Ankle Injuries During Excessive External Foot Rotation May Depend on Foot Constraint: Development of a Computational Model

2010 ◽  
Author(s):  
Feng Wei ◽  
John W. Powell ◽  
Roger C. Haut
Keyword(s):  
Computational Model ◽  
Bone Fracture ◽  
Clinical Studies ◽  
External Rotation ◽  
Ankle Injuries ◽  
Deltoid Ligament ◽  
Calcaneofibular Ligament ◽  
Tibiofibular Ligament ◽  
Posterior Talofibular Ligament

Numerous studies on the mechanisms of ankle injury deal with injuries to the syndesmosis and anterior ligamentous structures, but previous sectioning and clinical studies also describe the important role of the posterior talofibular ligament (PTaFL) in the ankle’s resistance to external rotation of the foot. Foot constraint may influence subtalar motion and the movement of the bones in the foot, thereby influencing the mode of injury during external rotation [1]. Stiehl et al. [2] constrain the foot with fiberglass cast tape, externally rotate the foot 90°, and produce injury to the deltoid ligament and anterior tibiofibular ligament (ATiFL) with bone fracture. In contrast, Stormont et al. [3] fix the foot in a potting alloy and conclude the primary ligamentous restraints to external rotation are the PTaFL and calcaneofibular ligament (CaFL).

scholarly journals Diagnostic value of ultrasonography in acute lateral and syndesmotic ligamentous ankle injuries

2020 ◽  
Author(s):  
Thomas P. A. Baltes ◽  
Javier Arnáiz ◽  
Liesel Geertsema ◽  
Celeste Geertsema ◽  
Pieter D’Hooghe ◽  
...  
Keyword(s):  
External Rotation ◽  
Diagnostic Value ◽  
Ankle Injuries ◽  
Anterior Talofibular Ligament ◽  
Neutral Position ◽  
Post Injury ◽  
Calcaneofibular Ligament ◽  
Tibiofibular Ligament ◽  
Anterior Inferior Tibiofibular Ligament ◽  
Dynamic Ultrasound

Abstract Objectives To determine the diagnostic value of ultrasonography for complete discontinuity of the anterior talofibular ligament (ATFL), the calcaneofibular ligament (CFL) and the anterior inferior tibiofibular ligament (AITFL). Methods All acute ankle injuries in adult athletes (> 18 years old) presenting to the outpatient department of a specialised Orthopaedic and Sports Medicine Hospital within 7 days post-injury were assessed for eligibility. Using ultrasonography, one musculoskeletal radiologist assessed the ATFL, CFL and AITFL for complete discontinuity. Dynamic ultrasound measurements of the tibiofibular distance (mm) in both ankles (injured and contralateral) were acquired in the neutral position (N), during maximal external rotation (Max ER), and maximal internal rotation (Max IR). MR imaging was used as a reference standard. Results Between October 2017 and July 2019, 92 acute ankle injuries were included. Ultrasound diagnosed complete discontinuity of the ATFL with 87% (CI 74–95%) sensitivity and 69% (CI 53–82%) specificity. Discontinuity of the CFL was diagnosed with 29% (CI 10–56%) sensitivity and 92% (CI 83–97%) specificity. Ultrasound diagnosed discontinuity of the AITFL with 100% (CI 74–100%) sensitivity and 100% (CI 95–100%) specificity. Of the dynamic measurements, the side-to-side difference in external rotation had the highest diagnostic value for complete discontinuity of the AITFL (sensitivity 82%, specificity 86%; cut-off 0.93 mm). Conclusions Ultrasound has a good to excellent diagnostic value for complete discontinuity of the ATFL and AITFL. Therefore, ultrasound can be used to screen for injury of the ATFL and AITFL. Compared with ultrasound, dynamic ultrasound has inferior diagnostic value for complete discontinuity of the AITFL. Key Points • Ultrasound has a good to excellent diagnostic value for complete discontinuity of the anterior talofibular ligament (ATFL) and anterior inferior tibiofibular ligament (AITFL). • Ultrasound can be used to screen for injury of the ATFL and AITFL. • Compared with ultrasound, dynamic ultrasound has inferior diagnostic value for complete discontinuity of the AITFL.

Impact of Torque on Assessment of Syndesmotic Injuries Using Weightbearing Computed Tomography Scans

2019 ◽  
Vol 40 (6) ◽  
pp. 710-719 ◽  
Author(s):  
Nicola Krähenbühl ◽  
Travis L. Bailey ◽  
Maxwell W. Weinberg ◽  
Nathan P. Davidson ◽  
Beat Hintermann ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Axial Load ◽  
External Rotation ◽  
Ct Scans ◽  
Deltoid Ligament ◽  
Tibiofibular Syndesmosis ◽  
Tibiofibular Ligament ◽  
Distal Tibiofibular Syndesmosis ◽  
Axial Ct ◽  
The Impact

Background: The diagnosis of subtle injuries to the distal tibiofibular syndesmosis remains elusive. Conventional radiographs miss a large subset of injuries that present without frank diastasis. This study evaluated the impact of torque application on the assessment of syndesmotic injuries when using weightbearing computed tomography (CT) scans. Methods: Seven pairs of male cadavers (tibia plateau to toe-tip) were included. CT scans with axial load application (85 kg) and with (10 Nm) or without torque to the tibia (corresponding to external rotation of the foot and ankle) were taken during 4 test conditions. First, intact ankles (native) were scanned. Second, 1 specimen from each pair underwent anterior inferior tibiofibular ligament (AITFL) transection (condition 1A), while the contralateral underwent deltoid transection (condition 1B). Third, the lesions were reversed on the same specimens and the remaining intact deltoid or AITFL was transected (condition 2). Finally, the distal tibiofibular interosseous membrane (IOM) was transected in all ankles (condition 3). Measurements were performed to assess the integrity of the distal tibiofibular syndesmosis on digitally reconstructed radiographs (DRRs) and on axial CT scans. Results: Torque impacted DRR and axial CT scan measurements in almost all conditions. The ability to diagnose syndesmotic injuries using axial CT measurements improved when torque was applied. No significant syndesmotic morphological change was observed with or without torque for either isolated AITFL or deltoid ligament transection. Discussion: Torque application had a notable impact on two-dimensional (2-D) measurements used to diagnose syndesmotic injuries for both DRRs and axial CT scans. Because weightbearing conditions allow for standardized positioning of the foot while radiographs or CT scans are taken, the combination of axial load and torque application may be desirable. Clinical Relevance: Application of torque to the tibia impacts 2-D measurements and may be useful when diagnosing syndesmotic injuries by DRRs or axial CT images.

scholarly journals Displacement of Sequential Syndesmotic Ankle Injuries Assessed by a 3D Weightbearing CT

2019 ◽  
Vol 4 (4) ◽  
pp. 2473011419S0012
Author(s):  
Arne Burssens ◽  
Nicola Krähenbühl ◽  
Hannes Vermue ◽  
Nathan Davidson ◽  
Maxwell Weinberg ◽  
...  
Keyword(s):  
External Rotation ◽  
Imaging Techniques ◽  
Pearson Correlation ◽  
Ankle Injuries ◽  
Deltoid Ligament ◽  
3D Analysis ◽  
Anatomical Landmarks ◽  
Posterior Translation ◽  
2D Imaging ◽  
Weightbearing Ct

Category: Ankle Introduction/Purpose: Syndesmotic ankle injuries are challenging to diagnose, since current 2D imaging techniques try to quantify a 3D displacement. Therefore, our aim was two-fold: to determine displacement of sequential syndesmotic ankle injuries under various amounts of load using a 3D weightbearing CT (WBCT) and to assess the relation with current 2D imaging. Methods: Seven paired male cadaver specimens were included (tibia plateau to toe-tip) and mounted into a custom-built frame. WBCT scans were obtained after different patterns of load (0 kg or 85 kg) were combined with torque (0 Nm or 10 Nm external rotation). These conditions were repeated after each ligament condition: intact ligaments, sequential sectioning of the anterior inferior tibiofibular ligament (AITFL), deltoid ligament (DL), and interosseous membrane (IOM). CT images were segmented to obtain 3D models. These allowed quantification of displacement based on the position of computed anatomical landmarks in reference to the intact position of the fibula. A correlation analysis was performed between the 2D and 3D measurements. Results: The effect of torque caused significant displacements in all directions (P<0.05), except for shortening of the fibula (P>0.05). Weight caused a significant lateral (mean=-1.4 mm, SD=1.5) and posterior translation (mean=-0.6 mm, SD=1.8). The highest displacement consisted of external rotation (mean=-9.4°, SD=6.5) and posterior translation (mean=6.1 mm, SD=2.3) after IOL sectioning combined with torque (Fig. 1). Pearson correlation coefficients were moderate (range 0.31-0.51, P<0.05). Conclusion: Torque demonstrated superiority over weight in detecting syndesmotic ankle instability after 3D analysis. The clinical relevance of these findings can improve diagnosis by incorporating rotatory platforms during imaging and treatment strategies by providing appropriate stabilization against rotation.

Finite Element Analysis of Fixed Medial Malleolar Fractures

2013 ◽  
Author(s):  
Ruchi D. Chande ◽  
John R. Owen ◽  
Robert S. Adelaar ◽  
Jennifer S. Wayne
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Mechanical Performance ◽  
External Rotation ◽  
Weight Bearing ◽  
High Stress ◽  
Ankle Injuries ◽  
Deltoid Ligament ◽  
Medial Malleolus ◽  
Element Analysis

The ankle joint, comprised of the distal ends of the tibia and fibula as well as talus, is key in permitting movement of the foot and restricting excessive motion during weight-bearing activities. Medial ankle injury occurs as a result of pronation-abduction or pronation-external rotation loading scenarios in which avulsion of the medial malleolus or rupture of the deltoid ligament can result if the force is sufficient [1]. If left untreated, the joint may experience more severe conditions like osteoarthritis [2]. To avoid such consequences, medial ankle injuries — specifically bony injuries — are treated with open reduction and internal fixation via the use of plates, screws, wires, or some combination thereof [1, 3–4]. In this investigation, the mechanical performance of two such devices was compared by creating a 3-dimensional model of an earlier cadaveric study [5], validating the model against the cadaveric data via finite element analysis (FEA), and comparing regions of high stress to regions of experimental failure.

Rotational Stiffness of Football Shoes Influences Talus Motion during External Rotation of the Foot

2012 ◽  
Vol 134 (4) ◽  
Author(s):  
Feng Wei ◽  
Eric G. Meyer ◽  
Jerrod E. Braman ◽  
John W. Powell ◽  
Roger C. Haut
Keyword(s):  
Ankle Joint ◽  
Joint Torque ◽  
Ankle Injuries ◽  
Design Parameters ◽  
Deltoid Ligament ◽  
Rotational Stiffness ◽  
Shoe Design ◽  
Tibiofibular Ligament ◽  
Ankle Ligament ◽  
Ligament Strain

Shoe-surface interface characteristics have been implicated in the high incidence of ankle injuries suffered by athletes. Yet, the differences in rotational stiffness among shoes may also influence injury risk. It was hypothesized that shoes with different rotational stiffness will generate different patterns of ankle ligament strain. Four football shoe designs were tested and compared in terms of rotational stiffness. Twelve (six pairs) male cadaveric lower extremity limbs were externally rotated 30 deg using two selected football shoe designs, i.e., a flexible shoe and a rigid shoe. Motion capture was performed to track the movement of the talus with a reflective marker array screwed into the bone. A computational ankle model was utilized to input talus motions for the estimation of ankle ligament strains. At 30 deg of rotation, the rigid shoe generated higher ankle joint torque at 46.2 ± 9.3 Nm than the flexible shoe at 35.4 ± 5.7 Nm. While talus rotation was greater in the rigid shoe (15.9 ± 1.6 deg versus 12.1 ± 1.0 deg), the flexible shoe generated more talus eversion (5.6 ± 1.5 deg versus 1.2± 0.8 deg). While these talus motions resulted in the same level of anterior deltoid ligament strain (approxiamtely 5%) between shoes, there was a significant increase of anterior tibiofibular ligament strain (4.5± 0.4% versus 2.3 ± 0.3%) for the flexible versus more rigid shoe design. The flexible shoe may provide less restraint to the subtalar and transverse tarsal joints, resulting in more eversion but less axial rotation of the talus during foot/shoe rotation. The increase of strain in the anterior tibiofibular ligament may have been largely due to the increased level of talus eversion documented for the flexible shoe. There may be a direct correlation of ankle joint torque with axial talus rotation, and an inverse relationship between torque and talus eversion. The study may provide some insight into relationships between shoe design and ankle ligament strain patterns. In future studies, these data may be useful in characterizing shoe design parameters and balancing potential ankle injury risks with player performance.

scholarly journals Restoration of Tibiofibular Kinematics with a Tricortical Screw or Suture Button Fixation After Syndesmotic Ankle Injuries

2017 ◽  
Vol 2 (3) ◽  
pp. 2473011417S0000
Author(s):  
Conor Murphy ◽  
Thomas Pfeiffer ◽  
Jason Zlotnicki ◽  
Volker Musahl ◽  
Richard Debski ◽  
...  
Keyword(s):  
Screw Fixation ◽  
External Rotation ◽  
Tracking System ◽  
Optical Tracking ◽  
Ankle Injuries ◽  
Suture Button ◽  
Tibiofibular Ligament ◽  
Cortical Screw ◽  
Significant Difference ◽  
Posterior Translation

Category: Ankle, Sports, Trauma Introduction/Purpose: Anterior inferior tibiofibular ligament (AITFL), Posterior inferior tibiofibular ligament (PITFL) and Interosseous membrane (IOM) disruption is a predictive measure of residual symptoms after ankle injury. In unstable injuries, the syndesmosis is treated operatively with cortical screw fixation or a suture button apparatus. Biomechanical analyses of suture button versus cortical screw fixation methods show contradicting results regarding suture button integrity and maintenance of fixation. The objective of this study is to quantify tibiofibular joint motion in syndesmotic screw and suture button fixation models compared to the intact ankle. Methods: Five fresh-frozen human cadaveric specimens (mean age 58 yrs.; range 38-73 yrs.) were tested using a 6-degree-of- freedom robotic testing system. The tibia and calcaneus were rigidly fixed to the robotic manipulator and the subtalar joint was fused. The full fibular length was maintained and fibular motion was unconstrained. Fibular motion with respect to the tibia was tracked by a 3D optical tracking system. A 5 Nm external rotation moment and 5 Nm inversion moment were applied to the ankle at 0°, 15°, and 30° plantarflexion and 10° dorsiflexion. Outcome variables included fibular medial-lateral (ML) translation, anterior-posterior (AP) translation, and external rotation (ER) in the following states: 1) intact ankle, 2) AITFL transected, 3) PITFL and IOM transected, 4) 3.5 mm cannulated tricortical screw fixation, 5) suture button fixation. An ANOVA with a post-hoc Tukey analysis was performed for statistical analysis (*p<0.05). Results: Significant differences in fibular motion were only during the inversion moment. Fibular posterior translation was significantly higher with complete syndesmosis injury compared to the intact ankle at 0°, 15°, and 30° plantarflexion and the tricortical screw at 15° and 30°. Significantly higher fibular posterior translation was observed with the suture button compared to the intact ankle at 15° and 30 plantarflexion and to the tricortical screw at 15°. ER was significantly increased with complete injury compared to the tricortical screw at 0° and 30° plantarflexion. The suture button demonstrated significantly greater ER at 0° plantarflexion and 10° dorsiflexion compared to the intact ankle. The only significant difference in ML translation exists between the tricortical screw and complete injury at 30° plantarflexion. Conclusion: The suture button did not restore physiologic motion of the syndesmosis. It only restored fibular ML translation. Significant differences in AP translation and ER persisted compared to the intact ankle. The tricortical screw restored fibular motion in all planes. No significant differences were observed compared to the intact ankle. These findings are consistent with previous studies. This study utilized a novel setup to measure unconstrained motion in a full length, intact fibula. Physicians should evaluate AP translation and ER as critical fibular motions when reconstructing the syndesmosis with suture button fixation.

scholarly journals Syndesmotic Behavior after Sequential Sectioning: Simulation of Ligamentous Ankle Injuries in Vitro

2019 ◽  
Vol 4 (4) ◽  
pp. 2473011419S0001
Author(s):  
Robin P. Blom ◽  
Kaj S. Emanuel ◽  
Markus Knupp ◽  
Inger N. Sierevelt ◽  
Gino M.M.J. Kerkhoffs ◽  
...  
Keyword(s):  
External Rotation ◽  
Lower Limbs ◽  
Ankle Injuries ◽  
Deltoid Ligament ◽  
Active Motion ◽  
Need For Treatment ◽  
Ligament Rupture ◽  
Fresh Frozen ◽  
Rotation Stress

Category: Ankle, Trauma, Distal Tibiofibular Joint Introduction/Purpose: Ankle fractures are often associated with ligamentous injuries of the distal tibiofibular syndesmosis and the deltoid ligament. These injuries may predispose to instability, early joint degeneration and long-term ankle dysfunction. In the classic article of Boden it was made clear that injuries of the syndesmotic ligaments were of no importance in absence of a deltoid ligament rupture. Even in the presence of a deltoid ligament rupture, the interosseous membrane withstood lateralization of the talus in fixated fibula fractures up to 4.5 mm above the ankle joint. However, detection of ligamentous injuries and the need for treatment remain subject of ongoing debate. Syndesmotic injuries are often treated operatively by temporary fixation performed with positioning screws. But do isolated syndesmotic injuries need to be treated operatively at all? Methods: Ten fresh-frozen, exarticulated through the knee, human cadaveric lower limbs were tested under axial compressive loads of 50 and 700 N, simulating non-weightbearing and weightbearing conditions. All specimens were tested with different foot positions (plantigrade, dorsiflexion, inversion, eversion, and 10 Nm external rotational torque) during sequential sectioning of the syndesmotic ligaments and the deltoid ligament. We triangulated Boden’s classic findings with an active motion capture system (0.1 mm accuracy) to track the translations and rotations of the fibula relative to the tibia. Results: Isolated sectioning of the AITFL resulted in an increase of external fibula rotation up to 8.9 degrees (doubling the physiological 4.0 degrees) with an external rotation stress of 10 Nm in non-weightbearing conditions. However, weightbearing appeared somewhat protective, reducing the external rotation to 7.9 degrees. Sectioning of all syndesmotic ligaments with an intact deltoid ligament resulted in a syndesmotic widening of 0.9 mm in weightbearing conditions with a plantigrade foot. Dorsiflexion of the foot resulted in a significant increase of syndesmotic widening for all conditions of the syndesmotic ligaments. Sectioning of the deltoid ligament resulted in a significant increase of all fibula translations in all foot positions during weightbearing conditions. Conclusion: The results of our study have implications for common ligamentous ankle injuries and their treatment. In isolated syndesmotic injuries with a plantigrade foot, weightbearing seemed protective and limiting syndesmotic widening probably due to the saddle shape of the tibiotalar surface. Conservative treatment in a cast seems justifiable. External rotation stress causes the “open-book-phenomenon” in isolated AITFL injuries, especially in non-weightbearing conditions. Protection with cast or surgery is necessary. The deltoid ligament prevents lateralization of the talus but allows increased syndesmotic widening and external rotation of the fibula in dorsiflexion and external rotation stress due to the shape of the talus.

Determination of In Situ Ankle Ligament Strains in Cases of High and Medial Ankle Sprains

2012 ◽  
Author(s):  
Keith D. Button ◽  
Feng Wei ◽  
Eric G. Meyer ◽  
Kathleen Fitzsimons ◽  
Roger C. Haut
Keyword(s):  
Ankle Sprain ◽  
Ankle Injury ◽  
Ankle Injuries ◽  
Deltoid Ligament ◽  
Generic Model ◽  
Ankle Sprains ◽  
Ligament Injuries ◽  
Lateral Ankle Sprain ◽  
Lateral Ankle ◽  
Tibiofibular Ligament

Ankle sprain is a common occurrence in sports, accounting for 10–30% of injuries [1]. While approximately 85% of ankle sprains are lateral ankle injuries, syndesmotic (high) and medial injuries typically result in more time off the field. In order to help limit or mitigate ankle injuries, it is important to understand the mechanisms of injury. While numerous biomechanical studies have been conducted to investigate ankle injuries, most of them are designed to study ankle fractures rather than sprains. Ankle sprains have been graded in the clinical literature and associated with the degree of damage to a ligament resulting from excessive strains [2]. Recently, there have been studies of lateral ankle sprain in laboratory settings [3,4] and based on investigation of game films [5], providing considerable insight into the mechanism of lateral ankle sprain. On the other hand, few biomechanical studies have been conducted on high and medial ankle sprains. A more recent study from our laboratory used human cadaver limbs to investigate such injuries [6]. The study showed that the type of ankle injury, whether medial or high, under excessive levels of external foot rotation depends on the extent of foot eversion [6]. Everted limbs showed isolated anterior tibiofibular ligament injuries (high ankle sprain) only, while neutral limbs mostly demonstrated deltoid ligament failures (medial ankle sprain). Additionally, the study documented grade II (partial tears) and grade III (ruptures) ligament injuries. While a computational ankle model has also been developed and validated to help understand the mechanisms of injury [7], it is a generic model. The objective of the current study was to develop computational, subject-specific models from those cadaver limbs and determine the levels of ligament strain generated in the medial and high ankle injury cases, as well as correlate the grades of injury with ligament strains from the computational model.

3D Talar Kinematics During External Rotation Stress Testing in Hindfoot Varus and Valgus Using a Model of Syndesmotic and Deep Deltoid Instability

2019 ◽  
Vol 40 (7) ◽  
pp. 826-835 ◽  
Author(s):  
Jessica E. Goetz ◽  
Tanawat Vaseenon ◽  
Yuki Tochigi ◽  
Annunziato Amendola ◽  
John E. Femino
Keyword(s):  
Ankle Instability ◽  
External Rotation ◽  
Ankle Injuries ◽  
Deltoid Ligament ◽  
Starting Position ◽  
Coronal Rotation ◽  
Ligamentous Instability ◽  
Ligament Disruption ◽  
Rotation Stress ◽  
Fixed Center

Background: External rotation stress (ERS) identifies ankle instability after fibular reduction of rotational ankle injuries. Combined hindfoot and ankle motions and an inconsistent starting position could mask differing degrees of instability resulting from syndesmotic and/or deltoid ligament disruption. The goal of this work was to use full 3D talar kinematics to evaluate the effects of hindfoot orientation and foot starting position during ERS on the ability to detect instability caused by ligament disruptions. Methods: Six cadaveric ankles with metallic fiducial markers were CT scanned in neutral and 3 stress positions: varus hindfoot internal rotation stress (IRS-var), valgus hindfoot ERS (ERS-val), and varus hindfoot ERS (ERS-var). Scans were obtained in stress positions after transecting the deep deltoid ligament (tDDL) and then the syndesmotic ligaments (tDDL+Syn). Talar rotations and translations were computed in the axial, coronal, and sagittal planes in each stress position. Changes in a fixed center of rotation (CoR) relative to the intact sequence were calculated. Results: Axial plane rotation beginning from IRS-var increased significantly for each level of ligamentous instability ( P < .05 for all conditions) (10.9 degrees, intact; 14.1 degrees, tDDL; 22.7 degrees, tDDL+Syn during ERS-val; and 16.4 degrees, intact; 23.1 degrees, tDDL; 29.9 degrees, tDDL+Syn during ERS-var). With ERS-val, the talar CoR moved medially (3.6-5.4 mm) and posteriorly (0.5-5.2 mm); ERS-var moved anterior/laterally or posterior/medially depending on the specific ligamentous instability. With tDDL+Syn the ankle became grossly unstable and there were no clear trends in sagittal/coronal rotation or translation. Conclusion: An ERS test from internal to external rotation consistently differentiates between normal, tDDL, and tDDL+Syn. Talar CoR moved outside the mortise with ligamentous instability. Clinical Relevance: Significant residual deep deltoid instability is likely underrecognized with current practice. The most discriminatory test for detecting such instability in our laboratory was an ERS test performed by internally rotating the foot to a hard, bony endpoint, positioning the hindfoot in varus, and then performing the entire external rotation maneuver while maintaining the varus hindfoot position.

Deltoid ligament injury patterns in external rotation ankle injuries: A cadaveric study

2017 ◽  
Vol 23 ◽  
pp. 26-27
Author(s):  
M. Cooper ◽  
A. Mait ◽  
B. Nie ◽  
J.P. Donlon ◽  
A. Mane ◽  
...  
Keyword(s):  
External Rotation ◽  
Cadaveric Study ◽  
Ankle Injuries ◽  
Ligament Injury ◽  
Deltoid Ligament ◽  
Injury Patterns ◽  
Deltoid Ligament Injury
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