior bundle of ATFL and Arcuate fibre was also identified reference to the LPF and labeled by a PDS II suture penetration. Following that, The distances of the bone tunnels to the different bony markers were measured and compare between two groups. The penetrating locations of PDS II on the inferior bundle of ATFL and Arcuate fibre were also confirmed intraoperatively. And the safe angle of anchor implantation on the axial view was measured on postoperative CT scan. RESULTS: The distances of bone tunnel to the fibular tip, the fibular insertion of anterior-inferior tibiofibular ligament (AITFL), and the FOT in arthroscopic and open locating groups were 4.9 ± 2.2 and 6.3 ± 2.2 mm, 13.5 ± 2.7 and 12.4 ± 1.1 mm, 5.8 ± 2.2 and 5.6 ± 1.0 mm, respectively. The distances of bone tunnels to the FOT and fibular tip on 3d-CT view was 4.4 ± 1.5 and 4.6 ± 0.9 mm, 14.4 ± 3.2 and 13.2 ± 1.8 mm in arthroscopic and open group, and there were no significant differences between two groups. The safe angle of arthroscopic anchor placement on the axial plan was ranged from 24.9 ± 6.3o to 58.1 ± 8.0o. The PDS II sutures penetrating on the inferior bundles of ATFL and the arciform fibres were also comfirmed successfully by open visualizaion.The average distance of penetration point to the horizontal line cross the fibular tip was 2.3 ± 2.7 mm (ranged from - 3.1 to 6.0 mm), and to the vertical line cross the FOT was 2.7 ± 2.7 mm (ranged from - 2.5 to 7.5 mm). CONCLUSION: Take the lowest point of fibula under arthroscopy (LPF) as a bony reference, we could identify the iATFL under arthroscopic visualization. By this way, we could place the suture anchors properly to the fibular footprint and suture the iATFL fibres successfully.

Use of a comprehensive systemic ultrasound evaluation in the diagnosis and analysis of acute lateral region ankle sprain.

BACKGROUND: For the diagnosis of acute lateral ankle sprain, many clinicians use ultrasound; they typically focus on the lateral ligament complex, which is the most common site of lesions in ankle sprain. However, this approach risks missing other foot and ankle lesions. The present study aimed to provide and analyze the results of a new ultrasound method of diagnosis for acute lateral ankle sprain which can thoroughly investigate overall lesions of the foot and ankle. METHODS: Retrospective cross-sectional cohort study of 123 patients who underwent diagnostic ultrasound within 1 week of acute lateral ankle injury was performed. Causes of ankle sprain, incidence and severity of each ligament injury, location of anterior talofibular ligament (ATFL) injury, accompanying ligament injury, and occult fracture were analyzed. RESULTS: Among the 102 cases of ATFL injuries, 60 (58.5%) had islolated ATFL injury, 28 (27.5%) had accompanying calcaneofibular ligament injury (CFL), and 14 (13.7%) had accompanying midtarsal or syndesmosis injury. ATFL injuries occurred on the fibula attachment in 48 (47.1%) cases, ligament mid-substance in 24 (23.5%) cases, and talus attachment in 30 (29.4%) cases. Among the 165 lesions from 123 cases, injuries of the fourth or fifth dorsal tarsometatarsal (12 cases, 7.3%), bifurcate (11 cases, 6.7%), and anterior tibiofibular (11 cases, 6.7%) ligaments were not rare. CONCLUSION: These findings suggest that an ultrasound examination involving investigation of the midtarsal joint and syndesmotic ligament, as well as the ATFL and CFL, is useful for comprehensive, systemic diagnosis of acute lateral ankle sprain.

Evaluation of chronic ankle instability and subtalar instability using the angle between the anterior talofibular ligament and calcaneofibular ligament.

PURPOSE: A series of studies have reported a change in the length or thickness of the anterior talofibular (ATFL) and calcaneofibular (CFL) ligaments in patients with chronic ankle instability. However, no study has examined the changes in the angle between the ATFL and CFL in patients diagnosed with chronic ankle instability. Therefore, this study analyzed the change in the angle between the ATFL and CFL in patients diagnosed with chronic ankle instability to confirm its relevance. METHODS: This retrospective study included 60 patients who had undergone surgery for chronic ankle instability. Stress radiographs comprising the anterior drawer test, varus stress test, Broden's view stress test, and magnetic resonance imaging (MRI) were performed in all patients. The angle between the ATFL and CFL was measured by indicating the vector at the attachment site, as seen on the sagittal plane. Three groups were classified according to the angle between the two ligaments measured by MRI: group I when the angle was > 90°, Group II when the angle was 71-90°, and Group III when the angle was ≤ 70°. The accompanying injuries to the subtalar joint ligament were analyzed via MRI. RESULTS: A comparison of the angles between the ATFL and CFL measured on MRI in Group I, Group II, and Group III with the angles measured in the operating room revealed a significant correlation. Broden's view stress test revealed a statistically significant difference among the three groups (p < 0.05). The accompanying subtalar joint ligament injuries differed significantly among the three groups (p < 0.05). CONCLUSION: The ATFL-CFL angle in patients with ankle instability is smaller than the average angle in ordinary people. Therefore, the ATFL-CFL angle might be a reliable and representative measurement tool to assess chronic ankle instability, and subtalar joint instability should be considered if the ATFL-CFL angle is 70° or less. LEVEL OF EVIDENCE: Level III.

Computer-Aided Ankle Ligament Injury Diagnosis from Magnetic Resonance Images Using Machine Learning Techniques.

Ankle injuries caused by the Anterior Talofibular Ligament (ATFL) are the most common type of injury. Thus, finding new ways to analyze these injuries through novel technologies is critical for assisting medical diagnosis and, as a result, reducing the subjectivity of this process. As a result, the purpose of this study is to compare the ability of specialists to diagnose lateral tibial tuberosity advancement (LTTA) injury using computer vision analysis on magnetic resonance imaging (MRI). The experiments were carried out on a database obtained from the Vue PACS-Carestream software, which contained 132 images of ATFL and normal (healthy) ankles. Because there were only a few images, image augmentation techniques was used to increase the number of images in the database. Following that, various feature extraction algorithms (GLCM, LBP, and HU invariant moments) and classifiers such as Multi-Layer Perceptron (MLP), Support Vector Machine (SVM), k-Nearest Neighbors (kNN), and Random Forest (RF) were used. Based on the results from this analysis, for cases that lack clear morphologies, the method delivers a hit rate of 85.03% with an increase of 22% over the human expert-based analysis.

MRI signal intensity ratio reflects the quality of the anterior talofibular and calcaneofibular ligaments in patients with chronic lateral ankle instability.

BACKGROUND: Ligament quality can affect clinical outcomes of ligament repair in chronic lateral ankle instability (CLAI). Magnetic resonance imaging (MRI) is used to assess the morphological changes of ligaments, but the measurement of signal intensity enables quantitative evaluation, which can evaluate the degree of the ligament quality. This study aimed to evaluate the qualitative diagnostic capacity for anterior talofibular ligament (ATFL) and calcaneofibular ligament (CFL) injuries of the signal intensity on MRI. METHODS: Thirty-eight and 20 ankles with and without CLAI, respectively, were included. The regions of interest (ROIs) were set in the ATFL, CFL, and tibialis anterior tendon (TAT) on MRI, and the signal intensities were measured. The signal intensities of the ATFL and CFL were corrected using TAT as the signal intensity ratio (SIR). The SIRs of the ATFL and CFL in the control and CLAI groups were compared. The relationship between the SIR of the ATFL and the arthroscopic findings was analyzed. Finally, the SIRs of the CFL in CLAI with and without CFL repair were compared. RESULTS: The mean SIR of the ATFL in the CLAI group (6.1 ± 2.4) was significantly higher than that in the control (2.1 ± 0.4) (P < 0.01). The SIR of the ATFL was associated with the arthroscopic grading. The mean SIR of the CFL in the CLAI groups (4.1 ± 2.5) was significantly higher than that in the control (1.7 ± 0.4) (P < 0.01). The SIR of the CFL in patients with the requirement of the CFL repair (6.2 ± 1.9) was significantly higher than that without the CFL repair (2.1 ± 0.5) (P < 0.05). CONCLUSIONS: The SIR is useful for evaluating the quality of the ATFL and CFL, which enables the decision of the treatment strategy of the CLAI.

Modified classifications and surgical decision-making process for chronic anterior talofibular ligament injuries based on the correlation of imaging studies and arthroscopic findings.

PURPOSE: Surgical treatment of chronic ankle instability (CAI) typically includes ligament repair or reconstruction. Using preoperative ultrasonography or magnetic resonance imaging (MRI) to choose an appropriate arthroscopic procedure is still difficult. The aim of this study was to evaluate the correlation of imaging studies with arthroscopic findings and support the arthroscopic surgical decision-making process. METHODS: One hundred twelve patients with chronic anterior talofibular ligament (ATFL) injuries were treated using the arthroscopic surgical decision-making process from November 2018 to August 2020. Preoperative imaging assessments using dynamic ultrasonography, MRI, and combined methods were applied to categorize the ATFL remnants into three quality grades ("good," "fair," and "poor"). Arthroscopic findings were classified into 6 major types (7 subtypes) and used to select an appropriate surgical procedure. Correlations between imaging studies, arthroscopic findings, and surgical methods were evaluated. Diagnostic parameters, clinical outcomes, and complications were also assessed. RESULTS: There was a significant interobserver agreement in the evaluation of dynamic ultrasonography (0.954, P < 0.001), MRI (0.958, P < 0.001), and arthroscopy diagnosis (0.978, P < 0.001). There was a significant correlation between the modified imaging classifications, arthroscopic diagnostic types, and surgical procedures. The mean follow-up period was 33.58 ± 8.85 months. Significant improvements were documented in postoperative ankle functions when assessed with Karlson-Peterson scores and Cumberland Ankle Instability Tool scores. The risk of complications is also very low. CONCLUSION: The modified classifications and surgical decision-making process based on dynamic ultrasonography, MRI, and arthroscopic findings, as proposed in this study, might help in selecting an appropriate arthroscopic surgical procedure for chronic ATFL injuries.

The increased anterior talofibular ligament-posterior talofibular ligament angle on MRI may help evaluate chronic ankle instability.

PURPOSE: This study intended to compare the difference between the anterior talofibular ligament (ATFL) and posterior talofibular ligament (PTFL) angle with chronic ankle instability (CAI) patients and healthy volunteers, and to confirm whether using the ATFL-PTFL angle could be a reliable assessment method for CAI, so as to improve the accuracy and specificity of clinical diagnosis. METHODS: This retrospective study included 240 participants: 120 CAI patients and 120 healthy volunteers between 2015 and 2021. The ATFL-PTFL angle of the ankle region was gaged in the cross-sectional supine position on MRI between two groups. After participants undergoing a comprehensive MRI scanning, ATFL-PTFL angles were regarded as the main indicator of patients with the injured ATFLs and healthy volunteers to compare, and were measured by an experienced musculoskeletal radiologist. Moreover, other qualitative and quantitative indicators referring to anatomical and morphological characteristics of the AFTL were included in this study with MRI, such as the length, width, thickness, shape, continuity, and signal intensity of the ATFL, which can be used as secondary indicators. RESULTS: In the CAI group, the ATFL-PTFL angle was 90.8° ± 5.7°, which was significantly different from the non-CAI group where the ATFL-PTFL angle for 80.0° ± 3.7° (p < 0.001). As for the ATFL-MRI characteristics, the length (p = 0.003), width (p < 0.001), and thickness (p < 0.001) in the CAI group were also significantly different from the non-CAI group. Over 90% of the cases, patients of the CAI group had injured ATFL with an irregular shape, non-continuous, and high or mixed signal intensity. CONCLUSION: Compared with healthy people, the ATFL-PTFL angle of most CAI patients is larger, which can be used as a secondary index to diagnose CAI. However, the MRI characteristic changes of ATFL may not relate to the increased ATFL-PTFL angle.

Accuracy of radiographic techniques in detection of the calcaneofibular ligament calcaneal insertion for lateral ankle ligament complex surgery.

BACKGROUND: Grade III ankle sprains that fail conservative treatment can require surgical management. Anatomic procedures have been shown to properly restore joint mechanics, and precise localization of insertion sites of the lateral ankle complex ligaments can be determined through radiographic techniques. Ideally, radiographic techniques that are easily reproducible intraoperatively will lead to a consistently well-placed CFL reconstruction in lateral ankle ligament surgery. PURPOSE: To determine the most accurate method to locate the calcaneofibular ligament (CFL) insertion radiographically. METHODS: MRIs of 25 ankles were utilized to identify the "true" insertion of the CFL. Distances between the true insertion and three bony landmarks were measured. Three proposed methods (Best, Lopes, and Taser) for determining the CFL insertion were applied to lateral ankle radiographs. X and Y coordinate distances were measured from the insertion found on each proposed method to the three bony landmarks: the most superior point of the postero-superior surface of the calcaneus, the posterior most aspect of the sinus tarsi, and the distal tip of the fibula. X and Y distances were compared to the true insertion found on MRI. All measurements were made using a picture archiving and communication system. The average, standard deviation, minimum, and maximum were obtained. Statistical analysis was performed using repeated measures ANOVA, and a post hoc analysis was performed with the Bonferroni test. RESULTS: The Best and Taser techniques were found to be closest to the true CFL insertion when combining X and Y distances. For distance in the X direction, there was no significant difference between techniques (P = 0.264). For distance in the Y direction, there was a significant difference between techniques (P = 0.015). For distance in the combined XY direction, there was a significant difference between techniques (P = 0.001). The CFL insertion as determined by the Best method was significantly closer to the true insertion compared to the Lopes method in the Y (P = 0.042) and XY (P = 0.004) directions. The CFL insertion as determined by the Taser method was significantly closer to the true insertion compared to the Lopes method in the XY direction (P = 0.017). There was no significant difference between the Best and Taser methods. CONCLUSION: If the Best and Taser techniques can be readily used in the operating room, they would likely prove the most reliable for finding the true CFL insertion.

Advantages of ultrasound identification of the distal insertion of the calcaneofibular ligament during ligament reconstructions.

INTRODUCTION: In lateral ankle instability, anatomical ligament reconstructions are generally performed using arthroscopy. The ligament graft is passed through the talar, fibular and calcaneal tunnels, reconstructing the anterior talofibular and calcaneofibular (CFL) bundles. However, the calcaneal insertion of the CFL needs to be performed in an extra-articular fashion, and cannot be carried out under arthroscopy, thus requiring specific anatomical landmarks. For obtaining these landmarks, methods based on radiography or surface anatomy have already been described but can only offer an approximate identification of the actual CFL anatomical insertion point. In contrast, an ultrasound technique allows direct visualization of the insertion point and of the sural nerve that may be injured during surgery. Our study aimed to assess the reliability and accuracy of ultrasound visualization when performing calcaneal insertion of the CFL with specific monitoring of the sural nerve. MATERIALS AND METHODS: Our anatomical study was carried out on 15 ankles available from a body donation program. Ultrasound identification of the sural nerve was obtained first with injection of dye. A needle was positioned at the level of the calcaneal insertion of the CFL. After dissection, in all the ankles, the dye was in contact with the sural nerve and the needle was located in the calcaneal insertion area of the CFL. The mean distance between the sural nerve and the needle was 4.8 mm (range 3-7 mm). DISCUSSION AND CONCLUSION: A pre- or intra-operative ultrasound technique is a simple and reliable means for obtaining anatomical landmarks when drilling the calcaneal tunnel for ligament reconstruction of the lateral plane of the ankle. This tunnel should preferably be drilled obliquely from the heel towards the subtalar joint (1 h-3 h direction on an ultrasound cross section), which preserves a maximum distance from the sural nerve for safety purposes, while allowing an accurate anatomical positioning of the osseous tunnel.

Determining the Feasibility of Arthroscopic Anterior Talofibular Ligament Repair Utilizing a Novel Classification System.

The purposes of this study were to classify anterior talofibular ligament injuries (ATFL), to find out the feasibility of arthroscopic ATFL repair according to injury type and to investigate the diagnostic validity of magnetic resonance imaging (MRI) of ATFL injuries by comparing MRI and arthroscopic findings. The 197 ankles (93 right, 104 left, and 12 bilateral) of 185 patients (90 men and 107 women; mean age, 33.5 years, range: 15-68 years) were treated by arthroscopic modified Broström procedure after a diagnosis of chronic lateral ankle instability. ATFL injuries were classified according to their grade and location (type P: partial rupture, type C1: fibular detachment, type C2: talar detachment, type C3: midsubstance rupture, type C4: absence of ATFL, type C5: os subfibulare). Among the 197 injured ankles, according to ankle arthroscopy, 67 were type P (34%), 28 were type C1 (14%), 13 were type C2 (7%), 29 were type C3 (15%), 26 were type C4 (13%), and 34 were type C5 (17%). The kappa value for the agreement between the arthroscopic findings and MRI findings was also high (0.85; 95% confidence interval, 0.79-0.91). Our results also supported the use of MRI for diagnosing ATFL injuries and showed that it is an informative tool during the preoperative period.

Acute Distal Rupture of the Calcaneus-Fibular Ligament Near the Calcaneus Insertion: Magnetic Resonance Imaging for Diagnostic Value and Comparison to Surgical Findings-A Retrospective Case Series Study.

Distal rupture of the calcaneus-fibular ligament (CFL) was unique and important, because it is crucial to diagnose this type of injury before surgical intervention. In the present study, we collected several imaging characteristics based on MRI and tried to determine whether those clues can be used to diagnose distal rupture of CFL specifically and sensitively. Several imaging characteristics based on MRI were collected and used to diagnose and determine the location of CFL injury. All these clues on preoperative MRI were verified by operative findings and postoperative roentgenography. The interobserver agreement for the quality of the MRI images had a p value of .6 (McNemar test) and a Cohen's kappa of 65.2% (confidence interval, 50.5%-79.9%), and the agreement of the 2 observers was categorized as substantial. The sensitivity and specificity of distal rupture of CFL between 2 observers were 76.3%, 91.4% and 72.2%, 85.55%, respectively. The sensitivity and specificity of MRI clues were calculated as follows: hyperintense signal changes (86.1%, 38.6%), peroneal sheath fluid (63.9%, 74.7%), wave or laxity of the ligament (80.6%, 51.8%), fluid exudation around the ligament (80.6%, 51.8%), bone marrow edema on the calcaneus insertion (2.8%, 91.6%), avulsion fracture of the calcaneus (0%, 96.4%), incongruency or disruption of the ligament (69.4%, 77.1%), and exudation on the subtalar joint (52.8%, 71.1%). Preoperative MRI scans are a useful tool to diagnose distal injury of the CFL.

Imaging Characteristics of the Proximal Lateral Collateral Ligament of the Knee: Findings on Ultrasound and MRI With Histologic Correlation.

OBJECTIVES: Determine prevalence of increased signal intensity of the lateral collateral ligament (LCL) of the knee on MRI and decreased echogenicity on ultrasound, and compare with cadaveric histologic evaluation. METHODS: After IRB approval of this prospective study with informed consent, patients having knee MRI were additionally evaluated with ultrasound. Signal intensities of LCL on MRI (low, intermediate, high), echogenicity at ultrasound (hyperechoic, hypoechoic, anechoic), and extent of findings were assessed. Descriptive statistics, Wilcoxon signed ranked test, and intraclass correlation coefficient (ICC) were calculated. Two cadaveric knees were imaged with MRI and ultrasound, including histologic LCL evaluation. RESULTS: Seventy-three subjects were included (39 males, 34 females; mean age 48 ± 14 years) with 77 knee examinations. On MRI, low, intermediate, and high signals were present in 21% (16/77), 75% (58/77), and 4% (3/77), respectively. On ultrasound, echogenicity was assessed as hyperechoic, hypoechoic, and anechoic in 62% (48/77), 38% (29/77), and 0% (0/77), respectively. Mean length of increased signal was 8.6 mm (±4.9) on MRI, and 6.5 mm (±4.8) on ultrasound. The ICC showed a good to excellent intermodality reliability (0.735-0.899) without statistically significant difference for interreader measurements (P = .163-.795). Histology evaluation showed transition of ligament fibers to fibrocartilage at its insertion with increased connective tissue mucin corresponding to MRI and ultrasound findings. CONCLUSIONS: Increased signal intensity of the proximal LCL on ultrasound and MRI is common and corresponds to normal connective tissue mucin.

The prevalence of posterior inferior tibiofibular ligament and inferior tibiofibular transverse ligament injuries in syndesmosis-injured ankles evaluated by oblique axial magnetic resonance imaging: a retrospective study.

BACKGROUND: Transverse ligament and posterior inferior tibiofibular ligament injuries have not been investigated till date because these are difficult to evaluate using standard magnetic resonance imaging. This study aimed to investigate the prevalence of transverse ligament and posterior inferior tibiofibular ligament injuries in syndesmosis-injured ankles using oblique axial magnetic resonance imaging. METHODS: The patients who were diagnosed with syndesmosis injury using magnetic resonance imaging (MRI) within 7 days of the trauma were included. Patients with concomitant fractures were excluded. A total of 34 patients (1 woman and 33 men) with an average age of 22 years (range, 14-64 years) were included. The anterior inferior tibiofibular, interosseous, transverse, and posterior inferior tibiofibular ligaments were classified as intact, partial tear, or complete tear using usual axial and oblique axial MRIs. RESULTS: There were 8 (23.5%) ankles with an intact, 21 (61.8%) ankles with a partially torn, and 5 (14.7%) ankles with a complete tear of transverse ligament. There were 20 (58.8%) ankles with an intact, 12 (35.3%) ankles with a partially torn, and 2 (5.9%) ankles with a complete tear of posterior inferior tibiofibular ligament. Overall, 50% of the transverse ligament injuries occurred without posterior inferior tibiofibular ligament involvement. CONCLUSIONS: The oblique axial magnetic resonance imaging scan revealed that the prevalence of transverse ligament and posterior inferior tibiofibular ligament injuries in syndesmosis-injured ankles were 76.5 and 41.2%, respectively.