Redistribution Of Forces Research Articles

Comparison of embolization strategies for mixed plexiform and fistulous brain arteriovenous malformations: a computational model analysis of theoretical risks of nidus rupture

BackgroundHigh-flow fistulas related to plexiform nidi are found in 40% of large brain arteriovenous malformations (AVMs). Endovascular occlusion of intranidal fistulas before plexiform components is empirically considered safe, but potential...

ANALYSIS OF THE STRAIN-STRESS STATE OF THE BENDING CONTINUOUS RC-BEAMS WITH HYBRID REINFORCEMENT IN THE TENSILE ZONE UNDER INTERMEDIATE SUPPORT

The article considers the proposed model describing the stress-strain state of bent statically indeterminate reinforced concrete beams with combined reinforcement (the joint arrangement of metal and composite rods) of the stretched zone of the central support section, based on the positions of the general deformation model of cross-sections with normal separation cracks between concrete subelements formed by two adjacent cracks and the block model of the resistance of the bent element. The prerequisites and assumptions for applying the proposed model are presented. The stress-strain state of the central reference section of the considered elements is analyzed according to the proposed model. The criterion of destruction of statically indeterminate reinforced concrete beams with hybrid reinforcement of the stretched zone of the central support section is revealed, which fully allows taking into account the redistribution of internal forces between the support and span sections of the element.

Sensitivity analysis of Kiewitt-Lamella reticulated domes due to member loss

In this paper, the sensitivity analysis of Kiewitt-Lamella (K-L) reticulated domes with different parameters is carried out. The sensitivity of the dome due to gradual and sudden member loss is analyzed in both static and dynamic aspects, which will clarify the distribution rule of the member sensitivity and provide a reference for future study on the K-L reticulated dome. The results show that the member sensitivity of the K-L reticulated dome with different design parameters has similar regularities. For the members in the same ring, the sensitivity of the latitudinal members is larger than that of the diagonal members. For the members in different rings, the sensitivity of the inner ring members is larger than that of the outer ring members. In addition, the static analysis shows that the latitudinal members closer to the radial members are more sensitive than those apart from the radial members, and the diagonal members paralleling to the radial members are more sensitive than the unparallel ones. The dynamic analysis shows that the K-L reticulated dome will experience a local internal force redistribution after a member's sudden loss and finally reach a stable equilibrium state on the new load transfer path without overall progressive collapse. According to the research results, a better scheme for strengthening the structure is proposed: increasing the cross-section of sensitive members is more effective in improving the structural stability than important components.

Cracking feature and mechanical behavior of shield tunnel lining simulated by a phase-field modeling method based on spectral decomposition

Disturbed by the surrounding engineering construction, the shield tunnel lining may appear mixed-mode cracks such as segment cracking and joint crushing, which seriously damage its mechanical behaviors. To simulate the shield tunnel lining with mixed-mode cracks, a phase-field modeling method based on spectral decomposition is proposed, which unifies the critical energy release rate and crack-driving strain energy. The indoor full-scale tests are carried out to study the failure mechanism of the segment and joint. The phase-field modeling method is verified by the tests, and the influence of loading path on the cracking feature and mechanical behavior of the segment and joint are analyzed by the proposed numerical method. The test and numerical simulation indicate that the crack in the segment gradually develops from I-type crack (tensile crack) to Y-type crack (tensile-shear crack), and the joint is crushed due to local compression, and the crushed region expands gradually with the increase of the eccentricity. As the eccentricity decreases, the ultimate bearing capacity of the segment and joint is improved, while the ductility decreases. Then, the phase-field modeling method is extended to the stratum-structure model. As the surface load increases, the joints of the shield tunnel lining are crushed, and the top and bottom segments are cracked. Meanwhile, the bending moment is reduced due to the redistribution of internal forces caused by the segment cracking and joint crushing.

Analysis on the mechanical properties of the crossbeam of a new ground anchor counterfort grille dam considering bearings displacement

Aiming at the problem that the uneven deformation of the crossbeam of the new ground anchor counterfort grille dam under the impact of debris flow is easy to cause the overall damage of the structure, the crossbeam is simplified as a mechanics model of multi − span continuous beam supported on the grille columns, and the internal force calculation formulas of the crossbeam under the displacement and the local failure of the bearings are deduced. Combined with an example, during the process of bearings from the displacement to local failure, the internal force variation of the crossbeam are analyzed. The results show that when the single bearing is displaced, the mid − span bearing has the greatest impact on the internal force of the crossbeam. When the two bearings are displaced at the same time, the two side − span bearings have a greater influence on the internal force of the crossbeam. When three bearings are displaced at the same time, the influence on the internal force of the crossbeam is the smallest. When the single bearing fails, the failure of side − span bearing has the greatest influence on the internal force of the crossbeam, the mid − span bearing failure is second. Therefore, the reinforcement at each bearing of the crossbeam should be considered to meet the force requirements after the internal force redistribution in the design, so as to ensure the safety of the structure after the positive and negative bending moment of bearing are converted. In addition, when displacement or failure of bearings occur, attention should be paid to meet the limit requirements of structural deformation and stability. The research results can provide a theoretical basis for the reliability analysis of the new ground anchor counterfort grille dam.

Flexural Behaviour and Internal Forces Redistribution in LWAC Double-Span Beams.

This research study aimed to investigate the effect of the lightweight aggregate concrete and steel reinforcement interaction on the behaviour of continuous beams compared to the normal concrete of the same strength. This paper presents six full-scale, double-span beams with a rectangular cross-section made of both lightweight and normal concrete. The study confirmed that beams made of lightweight aggregate concrete achieve comparable flexural capacities to those made of NWC but their deformability and ductility are lower. Although the redistribution of internal forces depends mainly on the longitudinal reinforcement ratio, the influence of ultimate compressive strains of concrete is also noticeable. The ultimate compressive strains in LWAC are generally lower than in NWC. The lower rotational capacity of LWAC results in smaller degrees of moment redistribution in beams made of this concrete compared to normal concrete beams.

Analysis of Fire Resistance of Square-Cased Square Steel Tube Reinforced Concrete (ST-RC) Columns.

Based on the finite element (FE) analysis software Abaqus, an FE model of square-cased square steel tube reinforced concrete (ST-RC) columns under the hybridized action of high-temperature and load is established. The accuracy of the FE model is verified using experimental data from existing studies. This model is used to analyze the temperature change, internal force distribution, and failure characteristics of the square-cased square ST-RC columns under the action of fire, as well as the factors affecting the fire resistance limit of the column. The results of FE analysis show that under the action of fire, the maximum internal temperature of the square-cased square ST-RC columns occurs in the corner of the section. Moreover, the stress and strain reach their maximum values at the concrete corner outside the tube. During the heating process, an internal force redistribution occurs in the square-cased square ST-RC column. At the same time, the proportion of the axial force and the bending moment of the reinforced concrete outside the pipe decreases gradually, while the proportion of the internal force of the core concrete-filled steel tube (CFST) increases gradually. In essence, it is a process of load transfer from the high-temperature to the low-temperature zone. In addition, the section size, load ratio, slenderness ratio, cross-sectional core area ratio, steel content, and external concrete strength are the main parameters affecting the fire resistance limit of the square-cased square ST-RC columns. Among them, the cross-sectional core area ratio, section size, steel ratio, and external concrete strength are positively correlated with the fire resistance limit of the composite column. On the contrary, with the increase in the load ratio and the slenderness ratio, the fire resistance limit of the square-cased square ST-RC columns decreases. On this basis, a simplified formula to calculate the fire resistance limit of square-cased square ST-RC columns is proposed. The research results can be used as a theoretical reference for the fire protection design of this kind of structure in practical engineering.

Dynamics of a viscoelastic thread surrounded by a Newtonian viscous fluid inside a cylindrical tube

A viscoelastic thread in vacuum is known to evolve into a beads-on-a-string structure at large deformations. If the thread is immersed in another fluid, the surrounding medium may influence the topological structure of it, which remains unexplored. To get some insights into the nonlinear behaviour of a viscoelastic thread in a two-phase flow system, a one-dimensional model is developed under the slender body approximation, in which the thread of a highly viscoelastic fluid described by the Oldroyd-B or Giesekus constitutive equation is immersed in a Newtonian viscous fluid of much smaller density and viscosity inside a cylindrical tube. The effect of the outer viscous fluid layer and the confinement of the tube is examined. It is found that the outer fluid may change substantially the beads-on-a-string structure of the viscoelastic thread. Particularly, it may induce the formation of secondary droplets on the filament between adjacent primary droplets, even for large wavenumbers. The outer fluid exerts a resistance force on the extensional flow in the filament, but the necking of the thread is slightly accelerated, due to the redistribution of capillary and elastic forces along the filament accompanied by the formation of secondary droplets. Decreasing the tube radius leads to an increase in secondary droplet size but affects little the morphology of the thread. The non-uniformity of the filament between droplets is more pronounced for a Giesekus viscoelastic thread, and pinch-off of a Giesekus thread always occurs in the neck region connecting the filament to the primary droplet in the presence of the outer viscous fluid.

Crack propagation and residual load‐bearing behavior of composite dowels – effects on the global behavior of composite girders under cyclic loading

AbstractFatigue of a composite girder according to Eurocode 4 is carried out on the decisive shear connector. It is not taken into account that the composite girder is an internally highly statically indeterminate system in which the failure of a dowel does not necessarily lead to the failure of the girder. This applies in particular to composite dowels which are characterised by a crack propagation phase with a high residual load‐bearing capacity of a damaged dowel.In own small part and girder tests as well as numerical studies, numerous positive load‐bearing effects could be identified in composite girders with composite dowels, which increase the lifetime of the girder. In case of an initial crack in a steel dowel, followed by crack propagation, the stiffness degradation of the damaged connector leads to a redistribution of forces. The lifetime of a girder is limited by the residual capacity of the composite joint or by a global failure with increasing partial connection.A global safety concept for composite girders taking into account the crack development and residual strength of the dowels as well as the redistribution of forces within the composite joint holds an enormous economic potential. This article shows how these effects can be taken into account.

Numerical investigations on built‐up cold‐formed steel beams for long spans

AbstractThe material saving obtained by using thin‐walled cold‐formed steel elements is well‐known for small structures as well as for common industrial structures. Additional to the truss type structures, another solution for obtaining light‐weight elements consist of connecting cold‐formed steel profiles as the flange to the corrugated steel sheets as the web. The resistance spot welding connecting technique is an advanced solution which offers reduced manpower and time for element production. These built‐up elements have shown their feasibility and high bearing capacity in previous studies. The present paper highlights additional characteristic responses of cold‐formed steel elements that extend in the response of built‐up corrugated web beams. The parameters considered in the numerical model include the span of the beam, the height of the beam, the thickness of the corrugated web plates, the thickness of the shear panel, the number of resistance spot welds and the orientation of the beam axis. By considering the real case configuration of industrial buildings, pitched roofs require the beams to have an inclination. The analyzed inclined beams exhibited increased capacity due to the redistribution of internal forces, growing the attractiveness of this solution.

Hysteretic Behaviour of Shear Stud Connectors in Composite Steel Moment‐Resisting Frames

AbstractIn steel moment resisting frames (MRFs) with composite floor slabs, seismic loads are transmitted from the slab into the beam through shear studs. Shear strength degradation of the studs due to cyclic loading results into the loss of the load transfer mechanism and composite action. To date, several low‐cyclic, high‐amplitude push‐out tests have been conducted to characterize the shear stud hysteretic behaviour. These isolated tests showed considerable degradation in the shear stud resistance; nevertheless, they do not simulate the actual hysteretic behaviour of shear studs within a composite steel beam. To elaborate, conventional cyclic push‐out tests do not replicate the actual stress state in the concrete slab, nor do they account for the force redistribution between the shear studs. This paper investigates the hysteretic behaviour of shear studs in steel MRFs with composite floor slabs. The load‐slip hysteretic behaviour of the shear studs is examined through continuum finite element (CFE) models of 2‐bay sub‐systems and their corresponding cruciform subassemblies. Moreover, shear force and interlayer slip envelopes are obtained along the composite steel beams. Results of the CFE models are used to propose new design recommendations for shear studs in composite‐steel MRFs.

Experimental study on collapse behaviour of truss string structures under cable rupture

Cables are key components of truss string structures, and their sudden rupture may cause severe damage and progressive collapse of the structures. In this paper, cables were selected as the initial failure component, and the failure effect of a planar truss string structure with 6-m span was investigated through both experiments and numerical simulations. The deformation, internal force redistribution and oscillatory response of the remaining structure were obtained, and the progressive collapse failure mechanism was revealed. The results showed that, after the cable rupture, the stress state of the upper truss changed from an arch to a simply-supported beam, the lower chords of the middle span first exhibited plastic strain, then the mid-span upper chords and web members buckled successively, the structure collapsed. However, owing to the friction in the test, the structure demonstrated a slower collapse rate in the test than in numerical simulation. It was found that when the elastic support stiffness of the finite element model was 775 kN/m, the simulation results were more consistent with the experimental data, which further illustrated the correctness of the numerical simulation. In addition, the duration of the progressive collapse process of structures is very short, it is necessary to research anti-collapse measures.

Experimental investigation and analysis for hydrodynamic behaviours and progressive collapse phenomenon of submerged floating tunnel under anchor cables’ breakage

ABSTRACT The hydrodynamic behaviours and progressive collapse phenomenon of the submerged floating tunnel (SFT) under anchor cable breakage are experimentally investigated in this study. A physical scale segment model of the SFT under wave and current loadings is designed and studied in wave-current flume. A specially designed anchor cable breakage device is presented. The experimental data are observed to conform well to the numerical calculation results. The dynamic performance of the SFT under anchor cable breakage is comprehensively investigated based on varying effect factors. The results from the test indicate that the response variation assessment, transient effect, force redistribution and impact force in different cases are the key factors to determine the probability of instability and progressive collapse of the SFT under cable breakage. The results can provide valuable design and construction recommendations to avoid potential engineering risks and ensure the safety and stability for the SFT under marine environment.

Numerical simulation and mechanical model of steel beam-to-column joints retrofitted by haunches

Within the retrofitting of steel structures, welding haunches to retrofit weak panel zones in beam-to-column joints are deemed to provide reliable cyclic behavior based on previous tests. Also, the force transferring mechanism in haunched beam sections is substantially changed under the influences of the haunch and panel zone. For the investigation of the behavior of the haunched beam section and the haunch, finite element models (FEMs) were established with considerations of material and geometry nonlinearities and then verified against previous tests. The force distributions were obtained and also predicted by mechanical models. Results showed that the moment resistance and initial rotational stiffness increased by 34.3%–76.9% and 51.6%–83.3% through retrofitting. Moreover, a noticeable difference in force distributions was observed in the haunched beam section. The direction of the shear force within the shear plate was reversed and its value could be even greater than the beam load. After the yielding of panel zones, the force redistribution appeared and subsequently led to increased forces in the shear plate and haunch flange. Furthermore, the comparisons among mechanical models indicated that the AISC model might underestimate the contributions of both the haunch flange and the shear plate in the elastic stage, and the plane-section-assumption model showed better agreements. However, without considering the force redistribution in the post-yielding stage, the above two models underestimated forces by 8.8%–32.0% and 9.7%–64.2%, respectively, and the simplified model was proposed with better predictions concerning the impact of the force redistribution to provide a greater safety margin in design.

Craniovascular traits and braincase morphology in craniosynostotic human skulls.

Middle meningeal vessels, dural venous sinuses, and emissary veins leave imprints and canals in the endocranium, and thus provide evidence of vascular patterns in osteological samples. This paper investigates whether craniovascular morphology undergoes changes in craniosynostotic human skulls, and if specific alterations may reflect structural and functional relationships in the cranium. The analyzed osteological sample consists of adult individuals with craniosynostoses generally associated with dolichocephalic or brachycephalic proportions, and a control sample of anatomically normal adult skulls. The pattern and dominance of the middle meningeal artery, the morphology of the confluence of the sinuses, and the size and number of the emissary foramina were evaluated. Craniovascular morphology was more diverse in craniosynostotic skulls than in anatomically normal skulls. The craniosynostotic skulls often displayed enlarged occipito-marginal sinuses and more numerous emissary foramina. The craniosynostotic skulls associated with more brachycephalic morphology often presented enlarged emissary foramina, while the craniosynostotic skulls associated with dolichocephalic effects frequently displayed more developed posterior branches of the middle meningeal artery. The course and morphology of the middle meningeal vessels, dural venous sinuses, and emissary veins in craniosynostotic skulls can be related to the redistribution of growth forces, higher intracranial pressure, venous hypertension, or thermal constraints. These functional and structural changes are of interest in both anthropology and medicine, involving epigenetic traits that concern the functional and ontogenetic balance between soft and hard tissues.

Numerical study on collapse-resistant performance of multi-story composite frames under a column removal scenario

In practice, when building structures are subjected to local damage caused by extreme loads, all stories above the failure column consequently deform and play a major role in the internal force redistribution and rebalancing for resisting the external load. However, because of the high cost and laboratory space constraints, most existing experimental tests on progressive collapse are primarily focused on single-story sub-assemblages. In a previous experimental work, to investigate the collapse performance of a multi-story composite frame, a 1/3 scale three-story composite sub-frame with top and seat with double web angle (TSDWA) connections was tested quasi-statically. However, whereas many factors have a significant influence on the progressive collapse performance, the corresponding experimental data proved too limited to allow their analysis. Consequently, to address these limitations and explore the effects of key parameters on the progressive collapse behavior of multi-story composite frames, a series of progressive collapse simulations were conducted in this study and the corresponding critical parameters identified. First, a finite element model of the three-story composite sub-frame was established and validated with the prior experimental results. Then, the effects of composite slabs and lateral restraints on the collapse performance were investigated using a refined model. Subsequently, the effect of model size was determined and parametric analyses were carried out to investigate the effects of key parameters on the progressive collapse performance, including number of stories, span-to-depth ratio, and column-removal position. Finally, the TSDWA connections were reinforced by adding stiffeners on both sides of the top and seat angles, which effectively improved the collapse resistance of the multi-story composite frame under different collapse conditions.

Digital occlusal analysis of pre and post single posterior implant restoration delivery: A pilot study.

ObjectivesThe purposes of this study were to analyze the effects of single posterior implant restorations delivery on the redistribution of bite force and to evaluate the changes in occlusal force distribution of prostheses and potential influencing factors on occlusion variation at different stages.Materials and methodsThirty-two single posterior restorations in 30 participants (18 women and 12 men aged 27 to 75 years) were placed into either a unilateral single-tooth defect (n = 17) or on either side of a bilateral teeth defects (n = 15). The bite force (%) of the prostheses, teeth and segments at the maximum intercuspation position (MIP) was evaluated using a T-scan at 5 stages (pre-placement, immediately following placement, and 2 weeks, 3 months, and 6 months post-placement).ResultsThe occlusal force of implant-supported prostheses was significantly (P = .000) lower than those of the control natural teeth at the baseline, then no significant difference was found with that of the mesial teeth at 3 months, and finally it was significantly (P = .000) lower than that of the distal teeth at 6 months; meanwhile, it significantly (P = .008) increased by a mean of 2.04 times from 2 weeks (3.39 ± 2.61%) to 3 months (6.90 ± 4.77%), whereas no significant difference (P = .900) was found from 3 months (6.90 ± 4.77%) to 6 months (7.31 ± 4.60%). In addition, the bite force of the posterior segment on the restored side of both unilateral and bilateral gaps was significantly (P = .013,.001) improved by 3.31% and 6.83%, respectively, although the discrepancy in bite force significantly (P = .039) increased from an initial 3.52% to 5.02% for subjects with bilateral defects, accompanying increases in the proportion (15.38%) of the level III bilateral bite force deviation (P >.05).ConclusionsBite force and masticatory ability can be improved with the immediate delivery of a single posterior implant restoration. The bite force distributed on the implant prosthesis inevitably increases after placement of implant prostheses, a routine follow-up and occlusal evaluation are strongly needed.

Influence of foundation dimensions of grain drying complexes on the nature of the redistribution of efforts in the foundation structures

The work of the pile foundation of the grain drying complex at change of dimensions of the base plate, namely change of its thickness is investigated. Calculations were performed using numerical simulation by the finite element method of three variants: 1) at a base plate thickness of 400 mm; 2) at a thickness of a base plate of 500 mm; 3) at a thickness of a base plate of 600 mm.
 After the calculations, the stress-strain state (SSS) of the foundation structures of the grain-drying complex was analyzed: redistribution of forces in the piles, deformation of the foundation structures, redistribution of bending moments in the foundation slab and selected the appropriate area of working reinforcement of the foundation slab.
 In the work, pile foundations were used as the foundations of grain drying complexes due to the presence of weak soils and loess subsidence soils from the surface of the construction site.
 For the design of pile foundations, the load from the weight of the grain from the own weight of the silo structure and from the weight of the foundation slab was taken into account. Moreover, the load from the grain was taken into account as a variable over time due to the loading and unloading of silage.
 The study was conducted in clay soils of refractory, semi-hard and hard consistency. At the base of the pile foundation are loams of semi-solid consistency.
 As a result of this work, it is shown that the in-crease in the thickness of the foundation slab has almost no effect on the change in the settlement of the foundation slab. As the thickness of the foundation slab increases (the stiffness increases accordingly), the bending moments in it increase, which leads to an increase in the reinforcement of the foundation slab, in some areas up to 20%, and the reinforcement area up to 4 times. The force in the piles varies as follows: in the outer row of piles the force increases to 15%, and in the middle row of the force decreases to 10%. Comprehensive analysis of research results allows to design reliable and economical solutions of pile foundations of grain drying complexes.

The role of parameters of foundation structures in the formation of a stress-strain state of the foundations of the building

Requirements for the reliability and cost-effectiveness of rational foundation structures determine the performance of calculations taking into account the interaction of the loadbearing structures of the building with the soil base. Computer modeling makes it possible to perform such calculations and obtain the stress-strain state of the structures of the building and the soil base.
 Numerical modeling of the interaction of a building with a soil massif makes it possible to study the influence of all components of the system "soil base - foundation - building". At the same time, during numerical modeling it is possible to consider different options for the location of elements in the plan, different geometric dimensions of the elements and their properties. The results of the interaction calculations of the building with the soil base make it possible to choose the best option for foundation structures, which is cost-effective and ensures reliable operation of the building.
 In this study, the search for rational parameters of the foundation structures of the building was performed by numerical modeling of the joint work of the elements of the system "soil base - foundation - building". The study was performed on the example of a 16-storey frame building.
 A study of the influence of the parameters of the pile foundation on the stress-strain state of the foundation structures and bearing elements of the frame of the building:
 -The influence of the piles location in the plan is considered. The process of redistribution of forces in piles depending on the amount and location within the contour of the building is investigated. Deformation assessment is performed.
 -The optimal pile length has been searched. The relationship between the length of piles and deformations, their load-bearing capacity and quantity has been studied. The distribution of piles according to the coefficient of use of their bearing capacity has been obtained.
 -A study of the influence of the stiffness of the foundation pile cap on the redistribution of stresses and strains in the structures of the building. The relationship between the thickness of the pile cap and the percentage of reinforcement elements of the frame of the building has been obtained.
 It is confirmed by the results of the research that the use of numerical modeling of the interaction of the pile foundation with the soil base allows to obtain a quantitative assessment of the stress-strain state. It becomes possible to search for rational parameters at the design stage of foundation structures.

Osteotomies around the knee lead to corresponding frontal realignment of the ankle

IntroductionDespite the fact that osteotomies around the knee represent well-established treatment options for the redistribution of loads and forces within and around the knee joint, unforeseen effects of these osteotomies on the ankle are still to be better understood. It was therefore the aim of this study to determine the influence of osteotomies around the knee on the coronal alignment of the ankle. We hypothesize that osteotomies around the knee for correction of genu varum or valgum lead to a change of the ankle orientation in the frontal plane by valgisation or varisation.Materials and methodsLong-leg standing radiographs of 154 consecutive patients undergoing valgisation or varisation osteotomy around the knee in 2017 were obtained and utilized for the purpose of this study. Postoperative radiographs were obtained after union at the osteotomy site. The hip knee ankle angle (HKA), the mechanical lateral distal femur angle (mLDFA), the mechanical medial proximal tibia angle (mMPTA) and five angles around the ankle were measured. Comparison between means was performed using the Wilcoxon-Mann–Whitney test.ResultsOne hundred fifty-four patients (96 males, 58 females) underwent osteotomies around the knee for coronal realignment. The mean age was 51 ± 11 years. Correction osteotomies consisted of 73 HTO, 54 DFOs, and 27 double level osteotomies. Of all osteotomies, 118 were for valgisation and 36 for varisation. For valgisation osteotomies, the mean HKA changed from 5.8° ± 2.9° preoperatively to − 0.9° ± 2.5° postoperatively, whereas the mMPTA changed from 85.9° ± 2.7° to 90.7° ± 3.1° and the malleolar-horizontal-orientation-angle (MHA) changed from 16.4° ± 4.2° to 10.9° ± 4.2°. For varisation osteotomies, the mean HKA changed from − 4.3° ± 3.7° to 1.1° ± 2.2° postoperatively, whereas the mLDFA changed from 85.7° ± 2.2° to 89.3° ± 2.3° and the MHA changed from 8.8° ± 5.1° to 11.2° ± 3.2°.ConclusionOsteotomies around the knee for correction of coronal limb alignment not only lead to lateralization or medialization of the weight-bearing line at the knee but also lead to a coronal reorientation of the ankle. This can be measured at the ankle using the MHA. When planning an osteotomy around the knee for correction of genu varum or valgum, the ankle should also be appreciated—especially in patients with preexisting deformities, ligament instabilities, or joint degeneration around the ankle.