Calcaneofibular Ligament Research Articles

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

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. To determine the most accurate method to locate the calcaneofibular ligament (CFL) insertion radiographically. 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. 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. 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.

Risk Factors for the Recurrence of Instability After Lateral Ankle Ligament Repair.

Arthroscopic anterior talofibular ligament (ATFL) repair is widely performed for chronic lateral ankle instability (CLAI). Although many studies have reported excellent outcomes with this procedure, the recurrence of instability remains a common concern. Therefore, this study aimed to analyze the risk factors for the recurrence of instability after arthroscopic repair for CLAI. Fifty-six ankles of 53 patients with a mean age of 31.8 ± 14.7 years were retrospectively reviewed. All patients underwent arthroscopic ATFL repair. If instability remained immediately after ATFL repair, calcaneofibular ligament (CFL) repair was performed. The Ankle Activity Score (AAS) was assessed preoperatively, and clinical outcomes including the Japanese Society for Surgery of the Foot scale, Karlsson-Peterson scores, and the Self-Administered Foot Evaluation Questionnaire (SAFE-Q) were evaluated preoperatively and at the final follow-up. Talar tilt angle (TTA) was assessed preoperatively and 1 year postoperatively. Ankles were divided into 2 groups-nonrecurrence (postoperative TTA, <6 degrees) and recurrence (postoperative TTA, ≥6 degrees)-and clinical outcomes were compared. Sixteen ankles showed recurrent instability, whereas 40 did not. AAS, TTA, and social functioning in the SAFE-Q were significantly higher in the recurrence group than those in the nonrecurrence group preoperatively. In addition, the rate of poor ATFL remnant quality and the number of CFLs not repaired despite the preoperative injury diagnosis were significantly higher in the recurrence group than in the nonrecurrence group. Arthroscopic repair for ATFL and CFL deficiencies with preoperative high activity, poor remnant quality, and neglected CFL injury can result in the recurrence of instability. Appropriate surgical procedures to prevent the recurrence of instability should be selected for these ankles. Level IV, retrospective case series.

Treatment of lateral ankle instability patient-specific remnant approach.

Lateral ankle instability is one of the most common problems seen in the orthopaedic setting. Proper diagnosis is essential in order to provide the ideal treatment for these patients. All patients are subjected to nonoperative management in the form of functional rehabilitation. For those, however, who did not respond well to therapy, surgical treatment is then recommended. There are several surgical techniques available which have been meticulously studied and discussed in previous articles. The focus of this paper is on the author's perspective on choosing the surgical technique based on the quality of the anterior talofibular ligament and calcaneofibular ligament remnants. All patients are subjected to a diagnostic arthroscopy, where the remnant is assessed. The procedure then of doing an all-arthroscopic, open Modified Brostrom or anatomic reconstruction is then chosen based on this initial assessment.

The lateralization pattern has an influence on the severity of ankle sprains

Study design: Descriptive study. Background: Many risk factors contributing to ankle sprains have been studied in medical literature with coordination and balance being two of the major endogenous factors described. These are influenced by lateralization – a developmental and adaptive ability determined by the asymmetrical construction of the human brain, with cross-laterality referring to mixed limb dominance. Objectives: To determine whether cross lateralization is a risk factor for the severity of ligamentous injuries in ankle sprains since no data is yet available on such correlation. Methods: Two hundred forty-four patients with acute ankle sprains (136 men and 108 women) were prospectively evaluated between April 2006 and March 2009. The mean age was 30 (ranging from 18 to 76). Clinical and ultrasonographic examinations were performed on the study subjects. Laterality was then assessed by the Coren questionnaire and the AOFAS score was calculated. Patients with syndesmotic injuries and fractures were excluded from the study. Those qualified were divided into straight and crossed groups, according to their laterality type. Results: One hundred forty-four patients displayed straight lateralization, while cross-laterality was found in 100 subjects. Patients in the crossed group experienced more multi-ligamentous injuries than those in the straight group (p = 0.02). Following trauma, a higher AOFAS score was attributed to subjects that displayed a straight lateralization pattern, in comparison to subjects presenting with crossed laterality (p = 0.04). Conclusion: Crossed lateralization is associated with higher severity of ligament injuries in ankle sprains and may be considered a risk factor for calcaneofibular ligament injuries.

Role of the intrinsic subtalar ligaments in subtalar instability and consequences for clinical practice.

Subtalar instability (STI) is a disabling complication after an acute lateral ankle sprain and remains a challenging problem. The pathophysiology is difficult to understand. Especially the relative contribution of the intrinsic subtalar ligaments in the stability of the subtalar joint is still controversial. Diagnosis is difficult because of the overlapping clinical signs with talocrural instability and the absence of a reliable diagnostic reference test. This often results in misdiagnosis and inappropriate treatment. Recent research offers new insights in the pathophysiology of subtalar instability and the importance of the intrinsic subtalar ligaments. Recent publications clarify the local anatomical and biomechanical characteristics of the subtalar ligaments. The cervical ligament and interosseous talocalcaneal ligament seem to play an important function in the normal kinematics and stability of the subtalar joint. In addition to the calcaneofibular ligament (CFL), these ligaments seem to have an important role in the pathomechanics of subtalar instability (STI). These new insights have an impact on the approach to STI in clinical practice. Diagnosis of STI can be performed be performed by a step-by-step approach to raise the suspicion to STI. This approach consists of clinical signs, abnormalities of the subtalar ligaments on MRI and intraoperative evaluation. Surgical treatment should address all the aspects of the instability and focus on a restoration of the normal anatomical and biomechanical properties. Besides a low threshold to reconstruct the CFL, a reconstruction of the subtalar ligaments should be considered in complex cases of instability. The purpose of this review is to provide a comprehensive update of the current literature focused on the contribution of the different ligaments in the stability of the subtalar joint. This review aims to introduce the more recent findings in the earlier hypotheses on normal kinesiology, pathophysiology and relation with talocrural instability. The consequences of this improved understanding of pathophysiology on patient identification, treatment and future research are described.

Anatomic Basis of Ankle Instability

The surgeon must have a thorough understanding of ankle ligamentous anatomy in order to grasp new concepts including ankle microinstability and rotational instability. The anterior talofibular ligament (ATFL) has 2 fascicles, a superior fascicle which is intra-articular and an inferior fascicle which is extra-articular. Located within the ankle joint but extrasonovial, the superior fascicle of the ATFL lacks the capacity to heal after a moderate ankle sprain. Because this fascicle controls talar internal rotation, any deficiency may lead to ankle microinstability, which in turn may lead to chronic overloading of the deltoid ligament’s most anterior fascicles and chronic rotational instability. The ATFL inferior fascicle, the calcaneofibular ligament and their connecting fibers form the lateral fibulotalocalcaneal ligament complex. An injury of the lateral fibulotalocalcaneal ligament complex will lead to classic chronic ankle instability. These new findings on the ankle ligaments have major implications for ankle instability. Level of Evidence: Diagnostic Level V — expert opinion. See Instructions for Authors for a complete description of levels of evidence.

Adaptation of the Signal Noise Quotient MRI classification for graft ligamentization analysis following ATFL and CFL anatomical reconstruction: Validation of the SNQA

BackgroundChronic ankle instability is the most frequent clinical sign of an antero tibiofibular (ATFL) and/or calcaneo fibular ligament (CFL) tear. One common surgical technique is to use the distal tendon of the gracilis muscle to reconstruct both the ATFL and CFL. In the knee, the hamstring tendons used in anterior cruciate ligament (ACL) reconstruction may go through structural modifications called "ligamentization ". A noninvasive MRI technique has been developed using the Signal/Noise Quotient to compare the signal of the graft following reconstruction to that of the posterior cruciate ligament. To our knowledge no studies have ever evaluated radiographic changes in the graft over time. The main goal of this study was to develop a specific MRI protocol to evaluate graft remodeling following ATFL and CFL reconstruction over time. MethodsA prospective study of the changes in the MRI signal of the ATFL-CFL graft 3-months postoperatively was performed in 20 patients. The main outcome was a comparison of the graft signal to that of the peroneal fibular tendon and the surrounding noise to determine the Ankle SNQ (SNQA). MRI images were evaluated by two senior radiologists to assess inter-rater reliability and then 2 weeks later for the intra-rater reproducibility. ResultsThe intraclass correlation (ICC) showed excellent inter- and intra rater reliability for the ATFL SNQA (0.96 and 0.91, respectively); and for the CFL SNQA, the ICC was 0.97 and 0.99, respectively. Bland-Altman analysis showed very limited bias in the interpretation of SNQA. ConclusionThis preliminary study confirmed the inter- and intra- rater reliability of a new tool using the SNQA.

Deep learning-assisted classification of calcaneofibular ligament injuries in the ankle joint

The classification of calcaneofibular ligament (CFL) injuries on magnetic resonance imaging (MRI) is time-consuming and subject to substantial interreader variability. This study explores the feasibility of classifying CFL injuries using deep learning methods by comparing them with the classifications of musculoskeletal (MSK) radiologists and further examines image cropping screening and calibration methods. The imaging data of 1,074 patients who underwent ankle arthroscopy and MRI examinations in our hospital were retrospectively analyzed. According to the arthroscopic findings, patients were divided into normal (class 0, n=475); degeneration, strain, and partial tear (class 1, n=217); and complete tear (class 2, n=382) groups. All patients were divided into training, validation, and test sets at a ratio of 8:1:1. After preprocessing, the images were cropped using Mask region-based convolutional neural network (R-CNN), followed by the application of an attention algorithm for image screening and calibration and the implementation of LeNet-5 for CFL injury classification. The diagnostic effects of the axial, coronal, and combined models were compared, and the best method was selected for outgroup validation. The diagnostic results of the models in the intragroup and outgroup test sets were compared with those results of 4 MSK radiologists of different seniorities. The mean average precision (mAP) of the Mask R-CNN using the attention algorithm for the left and right image cropping of axial and coronal sequences was 0.90-0.96. The accuracy of LeNet-5 for classifying classes 0-2 was 0.92, 0.93, and 0.92, respectively, for the axial sequences and 0.89, 0.92, and 0.90, respectively, for the coronal sequences. After sequence combination, the classification accuracy for classes 0-2 was 0.95, 0.97, and 0.96, respectively. The mean accuracies of the 4 MSK radiologists in classifying the intragroup test set as classes 0-2 were 0.94, 0.91, 0.86, and 0.85, all of which were significantly different from the model. The mean accuracies of the MSK radiologists in classifying the outgroup test set as classes 0-2 were 0.92, 0.91, 0.87, and 0.85, with the 2 senior MSK radiologists demonstrating similar diagnostic performance to the model and the junior MSK radiologists demonstrating worse accuracy. Deep learning can be used to classify CFL injuries at similar levels to those of MSK radiologists. Adding an attention algorithm after cropping is helpful for accurately cropping CFL images.

The delta-snook ankle ligament reconstruction for combined deltoid insufficiency and lateral ankle instability

BackgroundAnkle sprains are one of the most common injuries amongst the general population and affect all spectrums of activity levels. While the anterior talofibular and calcaneal fibular ligaments are most prevalently injured during sprains there are instances when chronic lateral ankle instability leads to rotational ankle instability and attenuate the deltoid ligament. The few literature that exists concerning lateral and medial ankle ligament reconstruction focus on an arthroscopic approach. AimThe goal of this current work is to describe a novel open surgical reconstruction of the lateral collateral ligaments and anterior deltoid through a coupled repair. Surgical TechniqueA singular semitendinosus allograft is utilized to reconstruct the anterior deltoid, anterior talofibular and calcaneofibular ligaments. Canals are reamed for anchoring of the allograft through the medial malleolus, anterior talar body, distal fibula, and midline calcaneus. The anterior talar body, distal fibula and midline calcaneus are reamed fully to allow for pull through technique of the allograft. The medial malleolus and talar neck are anchored first, followed by the anterior fibula, and lastly the lateral calcaneus. All anchoring is performed with the ankle in a neutral position. ConclusionThis work successfully describes a novel open surgical reconstruction of the lateral collateral ligaments and anterior deltoid through a coupled repair. This technique affords the surgeon greater control over the final product and allows for a repair in a neutral position. The semitendinosus allograft also allows for a more anatomic repair with less incidence of stiffening at the ankle joint. The authors’ have noted good results and return to full activity for the patients that have undergone this procedure.

Radiological features accompanying peroneus brevis split rupture revealed on magnetic resonance imaging – a cohort study

BackgroundPeroneal split tears are an underrated cause of ankle pain. While magnetic resonance imaging (MRI) is useful for diagnosis, split tears are challenging to identify. The aim of the study was to investigate the association of peroneus brevis split rupture with abnormalities of the superior peroneal retinaculum (SPR), anterior talofibular ligament (ATFL), calcaneofibular ligament (CFL), joint effusion, morphology of the malleolar groove, presence of the bone marrow oedema and prominent peroneal tuberculum.MethodsAnkle MRI cases were assessed by independent observers retrospectively in two groups: one with peroneus brevis split tears (n = 80) and one without (control group, n = 115). Two observers evaluated the soft tissue lesions, and three graded the bone lesions. Fisher’s exact test and Pearson correlation were used for analysis. The Bonferroni-Holm method (B-H) was used to adjust for multiple comparisons.ResultsOnly bone marrow edema in the posterior part of the lateral malleolus was significantly (p < 0.05) more common in the split tear group after applying B-H. SPR total rupture was seen only in the experimental group. No differences in incidence of ATFL and CFL lesions or other SPR lesions were noticed (p < 0.05).ConclusionBone marrow edema in the posterior part of the lateral malleolus is associated with peroneus split tears on MRI.

Individual fascicles of the ankle lateral ligaments and the lateral fibulotalocalcanealligament complex can be identified on 3D volumetric MRI.

Lateral ligament ankle sprains are common and the anatomy on imaging studies is vital for accurate diagnosis. The lateral fibulotalocalcaneal ligament (LFTCL) complex consists of the inferior fascicle of the anterior talofibular ligament (ATFL) which is connected by arciform fibres with the calcaneofibular ligament (CFL). The superior fascicle of ATFL is an independent structure that should be assessed individually. MRI evaluation of these distinct fascicles and the arciform fibres has not been described. The aim of this study is to identify the anatomical relationship of these components of the LFTCL complex in healthy individuals on MRI. Thirty ankles from healthy volunteers were imaged using 3D volumetric MRI. The ATFL fascicles and size were evaluated. Presence of arciform fibres connecting the inferior ATFL fascicle and CFL to form the LFTCL complex and anatomical relationship around the lateral ligament complex were assessed. Both the superior and inferior ATFL fascicles were observed in 26 (86.7%) ankles. The superior ATFL fascicle was significantly larger in all specimens (39% longer and 80.7% wider). For the specimens with a single fascicle, this was similar in size to the superior fascicle observed in the other 26 specimens. These measurements were not affected by age or gender. Arciform fibres of the LFTCL complex were identified in 22 (84.6%) specimens with two ATFL fascicles and three (75%) ankles with a single ATFL fascicle. Connecting fibres from the ATFL to PTFL were observed in 19 (63.3%) ankles while connections between the CFL and PTFL were identified in 21 (70%) ankles. Five ankles had a perforating artery visualized in the intervening space between the superior and inferior ATFL fascicles (a branch of the lateral tarsal artery of the dorsalis pedis artery). Two distinct ATFL fascicles may be identified in the majority of ankles on MRI. Isolated injury to the superior fascicle identified on MRI may be useful when diagnosing patients presenting with symptoms of subtle instability without overt ankle laxity on clinical examination. The current study is the first to identify the arciform fibres of the LFTCL complex supporting isolated ATFL repair in the presence of intact LFTCL complex. Level III.

Mouse model of subtalar post-traumatic osteoarthritis caused by subtalar joint instability

BackgroundCommon ankle sprains are often accompanied by injury to the subtalar joint, which eventually leads to subtalar joint instability. Because the clinical manifestations for subtalar joint instability are similar to ankle joint injuries, these are often overlooked. This study aimed to establish an animal model of subtalar joint instability to study post-traumatic osteoarthritis of the subtalar joint caused by long-term subtalar joint instability and to provide a reference for future clinical research on chronic subtalar joint instability.MethodsIn all, 24 C57BL/6 male mice were randomly divided into three groups: Sham, cervical ligament (CL) transection and CL + calcaneofibular ligament (CFL) transection groups. One week after surgical operation, all mice were trained to run in the mouse rotation fatigue machine every day. During this period, a balance beam test was used to evaluate the motor level and coordination ability of the mice before the operation and three days, one week, four weeks, eight weeks, and twelve weeks after operation. Further, post-traumatic osteoarthritis of the subtalar joint was quantified via micro-CT and histological staining.ResultsThe mice in the partial ligament transection group took significantly longer than those in the Sham group to pass through the balance beam and showed an increased number of hindfoot slips. Micro-CT analysis showed that the subtalar bone volume fraction in the CL + CFL transection group and CL transection group was 5.8% and 2.8% higher than that in the Sham group, respectively. Histological staining showed obvious signs of post-traumatic osteoarthritis (PTOA) in the subtalar joint of the ligament transection group.ConclusionsThe transection of CL and CL + CFL can cause instability of the subtalar joint in mice, resulting in a decrease in motor coordination, and long-term instability of the subtalar joint in mice can cause PTOA of the subtalar joint, which is manifested as destruction and loss of articular cartilage.

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

BackgroundLigament 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. MethodsThirty-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. ResultsThe 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). ConclusionsThe SIR is useful for evaluating the quality of the ATFL and CFL, which enables the decision of the treatment strategy of the CLAI.

Calcaneofibular ligament may act as a tensioner of peroneal tendons as revealed by a contactless three-dimensional scan system on cadavers

The ligaments are believed to have a role in stabilizing joints and regulating joint motion. Here, we propose a novel function of the calcaneofibular ligament (CFL), which stabilizes the ankle joint. In human bipedal locomotion, the peroneal muscles maintain mediolateral stability and prevent involuntary ankle inversion. To investigate the functional relationship between the peroneal longus tendon (PLT), brevis tendon (PBT), and CFL, we quantitatively analyzed the positional changes of the tendons by using a contactless three-dimensional optical scan system. Eighteen cadaveric specimens were included in the study. Interestingly, with increased tension of the CFL, the tendons significantly moved toward the lateral direction (P < 0.001), compared with their position when the CFL was detached. The actual lift amount reached 2.0 ± 0.8 mm for the PLT and 1.9 ± 1.0 mm for the PBT. These results strongly suggest that a tensed CFL can lift the peroneal tendons and may act as a “tensioner” for the effective transmission of muscle contraction. This phenomenon contributes to postural control, especially in regaining balance on uneven terrain, and provides a new perspective for the exercise methods or understanding the ankle joint instability due to sprains.

Connecting Fibers Between ATFL's Inferior Fascicle and CFL Transmit Tension Between Both Ligaments

Category: Basic Sciences/Biologics; Ankle Introduction/Purpose: The lateral ligament complex of the ankle has been extensively studied. Recently an anatomical study described a connection between anterior talofibular ligament inferior fascicle (ATFLif) and calcaneofibular ligament (CFL). The applicability and the mechanical role of these connections have not yet been studied and need to be clarified. The purpose of this study is to evaluate the connection between ATFLif and CFL through a dynamic measurement analysis. Methods: An anatomical study was performed in 13 fresh-frozen below-the-knee ankle specimens. Each specimen was dissected in a protocolized manner until the lateral ligaments were exposed. A complete injury to both ATFL's fascicles was created in the proximal third of the ligament. A displacement transducer specifically design was inserted in the CFL and in the lateral part of the calcaneus to test its lengthening. A traction of 1 kg weight (9.8 N) was applied to ATFLif while the transducer measured the lengthening that this force created in the CFL. Results: A total of 13 ankle specimens were carefully dissected. One specimen with signals of a prior traumatic injury of the ATFLif was excluded. A total of 12 specimens were included, 7 females and 5 males with an average age of 74 years (52-88 years). The right ankle was dissected in 6 specimens. ATFL was identified as a two-fascicled ligament in all cases. The fibers connecting the ATFLif and CFL were observed in all specimens. The displacement transducer showed lengthening in the CFL in all measurements with a median of 0.59 mm (SD 0.34). Conclusion: Connecting fibers between ATFLif and CFL are robust enough to transmit tension from one structure to the other.In the case of associated proximal lesions of the ATFLif and CFL, ligaments repair with a single suture may be considered. This can be applied in surgical procedures in patients with lateral ankle instability.

3D Light Scanner Analysis of the Lateral Collateral Ligaments of the Ankle: An Anatomical Study

Category: Basic Sciences/Biologics; Ankle Introduction/Purpose: Recently an anatomical study described a medial connection between the anterior talofibular ligament inferior fascicle (ATFLif), calcaneofibular ligament (CFL) and posterior talofibular ligament (PTFL). Therefore, there is no research evaluating the lateral ligaments and their relationships through a three-dimensional view achieved by a digital marking of their foot prints. The authors hypothesize that a three-dimensional analysis made only by an accurately digital analysis can clarify the lateral collateral ligaments (LCL) connections and their foot prints relations. This work aims to carry out an anatomical study in cadaveric pieces in which the lateral ankle ligaments were dissected and evaluated by a tridimensional scanner that allows a digitally and three-dimensional assessment of their foot prints and connections. Methods: An anatomical study was performed in 11 fresh-frozen ankle specimens. Each ankle was dissected to achieve the amputation of the calcaneus, talus and fibula, keeping the inserts of the footprints of LCL. After that, each bone piece with the insertion remnants of the LCL was submitted to an evaluation by a scanner machine. Surface scans for these bones were collected using a structured light scanner. Each bone piece was set on a 3D automatic turntable to capture a 360° scan and was scanned in two orientations, with 6 scans per orientation. Finally, all the scans were aligned and final fused models were created using the HP DAVID software package and exported to a wavefront 3D object file. The 3D models were imported into Geomagic Studio to calculate surface area of the LCL foot prints. Results: A total of 11 units of each, talus, fibula and calcaneus were dissected from 11 ankles specimens. The ATFL was identified as a two-fascicled ligament and the fibers connecting fibers between the ATFLif and CFL was present in all specimens. In two talus there was only one insertion of the ATFL. After scanning the bones, the authors observed that the foot prints of ATFLif, CFL and PTFL were contiguous at medial side of the fibula, with an average of the surface area of 486,7 mm2. The foot print of the CFL on the calcaneus was located at the junction of a vertical line tangent to the highest point of the posterior subtalar with a horizontal line extending from the sinus tarsi in all specimens. Conclusion: This study demonstrated by a 3D analysis that the LCL of the ankle share the same foot print at medial side on the fibula and are all connected since the foot prints of the ATFL inf, CFL and PTFL were contiguous. In the case of associated proximal lesions of the ATFLif and CFL, ligaments repair with a single suture may be considered. This can be applied in surgical procedures in patients with lateral ankle instability.fig

Role of Syndesmotic Ligaments in Lateral Ankle Instability

Category: Ankle; Sports; Trauma Introduction/Purpose: Despite the success of surgical intervention, about 13-35% of patients continue to have ankle symptoms after surgery for lateral ankle instability which could be due to presence of undetected and thus untreated injury to other ankle ligaments.Concomitant lateral ankle ligament and syndesmotic ligamentous injuries are common. It is unknown, however, whether syndesmotic ligaments directly contribute to lateral ankle stability. Therefore, the aim of this study was to fluoroscopically evaluate whether the syndesmotic ligaments contributes to lateral ankle stability. Methods: Twenty-four above-knee cadaveric specimens were divided into three groups that underwent fluoroscopic evaluation for lateral ankle stability. In all the groups, the assessment was first done with all syndesmotic and ankle ligaments intact. Thereafter, Group 1 underwent sequential transection of the lateral ankle ligaments: (1) anterior talofibular ligament (ATFL), (2)calcaneofibular ligament(CFL), and (3)posterior talofibular ligament (PTFL). Group 2 underwent sequential transection of the lateral ankle ligaments followed by the syndesmotic ligaments: (1) ATFL, (2) CFL, (3) PTFL, (4) anterior inferior tibiofibular ligament(AITFL), (5)interosseous ligament(IOL), and (6)posterior inferior tibiofibular ligament (PITFL). Group 3 alternating and sequential transection of the syndesmotic and lateral ankle ligaments: (1) AITFL, (2) ATFL, (3) CFL, (4) IOL, (5) PTFL, and (6) PITFL. In all scenarios, three loading conditions were considered:(1)An anterior drawer test at 50N and 80N of direct force, (2) talar tilt under 1.7Nm torque, and (2) lateral clear space (LCS) under 1.7Nm torque. Wilcoxon rank-sum test was used to compare the findings of each ligamentous transection state to the intact state. Results: The lateral ankle remained stable after transection of all syndesmotic ligaments (AITFL, IOL, PITFL). However, after additional transection of the ATFL, the lateral ankle became unstable in varus and anterior drawer testing conditions (p-values ranging from 0.036-0.012). Lateral ankle instability was also observed after transection of the ATFL and AITFL (p-values ranging from 0.036-0.012). Subsequent transection of the CFL worsened the lateral ankle instability. Conclusion: Our findings suggest that syndesmotic injuries can destabilize otherwise stable lateral ankle sprains. When treating lateral ankle instability, clinician should maintain a lower threshold for operative intervention for syndesmotic stabilization if there are any residual symptoms over the AITFL.

Traditional Modified Brostrom vs Suture Tape Ligament Augmentation for Chronic Lateral Ankle Instability: A Cost-Effectiveness Analysis

Category: Sports; Ankle; Other Introduction/Purpose: Surgical treatment of chronic lateral ankle instability (CLAI) with the Modified Brostrom-Gould (MB) procedure and suture tape ligament augmentation (+ST) has proven to be biomechanically and clinically successful. A concern regarding the MB + ST procedure is increased surgical costs and additional operating room time. To date, there are no available studies in the literature evaluating the cost-effectiveness of suture tape ligament augmentation of the Modified Brostrom-Gould procedure. The purpose of the present study is to evaluate and report the cost-effectiveness of the Modified Brostrom-Gould procedure, with and without suture tape ligament augmentation. Methods: This study followed the consensus-based recommendations made by the Panel on Cost-Effectiveness in Health and Medicine. The base case was assumed to be a healthy individual with symptomatic CLAI following recurrent ankle sprains requiring surgical intervention. The standard MB technique utilized two 2.4 mm BioComposite SutureTak anchors for direct anatomic repair of the disrupted anterior talofibular and calcaneofibular ligaments. This treatment was then compared to the Modified Brostrom-Gould procedure with the addition of suture tape ligament augmentation (MB + ST). A Markov Model was designed to evaluate the cost-effectiveness of the MB + ST procedure. Model input variables and parameters were derived from a prospective randomized clinical study which described the rate of return to previous activity level at 26 weeks postoperatively for the MB and MB + ST groups. Direct and indirect surgical costs were incorporated into the model to provide an accurate financial assessment of both procedures. Results: When only direct surgical costs were considered, the total cost of MB was $2,318.88 and the total effectiveness was 0.91 quality-adjusted-life-years (QALY) over the 26-week period. The total cost for MB + ST was $4,004.93 and the total effectiveness was 0.98 QALY's. Patients in the MB + ST group spent, on average, $1,686 more than those in the MB group, with a higher quality of life by 0.07 QALYs. To evaluate the impact of indirect surgical costs, a sensitivity analysis was performed which measured the additional costs associated with physical therapy and time off work. Patients in the MB group incurred an increased physical therapy cost of $4,212 assuming 4.2 extra weeks of treatment. Assuming those in the MB group returned to full duty work 4.2 weeks later than those in the MB + ST group, this resulted in a net loss of approximately $5,413.80 in wages. Conclusion: In the early postoperative period following lateral ligament reconstruction for CLAI, MB + ST technique yields a higher quality of life and lower overall expense despite a higher direct surgical cost when compared to MB alone. The cost effectiveness of the MB + ST technique was further supported through a sensitivity analysis which revealed that as indirect surgical costs were incorporated into the model, MB + ST became an even more cost effective option. This cost-effectiveness analysis adds to the growing literature in support of suture tape augmentation for the Modified Brostrom-Gould procedure.

A new mouse model of ankle instability induced by multiple mechanical sprains with controlled inversion angle and speed.

Ankle sprain occurs by a sudden and extreme inversion and plantarflexion at the ankle joint to cause ligamentous injuries. A portion of ankle sprain patients experience recurrent ankle sprains and develop chronic ankle instability (CAI). The present CAI animal models are single events with severe ligamentous injury using surgical transection of ligaments or manually overextending the ankle. Purpose: To simulate the mechanical and recurrent sprain injuries in CAI patients, we established a new ankle instability model with multiple ankle injuries using a self-designed machine to sprain the ankle with a controlled inversion angle and speed. Methods: Male C57BL/6J mice were used and respectively subjected to a sham operation, calcaneofibular ligament (CFL) transection, and mechanical ankle sprains. Three mechanical sprains were performed on the 13th and 185th day after the initial mechanical ankle sprain. Results: The first mechanical sprain and CFL transection induced ankle injury as indicated by an average of a 62% decrease in ankle pressure pain threshold and a 114% increase in the ankle thickness compared with the contralateral untreated ankle. The second and third mechanical sprains induced recurrent ankle injuries. The foot slips during beam tests were increased after mechanical ankle sprains but not after CFL transection, indicating the induction of motor balance deficits. Multiple mechanical ankle sprains induced significant gait changes in longer duration of stance (an average of 194% increase), swing (134%), and step cycle (147%) compared with CFL transection or sham operation, and slower walking speed (78% reduction) and shorter step distance (91%) after the third sprain. Conclusion: These results elucidate that multiple mechanical sprains, which induce recurrent ankle injuries, balance deficits, and gait changes, are a good model for investigating the mechanisms of CAI induced by recurrent sprain injuries.

Fluoroscopic Evaluation of the Role of Syndesmotic Injury in Lateral Ankle Instability in a Cadaver Model.

There is a high prevalence of concomitant lateral ankle ligament injuries and syndesmotic ligamentous injuries. However, it is unclear whether syndesmotic ligaments directly contribute toward the stability of the lateral ankle. Therefore, the aim of this study was to fluoroscopically evaluate the role of the syndesmotic ligaments in stabilizing the lateral ankle. Twenty-four cadaveric specimens were divided into 3 groups and fluoroscopically evaluated for lateral ankle stability with all syndesmotic and ankle ligaments intact and then following serial differential ligamentous transection. Group 1: (1) anterior talofibular ligament (ATFL), (2) calcaneofibular ligament (CFL), and (3) posterior talofibular ligament (PTFL). Group 2: (1) anterior inferior tibiofibular ligament (AITFL), (2) interosseous ligament (IOL), (3) posterior inferior tibiofibular ligament (PITFL), (4) ATFL, (5) CFL, and (6) PTFL. Group 3: (1) AITFL, (2) ATFL, (3) CFL, (4) IOL, (5) PTFL, and (6) PITFL. At each transection state, 3 loading conditions were used: (1) anterior drawer test performed using 50 and 80 N of direct force, (2) talar tilt <1.7 Nm torque, and (2) lateral clear space (LCS) <1.7 Nm torque. These measurements were in turn compared with those of the stressed intact ligamentous state. Wilcoxon rank-sum test was used to compare the findings of each ligamentous transection state to the intact state. A P value <.05 was considered statistically significant. The lateral ankle remained stable after transection of all syndesmotic ligaments (AITFL, IOL, PITFL). However, after additional transection of the ATFL, the lateral ankle became unstable in varus and anterior drawer testing conditions (P values ranging from .036 to .012). Lateral ankle instability was also observed after transection of the ATFL and AITFL in varus and anterior drawer testing conditions (P values ranging from .036 to .012). Subsequent transection of the CFL and PTFL worsened the lateral ankle instability. Our findings suggest that isolated syndesmosis disruption does not result in lateral ankle instability. However, the lateral ankle became unstable when the syndesmosis was injured along with ATFL disruption. When combined with ATFL release, disruption of the syndesmosis appeared to destabilize the lateral ankle.