Balance Control Deficits are Associated with Diminished Ankle Force Sense, Not Position Sense, in Athletes with Chronic Ankle Instability.

OBJECTIVES: To compare balance control and ankle proprioception between athletes with and without chronic ankle instability (CAI). A further objective was to explore the relationship between balance control performance and ankle proprioception in athletes with CAI. DESIGN: Cross-sectional study. SETTINGS: Sports Rehabilitation Laboratory. PARTICIPANTS: Eighty-eight recreational athletes (47 CAI and 41 healthy control) were recruited. INTERVENTIONS: No applicable. MAIN OUTCOME MEASURES: Balance control performance was assessed using the sway velocity of the centre of the pressure during the one-leg standing tasks. Ankle proprioception, including joint position sense and force sense, were tested using absolute error (AE) associated with joint position reproduction and force reproduction tasks in four directions, i.e., plantarflexion, dorsiflexion, inversion, and eversion. RESULTS: Athletes with CAI performed significantly worse than those without CAI in balance control tasks. In addition, CAI athletes showed significantly worse joint position sense and force sense in all three movement directions tested (plantarflexion, inversion, and eversion). Correlation analysis showed that the AE of the plantarflexion force sense was significantly moderately correlated with medial-lateral sway velocity in the one-leg standing with eyes open and closed conditions (r = 0.372-0.403, p = 0.006-0.012), and the AE of inversion force sense was significantly moderately correlated with medial-lateral sway velocity in the one-leg standing with eyes open (r = 0.345, p = 0.018) in athletes with CAI, but the joint position sense measures were not (all p > 0.05). CONCLUSIONS: Athletes with CAI showed significantly impaired balance control performance and diminished ankle proprioception. Deficit in force sense was deemed as a moderate predictor of one-leg standing balance control deficits in athletes with dominant-side injury CAI, while ankle position sense may be a small predictor.

Effects of Kinesio taping on lower limb biomechanical characteristics during unexpected jumping in patients with chronic ankle instability.

PURPOSE: The current biomechanical research on the application of Kinesio taping (KT) to patients with chronic ankle instability (CAI) has focused on testing the expected movements. However, unexpected movements are more common in actual sports. Therefore, the present study aimed to investigate the effects of KT on the biomechanical characteristics of the knee and ankle joints during unexpected jumping movements. METHODS: Twenty-one patients with unilateral CAI were recruited to capture the biomechanical parameters during unexpected jumping movements under different interventions: no taping (NT), placebo taping (PT), and KT. A one-way repeated measures analysis of variance was used to compare the differences in knee and ankle biomechanical characteristics among patients with CAI between the three intervention conditions. RESULTS: At initial contact, the KT group demonstrated a significant decrease in ankle plantarflexion and knee flexion angles compared to the NT group (p < 0.05). At the early landing phase, the KT group had a significant increase in peak ankle dorsiflexion angle, peak ankle eversion angle, peak ankle dorsiflexion moment, and peak ankle eversion moment compared to the NT and PT groups (p < 0.05). Furthermore, the KT group had a significantly reduced peak knee flexion angle, peak knee eversion angle, and peak vertical ground reaction force (p < 0.05) compared to the NT and PT groups. CONCLUSION: KT significantly improves the sprain-prone touchdown posture of patients with CAI. And reducing the risk of ankle sprains during the early landing phase by promoting ankle dorsiflexion and eversion angles and moments.

Individuals with chronic ankle instability show altered regional activation of the peroneus longus muscle during ankle eversion.

Individuals with chronic ankle instability (CAI) present muscular weakness and potential changes in the activation of the peroneus longus muscle, which likely explains the high recurrence of ankle sprains in this population. However, there is conflicting evidence regarding the role of the peroneus longus activity in CAI, possibly due to the limited spatial resolution of the surface electromyography (sEMG) methods (i.e., bipolar sEMG). Recent studies employing high-density sEMG (HD-sEMG) have shown that the peroneus longus presents differences in regional activation, however, it is unknown whether this regional activation is maintained under pathological conditions such as CAI. This study aimed to compare the myoelectric activity, using HD-sEMG, of each peroneus longus compartment (anterior and posterior) between individuals with and without CAI. Eighteen healthy individuals (No-CAI group) and 18 individuals with CAI were recruited. In both groups, the center of mass (COM) and the sEMG amplitude at each compartment were recorded during ankle eversion at different force levels. For the posterior compartment, the sEMG amplitude of CAI group was significantly lower than the No-CAI group (mean difference = 5.6% RMS; 95% CI = 3.4-7.6; p = 0.0001). In addition, it was observed a significant main effect for group (F1,32 = 9.608; p = 0.0040) with an anterior displacement of COM for the CAI group. These findings suggest that CAI alters the regional distribution of muscle activity of the peroneus longus during ankle eversion. In practice, altered regional activation may impact strengthening programs, prevention, and rehabilitation of CAI.

Clinical outcomes of arthroscopic all-inside anterior talofibular ligament suture augmentation repair versus modified suture augmentation repair for chronic ankle instability patients.

BACKGROUND: To compare the clinical efficacies of arthroscopic anterior talofibular ligament suture augmentation repair and modified suture augmentation repair in patients with chronic ankle instability (CAI). METHODS: From October 2019 to August 2020, 100 patients with CAI were enrolled after propensity score matching analysis and observed for two years. Among them, 50 underwent modified suture augmentation repair and the other 50 underwent suture augmentation repair. The clinical efficacies of CAI treatments were evaluated using the American Orthopedic Foot and Ankle Society (AOFAS) clinical rating scale, visual analog scale (VAS), and anterior drawer test scores. RESULTS: The postoperative AOFAS score of the modified suture augmentation repair group (83.8 ± 11.3) was significantly higher than that of the suture augmentation repair group (76.3 ± 11.3; P = 0.001). The VAS (P = 0.863) and anterior drawer test (P = 0.617) scores were not significantly different between the two treatment groups. CONCLUSION: Both the modified suture augmentation repair and suture augmentation repair demonstrated good clinical efficacies. The AOFAS score of the modified suture augmentation repair group was superior to that of the conventional suture augmentation repair group. Thus, modified suture augmentation repair is a feasible and practical surgical technique for CAI treatment.

Transformer-based Multi-label Deep Learning Model is Efficient for Detecting Ankle Lateral and Medial Ligament Injuries on MRI and Improving Clinicians' Diagnostic Accuracy for Rotational Chronic Ankle Instability.

PURPOSE: To develop a deep learning (DL) model that can simultaneously detect lateral and medial collateral ligament injuries of the ankle, aiding in the diagnosis of chronic ankle instability (CAI), and assess its impact on clinicians' diagnostic performance. METHODS: DL models were developed and external validated on retrospectively collected ankle MRIs between April 2016 and March 2022 respectively at three centers. Included patients were confirmed diagnoses of CAI through arthroscopy, as well as individuals who had undergone MRI and physical examinations that ruled out ligament injuries. DL models were constructed based on a multi-label paradigm. A transformer-based multi-label DL model (AnkleNet) was developed and compared with four convolution neural network (CNN) models. Subsequently, a reader study was conducted to evaluate the impact of model assistance on clinicians when diagnosing challenging cases: identifying rotational CAI (RCAI). Diagnostic performance was assessed using area under the receiver operating characteristic curve (AUC). RESULTS: Our transformer-based model achieved AUC of 0.910 and 0.892 for detecting lateral and medial collateral ligament injury, respectively, both of which was significantly higher than that of CNN-based models (all P < 0.001). In terms of further CAI diagnosis, it exhibited a macro-average AUC of 0.870 and a balanced accuracy of 0.805. The reader study indicated that incorporation with our model significantly enhanced the diagnostic accuracy of clinicians (P = 0.042), particularly junior clinicians, and led to a reduction in diagnostic variability. The code of the model can be accessed at https://github.com/ChiariRay/AnkleNet. CONCLUSION: Our transformer-based model was able to detect lateral and medial collateral ligament injuries based on MRI and outperformed CNN-based models, demonstrating a promising performance in diagnosing CAI, especially RCAI patients.

A quantitative assessment of the anterior tibiofibular gap with and without weight-bearing in healthy adults: An ultrasound-based study.

BACKGROUND: Difficulties in the accurate evaluation of tibiofibular clear space in plain radiographs are diagnostic problems in the clinical setting of syndesmosis injury. This study aimed to quantify the anterior tibiofibular gap (ATFG) with weight-bearing using ultrasonography. METHODS: In total, 32 healthy adults (16 men and 16 women) with 64 feet participated in this cross-sectional study. The ATFG was measured along the anterior inferior tibiofibular ligament for a US assessment conducted in both sitting and standing postures. The ankle joint was set on the tilt table at four different angles as follows: plantar flexion, 20° (P20); neutral position (N); dorsiflexion, 20° (D20); and dorsiflexion, 20°+ external rotation, 30° (D20ER30). The ankle joint position, sex, and side-to-side values were compared with and without weight-bearing. RESULTS: Under all ankle angle conditions, the ATFG was wider in the standing posture than in the sitting posture (p < 0.001). In both sitting and standing postures, the ATFG widened with increasing dorsiflexion angle, eventually reaching a maximum at D20ER30. The widening ratio (D20ER30/N) in the standing posture was higher in women than in men (p < 0.05). No statistical differences were identified side-to-side differences in the ATFG. CONCLUSIONS: Ultrasound measurements for identifying unphysiological increases in ATFG with weight bearing, especially given the side-to-side differences, may provide a means for quantitatively assessing syndesmosis injury in a clinical setting. Further research is warranted to clarify direct attribution as a clinical diagnostic utility of the ATFG measurements for syndesmosis injuries.

Enhancing Post-Surgical Rehabilitation Outcomes in Patients with Chronic Ankle Instability: Impact of Subtalar Joint Axis Balance Exercises Following Arthroscopic Modified Broström Operation.

Background and Objectives: This study aimed to evaluate the effects of subtalar joint axis-based balance exercises on the anterior talofibular ligament (ATFL) thickness, ankle strength, and ankle stability after an arthroscopic modified Broström operation (AMBO) for chronic ankle instability (CAI). Materials and Methods: The study included 47 patients diagnosed with CAI who underwent AMBO and were randomly divided into three groups: control (n = 11), general balance exercise (n = 17), and subtalar joint axis balance exercise (n = 19), regardless of the affected area. Participants in the exercise rehabilitation group performed exercises for 60 min twice a week for six weeks, starting six weeks after AMBO. ATFL thickness, ankle strength, and ankle dynamic stability were measured using musculoskeletal ultrasonography, Biodex, and Y-balance test, respectively, before and after treatment. Results: Compared with the remaining groups, the subtalar joint axis balance exercise group had reduced ATFL thickness (p = 0.000), improved ankle strength for eversion (p = 0.000) and inversion (p = 0.000), and enhanced ankle stability (p = 0.000). Conclusions: The study results suggest that subtalar joint axis-based balance exercises may contribute to the early recovery of the ankle joint after AMBO.

The morphology of osseous structure in subtalar joint with chronic ankle instability.

BACKGROUND: Osseous structures have been demonstrated as risk factors for chronic ankle instability (CAI). Previously, the researchers only focused on the osseous structures of ankle, but ignored the osseous structures of subtalar joint(STJ). Accordingly, the aim of our study was to investigate the morphological characteristics of STJ osseous structures in CAI. METHODS: 52 patients with CAI and 52 sex- and age- matched control subjects were enrolled from The Affiliated Traditional Chinese Medicine Hospital of Southwest Medical University. The lateral radiographs of ankle in weight-bearing were used to compare the diversity of the two groups. Specifically, The Length of calcaneus, Calcaneal facet height and Absolute foot height, Böhler's angle, Gissane's angle, Calcaneal inclination angle, Talocalcaneal angle, Tibiotalar angle, Tibiocalcaneal angle, Talar-horizontal angle, talar declination angle, facet inclination angle were gauged in the two groups. RESULTS: The Böhler's angle, Calcaneal inclination, Talocalcaneal angle, Tibiotalar angle, Talar-horizontal angle, Talar declination angle, Facet inclination angle and Absolute foot height of CAI group were significantly higher than normal control group (P < 0.05). There were no significant differences in Gissane's angle, Tibiocalcaneal angle, Length of calcaneus and Calcaneal facet height between patients with CAI and normal controls (P > 0.05). CONCLUSIONS: The osseous structures of STJ in CAI patients are different from normal people in morphology. Therefore, we should pay more attention to the changes of STJ anatomical parameters in the diagnosis and prevention of CAI. LEVEL OF EVIDENCE: Ⅲ.

Biomechanical Effects of Chronic Ankle Instability on the Talar Cartilage Matrix: The Value of T1ρ Relaxation Mapping Without and With Mechanical Loading.

BACKGROUND: T1ρ mapping has been proposed for the detection of early cartilage degeneration associated with chronic ankle instability (CAI). However, there are limited data surrounding the influence of ankle loading on T1ρ relaxation. PURPOSE: To evaluate T1ρ relaxation times of talar cartilage, as an indicator of early degenerative changes, associated with CAI and to investigate the influence of acute axial in situ loading on T1ρ values in CAI patients and healthy controls. STUDY TYPE: Prospective. SUBJECTS: A total of 9 patients (age = 21.8 ± 2.5 years, male/female = 2/7) with chronic ankle instability and 18 healthy control subjects (age = 22.8 ± 3.6 years, male/female = 5/13). FIELD STRENGTH: 3 T. SEQUENCE: 3D gradient echo fast low-angle shot (FLASH) sequence augmented with a variable spin-lock preparation period. ASSESSMENT: Ankle T1ρ mapping was performed without and with axial loading of 500 N. The talar cartilage was segmented in five coronal slices covering the central talocrural joint. Median talar T1ρ values were separately calculated for the medial and lateral facets. STATISTICAL TESTS: Mann-Whitney U and Wilcoxon signed-rank tests, significance level: P < 0.05. RESULTS: For the combined cohorts, the statistical analysis yielded significantly lower T1ρ values with loading compared to the no-load measurement for both the lateral (no load: [51.0 ± 4.0] msec, load: [49.5 ± 5.4] msec) as well as the medial compartment (no load: [50.0 ± 5.4] msec, load: [47.8 ± 6.8] msec). In the unloaded scans, the CAI patients showed significantly increased talar T1ρ values ([53.0 ± 7.4] mse ) compared to the healthy control subjects ([48.8 ± 4.1] msec) in the medial compartment. DATA CONCLUSION: Increased talar T1ρ relaxation times in CAI patients compared to healthy controls suggest that T1ρ relaxation is a sensitive biomarker for CAI-induced early-stage cartilage degeneration. However, the load-induced T1ρ change did not prove to be a viable marker for the altered biomechanical properties of the hyaline talar cartilage. LEVEL OF EVIDENCE: 2 LEVEL OF EFFICACY: Stage 2.

The role of sural nerve reflexes during drop-landing in subjects with and without chronic ankle instability.

The purpose of this study was to investigate the functional role of cutaneous reflexes during a single-leg drop-landing task among healthy, neurologically intact adults, and to identify whether individuals with chronic ankle instability (CAI) demonstrate altered reflexes and subsequent ankle kinematics. All subjects were physically active adults and were categorized as control (n = 10, Male = 6, Female = 4) or CAI (n = 9, Male = 4, Female = 5) depending on whether they scored a 0 or ≥ 11 on the Identification of Functional Ankle Instability questionnaire, respectively. Subjects performed 30-40 single-leg drop-landing trials from a platform set to the height of their tibial tuberosity. Muscle activity of four lower leg muscles was collected via surface electromyography, while ankle kinematics were recorded via an electrogoniometer. Non-noxious stimulations were elicited randomly to the ipsilateral sural nerve at two unique phases of the drop-landing task (takeoff and landing). Unstimulated and stimulated trials were used to calculate middle latency reflex amplitudes (80-120 ms) and net ankle kinematics (140-220 ms) post-stimulation. Mixed-factor ANOVAs were used to identify significant reflexes within groups and differences in reflex amplitudes between groups. Unlike the CAI group, the control group experienced significant facilitation of the Peroneus Longus (PL) and inhibition of the Lateral Gastrocnemius (LG) when stimulated at takeoff, resulting in eversion immediately prior to landing. When stimulated at landing, the control group experienced significantly more inhibition of the PL compared to the CAI group (p = 0.019). These results suggest lower neural excitability for individuals with CAI, which may predispose them to recurrent injury during similar functional tasks.

Systematic review of the methodological quality of patient-reported outcome measure for patients with chronic ankle instability.

OBJETIVE: Chronic ankle instability is generally associated with ankle sprain. Its consequences can be measured by means of patient-reported outcome measures (PROMs). The aim of this review is to identify the PROMs specifically available for chronic ankle instability and to evaluate their methodological quality and that of the cross-cultural adaptations made. DATA SOURCES: Papers were retrieved from PubMed, Embase, Scopus and Google Scholar databases, with no time limit applied, based on the following inclusion criteria: (1) type of participants: patients with chronic ankle instability, over 18 years of age; (2)type of study: those specifically focused on this pathology, using PROMs specific to chronic ankle instability and published in English; (3) type of outcome: measurement properties based on COSMIN criteria in patient-reported outcomes associated with chronic ankle instability. METHODS: This systematic review, following the COSMIN checklist, was conducted to determine the methodological quality of PROMs specific to foot and ankle pathologies, for patients presenting chronic ankle instability. RESULTS: Of the 576 studies identified in the initial search, 34 were included in the final analysis of measurement properties. Four - the Ankle Instability Instrument, the Chronic Ankle Instability Scale, the Cumberland Ankle Instability Tool and the Identification of Functional Ankle Instability - were original questionnaires, and the remaining 30 were cross-cultural adaptations. CONCLUSION: The Cumberland Ankle Instability Tool and the Identification of Functional Ankle Instability questionnaires can be useful instruments for evaluating chronic ankle instability, both in patients with this condition and also in non-pathological patients.

Balance training benefits chronic ankle instability with generalized joint hypermobility: a prospective cohort study.

BACKGROUND: Balance training is the first choice of treatment for chronic ankle instability (CAI). However, there is a lack of research on the effects of balance training in CAI with generalized joint hypermobility (GJH). This study is to compare the outcomes of balance training in CAI patients with and without GJH. METHODS: Forty CAI patients were assigned into the GJH group (Beighton ≥ 4, 20) and non-GJH group (Beighton < 4, 20) and they received same 3-month supervised balance training. Repeated measure ANOVA and independent t test were used to analyze self-reported questionnaires (Foot and ankle ability measure, FAAM), the number of patients experiencing ankle sprain, isokinetic muscle strength and postural control tests (Star excursion balance test, SEBT and Balance errors system, BES) before training, post-training immediately, and post-training 3 months, respectively. RESULTS: At baseline, no differences were found between groups with except for GJH group having poorer SEBT in the posteromedial direction (83.6 ± 10.1 vs 92.8 ± 12.3, %) and in the posterolateral direction (84.7 ± 11.7 vs 95.7 ± 8.7, %). Following the balance training, GJH group demonstrated lower re-sprain ratio (immediately after training, 11.1% vs 23.5%, 3 month after training, 16.7% vs 29.4%) than non-GJH group, as well as greater FAAM-S score, plantarflexion strength and dorsiflexion strength at post-training immediately and 3 months, and both groups improved similarly in the FAAM-A score, muscle strength and balance control (SEBT in the posterior-lateral and posterior-medial directions, and BES scores) compared with baseline. CONCLUSIONS: CAI patients with GJH gained equally even better postural stability and muscle strength after the balance training than the non-GJH patients. Balance training could still be an effective treatment for CAI patients with GJH before considering surgery. TRIAL REGISTRATION: ChiCTR1900023999, June 21st, 2019.

Effects of dual-task training on chronic ankle instability: a systematic review and meta-analysis.

BACKGROUND: Dual-task training has been a popular intervention for individuals with balance impairments. However, the effects of dual-task training on chronic ankle instability (CAI) have not been comprehensively analyzed and reliable clinical evidence is scarce. The purpose of this systematic review and meta-analysis is to evaluate the effectiveness of dual-task training on postural stability and functional ability in individuals with CAI. METHODS: PubMed, Web of Science, EBSCO, Cochrane Library, Physiotherapy Evidence Database (PEDro), and China National Knowledge Infrastructure (CNKI) were researched from inception to November 2022. This study was conducted by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Two reviewers assessed the studies for inclusion and extracted data. The Cochrane Risk of Bias list was used to assess the risk of bias in included studies. Mean differences (MD) with a 95% confidence interval (CI) were calculated with the RevMan 5.3 software. RESULTS: A total of 7 randomized controlled trials with 192 CAI met the inclusion criteria. The meta-analysis results showed that compared with the control group, dual-task training significantly improved the Y-balance test (MD = 1.60, 95% CI: -0.00 to 3.21, P = 0.050) and reduced COP-area (MD = - 0.94, 95% CI: -1.62 to - 0.26, P = 0.007) in individuals with CAI. However, there is no significant difference between dual-task training and the control group on COP-velocity (MD = - 0.26, 95% CI: -0.70 to 0.17, P = 0.240), hop test (MD = - 0.20, 95% CI: -0.66 to 0.26, P = 0.386) and BESS (MD = - 1.24, 95% CI: -2.95 to 0.48, P = 0.157) in individuals with CAI. CONCLUSION: This meta-analysis showed that dual-task training may be effective in improving static and dynamic postural stability. However, more high-quality randomized controlled trials are needed to verify the short and long-term effectiveness of dual-task training on CAI.

Arthroscopic Broström-Gould repair has comparable radiological and clinical outcomes compared to traditional open Broström-Gould repair in high-demand patients.

PURPOSE: This study sought to confirm whether traditional open Broström-Gould repair and arthroscopic Broström-Gould repair for chronic ankle instability (CAI) would produce comparable radiological and clinical outcomes in high-demand patients. METHODS: This retrospective case-cohort study included high-demand patients, as determined by a pre-injury Tegner Activity Level ≥ 6, who underwent Broström-Gould repair and were followed up for ≥ 2 years. Patients were divided into the arthroscopic Broström-Gould repair group (AS Group) and the open Broström-Gould repair group (Open Group). Perioperative radiological assessments were performed. The Tegner Activity Levels, Foot and Ankle Outcome Scores (FAOSs), Karlsson and Peterson (K-P) scores, and American Orthopaedic Foot and Ankle Society ankle-hindfoot (AOFAS) scores were evaluated clinically. RESULTS: A total of 65 patients (31 from the AS Group and 34 from the Open Group) were included in the study. There were no differences in age, sex, body mass index, preoperative anterior talar translation, talar tilt, signal-to-noise ratio, FAOS, K-P score, or AOFAS score between the two groups (n.s.). The preinjury median Tegner Activity Level was 7 and unchanged at the final follow-up in both groups. Postoperative stress radiographs showed improvement; however, the groups did not differ significantly. The FAOS, K-P scores, and AOFAS scores improved in each group (P < 0.001). However, the clinical scores did not differ between the groups (all n.s.). CONCLUSIONS: Traditional open and arthroscopic Broström-Gould repair for CAI in high-demand patients had comparable radiological and clinical outcomes. Clinically, arthroscopic Broström-Gould repair may represent a viable surgical alternative to open Broström-Gould repair in high-demand patients. LEVEL OF EVIDENCE: Level III.

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.

Arthroscopic all-inside ligament repair has similar or superior clinical outcomes compared to open repair for chronic ankle instability without concomitant intra-articular pathology at 5 years follow-up.

PURPOSE: Open ligament repair is widely considered the gold standard treatment for chronic ankle instability. Nevertheless, arthroscopic treatment of ankle instability has gained popularity becoming the preferred technique for many surgeons. This study aimed to compare the clinical outcomes of all-inside arthroscopic versus open lateral ligament repair for chronic ankle instability at 5 years follow-up. METHODS: Ninety consecutive patients were surgically treated for chronic ankle instability without concomitant intra-articular pathology observed on MRI: 41 patients [median age 28 (range 15-54) years] underwent an open lateral ligament repair (OLR); 49 patients [median age 30 (range 19-47) years] underwent an all-inside arthroscopic ligament repair (ALR). Functional outcomes using the Foot Functional Index (FFI), the American Orthopaedic Foot and Ankle Society (AOFAS) Hindfoot Score, and the Foot and Ankle Ability Measure-Sports Subscale (FAAM-SS) were assessed preoperatively and at the latest follow-up. At the latest follow-up, the satisfaction rate and complications were also recorded. RESULTS: The mean follow-up was 58 ± 17.6 (range 47-81) months. In both groups FFI, AOFAS and FAAM-SS score significantly improved compared to preoperative values (p < 0.001). There was no statistically significant difference in postoperative outcomes between groups in the AOFAS (n.s) and FAAM-SS (n.s), but the FFI results were significantly better in the ALR group (p < 0.05). No major complications were reported in either group. CONCLUSION: Open and arthroscopic ligament repair to treat chronic ankle instability without concomitant intra-articular pathology produced excellent comparable clinical outcomes at 5 years follow-up. The complications were minimal in both study groups with no significant differences in AOFAS and FAAM-SS scores. However, arthroscopic repair showed significantly better results on the FFI. Therefore, when treating chronic lateral ankle instability, surgeons should consider arthroscopic ligament repair. LEVEL OF EVIDENCE: III.

High body mass index is not a contraindication for an arthroscopic ligament repair with biological augmentation in case of chronic ankle instability.

PURPOSE: Obesity remains frequently mentioned as a contraindication for lateral ankle ligament repair. The aim of the study was to compare the clinical results of an arthroscopic lateral ligament repair with biological augmentation between patients with a body mass index (BMI) of more than 30 and less than 30. METHODS: Sixty-nine patients with an isolated lateral ankle instability were treated with an arthroscopic anterior talofibular ligament (ATFL) repair with biological augmentation using the inferior extensor retinaculum (IER). Patients were divided into two groups according to their BMI: ≥ 30 (Group A; n = 26) and < 30 (Group B; n = 43). Patients were pre-and post-operatively evaluated, with a minimum of 2 years follow-up, and using the Karlsson Score. Characteristics of the patients, complications, ankle instability symptoms recurrence, and satisfaction score were recorded. RESULTS: In group A, the median Karlsson Score increased from 43.5 (Range 22-72) to 85 (Range 37-100) at follow-up. Complications were observed in seven patients (27%). Nineteen patients (73%) reported that they were "very satisfied". One patient (4%) described persistent ankle instability symptoms. In group B, the median Karlsson Score increased from 65 (Range 42-80) to 95 (Range 50-100) at follow-up. Complications were observed in four patients (9%). Thirty-three patients (77%) reported that they were "very satisfied". Two patients (5%) described persistent ankle instability symptoms. Pre-operative and at last follow-up Karlsson Score, results were significantly different between the two groups. There was no significant statistical difference in favour of satisfaction score, complications and recurrence of ankle instability between the two groups. CONCLUSION: ATFL repair with biological augmentation using IER gives excellent results for patients with BMI ≥ 30. Compared to patients with BMI < 30, they present a slightly lower preoperative and postoperative Karlsson score, however, with a similar satisfaction rate, but are at higher risk of transient superficial peroneal nerve dysesthesia. LEVEL OF EVIDENCE: Level III.

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.