Rotational Deformity Research Articles

Treatment of 5th Metecarpal Neck Fractures with Titanium Elastic Nail Using Local Anesthesia and Hematoma Block

Objective:Surgical treatment of 5th metacarp neck fractures using titanium elastic nail (TEN) is performed under general anesthesia or axillary block. In this study, our aim is to present the clinical and radiological results of patients who underwent surgery under local anesthesia for the TEN entry site and hematoma block for fracture reduction. Methods: There were 14 patients who met the inclusion criteria in the study. Radiologically, metacarpal shortness and volar angulation angles at the time of admission, after reduction in the ER and after surgical intervention when the fusion had been achieved were evaluated. Clinically, rotational deformity, range of motion of the affected finger were evaluated according to Quick DASH scores. Results: The volar angulation before and after reduction in ER was found to be as a mean of 46.2° (33-60°) and 40.6° (30-48°) respectively. After surgical intervention a mean of 17.2° (10-22°) was achived at the final follow-up. The metecarpal shortness was determined to be mean 4.4 mm (1.8-7.3mm) on first presentation, 3 mm (2-5 mm) after reduction in ER, and 2 mm (1.2-3.3mm) at the final follow-up examination in surgically treated group compared to healthy side. Radiological bone union was observed in mean 35 days, there was no pain on palpation, and the TEN was removed. Finger flexion and extension were determined to be full at the end of the 3rd month and no rotational defomity was observed. The mean Quick DASH score of the patients was 1.5 (1.2-2). Conclusion:5. metacarpal fractures with TEN under hematoma blockage and local anesthesia and leaving the proximal end out of the skin is a safe method for the treatment of such fractures.

Pediatric Forearm Fractures: Investigating the Functional Outcomes of Titanium Elastic Nailing for Unstable Both-Bone Fractures.

Diaphyseal forearm fractures pose a common challenge in children and adolescents, impacting forearm function due to rotational deformities and angulation. The landscape of pediatric forearm fracture treatment has seen limited progression, with increased surgical intervention adoption driven by factors such as functional implications, technological advancements, societal expectations, and legal concerns. This study enrolled consecutive children aged 5-16 years with forearm fractures presenting between August 2018 and January 2020, requiring surgical intervention. The study assessed functional outcomes and complications in children treated with titanium elastic nailing. Sixteen patients underwent surgery for both-bone forearm fractures. Elastic nailing was the primary intervention, with 75% undergoing closed nailing. Patients' ages ranged from 5 to 15 years, with 87.5% being male. The study evaluated fracture characteristics, surgical procedures, post-operative care, and complications. The study demonstrates promising outcomes for flexible intramedullary nailing in pediatric forearm fractures. Despite the observed complications, the majority of cases achieved excellent results in fracture union and patient recovery, supporting the efficacy of this technique. Larger cohorts are needed for a comprehensive understanding of its applicability and outcomes in pediatric forearm fracture management.

Research on Surrounding Rock Deformation and Mining Field Stress Distribution during Gob‐Side Entry Retaining by Roof Cutting and Pressure Releasing in the Inclined Thick Coal Seam

In recent years, the technology of the gob‐side entry retaining by roof cutting and pressure releasing (GERRC) has been widely used in coal mining. However, the stability of the roadway surrounding rock structure during GERRC in the coal seam with high dip angles is a major concern, limiting the widespread application of this technology. In this study, we analyzed the deformation and stress evolution of roadway surrounding rock during GERRC in the 011810‐working face of Jinfeng Coal Mine using theoretical analysis and numerical simulation. The results show that in coal seams with high dip angles, the gangue in the gob will slide down the lower trough, providing enough support for the upper rock layer and limiting rotation deformation along the gob‐side entry roof during GERRC. This weakens the impact of mining pressure on the roadway and promotes the stability of the surrounding rock structure. However, the stress in the coal of the lower roadway in the advanced influence area is the largest, reaching 16.3 MPa due to the influence of buried depth. The stress of the surrounding rock of the gob‐side entry tends to be stable at 110 m behind the working face in the lower roadways. There is also an obvious pressure relief zone in the coal in front of the working face, 10 m away from the cutting line, during GERRC. Its maximum stress is only 61.3% of the advanced coal and 10.0 MPa, indicating that the pressure relief effect of the roof cutting on the inclined coal seam is significant.

Symmetry-Breaking-Induced Internal Mixing Enhancement of Droplet Collision

Binary droplet collision is a basic fluid phenomenon for many spray processes in nature and industry involving lots of discrete droplets. It exists an inherent mirror symmetry between two colliding droplets. For specific cases of the collision between two identical droplets, the head-on collision and the off-center collision, respectively, show the axisymmetric and rotational symmetry characteristics, which is useful for the simplification of droplet collision modeling. However, for more general cases of the collision between two droplets involving the disparities of size ratio, surface tension, viscosity, and self-spin motions, the axisymmetric and rotational symmetry droplet deformation and inner flow tend to be broken, leading to many distinct phenomena that cannot occur for the collision between two identical droplets owing to the mirror symmetry. This review focused on interpreting the asymmetric droplet deformation and the collision-induced internal mixing that was affected by those symmetry breaking factors, such as size ratio effects, Marangoni Effects, non-Newtonian effects, and droplet self-spin motion. It helps to understand the droplet internal mixing for hypergolic propellants in the rocket engineering and microscale droplet reactors in the biological engineering, and the modeling of droplet collision in real combustion spray processes.

The Efficacy of Derotation Taping in Femoral Internal Rotation Deformity of Children with Cerebral Palsy: A Randomized Controlled Trial

Amaç: Bu çalışmanın amacı femoral internal rotasyon deformitesi olan hemiplejik serebral palsili çocuklarda konvansiyonel rehabilitasyona ek olarak Kinesio Bantlama ile derotasyon yönteminin etkisini araştırmaktı.
 Gereç ve Yöntem: Tek taraflı hemiplejik spastik serebral palsili toplam 30 çocuk Kinesio Bantlama ve kontrol grubuna (Konvansiyonel Rehabilitasyon) randomize edildi. Tüm katılımcılar spastisiteye bağlı rotasyon deformitesine ve “in-toeing” yürüyüşe sahipti. Kinesio Bantlama grubu konvansiyonel rehabilitasyona ek olarak derotasyon bandı ile tedavi edildi. Veriler müdahaleden önce ve hemen sonra ve ayrıca ilk değerlendirmeden 3 gün sonra toplanmıştır. Çocukları değerlendirmek için 6 Metre Yürüme Testi, Pediatrik Berg Denge Testi, Modifiye Ashworth Ölçeği, Edinburgh Görsel Yürüme Skoru ve Çocuklar için Genel Yaşam Kalitesi Ölçeği kullanılmıştır.
 Bulgular: Spastisite skorları açısından gruplar arasında anlamlı fark yoktu (p>0.05). Kinesio Bantlama grubunda müdahaleden hemen sonra ve akut dönemde kalça iç rotator kaslarında ve diz fleksörlerinde spastisite azaldı (p0.05). Müdahale sonrası 6 Metre Yürüme Testi, Pediatrik Berg Denge Testi ve Edinburgh Görsel Yürüme Skoru skorlarındaki iyileşme sadece Kinesio Bantlama grubunda anlamlıydı (p

Failure mechanism and dynamic response of reinforced concrete joints under impact load acting on beam ends

Beam-column joints are crucial to guarantee the integrity and ductility of reinforced concrete (RC) frame structures. Considering the strain rate effect, the failure mechanism of RC beam-column joints under impact load acting on the beam near the core area of joints was numerically investigated. Based on the verified numerical model, the differences between failure modes of joints under static and dynamic loads were compared. The deformation and damage of joints were analyzed. In addition, the effects of impact location and impact velocity were discussed. The results show that the joints that meet the shear demand under static load have shear failure under impact load. The impact load causes greater deformation and damage to the joints. The transfer of the shear force and the development of the bending moment is different as the impact location changes, resulting in various dynamic responses. As the impact location approaches the core area, the joint evolves from bending failure to shear failure. The maximum shear force only appears at the impact location when the distance between the impact location and the core area is more than 3.5 times the width of the core area (b). However, the rotation of the joint causes the yield of the stirrup in the core area. It is worth noting that when the distance is less than or equal to 2b, the maximum shear force is transmitted to the core area. With the decrease of the distance, the time history curves of impact force have multiple peaks with increased peak values while the displacement and duration decrease. The damage range of the joint is expanded when impacted with higher velocities. Meanwhile, the magnitude and duration of impact force, as well as displacement are increased. With the decrease of distance or impact velocity, more energy is consumed by concrete rather than rebars due to the smaller rotational deformation of the joint.

Liquid Crystal Elastomer Artificial Tendrils with Asymmetric Core-Sheath Structure Showing Evolutionary Biomimetic Locomotion.

The sophisticated and complex haptonastic movements in response to environmental-stimuli of living organisms have always fascinated scientists. However, how to fundamentally mimic the sophisticated hierarchical architectures of living organisms to provide the artificial counterparts with similar or even beyond-natural functions based on the underlying mechanism remains a major scientific challenge. Here, liquid crystal elastomer (LCE) artificial tendrils showing evolutionary biomimetic locomotion are developed following the structure-function principle that is used in nature to grow climbing plants. These elaborately designed tendril-like LCE actuators possess an asymmetric core-sheath architecture which shows a higher-to-lower transition in the degree of LC orientation from the sheath-to-core layer across the semi-ellipse cross-section. Upon heating and cooling, the LCE artificial tendril can undergo reversible tendril-like shape-morphing behaviors, such as helical coiling/winding, and perversion. The fundamental mechanism of the helical shape-morphing of the artificial tendril is revealed by using theoretical models and finite element simulations. Besides, the incorporation of metal-ligand coordination into the LCE network provides the artificial tendril with reconfigurable shape-morphing performances such as helical transitions and rotational deformations. Finally, the abilities of helical and rotational deformations are integrated into a new reprogrammed flagellum-like architecture to perform evolutionary locomotion mimicking the haptonastic movements of the natural flagellum.

Artificial Intelligence in Scoliosis: Current Applications and Future Directions

Scoliosis is a three-dimensional deformity of lateral bending and rotation of the spine. Artificial intelligence (AI) is a set of theories and techniques for studying artificial intelligence, which realizes machine intelligence by simulating and expanding human intelligence. With the continuous development of the multidisciplinary integration trend of modern medicine, artificial intelligence is used more and more in the diagnosis and treatment of scoliosis. Artificial intelligence has been widely used in the study of scoliosis and has penetrated into all fields of clinical practice of scoliosis. At present, artificial intelligence has shown good application prospects in early screening, diagnosis, treatment decision making, intraoperative operation, and prognosis prediction of scoliosis. This paper mainly summarizes the application of artificial intelligence in the clinical practice of scoliosis, and briefly introduces the AI model and its specific applications. In addition, this paper also discusses the limitations and future development of artificial intelligence. In the future, artificial intelligence will bring greater convenience to the diagnosis and treatment of scoliosis and provide better therapeutic effects for patients.

Complex Relationship of Left Ventricular Rotational Mechanics and Deformation Represented by Strain Parameters in Healthy Adults—Detailed Analysis from the Three-Dimensional Speckle-Tracking Echocardiographic MAGYAR-Healthy Study

Introduction: Left ventricular (LV) strains are measures of deformation that reflect LV function quantifying the rate of LV contraction, providing information in three directions in space: radial (RS), longitudinal (LS) and circumferential directions (CS). The LV moves around its longitudinal axis in a special movement called LV rotational mechanics. The present study aimed to assess associations between three-dimensional speckle-tracking echocardiography (3DSTE)-derived LV rotational mechanics and LV strains in healthy adult subjects. Methods: The present study consisted of 174 healthy adults (mean age: 32.8 ± 12.2 years, 79 males). Complete two-dimensional Doppler echocardiography and 3DSTE were performed in all subjects. Results: While LV-gRS and LV-gLS did not show associations with increased basal LV rotation, the lowest LV-gCS was seen in the presence of the highest LV basal rotation. An increase in basal LV rotation and consequential LV twist were not associated with apical LV rotation. While LV-gLS was not associated with the increase in apical LV rotation, LV-gRS and LV-gCS showed a trend towards increasing values. An increase in LV-gRS was associated with an increasing trend towards apical LV rotation, LV twist and LV-gCS and the preservation of basal LV rotation. LV-gLS also increased but only up to a certain value. An increase in LV-gCS was associated with a tendency towards a decrease in basal LV rotation and a tendency towards an increase in LV-gRS and LV-gLS. The highest LV-gCS was associated with the highest apical LV rotation and LV twist. The highest apical LV rotation, LV twist and LV-gCS were seen in the presence of the highest LV-gLS, while basal LV rotation and LV-gRS were not associated with increasing LV-gLS. Conclusions: Basal LV rotation has been shown to have an inverse relationship with LV-gCS, but without being related to LV-gRS and LV-gLS, while apical LV rotation is associated with LV strains in all directions, but to a different extent, suggesting a complex relationship between LV rotational mechanics and LV strains in healthy adults.

Tibial derotation osteotomies are effective inimproving pain andfunction andavoiding hip arthroscopy inpatients with hip pain-a short-term follow-up.

The primary objective was to determine short-term clinical outcomes following distal tibial derotation osteotomy (DTDO) performed to manage hip pain in the presence of tibial maltorsion and to review how co-existing pathomorphology affected the management. All patients undergoing DTDO for hip pain with tibial rotational deformities recognized as the predominant aetiology were included. Normal tibial torsion range was assumed as 0-40°, measured by trans-malleolar line relative to femoral posterior condyles. All patients had a positive hip impingement test Flexion Adduction Internal Rotation test (FADIR). The patients older than 50 years or presenting with degenerative joint changes and neuromuscular conditions were excluded. Associated ipsilateral MRI-defined intra-articular pathomorphology (cam/pincer), non-cam/pincer-related labral tears and abnormal combined femoral/acetabular version (McKibbin index) were noted. Pre-operative and post-operative functional outcomes were analysed. Thirty-two patients underwent DTDO. Mean tibial torsion was 48.8° (41-63°), average age was 27 years (18-44), and average follow-up was 30 months (16-45). Nine patients (28%) had a co-existing cam/pincer, and eight patients (25%) had an excessive McKibbin index (51-76°). Overall, 63% of all patients (including 54% of patients with co-existing pathology) experienced significant hip functional improvement following DTDO alone. Pre-operative vs 12 months post-operative scores were calculated as follows: International Hip Outcome Tool-12-41 vs 67 (P < 0.01); Hip Outcome Score Activities of Daily Living Scale-47 vs 70 (P < 0.05); and Hip Outcome Score Sport Scale-36 vs 64 (P < 0.05). Patients with hip pain frequently present with a combination of tibial and/or femoral rotational deformity and cam/pincer lesions. It is important to consider tibial maltorsion as an aetiology of hip pain. Tibial derotation with DTDO results in significant clinical and functional recovery within 12 months in symptomatic hip impingement patients even in the presence of co-existing pathomorphology.

152 Leveraging Rfid Technology to Investigate the Genetic Associations Between Feeding Behavior and Leg Health in Floor-Raised Broilers

Abstract Leg disorders (LD) pose serious welfare issues in broiler chickens. The objective of this study was to investigate the suitability of using feeding behavior (FB) traits as potential leg health indicators in floor-raised broilers. The data used were recorded from 95,711 pure-line chickens of both sexes. The individual FB was monitored continuously on a feeder visit basis with a radio-frequency antenna system. The visit-log data were clustered into daily observations for different FB traits and averaged for the 1st week period after the trial started. The FB traits were daily feed intake (DFI1), number of visits (NV1), time spent at the feeder (TSF1), visiting activity interval (VAI1), number of visited feeders (NVF1), and walked distance visiting feeders (WD1). The LD traits were tibial dyschondroplasia (TD), hock-burn (HB), footpad (FP), rotated legs (RO), bowed-in (BI), and bowed-out (BO) leg structure deformities. Multi-trait linear-threshold models were fitted using Bayesian inference for estimating (co)variance components. The heritability (h2) posterior averages and standard deviations (within parentheses) ranged between 0.09 (0.01) and 0.52 (0.03) for LD traits, and between 0.09 (0.01) and 0.47 (0.02) for FB traits. Genetic correlations (rg) between FB and LD traits ranged from null to weak. TD presented negative rg with NV1 (-0.13), TSF1 (-0.14), NVF1 (-0.11), and WD1 (-0.14), indicating that some alleles involved in broiler activity are favorably associated with a potential reduction in the risk of TD-caused bone lesions. Conversely, FP presented unfavorable rg with the same traits (ranging from 0.21 to 0.32), except for TSF1 (-0.08). When compared with the remaining FB traits, DFI1 generally presented the opposite relationships with TD and FP, with positive (0.16) and negative (-0.18) genetic correlations observed for the first and the latter, respectively. Angular and rotational deformities (RO, BI, and BO) did not present significant correlations with FB traits, apart from the weak correlation found between BO and TSF1 (0.11). General activity indicators such as NV1, NVF1, and WD1 could represent earlier selection criteria to reduce TD incidence, although the potential undesired selection response for FP must be further investigated.

Machine learning-based stiffness optimization of digital composite metamaterials with desired positive or negative Poisson's ratio

Mechanical metamaterials such as auxetic materials have attracted great interest due to their unusual properties that are dictated by their architectures. However, these architected materials usually have low stiffness because of the bending or rotation deformation mechanisms in the microstructures. In this work, a convolutional neural network (CNN) based self-learning multi-objective optimization is performed to design digital composite materials. The CNN models have undergone rigorous training using randomly generated two-phase digital composite materials, along with their corresponding Poisson's ratios and stiffness values. Then the CNN models are used for designing composite material structures with the minimum Poisson's ratio at a given volume fraction constraint. Furthermore, we have designed composite materials with optimized stiffness while exhibiting a desired Poisson's ratio (negative, zero, or positive). The optimized designs have been successfully and efficiently obtained, and their validity has been confirmed through finite element analysis results. This self-learning multi-objective optimization model offers a promising approach for achieving comprehensive multi-objective optimization.

Seismic retrofit of low-rise structures using rotational viscoelastic dampers

In this research, the efficiency of a rotational viscoelastic seismic energy dissipation device is evaluated in a theoretical framework. Unlike conventional dampers which block the bays, the main advantage of this damper lies within its vertical installation scheme that provides open space in the bay and architectural flexibility. The proposed damper consists of a steel column with viscoelastic hinges at both ends that dissipate the seismic energy. Conventional viscoelastic dampers usually act under translational deformation, whereas it acts under rotational deformations in the considered scheme. The theoretical foundation is laid for the proposed damper and is verified by comparing the results with the analytical model of the damper. The developed device is proven to be versatile in terms of stiffness and energy dissipation which can be easily adjusted. The application and efficiency of this damper is validated by retrofitting a soft-first-story structure to fulfill the enhanced performance objective. The performance of the structure under a suite of earthquakes is compared before and after the seismic retrofit in terms of maximum interstory drift ratio and residual displacement.

Investigation on seismic performance of inclined Dou-Gong bracket between columns of ancient timber structures

To investigate the seismic behavior of the inclined Dou-Gong (DG) brackets, three full-scaled Dou-Gong bracket between columns with different inclinations along the width direction were tested under the pseudo-static test. The failure mode, hysteretic characteristic, stiffness degradation, deformation and energy dissipation capacity as well as the deformation modes of DG were discussed. Besides, numerical analysis of DG’s stress distribution and seismic behavior of DG brackets inclined in the overhanging direction was also studied. Parameter analysis was conducted to study the effect of frictional coefficient, vertical load and wood properties on the bearing capacity of DG. The results demonstrated that the DG bracket rotates as a whole and the relative slip of Da-Dou and Pingban-Fang leads to the shear damage of Mantou-tenon when DG failed. As the inclination in width and overhanging direction increases, the positive bearing capacity and lateral stiffness decrease, while the negative direction increases. The DG’s negative deformation ability is better than the positive direction and the larger the inclination, the stronger the deformation capacity. However, inclination reduces the energy dissipation capacity of DG. Rotation deformation is the main deformation mode of the DG bracket. Increasing the frictional coefficient, vertical load and compressive strength along the grain improves the bearing capacity of the DG, but the bearing capacity is slightly affected by the elastic modules along the grain. The research results can provide a scientific basis for the performance evaluation and repair protection of inclined DG brackets.

Clinical versus radiological method for adjusting rotational alignment during femoral shaft fractures intramedullary nailing and the malrotation impact on the functional outcomes: early results from a prospective cohort study

ObjectivesThe primary objective of the current study is to assess which is better for obtaining the proper femoral rotation during IMN of femoral fractures, the radiological or clinical method. The secondary objectives were to document malrotation's incidence and its effect on the hip and knee functional outcomes.MethodsThirty-three patients with unilateral femoral shaft fractures were treated using intramedullary nails (IMN) on a usual radiolucent operative table. Intraoperative rotation adjustment was performed using a radiological method (relying on the contralateral lesser trochanter profile) in 16 patients (group A), while in 17 patients, a clinical method was used (group B). Postoperative assessment of malrotation was performed using a CT scan, and 15 degrees was the cutoff value where below is an acceptable rotation (group I) and above is true malrotation (group II). Functional assessment was performed using the Harris hip score (HHS), the Tegner Lysholm Knee Scoring Scale (TLKSS), and the Neer score.ResultsThe patients' mean age was 30.7 ± 9.3 years; 81.8% were males, and the left side was injured in 63.6% of patients. After a mean follow up of 18.2 ± 6.9 months, all fractures were united, and the overall mean amount of rotational difference between the fractured and the contralateral side was 14.7° ± 6.0 (3–29.4), 84.8% were in external rotation. No difference in the mean rotational deformity in group A compared to group B. Measurements were 13.9 ± 6.7 and 15.7 ± 5.5, respectively (p = 0.47). Seventeen (51.5%) patients in group I with a mean deformity of 9.8 ± 3.4 (3–14.7), while group II consisted of 16 (48.5%) patients with a mean deformity of 19.6 ± 3.7 (15.3–29.4). There was no difference in the functional scores between group I and group II; HHS was 89.4 ± 7.4 versus 87.7 ± 8.9 (p = 0.54), TLKSS was 84.6 ± 9.6 versus 80.4 ± 13.9 (p = 0.32), and Neer score was 87.9 ± 9.5 versus 83 ± 12.5 (p = 0.21) for group I and group II, respectively.ConclusionThere was no difference in malrotation incidence after unilateral femoral fractures IMN with either an intraoperative clinical or radiological method for rotational adjustment; furthermore, malrotation did not affect the functional outcomes.

A reprogrammable mechanical metamaterial with origami functional-group transformation and ring reconfiguration

Recent advancements in reprogrammable metamaterials have enabled the development of intelligent matters with variable special properties in situ. These metamaterials employ intra-element physical reconfiguration and inter-element structural transformation. However, existing mono-characteristic homo-element mechanical metamaterials have limited reprogramming functions. Here, we introduce a reprogrammable mechanical metamaterial composed of origami elements with heterogeneous mechanical properties, which achieves various mechanical behavior patterns by functional group transformations and ring reconfigurations. Through the anisotropic assembly of two heterogeneous elements into a functional group, we enable mechanical behavior switching between positive and negative stiffness. The resulting polygonal ring exhibits rotational deformation, zero Poisson’s ratio stretching/compression deformation, and negative Poisson’s ratio auxetic deformation. Arranging these rings periodically yields homogeneous metamaterials. The reconfiguration of quadrilateral rings allows for continuous fine-tunability of the mechanical response and negative Poisson’s ratio. This mechanical metamaterial could provide a versatile material platform for reprogrammable mechanical computing, multi-purpose robots, transformable vehicles and architectures at different scales.

Use of external fixator combined with titanium elastic nails in the treatment of tibia shaft fractures in children

Tibia shaft fractures are common in all age groups. For these fractures; Conservative and surgical treatment methods are available. In surgical treatment, numerous surgical methods such as plate screw fixation, external fixator, and titanium elastic nail and K-wire fixation have been defined. The aim of the present study was to present the results of patients for whom external fixator combined with titanium elastic nails or titanium elastic nails alone were applied due to tibia shaft fractures. The study included 40 patients treated for tibia shaft fracture in our clinic between January 2016 and January 2019. Combined external fixator (EF) fixation was applied to patients who were found to be instable after Titanium elastic nail (TEN) application during the surgery. In clinical evaluation, Flynn classification, time to fracture union, fluoroscopy count, reoperation and time to full weight bearing were used. The results of patients for whom EF combined with TEN were applied were compared with the patients who had only TEN. Thirty patients were treated using TEN and 10 patients using EF combined with TEN. After 12 months of follow-ups, fracture union was achieved in all patients. There were 5% sagittal and 2.5% coronal plane angulation. Patients developed angular deformity of an average of 2.43 ± 1.9 degrees in the coronal plane and 2.65 ± 1.9 degrees in sagittal plane. Lower percentages of angular and rotational deformity were observed compared to the literature. Despite the disadvantages of using a greater number of fluoroscopy and longer operation periods in patients who underwent TEN+EF, these patients were mobilized earlier. It was concluded that combined EF application is a more feasible method in patients with pediatric tibia shaft fracture for whom stable fixation cannot be achieved with TEN.

Three-Dimensional Analysis of Windlass Mechanism Using Loading Computed Tomography in Patients With Hallux Rigidus and Healthy Volunteers

Category: Midfoot/Forefoot; Basic Sciences/Biologics Introduction/Purpose: The windlass mechanism (WM) increases the height of the medial longitudinal arch (MLA) of the foot by tensing the plantar aponeurosis during dorsiflexion of the metatarsophalangeal (MTP) joint. We speculated that this mechanism may be deeply involved in the pathogenesis of forefoot diseases such as hallux rigidus (HR). These conditions are three- dimensional (3D) deformities including rotational deformity, but the role of the WM has been evaluated only two-dimensionally by measuring the height of the navicular on lateral plain radiographs. The purpose of this study was to analyze in detail the WM of normal and HR feet in 3D. Methods: Participants were 14 patients with HR (17 feet) and 13 volunteers (21 feet). The volunteers had no history of foot disease or trauma, whereas the patients with HR had Coughlin and Shurnas classification I or II. Computed tomography (CT) of the foot with a load equivalent to the participant’s body weight was performed. Imaging was performed with the 1st MTP joint in the neutral position and dorsiflexed 30 degrees. 3D models were created using the software Mimics Research 17.0. Next, we used the iterative closest point (ICP) algorithm, which allows 3D objects to be superimposed without specifying anatomical feature points. Then, we performed 3D measurements of the (1) rotation of each bone in the MLA with respect to the tibia, (2) rotation of the distal bone in each joint of the MLA, and (3) changes in the height of the geometric center of the navicular. Results: At the calcaneus, navicular and medial cuneiform, the HR group showed less inversion, adduction than healthy group. (P &lt; 0.05) At the talonavicular joint, the navicular was 3.7° inversion, 2.9° adduction in the healthy group and 2.4°inversion, 1.3° adduction in the HR group. At the talocalcaneal joint, the calcaneus was 1.7° inversion, 1.5° adduction in the healthy group and 0.9°inversion, 0.6° adduction in the HR group. In the talonavicular and talocalcaneal joint, the HR group showed less inversion and adduction than control. (P &lt; 0.05) With dorsiflexion of the hallux, the height of the navicular increased by 2.1 mm in the healthy group and 1.3 mm in the HR group. There was a significant difference (P &lt; 0.05) between the two groups. Conclusion: In both groups, the calcaneus, navicular, and medial cuneiform bones moved not only in the sagittal plane but also in the frontal plane. But the movement of the talonavicular and talocalcaneal joints and the change in height of the navicular were significantly reduced compared with the healthy group. In other words, in the HR group, the motion of the midfoot and hindfoot was limited, suggesting that there may be a close relationship between WM dysfunction and midfoot and hindfoot motion. This study indicates that the dysfunction of the WM may have been a clue to the cause of HR.

Drop landing analysis of rotational osteotomies.

Pathomechanics resulting from rotational deformities of the long bones in an idiopathic population have not been extensively studied, and are chiefly limited to level over ground walking. Thirty-five adolescents with excessive idiopathic outward tibial torsion (TT), femoral rotation, or both (pan genu) were studied both before and after corrective surgery. Data collected included computational motion analysis of a drop jump and patient-reported outcomes consisting of PODCI and Goal Attainment Scores. Results were compared to an age-matched typically developing cohort (n = 25). Subjects with femoral anteversion (FA) exhibited compensatory hip rotations to normalize knee progression angles at landing. Subjects with only TT did not compensate at the hip, landing with typical knee progression but excessive outward foot progression. These strategies resulted in elevated frontal plane knee moments for FA ( P = 0.008), and elevated lateral knee forces in all groups compared to typical, with the TT group reaching significance ( P < 0.001). Rotational osteotomies successfully restored elevated kinematics and kinetics to within or below typically developing ranges. Patient-reported outcomes generally improved after surgery across all domains studied. Drop jump testing elucidated compensation strategies employed by these cohorts. Compensation did not fully alleviate elevated forces at the knees. Surgical intervention normalized pathokinematics and pathokinetics, reduced pain, and improved patients' perception of their functional abilities. Greater improvements were found in individuals in the two groups with FA compared to the group with TT only.

Hysteretic and rotational performance study of outwardly extending shape-steelprefabricated beam-column joints

This paper proposes fully-bolted extending shape steel prefabricated beam-column joints to achieve rapid construction and reliable connection of the precast reinforced concrete frame. The prefabricated component uses steel tube-concrete composite structures with outwardly extended shape steel, which achieves efficient installation and internal force transfer. Horizontal hysteresis tests were conducted on four components to determine the joint mode of failure and seismic performance index. The results show that the joint exhibits a “double plastic” failure mode, with plastic deformation occurring at the end of the reinforced concrete beam and buckling deformation at the shaped steel. Compared to cast-in-place joints, the new joints have a 30% increase in yield load, a 51% increase in peak load, an approximately 50% increase in initial stiffness, a 33% increase in equivalent viscous damping coefficient, and a ductility coefficient greater than 4.0. Analysis of strain showed that the stiffness of the connection area was too high, which will have a significant extrusion effect on the concrete at the end. Reducing the thickness of the steel plate in the joint space and weakening the shape stee by opening holes can significantly improve the rotational deformation capacity of the joint - further developing the plastic zone of reinforced concrete beams to improve the mechanical performance of the joint. Finally, the finite element model of the joint is established, and the numerical calculation is in good agreement with the experimental results. The research in this paper can provide technical support for the engineering application of the prefabricated joint.