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Heterostructures of layered double hydroxides (LDHs) and MXenes have shown great promise for oxygen evolution reaction (OER) catalysts, owing to their complementary physical properties. Coupling LDHs with MXenes can potentially enhance their conductivity, stability, and OER activity. In this work, a scalable and straightforward in situ guided growth of CoFeLDH on Ti3C2Tx is introduced, where the surface chemistry of Ti3C2Tx dominates the resulting heterostructures, allowing tunable crystal domain sizes of LDHs. Combined simulation results of Monte Carlo and density functional theory (DFT) validate this guided growth mechanism. Through this way, the optimized heterostructures allow the highest OER activity of the overpotential = 301 mV and Tafel slope = 43 mV dec-1 at 10 mA cm-2, and a considerably durable stability of 0.1% decay over 200 h use, remarkably outperforming all reported LDHs-MXenes materials. DFT calculations indicate that the charge transfer in heterostructures can decrease the rate-limiting energy barrier for OER, facilitating OER activity. The combined experimental and theoretical efforts identify the participation role of MXene in heterostructures for OER reactions, providing insights into designing advanced heterostructures for robust OER electrocatalysis.

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BACKGROUND: Angular deformity in the lower extremity can result in pain, gait disturbance, cosmetic deformity and joint degeneration. Up until the introduction of guided growth, which has since become the widely accepted treatment for frontal plane angular angular deformity around the knee in skeletally immature patients, treatment consisted of staples, corrective osteotomy or an angular epiphysiodesis. Guided growth modulation uses the tension band principle with the goal of treatment being to normalise the lower limb mechanical axis resulting in lower morbidity than previous treatments. In order to assess the success of this procedure we reviewed our results in an attempt to identify patients who may not benefit from this elegant procedure. METHODS: We performed a retrospective review of prospectively collected surgical records and diagnostic imaging in our paediatric tertiary national referral centre to identify all patients who had guided growth surgery for coronal plane angular deformity of the knee from 2007 to 2023. We noted the patient demographics, diagnosis, peri-operative experience and outcome. All patients were followed until skeletal maturity, until their hardware was removed or at least 2 years. RESULTS: Two hundred thirty-six patients were assessed for eligibility. Of the 282 treated knees which met the criteria for final assessment 55 (19.5%) were unsuccessful. Complications were few but included infection and metal-work prominence. Procedures that were less likely to be successfully included growth disturbances following trauma (18.8% failure) or infection (40%), tumour (66.6%), mucopolysaccharidoses type I (15.7%), spondyloepiphyseal dysplasia (25%) or Blount's disease (60%). Idiopathic angular deformity showed an 89.5% success rate with guided growth. CONCLUSION: In our hands, guided growth had an 80.5% success rate when all diagnoses were considered. We continue to advocate the use of guided growth as a successful treatment option for skeletally immature patients with limb deformity however caution should be employed when considering its use in certain patient groups. LEVEL OF EVIDENCE: Level III, retrospective cohort study.

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Aims and objectives: Genu recurvatum deformity after treatment of leg-length discrepancy (LLD) with tension-band plating is a recognized, but poorly described phenomenon in medical literature. The aim of this study was to evaluate clinical and radiological features of patients treated with tension-band plating for LLD assessing the development of a recurvatum deformity and its relationship to plate and screw disposition in a transversal plane, thus attempting to establish optimal plate positioning. Materials and methods: Retrospective study of children with LLD treated with tension-band plating. Primary endpoints were clinical and radiological knee recurvatum and anterior and posterior physeal areas measured drawing a line spanning from the lateral to the medial tension-band plates in the transverse plane using volumetric magnetic resonance imaging (vMRI). These findings were compared between patients with and without knee recurvatum. Results: Twelve children (mean age 11.7 years) were included. Average follow-up was 2.6 years (1.5-5.0). Tension-band plating led to a significant reduction in LLD (mean, 15 mm). Six patients (50 %) developed clinical genu recurvatum (mean, 22°). According to vMRI, patients with genu recurvatum had a larger posterior to anterior physeal area ratio in both distal femur (1.6 versus 0.9, p < 0.05) and proximal tibial physes (2.2 versus 1.0, p < 0.05). Conclusion: The optimal position of the tension-band plates in distal femoral and proximal tibial physes should be in a point where a posterior to anterior physeal areas ratio is around 1.0, so as to achieve an even distribution of the physeal areas in the multidimensional physeal transverse plane. This point anatomically corresponds in the sagittal X-ray view to an imaginary line located just anterior to the posterior diaphyseal cortical bone on a true lateral radiograph for both femur and tibia.

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Purpose: Postoperative assessment of surgical interventions for correcting femoral rotational deformities necessitates a comparative analysis of femoral rotation pre- and post-surgery. While 2D assessment methods are commonly employed, ongoing debate surrounds their accuracy and reliability. To address the limitations associated with 2D analysis, we introduced and validated a 3D model-based analysis method for quantifying the angular and rotational impact of corrective rotational osteotomy in the growing femur. Methods: The method is based on surface registration of the pre- and post-intervention 3D femoral models. To this end, 3D triangulated surface models were generated using CT images for the right femurs of 11 skeletally immature pigs, each scanned at two distinct time points with a 12-week interval between scans. In our validation procedures, femoral corrective rotational osteotomy of the post-12-week femur was simulated at varying angles of 5, 10, 15 and 20 degrees in three dimensions. Subsequently, a surface 3D/3D registration-based approach was applied to determine the 3D femoral angulation and rotation between the two models to assess the method's detection accuracy of the predefined twist angles as ground truth references. Results: The results document the precision and accuracy of the registration-based method in evaluating rotation angles. Consistently high accuracy was observed across all angles, with an accuracy rate of 92.97% and a coefficient of variance of 8.14%. Conclusion: This study has showcased the potential for improving post-operative assessments with significant implications for experimental studies evaluating the effects of correcting rotational deformities in the growing femur. Level of Evidence: Not applicable.

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Precise synthesis of all-inorganic lead halide perovskite nanowire heterostructures and superlattices with designable modulation of chemical compositions is essential for tailoring their optoelectronic properties. Nevertheless, controllable synthesis of perovskite nanostructure heterostructures remains challenging and underexplored to date. Here, we report a rational strategy for wafer-scale synthesis of one-dimensional periodic CsPbCl3/CsPbI3 superlattices. We show that the highly parallel array of halide perovskite nanowires can be prepared roughly as horizontally guided growth on an M-plane sapphire. A periodic patterning of the sapphire substrate enables position-selective ion exchange to obtain highly periodic CsPbCl3/CsPbI3 nanowire superlattices. This patterning is further confirmed by micro-photoluminescence investigations, which show that two separate band-edge emission peaks appear at the interface of a CsPbCl3/CsPbI3 heterojunction. Additionally, compared with the pure CsPbCl3 nanowires, photodetectors fabricated using these periodic heterostructure nanowires exhibit superior photoelectric performance, namely, high ION/IOFF ratio (104), higher responsivity (49 A/W), and higher detectivity (1.51 × 1013 Jones). Moreover, a spatially resolved visible image sensor based on periodic nanowire superlattices is demonstrated with good imaging capability, suggesting promising application prospects in future photoelectronic imaging systems. All these results based on the periodic CsPbCl3/CsPbI3 nanowire superlattices provides an attractive material platform for integrated perovskite devices and circuits.

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Infantile Blount disease (IBD) is a pathologic varus knee deformity that, if left untreated, can lead to abnormal gait, limb length discrepancy, and pain. Traditionally, bracing and tibial osteotomy have been the primary treatments. More recently, guided growth with tension-band plating (TBP) has gained popularity, although there is a lack of data stratifying between the infantile, juvenile, and adolescent disease types. Therefore, the present review aims to determine the efficacy and complications of TBP in the IBD population. A systematic review was conducted following the PRISMA guidelines. Eligible studies included those focused on guided growth correction for IBD. Studies that did not stratify subjects by subgroup (infantile, juvenile, and adolescent) within their analysis were excluded. The outcomes of interest included demographic information, correction rate, failure rate, recurrence rate, and postoperative complications. Database review identified 541 studies. After screening, seven studies met our inclusion criteria, all of which were retrospective observational studies published between 2012 and 2022. In total, 92 limbs afflicted with Infantile Blount Disease underwent treatment with TBP. The recorded follow-up period ranged from four months to eight years. The age of patients at the time of surgery varied from 1.8 to nine years. On average, there was a 78.99% correction of deformities, with a range of 57.14% to 100%. Six studies provided data on failure and recurrence rates, with an average rate of 23.47%. Notably, infection and hardware failure emerged as the most prevalent postoperative complications, with mean rates of 11.44% and 9.50%, respectively. The average reoperation rate was 29.90%, with a range from 0.00% to 47.06%. The current literature shows a high rate of deformity correction with a relatively low risk of complications after TBP for IBD. Given the reported reoperation rates greatly varied, further data is needed to determine risk factors for reoperation following TBP. Our results suggest that guided growth with TBP may be a preferable first-line treatment for IBD.

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Background Rotational deformities in children are currently treated with an osteotomy, acute de-rotation, and surgical fixation. Meanwhile, guided growth is now the gold standard in pediatric coronal deformity correction. This study aimed to evaluate the feasibility of a novel implant intended for rotational guided growth (RotOs Plate) in a large porcine animal model. Methodology A submuscular plate was inserted on the medial and lateral aspect of the distal femoral physis of the left femur in 6 pigs. Each plate was anchored with a screw in the metaphysis and epiphysis respectively. The plates were expected to rotate the femur externally. The right femur acted as a control in a paired design. The animals were housed for 12 weeks after surgery. MRI scanning of both femora was performed before euthanasia after 12 weeks. Rotation was determined as the difference in the femoral version on MRI between the operated and non-operated femur after 12 weeks. Results External rotation in all operated femurs was observed. The mean difference in the femoral version on MRI between operated and non-operated femurs was 12.5° (range 9°-16°). No significant changes in axial growth were detected. Conclusions This study shows encouraging results regarding rotational guided growth, which may replace current invasive surgical treatment options for malrotation in children. However, further studies addressing potential secondary deformities are paramount and should be carried out.

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PURPOSE: Infantile scoliosis presents a significant challenge due to high risk of pulmonary complications and morbidity. While dual growing rod constructs are often utilized, they are not always feasible in a young patient with a severe curve. In this study, we present a series of eight patients treated with a unilateral magnetically controlled growing rod (uMCGR) construct later converted to guided growth surgery (GGS). METHODS: A multicenter database was queried for patients with progressive infantile scoliosis treated with uMCGR before later conversion to GGS. A minimum of 2 year follow-up was required for inclusion. Curve magnitude, trunk growth, revisions, and complications were tracked at all time points. RESULTS: Eight patients were included in the study. Mean age at index surgery was 4.1 years, while conversion to GGS occurred at average 7.9 years and final follow-up was at 10.5 years of age. At index procedure, major curve averaged 77.1°, which improved to 45.4°. Major curve increased to 48.4° prior to conversion, then improved to 30.9°. Major curve averaged 36.8° at final follow-up, for a maintained curve correction of 52.3%. T1-12 height and T1-S1 height averaged 15.4 and 21.5 cm at index procedure and increased to 20.6 and 32.7 cm at final follow-up. Nine revisions were performed in 6 patients, and no patient showed evidence of premature fusion. CONCLUSIONS: Treatment of severe progression infantile scoliosis with this staged protocol provided excellent curve correction with continued trunk growth through treatment, without evidence of the "Law of Diminishing Returns".

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PURPOSE: This study aims to compare the functional and radiological outcomes following both guided growth surgery (GGS) and acute corrective osteotomy (ACO) correction of angular deformities in children with rickets. METHODS: A total of 8 and 7 children who had gradual GGS and ACO correction, respectively, for angular deformities due to rickets from 2002 to 2022 were recalled for follow-up. Demographic data, types of rickets, data on pharmacological treatment, biochemical parameters, recurrence of angular deformity and postoperative complications were obtained from the medical records. A radiographic evaluation of the leg was performed to determine the tibiofemoral angle. For functional evaluation, the Active Scale for Kids (ASK) and Lower Extremity Functional Scale (LEFS) instruments were used for children below and above 15 years old, respectively. RESULTS: In terms of the tibiofemoral angle, the GGS group documented greater angle changes compared to the ACO group, but the difference was not significant. In terms of functional outcomes, the overall score percentage of both groups was comparable with the GGS group showing a trend of higher score percentage compared to the ACO group. The GGS group presented no complication while 2 neurovascular injuries and 1 implant failure were recorded in the ACO group. CONCLUSION: Both GGS and ACO procedures resulted in similar radiographic and functional outcomes for the treatment of rickets in children. GGS may be advantageous in terms of reducing complications of surgery. Nevertheless, the choice of surgical intervention should be made based on the patient's circumstances and the surgeon's preference.

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PURPOSE: Implant-mediated guided growth (IMGG) is used to address coronal plane deformity in skeletally immature patients. Few studies have reported on IMGG and simultaneous medial patellofemoral ligament (MPFL) reconstruction for paediatric patients with concurrent genu valgum and patellofemoral instability (PFI). This study aimed to report on the outcomes of these simultaneous procedures. MATERIALS AND METHODS: This was a retrospective review of paediatric patients undergoing simultaneous MPFL reconstruction and IMGG between 2016 and 2023. Mechanical lateral distal femoral angle (mLDFA), hip-knee-ankle angle (HKA) and mechanical axis deviation (MAD) were measured on full-length hip-to-ankle plain radiographs. Measurements were taken preoperatively, prior to implant removal and/or at final follow-up with minimum 1-year clinical follow-up. RESULTS: A total of 25 extremities in 22 patients (10 female) underwent simultaneous IMGG and MPFL reconstruction. The mean age at surgery was 12.6 ± 1.7 years. The mean duration of implant retention was 18.6 ± 11.3 months. Nineteen extremities (76%) underwent implant removal by final follow-up. Preoperative HKA corrected from a mean of 5.8 ± 2.3° to -0.8 ± 4.5° at implant removal or final follow-up (p < 0.001), with mLDFA and MAD similarly improving (both p < 0.001). HKA corrected a mean of 0.7 ± 0.9° per month, while mLDFA and MAD corrected a mean of 0.5 ± 0.6°/month and 2 ± 3 mm/month, respectively. At the time of implant removal or final follow-up, 88% of patients demonstrated alignment within 5° of neutral. Only one extremity experienced subsequent PFI (4%). For 14 patients who underwent implant removal with further imaging at a mean of 7.8 ± 4.9 months, only one patient (7%) had a valgus rebound to an HKA > 5°. CONCLUSION: Simultaneous MPFL reconstruction and IMGG provided successful correction of lower extremity malalignment with only one recurrence of PFI. This approach is a reliable surgical option for skeletally immature patients with genu valgum and PFI. LEVEL OF EVIDENCE: Level 4 case series.

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BACKGROUND: There is a higher rate of failure of isolated MPFL reconstruction in skeletally immature patients with patellar instability compared to skeletally mature patients. Genu valgum is a known risk factor for patellar instability. There is potential for concomitant surgical correction of genu valgum to achieve better clinical outcomes and to decrease failure rates of MPFL reconstruction. PURPOSE: To evaluate outcomes of combined medial patellofemoral ligament (MPFL) reconstruction and implant-mediated guided growth (IMGG) in skeletally immature patients with patellar instability and genu valgum. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: In a multicenter study, all skeletally immature patients with recurrent patellar instability and genu valgum who underwent MPFL reconstruction using hamstring graft and IMGG using a transphyseal screw or tension band plate for the distal femur and/or proximal tibia were included. The knee valgus angle and mechanical axis were measured on full-length radiographs and anatomic risk factors were measured on MRI. Patients were followed until correction of their lower limb alignment and implant removal or until skeletal maturity. Clinical outcomes, including complications, were analyzed. RESULTS: A total of 31 patients (37 knees) were included in the study. The mean age and skeletal age of the cohort were 12.4 and 12.9 years, respectively. Simultaneous MPFL reconstruction and IMGG were performed in 26 of 37 knees; 11 underwent staged procedures. Twenty knees had transphyseal screws and 17 knees had tension band plates for IMGG. The knee valgus corrected from a mean of 12.4° to 5.1° in 12.1 months. Implants were removed from 22 of 37 knees once genu valgum was corrected. There was no significant difference (P = .65) in the correction rate between plates (0.7 deg/month) and screws (0.6 deg/month). Ten complications occurred in 4 patients (7 knees) and included 5 patellar redislocations, 2 rebound valgus, 1 varus overcorrection, 1 knee arthrofibrosis, and 1 implant loosening. For children <10 years of age, 3 of 6 (50%) knees had patellar redislocations and 5 of 6 knees had a complication. This was statistically significant (P = .003) compared with patients >10 years of age. Similarly, for patients with bilateral knee involvement, 5 of 12 (42%) knees had patellar redislocations and a total of 8 complications occurred in this subset. This was statistically significant (P < .001) compared with patients with unilateral involvement. CONCLUSION: IMGG with plates or screws in the setting of combined MPFL reconstruction improves genu valgum. Children <10 years of age and those with bilateral instability with genu valgum remain difficult subsets to treat with higher complication rates.

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Purpose: The objective of this scoping review was to describe the extent and type of evidence of using guided growth to correct rotational deformities of long bones in children. Methods: This scoping review was conducted in accordance with the JBI methodology for scoping reviews. All published and unpublished studies investigating surgical methods using guided growth to perform gradual rotation of long bones were included. Results: Fourteen studies were included: one review, three clinical studies, and ten preclinical studies. In the three clinical studies, three different surgical methods were used on 21 children. Some degree of rotation was achieved in all but two children. Adverse effects reported included limb length discrepancy (LLD), knee stiffness and rebound of rotation after removal of tethers. Of the ten preclinical studies, two were ex vivo and eight were in vivo. Rotation was achieved in all preclinical studies. Adverse effects reported included implant extrusions, LLD, articular deformities, joint stiffness and rebound of rotation after removal of tethers. Two of the studies reported on histological changes. Conclusions: All studies conclude that guided growth is a potential treatment for rotational deformities of long bones. There is great variation in animal models and surgical methods used and in reported adverse effects. More research is needed to shed light on the best surgical guided growth method, its effectiveness as well as the involved risks and complications. Based on current evidence the procedure is still to be considered experimental. Level of evidence: 4.

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Introduction: Distal tibia fractures are a common cause of physeal injuries that can subsequently cause deformity in pediatric populations. Limited literature exists supporting treatment strategies for varus deformities. In this study, we illustrate a unique case of premature physeal closure complicated by development of a varus ankle deformity treated with navigation guided physeal bar resection that spontaneously resolved without the requirement for guided growth. Case Report: A 6-year-old female presented to our clinic after development of a right ankle varus deformity measuring 14°. She had sustained a right Salter Harris type 3 distal tibia fracture 10 months prior and underwent fixation at an external facility. After undergoing navigation guided physeal bar resection, resolution of her deformity occurred without the use of guided growth. Conclusion: Spontaneous resolution of an ankle deformity is possible after a physeal bar resection. However, in these technically demanding procedures, it is important to optimize accuracy and results using preoperative bar mapping and intraoperative three-dimensional navigation.

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Bone and joint angular deformities are common pediatric orthopedic problems that are often corrected surgically. Previous studies successfully demonstrated proximal femoral growth modulation in animal models, however outcome measurements were limited by two-dimensional analysis. In this study, six Yorkshire cross male piglets were treated with unilateral percutaneous transphyseal screw placement across the medial aspect of the proximal femoral physis and analyzed using three-dimensional (3D) techniques. Three primary outcome measures were considered-physis angle, version, and femoral length. Compared to paired controls, all treated femurs displayed varus correction and shortening after an average treatment period of 10 weeks. The amount of varus change was 11.6 ± 2.8° (mean ± SD) (p = 0.0002, 95% confidence interval [CI] [8.659, 14.589]) and shortening was 4.3 ± 1.6 mm (p = 0.0011, 95% CI [2.672, 5.942]). Four animals demonstrated retroversion and two demonstrated anteversion compared to controls (4.1 ± 5.4° retroversion, p = 0.1169, 95% CI [-1.483, 9.765]). The amount of varus correction was strongly correlated with the orientation of the screw relative to the medial/lateral axis of the physis (r = -0.887, p = 0.0183, 95% CI [-0.988, -0.271]). The amount and direction of version was strongly correlated with how eccentrically anterior or posterior the screw was placed relative to the center of the physis (r = -0.850, p = 0.0322, 95% CI [-0.983, -0.123]) as well as the angle of the screw relative to the posterior condylar axis of the femur (r = -0.980, p = 0.0006, 95% CI [-0.998, -0.822]). This study is the first to use 3D analysis to quantify proximal femur growth modulation and identify associations between the growth modulation outcomes and screw placement parameters.

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The guided-growth strategy has been widely explored and proved its efficacy in fabricating surface micro/nanostructures in a variety of systems. However, soft materials like polymers are much less investigated partly due to the lack of strong internal driving mechanisms. Herein, the possibility of utilizing liquid crystal (LC) ordering of smectic liquid crystal polymers (LCPs) to induce guided growth of surface topography during the formation of electrohydrodynamic (EHD) patterns is demonstrated. In a two-stage growth, regular stripes are first found to selectively emerge from the homogeneously aligned region of an initially flat LCP film, and then extend neatly along the normal direction of the boundary line between homogeneous and homeotropic alignments. The stripes can maintain their directions for quite a distance before deviating. Coupled with the advanced tools for controlling LC alignment, intricate surface topographies can be produced in LCP films starting from relatively simple designs. The regularity of grown pattern is determined by the LC ordering of the polymer material, and influenced by conditions of EHD growth. The proposed approach provides new opportunities to employ LCPs in optical and electrical applications.

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Purpose: The conditions leading to growth rebound after hemiepiphysiodesis are still poorly understood. This article analyzes the radiographical outcomes after guided growth with tension band plating, using plates in idiopathic genu valgum patients and attempts to generate a predictive model of growth rebound. Methods: Patients with idiopathic genu valgum deformity who received tension band plating were selected for evaluation. We only analyzed coronal plane deformities. Only patients with a long-standing X-ray before tension band plating surgery, a long-standing X-ray at tension band plating removal, and a long-standing X-ray at the latest follow-up after tension band plating removal were considered for this study. The change of mechanical axis deviation between the tension band plating removal and the last follow-up was evaluated for rebound, and ordinal logistic regression was performed to determine the relevant variables for predictive modeling rebound growth. Results: Overall, 100 patients (189 legs) were analyzed. The mean mechanical axis deviation at tension band plating removal was 8.4 mm in varus direction, and the mean mechanical axis deviation at the last follow-up was -3.4 mm (p ≤ 0.001). However, 111 legs (59%) showed rebound growth, 57 (30%) stayed stable, and 21 (11%) showed a continuous correction. Six significant factors significantly influencing rebound were isolated which are clinically relevant: sex, age, baseline mechanical axis deviation, mechanical lateral distal femoral angle, and mechanical medial proximal tibial angle, and mechanical axis deviation correction rate. Mechanical axis deviation correction rate had the highest odds ratios. The machine learning classification model for predicting rebound growth built from the study data showed a misclassification rate of 39%. Conclusion: There was a high rate of rebound growth in this cohort, especially for patients at a young age at implantation. The highest risk factors for rebound growth were male sex, and high correction rates, such as found during peak growth spurt. The proposed classification model needs more data to improve its predictive power before it can be used in clinics. Level of evidence: Level III.

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Introduction: Correction of knee malalignment by guided growth using a tension-band plate is a common therapy to prevent knee osteoarthritis among other things. This approach is based on the Hueter-Volkmann law stating that the length growth of bones is inhibited by compression and stimulated by tension. How the locally varying mechanical loading of the growth plate is influenced by the implant has not yet been investigated. This study combines load cases from the gait cycle with personalized geometry in order to investigate the mechanical influence of the tension-band plates. Methods: Personalized finite element models of four distal femoral epiphyses of three individuals, that had undergone guided growth, were generated. Load cases from the gait cycles and musculoskeletal modelling were simulated with and without implant. Morphological features of the growth plates were obtained from radiographs. 3D geometries were completed using non-individual Magnetic Resonance Images of age-matched individuals. Boundary conditions for the models were obtained from instrumented gait analyses. Results: The stress distribution in the growth plate was heterogenous and depended on the geometry. In the insertion region, the implants locally induced static stress and reduced the cyclic loading and unloading. Both factors that reduce the growth rate. On the contralateral side of the growth plate, increased tension stress was observed, which stimulates growth. Discussion: Personalized finite element models are able to estimate the changes of local static and cyclic loading of the growth plate induced by the implant. In future, this knowledge can help to better control growth modulation and avoid the return of the malalignment after the treatment. However, this requires models that are completely participant-specific in terms of load cases and 3D geometry.

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Leg length discrepancies (LLD) are frequently associated with coronal malalignment. Temporary hemiepiphysiodesis (HED) is a well-established procedure for the correction of limb malalignment in skeletally immature patients. For treatment of LLD > 2 cm, lengthening with intramedullary devices gains increasing popularity. However, no studies have investigated the combined application of HED and intramedullary lengthening in skeletally immature patients. This retrospective single-center study evaluated the clinical and radiological outcomes of femoral lengthening with an antegrade intramedullary lengthening nail combined with temporary HED performed in 25 patients (14 females) between 2014 and 2019. Temporary HED through the implantation of flexible staples of the distal femur and/or proximal tibia was either performed prior (n = 11), simultaneously (n = 10) or subsequently (n = 4) to femoral lengthening. The mean follow-up period was 3.7 years (±1.4). The median initial LLD was 39.0 mm (35.0-45.0). Twenty-one patients (84%) presented valgus and four (16%) showed varus malalignment. Leg length equalization was achieved in 13 of the skeletally mature patients (62%). The median LLD of the eight patients with residual LLD > 10 mm at skeletal maturity was 15.5 mm (12.8-21.8). Limb realignment was observed in nine of seventeen skeletally mature patients (53%) in the valgus group, and in one of four patients (25%) in the varus group. Combining antegrade femoral lengthening and temporary HED is a viable option to correct LLD and coronal limb malalignment in skeletally immature patients; however, achieving limb length equalization and realignment may be difficult in cases of severe LLD and angular deformity, in particular.

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Correction of cubitus varus is commonly attempted through supracondylar humeral osteotomy. We hypothesized that lateral distal humeral hemiepiphysiodesis (LDHH) could be used to gradually correct this deformity in children. We conducted a retrospective study including all patients who underwent LDHH with the eight-Plate system between 2008 and 2018, with a minimum 4-year follow-up. We collected demographic, fracture-related, pre- and postoperative clinical (carrying angle (CA), ROM), and radiological data (humeral-ulnar angle (HUA), Baumann angle (BA), shaft-condylar angle (SCA), lateral capitellohumeral angle (LCHA)), as well as data on complications and satisfaction at last follow-up. Fifteen patients were included, with a median follow-up of 81 (64-103) months. All the variables had improved significantly as follows: CA -16 (-18 to -9)°, HUA -16 (-19 to -12)°, BA -11 (-17 to -7)°, SCA 7.5 (3.3 to 13.8)°, LCHA -4.8 (-6.8 to 0.6), flexion 10 (0 to 24)°, and extension 10 (0 to 10)°. The annual correction rate in terms of HUA was 2.41° (1.9 to 3.2). There were 5 cases of aseptic screw loosening, 4 of them requiring replacement, without relation to age at surgery (p = 0.324). Most patients (86.67%) were satisfied, and a relationship was found with younger age at surgery (p = 0.037). In conclusion, preliminary results show that LDHH with the eight-Plate system is an effective technique for mild to moderate cubitus varus deformity correction in children. Patients should be advised of the relatively long duration of implant retention and the possibility of reoperation for screw replacement or implant removal.

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INTRODUCTION: Distal Anterior Tibial Guided Growth has been shown to be useful to correct recurrent equinus deformity after open surgical release for Congenital Talipes Equinovarus. This has not been evaluated in a recurrence after use of the Ponseti method, where soft tissue releases are currently understood as the mainstay of treatment. METHODS: Patients with recurrence of equinus component of CTEV, who underwent DATGG with at least 6-month follow-up were identified retrospectively. The criteria for performing this procedure were (1) equinus not correctable to neutral passively (2) the feeling of a bony block to dorsiflexion clinically as evidenced by a supple Achilles' tendon at maximum dorsiflexion and (3)a finding of a flat-top talus radiologically. Successful treatment was defined by the achievement of heel strike on observation of gait. Details of the index procedure including concurrent procedures, any complications and their treatment, past and subsequent treatment episodes were retrieved from electronic patient records. Pre-op and last available post-op X-rays were evaluated for change in the anterior distal tibial angle and for flat-top talus deformity. RESULTS: We identified 22 feet in 16 patients, with an average follow-up was 25 (8.8-47.3) months. The mean aDTA changed from 88.9 (82.3-94.5) to 77.0 (65.0-83.9) degrees, which was statistically significant (p < 0.0001) using the Paired t-test. Clinically, 17 feet (77 %) obtained a plantigrade foot with a normal heel strike. Complications were identified in 5 feet and include staple migration, oversized staple, superficial infection, iatrogenic varus deformity. Recurrence after completed treatment was noted in one foot. CONCLUSION: This procedure should form a part of the armamentarium of procedures for treating equinus component of CTEV recurrences even in feet not treated previously by open procedures. When used in patients without significant surgical scarring it helps to address bony and soft-tissue factors, leading to effective treatment. LEVEL OF EVIDENCE: Therapeutic Level IV.

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