Clinical significance of posterior talofibular ligament injury in chronic lateral ankle instability.

PURPOSE: Although arthroscopic repair of the anterior talofibular ligament (ATFL) is widely performed, the effect of posterior talofibular ligament (PTFL) injury on clinical outcomes remains unclear. This study aimed to evaluate the magnetic resonance imaging (MRI) findings of the PTFL in chronic lateral ankle instability (CLAI) and determine whether the presence or absence of PTFL injury affected the postoperative outcomes of arthroscopic ATFL repair. MATERIALS AND METHODS: Forty ankles of 35 patients who underwent arthroscopic repair for CLAI were included in this study as the experimental group, together with 25 ankles of 24 patients without CLAI as the control group. The PTFL thickness (PTFLT) and PTFL cross-sectional area (PTFLCSA) were measured using MRI and compared between the control and CLAI groups. The clinical outcomes of arthroscopic repair were compared between ankles with and without PTFL injuries. RESULTS: The mean PTFLT and PTFLCSA values were significantly higher in the CLAI group than in the control group. The PTFLT and PTFLCSA in the PTFL injury group were significantly larger than those in the non-injury group in the CLAI group. Postoperatively, there were no significant differences in clinical scores and talar tilt angles on stress radiographs between ankles with and without PTFL injury; however, instability recurrence was frequently observed in ankles with PTFL injury (32.1%) compared to the ankles without PTFL injury (16.7%). Poor-quality ATFL remnant, ATFL inferior fascicle, and calcaneofibular ligament injuries were frequently observed in ankles with PTFL injuries. CONCLUSIONS: Our findings indicate that PTFL injury is highly associated with CLAI but it does not affect postoperative clinical scores. However, postoperative instability recurrence was more often observed in ankles with PTFL injuries, given that they frequently have poor-quality ATFL remnants and CFL injuries. EVIDENCE LEVEL: Level III.

The ATFL inferior fascicle, the CFL and the PTFL have a continuous footprint at the medial side of the fibula.

PURPOSE: Knowledge of the complex anatomy of the lateral ankle ligaments is essential to understand its function, pathophysiology and treatment options. This study aimed to assess the lateral ligaments and their relationships through a 3D view achieved by digitally marking their footprints. METHODS: Eleven fresh-frozen ankle specimens were dissected. The calcaneus, talus and fibula were separated, maintaining the lateral ligament footprints. Subsequently, each bone was assessed by a light scanner machine. Finally, all the scans were converted to 3D polygonal models. The footprint areas of the talus, calcaneus and fibula were selected, analysed and the surface area was quantified in cm2. RESULTS: After scanning the bones, the anterior talofibular ligament inferior fascicle (ATFLif), calcaneofibular ligament (CFL) and posterior talofibular ligament (PTFL) footprints were continuous at the medial side of the fibula, corresponding to a continuous footprint with a mean area of 4.8 cm2 (± 0.7). The anterior talofibular ligament (ATFL) footprint on the talus consisted of 2 parts in 9 of the 11 feet, whilst there was a continuous insertion in the other 2 feet. The CFL insertion on the calcaneus was one single footprint in all cases. CONCLUSION: The tridimensional analysis of the lateral ligaments of the ankle demonstrates that the ATFLif, CFL and PTFL have a continuous footprint at the medial side of the fibula in all analysed specimens. These data can assist the surgeon in interpreting the ligament injuries, improving the imaging assessment and guiding the surgeon to repair and reconstruct the ligaments in an anatomical position.

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.

The anterior talofibular ligament-posterior talofibular ligament angle decreased after ankle lateral stabilization surgery.

PURPOSE: The angle between the anterior talofibular ligament (ATFL) and the posterior talofibular ligament (PTFL) is increased in patients with chronic ATFL injury. This study aimed to compare the AFTL-PTFL angle before versus after ankle lateral stabilization surgery, and to evaluate whether the ATFL-PTFL angle correlates with the ligament injury severity. METHODS: This retrospective study included 48 patients with mechanical ankle instability treated between 2016 and 2018. After arthroscopic evaluation, all patients underwent ankle lateral stabilization surgery comprising ligament repair (n = 28) or reconstruction (n = 20). The ATFL-PTFL angle was measured in the axial plane on pre- and postoperative MRI. Comparisons were made of the pre- versus postoperative ATFL-PTFL angles, and the ATFL-PTFL angle of the repair versus reconstruction groups. Receiver operating characteristic (ROC) curve analysis was used to assess the diagnostic performance of the ATFL-PTFL angle in selecting the surgical technique. RESULTS: The postoperative ATFL-PTFL angle was significantly decreased compared with preoperatively. The ATFL-PTFL angle was significantly smaller in the repair group than the reconstruction group preoperatively and postoperatively. The area under the ROC curve was 0.741 (P < 0.01). The optimal cutoff point for the selection of ligament reconstruction was an ATFL-PTFL angle of 89.4° (sensitivity 0.85, specificity 0.61). CONCLUSION: The ATFL-PTFL angle decreases after ankle lateral stabilization surgery. The ATFL-PTFL angle is related to the severity of the ATFL injury. Ankle lateral ligament reconstruction should be considered when the ATFL-PTFL angle is > 89.4°. LEVEL OF EVIDENCE: Level III.

A Rare Pattern of Ligamentous Injury of the Ankle: A Case Report and Review of the Literature.

Ankle sprains are the most frequent sport related injuries with involvement of the lateral collateral ligament complex occurring in 85% of cases. Isolated anterior talofibular ligament injury is by far the commonest followed by combined anterior talofibular and calcaneofibular ligament strain. The posterior talofibular ligament is the strongest component of the lateral collateral ligament complex and is injured in severe ankle injury along with the other lateral collateral ligaments. While isolated calcaneofibular ligament strain has been reported, calcaneofibular ligament and posterior talofibular ligament strains with an intact anterior talofibular ligament are rare and reported in cadaveric studies. We present a case of radiologically diagnosed calcaneofibular ligament and posterior talofibular ligament injury and will discuss the anatomy, stress radiography, and magnetic resonance image findings and the mechanism of this particular injury.

Increased ATFL-PTFL angle could be an indirect MRI sign in diagnosis of chronic ATFL injury.

PURPOSE: Magnetic resonance imaging (MRI) has relatively low accuracy in diagnosing chronic anterior talofibular ligament (ATFL) injury. This study's purpose was to evaluate the angle between the ATFL and posterior talofibular ligament (PTFL) as a new indirect MRI sign of chronic ATFL injury in patients with mechanical ankle instability (MAI). METHODS: This study included 200 participants: 105 patients with MAI and 95 patients seen at our institution for reasons unrelated to ankle instability. MR images of all 200 participants were reviewed. The ATFL-PTFL angle in the axial plane was measured and compared between groups. Receiver operating characteristic curves (ROC) were used to analyze ATFL-PTFL angles in participants with and without ATFL injury. The sensitivity and specificity of this method for diagnosing ATFL injury were calculated. RESULTS: The mean ATFL-PTFL angle was significantly larger among MAI patients than among control patients (81.5° ± 9.8° vs 75.2° ± 8.9°, respectively; P < 0.01). The area under the ROC was 0.789 (P < 0.01). The optimal cut-off point for diagnosing ATFL injury on the basis of the ATFL-PTFL angle was 79.0° (sensitivity 0.89, specificity 0.67). CONCLUSION: The ATFL-PTFL angle was significantly larger among MAI patients than among those without MAI. Increased ATFL-PTFL angle offers a new indirect MRI sign for diagnosing chronic ATFL injury. The ATFL-PTFL angle can be used not only to improve the accuracy of diagnosis of chronic ATFL injury, but also to evaluate the restoration of normal ankle joint geometry after lateral ligament reconstruction. LEVEL OF EVIDENCE: III.

The lateral ankle ligaments are interconnected: the medial connecting fibres between the anterior talofibular, calcaneofibular and posterior talofibular ligaments.

PURPOSE: A deep knowledge of lateral ankle ligaments is necessary to understand its function, pathophysiology and treatment options. The ankle lateral collateral ligament is formed by the anterior talofibular ligament (ATFL), the calcaneofibular (CFL) and the posterior talofibular ligament (PTFL). Although previous studies have reported connections between these ligaments on its lateral side, no studies have specifically assessed connections on the medial side. The aim of this study was to assess the morphology and consistency of the medial connections between the components of the lateral collateral ligament complex of the ankle. METHODS: Forty fresh-frozen ankle specimens were dissected to look for connections between the three lateral ankle ligaments. After visualization of the lateral ligaments was achieved, the fibula was amputated and ligament insertions were released at the talar and calcaneal insertion points. Observation of the connections and video analysis of the dynamic relationships of ligament connections were performed. RESULTS: Connections were found in all cases between the ATFL and PTFL, the ATFL and CFL, and the CFL and PTFL. Connections between ATFL and PTFL were not homogeneous. Although connections between the ATFLif and PTFL were noted in all cases (40), only 17 ankles (42.5%) had connections between the ATFLsf and PTFL. The amount of fibres of connection was also variable. CONCLUSION: Connections between the three components of the lateral collateral ligament of the ankle may be observed from the medial aspect of the ankle, and this may have important implications for arthroscopic lateral ligament repair.

Morphological characteristics of the lateral ankle ligament complex.

PURPOSE: The relevance of each ligament comprising the lateral ankle ligament complex, including the anterior talofibular ligament (ATFL), calcaneofibular ligament (CFL), and posterior talofibular ligament (PTFL), has not been sufficiently elucidated; therefore, we aimed to clarify the morphological characteristics and relevance of these ligaments. METHODS: Total 152 legs from 152 Japanese cadavers were investigated. The lengths and widths of the ATFL, CFL, and PTFL were measured using a caliper. The ATFL was classified according to the number of fiber bundles (Types I, II, and III corresponded to one, two, and three fiber bundles, respectively), and the lengths and widths of the three ligaments were compared between the Type groups. In addition, the ratio of each ligament's length and width to the tibial length was calculated, and the correlation of the ratio of ligament length and width between the ATFL, CFL, and PTFL was examined about 34 legs. RESULTS: The ATFL, CFL, and PTFL were found to connect at the anterior/inferior tip of the lateral malleolus each other. The Type II group of the ATFL was most common (54.6%) in our investigated specimens. However, there were no significant inter-group differences in the lengths and widths of the CFL and PTFL. CONCLUSIONS: This study demonstrates that the lateral ankle ligaments may stabilize the ankle joint through interconnections.

Continuous and Connective Fibers of the Lateral Ankle Ligament Complex.

The lateral ankle ligament complex (LALC) is an intricate structure; therefore precise anatomic knowledge is required by the surgeon. However, the structural relationship of the LALC remains unclear. Here, the features of the posterior talofibular ligament (PTFL) and the relationship to the LALC at the distal fibula were clarified in a cadaver study. The lengths of most of the anterior and posterior parts, and the widths of the anterior-posterior and superior-inferior parts, were measured with a digital caliper. In addition, the relationship between the anterior talofibular ligament (ATFL) and PTFL inside of the capsule is described. The small fiber bundles of the PTFL were manually divided, and the footprint of each bundle at the fibula and talus was clarified. The relationship between the ATFL and CFL, outside of the capsule, was examined on axial slices at the inferior fibula. The lengths of the most anterior and most posterior parts of the PTFL were 9.8 ± 1.7 and 29.4 ± 1.9 mm, respectively. The widths of the anterior-posterior and superior-inferior parts were 10.0 ± 0.9 and 5.8 ± 1.1 mm, respectively. Approximately 83% of the fibers between the ATFL and PTFL were continuous. The anterior-inferior fibers of the PTFL were continuous with the inferior fibers of the ATFL inside of the capsule. The ATFL and CFL converged with connective tissue from outside of the capsule at the distal fibula. The results of this study should prove useful to further clarify the relationships of the LALC both inside and outside of the capsule at the distal fibula.

The anatomic variations of the posterior talofibular ligament associated with os trigonum and pathologies of related structures.

PURPOSE: The aim of this study is to investigate the detailed anatomy of the posterior talofibular ligament (PTFL) on MR images in patients with os trigonum. We also evaluated the pathological conditions of the PTFL, anterior talofibular ligament (ATFL), flexor hallucis longus (FHL) tendon, talus and os trigonum. METHODS: Ankle MRIs of 70 patients with os trigonum (study group) and 70 patients without it (control group) were reviewed for the anatomy of the anterior and posterior fibers of PTFL. The prevalence of PTFL and ATFL pathologies was also compared between two groups. Additionally FHL tenosynovitis and osseous pathologies were evaluated. RESULTS: The posterior fibers inserted into the lateral tubercule of the posterior process of the talus in the control group whereas if an os trigonum was present, the posterior fibers of PTFL were inserted only into the os trigonum. The origins of anterior and posterior fibers were the medial surface of the lateral malleolus and the insertion of the anterior fibers was lateral surface of the talus posterior to the lateral malleolar facet in both groups. There was a significant association between an abnormal PTFL, ATFL and the presence of os trigonum. FHL tenosynovitis was higher in the study group but it did not meet the statistical significance. The most common pathology of the talus and os trigonum was subchondral edema along the synchondrosis. CONCLUSIONS: In patients with os trigonum, the posterior fibers of the PTFL were inserted herein. In the case of an os trigonum signal alterations of ligaments were more common, which may reflect chronic instability.

The Specific Anatomical Morphology of Lateral Ankle Ligament: Qualitative and Quantitative Cadaveric based Study.

OBJECTIVE: The accurate understanding in morphological features of the lateral ankle ligaments is necessary for the diagnosis and management of ankle instability and other ankle problems. The purpose of this study was to evaluate the anatomical morphology and the attachment areas of lateral ligament complex of ankle joint based on the cadaveric study. METHODS: Fifty-four fresh frozen cadaveric ankles were dissected to evaluate the lateral ankle ligaments. Each ligament was separated into two or three small bundles. In the investigated footprint areas, acrylic colors were used as a marker point to locate specific areas of ligament bundle attached to the bone. The Image J software was used to measure and analyze the sizes of the specific footprint areas to achieve descriptive statistical analysis. RESULTS: The double bands of anterior talofibular ligament (ATFL) were found as a major type in the present study with 57.41% (31 of 54 ankles) while the single band of ATFL was observed in 42.59% (23 of 54 ankles). The attachment sizes of the ATFL, posterior talofibular ligament (PTFL) and calcaneofibular ligament (CFL) were evaluated into two areas; proximal and distal attachments. The average of proximal or fibular part of ATFL, PTFL and CFL were 85.06, 134.27, 93.91 mm2 respectively. The average of distal part of ATFL, PTFL and CFL were 100.07, 277.61, 249.39 mm2 respectively. CONCLUSION: Considering the lateral ankle ligament repaired or reconstruction especially using arthroscopy, the precise understanding in specific detail of the lateral ankle ligament may help both diagnose and select the appropriate treatment for solving the ankle problems. These observations may help the surgeon to perform the surgical procedure for determining the appropriate techniques and avoid complication to patients.

Approach to Ankle Instability in Patients With a Negative Ankle MRI: A Case Series.

Objectives Injuries to the ankle ligaments are some of the most common musculoskeletal sports injuries. Ankle magnetic resonance imaging (MRI) is the standard diagnostic procedure in today's practice, but its reliability and validity remain controversial. The aim of this study was to explore the approach for patients with negative ankle MRI who continue to have symptoms of ankle instability despite conservative therapy. Methods A total of eight patients who were 14 years or older with negative ankle MRI who continue to have symptoms of ankle instability despite conservative therapy were admitted to our institution from January 1, 2015 to December 31, 2021. Results Eight patients with a mean age of 36, and a mean body mass index (BMI) of 37.7. All patients presented with ankle pain, locking, and giving way in variable severity. All the patients had a radiograph followed by an ankle MRI, which showed normal alignment of ankle joints without abnormality. Initially, all patients were treated conservatively but did not show any improvement. After that, they underwent an operation of lateral ankle ligament reconstruction by modified Brostrom technique, followed by casting and physiotherapy. The symptoms of ankle instability resolved in all patients. The ankle pain resolved completely in six patients, improved in one patient, and did not improve in one patient.  Conclusion Based on our results, we advocate reconstruction surgery by modified Brostrom technique for ligament repair in patients with clinical evidence of chronic ankle instability who have failed a trial of conservative management, even in the context of a normal ankle MRI.

Functional and Kinetic Treatment With Rehabilitation Combined With Cryotherapy Compared to Cryotherapy Alone in the Treatment of Acute Grade I or II Inversion Ankle Sprains: A Randomized Clinical Trial.

Objective: The purpose of this study was to compare Functional and Kinetic Treatment with Rehabilitation (FAKTR) combined with cryotherapy to cryotherapy alone in the treatment of acute grade I or II inversion ankle sprains. Methods: This prospective, randomized clinical trial of adult (18-40 years of age) participants (n = 40) with acute grade I or II inversion ankle sprain of less than 3 weeks, who were randomly allocated into a FAKTR and cryotherapy group (n = 20) or a cryotherapy only group (n = 20). The participants had 3 treatments (inclusive of the initial consultation), with a fourth as a measurement follow-up (2 weeks after the third treatment). Measurement procedures were completed at the outset of the first to third consultations and the fourth measurement only consultation. Clinical measures taken by a blinded research assistant included the Numerical Pain Rating Scale, Foot function index, algometer, digital inclinometer for ankle dorsiflexion range of motion measures, the figure-of-8 maneuver measured swelling, and the Stork-Balance-Stand Test. Results: Significant intergroup differences were observed for pain rating (P ≤ .01; 95% confidence interval [CI] -4.74 to 0.86), pain pressure threshold (P ≤ .05; 95% CI -1.06 to 1.52), balance and proprioception (P ≤ .01; 95% CI -5.28 to -1.39), and foot function index (P ≤ .01; 95% CI -30.12 to 4.83). No significant intergroup differences were observed in ankle dorsiflexion range of motion (P = .242; 95% CI -3.17 to 1.20) and edema measurements (P = .602; 95% CI 0.41-1.46). Conclusion: The FAKTR instrument assisted soft tissue mobilization treatment combined with cryotherapy indicated a trend toward greater clinical effectiveness than cryotherapy for measures of pain, pain pressure threshold, balance and proprioception, and foot function index; however, these outcomes were not reflected for ankle dorsiflexion range of motion and edema measurements.

Sonographic visibility of the main posterior ankle ligaments and para-ligamentous structures in 15 healthy subjects.

The present article describes the ultrasound (US) appearance of ligaments and paraligamentous structures which are not included in standard US imaging of the ankle: the posterior inferior tibiofibular ligament (PITFL), the transverse tibiofibular ligament (TTFL), the posterior talofibular ligament (PTFL), the posterior intermalleolar ligament (PIL), the synovial recess (SR) of the posterior joint and the os trigonum (OT). Two skilled operators examined 15 ankles in 15 healthy volunteers. Correlation between thickness of the main ligaments and body mass index (BMI) was also analyzed. Compound and tissue harmonic imaging (THI) were carried out using 12-, 6-15- and 9-MHz linear probes. Exploration of the posterior ankle ligament complex is accurately described including correct ankle position, echogenicity, shape, direction and thickness. Both operators identified and measured the main ligaments (PITFL, TTFL and PTFL) in all volunteers (Intraclass Correlation Coefficient ranged from 0.8 to 1); both operators also detected SR and OT in 2/15 ankles and posterior intermalleolar ligament (PIL) in 5/15 ankles. Pearson's test showed a significant correlation (< 0.05) between TTFL thickness and BMI. Also, a dynamic study was carried out showing tension of the PTFL during dorsiflexion in 7/15 subjects. Our results highlight the potential role of accurate US imaging in detecting posterior ankle ligament involvement in acute and chronic traumas. To our knowledge, there are no previous articles in the literature dealing with this topic providing an accurate description of the US procedure, and in particular, no study has been carried out to identify OT.

Radiographic identification of the primary lateral ankle structures.

BACKGROUND: Lateral ankle ligament injuries rank among the most frequently observed athletic injuries, requiring repair or reconstruction when indicated. However, there is a lack of quantitative data detailing the ligament attachment sites on standard radiographic views. PURPOSE: To quantitatively describe the anatomic attachment sites of the anterior talofibular ligament (ATFL), calcaneofibular ligament (CFL), and posterior talofibular ligament (PTFL) on standard radiographic views with respect to reproducible osseous landmarks to assist with intraoperative and postoperative assessment of lateral ankle ligament repairs and reconstructions. STUDY DESIGN: Descriptive laboratory study. METHODS: Twelve nonpaired, fresh-frozen cadaveric foot and ankle specimens were dissected to identify the origins and insertions of the 3 primary lateral ankle ligaments. Ligament footprint centers were marked with 2-mm stainless steel spheres shallowly embedded at the level of the cortical bone prior to obtaining standard lateral and mortise radiographs. Measurements were performed twice by 2 blinded raters independently to calculate mean distances and assess reliability via intraclass correlation coefficients (ICCs). RESULTS: Radiographic measurements demonstrated excellent reproducibility between raters (all interobserver ICCs>0.97) and across trials (all intraobserver ICCs>0.99). On the lateral view, the ATFL fibular attachment (mean±SD) was 8.4±1.8 mm proximal and anterior to the inferior tip of the lateral malleolus and attached on the talus 13.8±2.0 mm proximal and anterior to the apex of the lateral talar process. The CFL originated 5.0±1.4 mm superior and anterior to the inferior tip of the lateral malleolus and inserted on the calcaneus 18.5±4.6 mm posterior and superior to the posterior point of the peroneal tubercle. On the mortise view, the ATFL origin was 4.9±1.4 mm proximal to the inferior tip of the lateral malleolus and inserted on the talus 9.0±2.1 mm medial and superior of the apex of the lateral talar process and 18.9±3.1 mm inferior and slightly lateral to the superior lateral corner of the talar dome. The fibular CFL origin was 2.9±1.6 mm proximal and slightly medial to the inferior tip of the lateral malleolus and inserted on the calcaneus 18.0±5.1 mm distal to the apex of the lateral talar process. CONCLUSION: Radiographic parameters quantitatively describing the anatomic origins and insertions of the lateral ankle ligaments were defined with excellent reproducibility and agreement between reviewers. CLINICAL RELEVANCE: Quantitative radiographic anatomy data will assist in preoperative planning, improve intraoperative localization, and provide objective measures for postoperative assessment of anatomic repairs and reconstructions.