OBJECTIVE: Knowledge of footprint anatomy is essential for ankle anterior talofibular ligament repair and reconstruction. We aimed to determine the intra- and inter-rater measurement reliability of the anterior talofibular ligament footprint dimension using three-dimensional MRI.
METHODS: MRI images of 20 ankles with intact ligaments, including 11 with a single bundle and nine with double-bundle ligaments, were analyzed. Imaging was performed using a 3.0-Tesla MRI. Isotropic three-dimensional proton density-weighted images with a voxel size of 0.6 mm were obtained. The fibular and talar footprints were manually segmented using image processing software to create three-dimensional ligament footprints. The lengths, widths, and areas of each sample were measured. A certified orthopedic surgeon and a senior orthopedic fellow performed the measurements twice at 6-week intervals. The intra- and inter-rater differences in the measurements were calculated.
RESULTS: The length, width, and area of the single-bundle fibular footprint were 8.7 mm, 5.4 mm, and 37.4 mm2, respectively. Those of the talar footprint were 8.4 mm, 4.3 mm, and 30.1 mm2, respectively. The inferior bundle of the double-bundle ligament was significantly smaller than the single and superior bundles (p < 0.001). No differences were observed between intra-rater measurements by either rater, with maximum differences of 0.7 mm, 0.5, and 1.7 mm2, in length, width, and area, respectively. The maximum inter-rater measurement differences were 1.9 mm, 0.5, and 2.4 mm2, respectively.
CONCLUSIONS: Measurements of the anterior talofibular ligament dimensions using three-dimensional MRI were sufficiently reliable. This measurement method provides in vivo quantitative data on ligament footprint anatomy.

OBJECTIVE: Anterior talofibular ligament (ATFL) insufficiency encompasses situations in which (i) frequent sprains cause ATFL loss, as evidenced by ATFL non-visualization on preoperative magnetic resonance imaging; or (ii) minimal healthy ATFL tissue for repair is left after the removal of the large os subfibulare. Suture tape implantation can be indicated for these cases rather than conventional ligament repair. This study was designed to investigate the incidence of post-operative re-sprain in patients who underwent suture tape implantation for ATFL insufficiency, and risk factors influencing the occurrence of post-operative re-sprain were identified.
METHODS: A total of 68 patients who underwent suture tape implantation for ATFL insufficiency from January 2016 to December 2021 were retrospectively evaluated. The minimum follow-up duration for inclusion was 2 years after surgery. All included patients were divided into two groups according to the presence of post-operative re-sprain during the follow-up period. Multiple clinico-radiographic parameters were measured, and binary logistic regression analysis was performed to determine the factors influencing post-operative re-sprain.
RESULTS: Post-operative re-sprain occurred in 19 of the 68 patients (27.9%), and multiple re-sprains persisted in 7 patients (10.3%). Post-operative re-sprain was more likely to occur in patients who smoked after surgery (odds ratio [OR], 3.510), had generalized ligament laxity (OR, 4.364) and engaged in occupations requiring high physical activity levels (OR, 4.421), including soldiers, professional athletes, student-athletes and mailmen.
CONCLUSIONS: The incidence of multiple post-operative re-sprains was high after suture tape implantation for ATFL insufficiency. Caution is particularly warranted in patients with risk factors, necessitating meticulous attention to their care. Careful consideration of strategies to mitigate risks when performing the surgery is also recommended.
METHODS: Level III.

BACKGROUND: We aimed to evaluate the intra- and interrater measurement reliability of the lateral ankle ligament attachment locations using three-dimensional magnetic resonance imaging.
METHODS: We analysed 54 participants with a mean age of 43 years who underwent three-dimensional ankle magnetic resonance imaging and had normal lateral ligaments. Bony landmarks of the distal fibula, talus, and calcaneus were identified in the reconstructed images. The centers of the anterior talofibular ligament and calcaneofibular ligament attachments were also identified. The distances between the landmarks and attachments were measured. Two raters performed the measurements twice, and intra- and interrater intraclass correlation coefficients were calculated.
RESULTS: The intrarater intraclass correlation coefficient values were between 0.71 and 0.96 for the anterior talofibular ligament attachment measurements and between 0.77 and 0.95 for the calcaneofibular ligament attachments. The interrater intraclass correlation coefficient was higher than 0.7, except for the distance between the anterior talofibular ligament superior bundle and fibular obscure tubercle. The fibular attachment of a single-bundle anterior talofibular ligament was located 13.3 mm from the inferior tip and 43% along the anterior edge of the distal fibula. The superior and inferior bundles of the double-bundle ligament were located at 43% and 23%, respectively. The calcaneofibular ligament fibular attachment was 5.5 mm from the inferior tip, at 16% along the anterior edge of the distal fibula.
CONCLUSIONS: The measurements of anterior talofibular ligament and calcaneofibular ligament attachment locations identified on three-dimensional magnetic resonance imaging were sufficiently reliable. This measurement method provides in vivo anatomical data on the lateral ankle ligament anatomy.

UNASSIGNED: Two types of suture anchor insertion pathways (anterolateral portal vs lateral accessory portal) are used in arthroscopic anterior talofibular ligament (ATFL) repair. However, it is not clear which one is the better choice. This study aims to compare the clinical outcomes of these 2 suture anchor insertion pathways when performing arthroscopic ATFL lasso-loop repair for the treatment of chronic lateral ankle instability (CLAI).
UNASSIGNED: From 2019 to 2021, patients with CLAI who underwent arthroscopic ATFL lasso-loop repair were retrospectively reviewed and divided into the anterolateral portal (ALP) group and the lateral accessory portal (LAP) group. A 1:1 propensity score matching was used to control confounding factors based on age, sex, body mass index, follow-up duration, preoperative visual analog scale (VAS) score, and Tegner score (ALP group, n = 26; LAP group, n = 26). Karlsson score, VAS score, Tegner score, operation time, anterior drawer test results, patient symptoms, and magnetic resonance (MR) evaluation of ATFL quality were used to describe the outcomes.
UNASSIGNED: The patient characteristics and follow-up durations were similar between the 2 groups. After a mean follow-up duration of 28.8 ± 2.3 months, the ALP group had significantly better Karlsson score, VAS score, and Tegner score improvement than the LAP group, with fewer symptoms. Seven patients in the LAP group still had a feeling of ankle instability, and 3 of them exhibited ankle laxity.
UNASSIGNED: In this study, we found that inserting the suture anchor through the anterolateral portal was associated with better outcomes compared to that through the lateral accessory portal when performing arthroscopic ATFL lasso-loop repair for CLAI patients. The improvement was greater for pain relief and function and was associated with a lower frequency of subjective ankle instability.

BACKGROUND: Even though 20% of chronic lateral ankle instability results from a combined anterior talofibular ligament (ATFL) and calcaneofibular ligament (CFL) injury, only the ATFL is sutured using arthroscopic ligament repair techniques. Although some biomechanical and clinical studies have proved that isolated ATFL repair yields excellent results, previous biomechanical studies were performed using systems that only allow indirect estimations. The purpose of this study was to clarify strain patterns by directly measuring repaired ATFL and CFL strain patterns on cadaveric models that underwent isolated ATFL repair of a combined ATFL and CFL injury.
METHODS: The miniaturization ligament performance probe (MLPP) system was used for directly measuring the strain patterns to insert the strain gauges into the mid-substance of normal and repaired ATFL and CFL fibers in five cadaveric specimens to allow measurement of strain patterns in the axial and three-dimensional motion of the ankle.
RESULTS: The normal and repaired ATFL showed similar strain patterns in axial and three-dimensional motions. During the axial range of motion of the ankle, the repaired CFL showed a strain pattern almost similar to that of normal CFL, but the strain increased as the plantar flexion or dorsiflexion angle increased to the maximum value of 100 at 30° plantarflexion or strain values of 17-55/100 at 15°dorsiflexion. During three-dimensional motion, the repaired CFL was under the maximum value of 100 during dorsiflexion-inversion and exhibited less strain (7-38/100) during plantar flexion-eversion.
CONCLUSIONS: The repaired CFL did not show a strain pattern that was completely consistent with a normal strain pattern; however, it did have some degree of tension similar to a normal strain pattern, even though it was not directly repaired.

OBJECTIVE: The aim of this study was to compare the clinical outcomes between patients with chronic ankle instability (CAI) undergoing arthroscopic anterior talofibular ligament (ATFL) repair who received elastic bandage treatment and those who received lower-leg cast immobilization.
METHODS: CAI patients with isolated ATFL injury undergoing arthroscopic ATFL repair from January 2017 and August 2019 were included in the study. The visual analogue scale (VAS) at rest and during activities, American Orthopedic Foot and Ankle Society (AOFAS) score, Karlsson Ankle Functional Score (Karlsson score), and time of returning to walk, walk normally, work and sports were evaluated preoperatively, and at 6 months and 12 months follow-up.
RESULTS: A total of 41 patients were included in this study. Among them, 24 patients accepted lower-leg cast fixation, and the other 17 patients were immobilized with elastic bandage. Compared to patients with lower-leg immobilization, patients with elastic bandage fixation had significantly lower VAS during activities (P = 0.021) and higher AOFAS score (P = 0.015) at 12 months follow-up. The Karlsson score at 6 months follow-up were significantly higher in elastic bandage group than those in lower-leg group (P = 0.011). However, no significant difference was observed in time of returning to walk, work and sports between the two groups.
CONCLUSIONS: Elastic bandage treatment was better than lower-leg cast immobilization in terms of eliminating pain symptom at 12 months follow-up, and improving ankle functional outcome at 6 months follow-up. Moreover, the present study emphasized that lower-leg cast immobilization offered no advantages in arthroscopic ATFL repair postoperative immobilization.
METHODS: Cohort study; Level of evidence, 3.

OBJECTIVE: 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.
目的: 探讨超声在评估踝关节骨折患者距腓前韧带（ATFL）及下胫腓前韧带远侧束（ATiFL-DF）损伤中的应用价值。方法: 收集2019年4月至2023年3月在浙江大学医学院附属邵逸夫医院因踝关节骨折就诊，临床怀疑韧带损伤，术前行踝关节超声检查，并予以踝关节镜探查的患者。以踝关节镜下检查结果为诊断金标准，评估韧带损伤分级，统计分析超声诊断ATFL及ATiFL-DF损伤的敏感度、特异度、阳性预测值和阴性预测值，并行Kappa一致性检验。结果: 共收集病例51例。超声诊断ATFL损伤的敏感度和特异度分别为100.0%和92.3%，阳性预测值为92.6%，阴性预测值为100.0%，超声与踝关节镜检查结果一致性佳（kappa=0.849）。超声诊断ATiFL-DF损伤的敏感度和特异度分别为86.7%和33.3%，阳性预测值为90.7%，阴性预测值为25.0%，超声与踝关节镜检查结果一致性差（kappa=0.168）。结论: 超声检查是评价踝关节骨折患者ATFL损伤的可靠的检查方式，但对ATiFL-DF损伤的评估特异性较差，因此ATiFL-DF损伤超声检查阴性的踝关节骨折患者仍有必要行踝关节镜检查。.

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UNASSIGNED: 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.
UNASSIGNED: To study the influence of DL injury on the biomechanical function of the ankle joint.
UNASSIGNED: 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 300 N and a 1.5 Nm 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.
UNASSIGNED: 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.
UNASSIGNED: 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.

UNASSIGNED: The lateral ankle joint comprises the anterior talofibular ligament (ATFL), calcaneofibular ligament (CFL), and posterior talofibular ligament (PTFL). The purpose of this study was to propose a classification of CFL morphology.
UNASSIGNED: The material comprised 120 paired lower limbs from human cadavers (30 male, 30 female), mean age 62.3 years. The morphology was carefully assessed, and morphometric measurements were performed.
UNASSIGNED: A 4-part method for anatomic classification can be suggested based on our study. Type 1 (48.3%), the most common type, was characterized by a bandlike morphology. Type 2 (9.2%) was characterized by a Y-shaped band, and type 3 (21.7%) by a V-shaped band. Type 4 (20.8%) was characterized by the presence of 2 or 3 bands. Type 2 and 4 were divided into further subtypes based on origin footprint.
UNASSIGNED: The aim of our study was to describe variations of calcaneofibular ligament. Our proposed 4-part classification may be of value in clinical practice in future recognition of CFL injuries and in its repair or reconstruction.
UNASSIGNED: The anatomy of the CFL plays an important role in stability of the ankle. Greater recognition of anatomical variation may help improve reconstructive options for patients with chronic lateral ankle instability.