Prediction of Footplate Position after Implantable Collamer Lens Implantation Based on Iris and Ciliary Body Morphologies.

PURPOSE: To investigate the factors affecting footplate position and its influence on vault characteristics following implantable collamer lens (ICL) implantation. SETTING: Hunan Provincial People's Hospital, Changsha, China. DESIGN: Retrospective case series. METHODS: This study included 124 patients (124 eyes). Ultrasound biomicroscopy (UBM) was performed to assess the iris and ciliary body morphologies and observe the footplate position. Using multiple linear regression, the relationship between various ocular and ICL parameters and the vault as well as the factors affecting the footplate distance (FD) were analyzed. Based on the FD, three groups were formed: group 1 (<500 µm), group 2 (500-1000 µm), and group 3 (>1000 µm). The distribution of the vault range after surgery was observed for the three groups. RESULTS: Ciliary sulcus angle and FD significantly impacted the vault (adjusted R2=0.190, F=6.763, P<0.001), with FD being the most important factor influencing the vault (Beta=-0.383, P<0.001). Postoperative UBM revealed that the footplate was located at different positions in the posterior chamber, with the majority (52%) being located on the ciliary body. The average size of the four footplate orientations was 0.88±0.24 mm. Multiple linear regression analysis revealed that ciliary body thickness (CBT), iris curvature (IC), and ICL iris contact length (IRCL) significantly influenced the FD (adjusted R2=0.373, F=11.432, P<0.001). The vault range differed significantly among the three groups (X2=32.33, P<0.001). CONCLUSIONS: Different postoperative ICL footplate positions significantly affect the vault. CBT, IC, and IRCL can alter the position of the footplate from the expected position. This study provides reference for ICL size selection and vault prediction.

Pre-expanded Brachial Artery Perforator Propeller Flap: An Addition to the Armamentarium for Postburn Axillary Contracture Reconstruction.

BACKGROUND: Postburn axillary contracture is a common complication that leads to functional impairment and unsatisfactory aesthetic outcomes. This article aims to present our experience with axillary contracture reconstruction using pre-expanded brachial artery perforator propeller (BAPP) flaps and provide a systematic review of other regional or free flaps. METHODS: This retrospective study included patients who underwent postburn axillary contracture reconstruction using pre-expanded BAPP flaps from 2015 to 2022. Data on the flap characteristics and function of the affected shoulders were recorded. A systematic review was conducted by retrieving studies that assessed the outcomes of regional or free cutaneous/fasciocutaneous flaps for treating axillary contracture from PubMed, Web of Science, EMBASE, and Scopus published before October 1, 2023. RESULTS: Twelve pre-expanded BAPP flaps measuring up to 26 cm × 11 cm (mean, 116.9 cm 2) survived completely with no major complications, and the donor sites were closed primarily. The average range of shoulder abduction increased from 77.9° to 141.7° (p=0.002). The systematic review included 34 articles, reporting 12 regional and three free flaps. The most reported flaps were the thoracodorsal artery perforator flap, scapular flap, and parascapular flap. The overall complication rate ranged from 0 to 25%, and the average change in shoulder abduction ranged from 72.5° to 99.4°. CONCLUSIONS: Pre-expanded BAPP flaps can be effectively used for reconstructing postburn anterior axillary fold contracture. The donor site availability and the specific axillary contracture type should be considered when selecting a regional or free flap.

Single-Atom Titanium on Mesoporous Nitrogen, Oxygen-Doped Carbon for Efficient Photo-thermal Catalytic CO2 Cycloaddition by a Radical Mechanism.

Developing efficient and earth-abundant catalysts for CO2 fixation to high value-added chemicals is meaningful but challenging. Styrene carbonate has great market value, but the cycloaddition of CO2 to styrene oxide is difficult due to the high steric hindrance and weak electron-withdrawing ability of the phenyl group. To utilize clean energy (such as optical energy) directly and effectively for CO2 value-added process, we introduce earth-abundant Ti single-atom into the mesoporous nitrogen, oxygen-doped carbon nanosheets (Ti-CNO) by a two-step method. The Ti-CNO exhibits excellent photothermal catalytic activities and stability for cycloaddition of CO2 and styrene oxide to styrene carbonate. Under light irradiation and ambient pressure, an optimal Ti-CNO produces styrene carbonate with a yield of 98.3 %, much higher than CN (27.1 %). In addition, it shows remarkable stability during 10 consecutive cycles. Its enhanced catalytic performance stems from the enhanced photothermal effect and improved Lewis acidic/basic sites exposed by the abundant mesopores. The experiments and theoretical simulations demonstrate the styrene oxide⋅+ and CO2⋅- radicals generated at the Lewis acidic (Tiδ+) and basic sites of Ti-CNO under light irradiation, respectively. This work furnishes a strategy for synthesizing advanced single-atom catalysts for photo-thermal synergistic CO2 fixation to high value products via a cycloaddition pathway.

Extensive Defect Reconstruction Using Multiple Perforator Propeller Flaps in a Jigsaw Puzzle Approach.

BACKGROUND: Reconstruction of extensive defects remains challenging for plastic surgeons. We report our experience with extensive defect reconstruction using multiple perforator propeller flaps and provide a systematic review of the literature on this approach. METHODS: This retrospective study included patients who underwent defect reconstruction with multiple perforator propeller flaps from 2014 to 2021. A systematic review was conducted by retrieving studies on reconstructive strategy from PubMed, Web of Science, EMBASE, and Scopus published before December 1, 2022. RESULTS: Thirty patients underwent defect reconstruction using 65 perforator propeller flaps. The posterior trunk (66.7%) was the most common site of defects. Complete flap survival was achieved in 61 flaps (93.8%). Partial necrosis of four flaps in three patients and venous congestion of one flap resulted in an overall complication rate of 13.3%. One flap experienced distal tip necrosis in 21 patients undergoing posterior trunk or perineal defect reconstruction, leading to an overall complication rate of 4.7%. Other complications were observed during the reconstruction of defects in the lower extremities (one of five patients) and anterior trunk (two of four patients). In the systematic review, 11 articles involving 74 patients were identified. The commonly reported locations of the defects were the perineum (55.4%) and posterior trunk (33.8%). Flap-related complications included venous congestion, and no flaps were lost. CONCLUSIONS: This study on the use of multiple perforator propeller flaps in a jigsaw puzzle approach demonstrated that the method can be effectively used for extensive posterior trunk and perineal defect reconstruction.

Exploring the therapeutic potential of Sirt6-enriched adipose stem cell-derived exosomes in myocardial ischemia-reperfusion injury: unfolding new epigenetic frontiers.

BACKGROUND: The management of myocardial ischemia-reperfusion injury (MIRI) presents continuous therapeutic challenges. NAD-dependent deacetylase Sirtuin 6 (Sirt6) plays distinct roles in various disease contexts and is hence investigated for potential therapeutic applications for MIRI. This study aimed to examine the impact of Sirt6-overexpressing exosomes derived from adipose stem cells (S-ASC-Exo) on MIRI, focusing on their influence on AIM2-pyroptosis and mitophagy processes. The sirtuin family of proteins, particularly Sirtuin 6 (Sirt6), play a pivotal role in these processes. This study aimed to explore the potential therapeutic effects of Sirt6-enriched exosomes derived from adipose stem cells (S-ASC-Exo) on regulating MIRI. RESULTS: Bioinformatic analysis revealed a significant downregulation of Sirt6 in MIRI subjected to control group, causing a consequential increase in mitophagy and pyroptosis regulator expressions. Therefore, our study revealed that Sirt6-enriched exosomes influenced the progression of MIRI through the regulation of target proteins AIM2 and GSDMD, associated with pyroptosis, and p62 and Beclin-1, related to mitophagy. The introduction of S-ASC-Exo inhibited AIM2-pyroptosis while enhancing mitophagy. Consequently, this led to a significant reduction of GSDMD cleavage and pyroptosis in endothelial cells, catalyzing a deceleration in the progression of atherosclerosis. Extensive in vivo and in vitro assays were performed to validate the expressions of these specific genes and proteins, which affirmed the dynamic modulation by Sirt6-enriched exosomes. Furthermore, treatment with S-ASC-Exo drastically ameliorated cardiac functions and limited infarct size, underlining their cardioprotective attributes. CONCLUSIONS: Our study underscores the potential therapeutic role of Sirt6-enriched exosomes in managing MIRI. We demonstrated their profound cardioprotective effect, evident in the enhanced cardiac function and attenuated tissue damage, through the strategic modulation of AIM2-pyroptosis and mitophagy. Given the intricate interplay between Sirt6 and the aforementioned processes, a comprehensive understanding of these pathways is essential to fully exploit the therapeutic potential of Sirt6. Altogether, our findings indicate the promise of Sirt6-enriched exosomes as a novel therapeutic strategy in treating ischemia-reperfusion injuries and cardiovascular diseases at large. Future research needs to underscore optimizing the balance of mitophagy during myocardial ischemia to avoid potential loss of normal myocytes.

The Role of Breast Cancer Cells in Bone Metastasis: Suitable Seeds for Nourishing Soil.

PURPOSE OF REVIEW: The purpose of this review was to describe the characteristics of breast cancer cells prone to developing bone metastasis and determine how they are regulated by the bone microenvironment. RECENT FINDINGS: The bone is a site of frequent breast cancer metastasis. Bone metastasis accounts for 70% of advanced breast cancer cases and remains incurable. It can lead to skeletal-related events, such as bone fracture and pain, and seriously affect the quality of life of patients. Breast cancer cells escape from the primary lesion and spread to the bone marrow in the early stages. They can then enter the dormant state and restore tumourigenicity after several years to develop overt metastasis. In the last few years, an increasing number of studies have reported on the factors promoting bone metastasis of breast cancer cells, both at the primary and metastatic sites. Identifying factors associated with bone metastasis aids in the early recognition of bone metastasis tendency. How to target these factors and minimize the side effects on the bone remains to be further explored.

Simultaneous Hydrogen Generation and Exciplex Stimulated Emission in Photobasic Carbon Dots.

Photocatalytic water splitting is a promising approach to generating sustainable hydrogen. However, the transport of photoelectrons to the catalyst sites, usually within ps-to-ns timescales, is much faster than proton delivery (∼µs), which limits the activity. Therefore, the acceleration of abstraction of protons from water molecules towards the catalytic sites to keep up with the electron transfer rate can significantly promote hydrogen production. The photobasic effect that is the increase in proton affinity upon excitation offers means to achieve this objective. Herein, we design photobasic carbon dots and identify that internal pyridinic N sites are intrinsically photobasic. This is supported by steady-state and ultrafast spectroscopic measurements that demonstrate proton abstraction within a few picoseconds of excitation. Furthermore, we show that in water, they form a unique four-level lasing scheme with optical gain and stimulated emission. The latter competes with photocatalysis, revealing a rather unique mechanism for efficiency loss, such that the stimulated emission can act as a toggle for photocatalytic activity. This provides additional means of controlling the photocatalytic process and helps the rational design of photocatalytic materials.

Long-Term clinical results of patellofemoral arthroplasty for isolated patellofemoral osteoarthritis.

OBJECTIVES: The aim of this study was to explore the clinical outcomes and long-term survival of patellofemoral arthroplasty in treatment of isolated patellofemoral osteoarthritis. METHODS: We retrospectively studied a total of 46 type Y-L-Q PFAs that were designed at our institution in 38 patients. Implant survivorship was analyzed with a follow-up of 18.9-29.6 years. Knee Society Score (KSS), Oxford Knee Score (OKS), and University of California Los Angeles activity scale (UCLA) were used to assess functional outcomes. RESULTS: The implant survivorship was 83.6% at 15 years, 76.8% at 20 years, and 59.4% at 25 years 14 PFAs in 12 patients were revised into total knee arthroplasty at 16.0 ± 6.7 years; 13 for progression of tibiofemoral osteoarthritis and one for polyethylene wear. The mean Knee Society Score objective scores and functional scores were 73.0 ± 17.5 (range, 49-95) and 56.4 ± 28.9 (range, 5-90), respectively. The mean Oxford Knee Score was 25.8 ± 11.5 (range, 8-44). CONCLUSION: Type Y-L-Q patellofemoral arthroplasty can be an effective method for treating isolated patellofemoral osteoarthritis with satisfactory survival.

Comparison of risk of complication between neuraxial anaesthesia and general anaesthesia for hip fracture surgery: a systematic review and meta-analysis.

BACKGROUND: Controversy remains over the choice of anaesthetic technique for patients undergoing surgery for hip fracture. AIM: The aim was to compare the risk of complication of neuraxial anaesthesia with that of general anaesthesia in patients undergoing hip fracture surgery. METHODS: This systematic review was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines and was registered at PROSPERO (CRD42022337384). The study included eligible randomised controlled trials published before February 2022. Data synthesis was performed to compare the differences between general and neuraxial anaesthesia. Meta-regression analysis was performed to investigate the influence of the publication year. A subgroup analysis was performed based on patient age and the anaesthetic technique used. A grading of recommendations, assessment, development and evaluations assessment was performed to assess the quality of each outcome. RESULTS: Twenty randomised controlled trials and 4802 patients were included. Data synthesis revealed significant higher risk of acute kidney injury in the general anaesthesia group ( P =0.01). There were no significant differences between the two techniques in postoperative short-term mortality ( P =0.34), delirium ( P =0.40), postoperative nausea and vomiting ( P =0.40), cardiac infarction ( P =0.31), acute heart failure ( P =0.34), pulmonary embolism ( P =0.24) and pneumonia ( P =0.15). Subgroup analysis based on patient age and use of sedative medication did not reveal any significant differences. Meta-regression analysis of the publication year versus each adverse event revealed no statistically significant differences. CONCLUSION: A significantly higher risk of postoperative acute kidney injury was found in patients receiving general anaesthesia. This study revealed no significant differences in terms of postoperative mortality and other complications between general and neuraxial anaesthesia. The results were consistent across the age groups.

Acetabular Diameter Assessment and Three-Dimensional Simulation for Acetabular Reconstruction in Dysplastic Hips.

BACKGROUND: This study aimed to investigate the relationship between acetabular width, three-dimensional (3D) simulation, and surgical results in total hip arthroplasty patients who have developmental dysplasia of the hip (DDH). METHODS: This retrospective study included 216 DDH cases. Inner and outer acetabular width (OAW) was measured at the plane passing through the center of acetabular fossa. 3D simulation and 2D standard templating were performed. The actual cup size and the use of augments during surgery were recorded. Association among the indices and their distribution in different types of DDH were analyzed. RESULTS: A difference of 13 to 14 millimeters (mm) was found between the inner acetabular width and actual cup size used in type II, III, and IV cases, while the difference was 0.2 to 3.6 mm for OAW. The accuracy of 2D templating and 3D simulation in predicting cup size was comparable in Crowe type I (86.5 versus 76%, P = .075), type II (72.7 versus 51.5%, P = .127), and type III (93.3 versus 66.7%, P = .169). The 3D simulation was significantly more accurate in Crowe type IV (89.1% versus 60.9%, P = .001). Augments and bone grafts were significantly more commonly used in type II (25%) than in the other types (0 to 6.5%). CONCLUSION: OAW more accurately predicted actual cup size than inner acetabular width. The supero-lateral acetabular bone defects in type II cases require additional attention. Compared with 2D templating, 3D simulation is more accurate in predicting actual cup size in dysplastic hips with severe deformity and may be recommended in these selected cases, especially for Crowe IV patients.

Computer Navigation Assisted Restricted Kinematic Alignment Improves Short-Term Outcomes in Total Knee Arthroplasty: An Ambispective Cohort Study.

OBJECTIVES: Mechanical alignment (MA)-total knee arthroplasty (TKA) has been challenged due to the excessive soft tissue release and the evidence of the clinical outcomes of computer assisted navigation is still limited. The aim of this ambispective cohort study was to: (i) investigate whether computer assisted navigation is capable to achieve restricted kinematic alignment (rKA)-TKA; and (ii) compare the short-term outcomes between rKA-TKA and MA-TKA. METHODS: We retrospectively included 41 patients diagnosed with osteoarthritis who received MA-TKA between April 2019 and January 2021 and 43 patients diagnosed with osteoarthritis who received rKA-TKA were included in the prospective cohort from January 2021 to September 2021. Demographical, peri-operative, and radiological data were collected and compared. Unpaired two-sample t-test for continuous variables and χ2 test for categorical variables were used to compare various measurements in two groups. The patient-reported outcome measures at baseline, 10 days (T1), and 6 months (T6) after surgery were statistically analyzed by generalized estimating equation (GEE) models. RESULTS: Fourty-one patients (45 knees) and 43 patients (48 knees) were included in the MA and the rKA group respectively. Three constitutional knee phenotypes (II, I, IV) were the commonest in our population. Navigation improved the surgical accuracy (1.5° vs 3.5°, p < 0.001) and precision (interquartile range 4.0 vs 2.0, p < 0.001) in the rKA group than the MA group. The changes in Knee Injury and Osteoarthritis Outcome Score 12 (KOOS12), EuroQol five-dimension questionnaire (EQ5D) from baseline to T1 and T6 for patients with on-target rKA were larger than on-target MA counterparts (26.053 vs 18.607, P < 0.001(KOOS12, T1) , 0.457 vs 0.367 p < 0.001(EQ5D, T1) ; 51.017 vs 46.896, P = 0.023(KOOS12, T6) , 0.606 vs 0.565, P = 0.01(EQ5D, T6) ). Patients with on-target rKA had better Forgotten Joint Score (FJS) at T1 (54.126 vs 40.965, P = 0.002) compared with on-target MA counterparts. CONCLUSIONS: Computer assisted navigation achieved the level of accuracy required by rKA-TKA. rKA-TKA offered significantly better short-term outcomes than MA-TKA.

Artificially Intelligent Three-Dimensionally-Printed Patient-Specific Instrument Improves Total Hip Arthroplasty Accuracy.

BACKGROUND: Patient-specific instrumentation (PSI) has the potential to improve the accuracy of implant positioning in total hip arthroplasty (THA). This prospective clinical study aimed to develop artificial intelligence to increase PSI production efficiency and assess accuracy, clinical outcomes, and learning curves. METHODS: A convolutional neural network was applied to automatically process computer tomography images. PSI size and position were designed to guide the acetabular preparation and femoral neck resection. Thirty patients who underwent PSI-assisted THAs were matched to thirty patients who underwent free-hand THAs, and the component positions, as well as radiographic and clinical outcomes were analyzed. RESULTS: PSI-assisted THA was significantly more accurate than free-hand THA at achieving the target component position. The mean absolute errors of cup inclination (P = .004) and anteversion (P < .001) were significantly smaller in the PSI group with fewer outliers. Calcar length (P = .002) and neck length (P = .026) were also more accurate in the PSI group. The leg length discrepancy was significantly lower in the PSI group (P = .002). There were no significant differences in operation time, blood loss, leg length discrepancy, or cup position among the first, second, and last 10 cases. CONCLUSION: PSI-assisted THA offered more accurate component positions and better radiographic outcomes than free-hand THA. There was no evidence of a learning curve. Our findings suggest that PSI is a convenient and practical option to help surgeons achieve accurate surgical outcomes.

Early prediction of clinical scores for left ventricular reverse remodeling using extreme gradient random forest, boosting, and logistic regression algorithm representations.

Objective: At present, there is no early prediction model of left ventricular reverse remodeling (LVRR) for people who are in cardiac arrest with an ejection fraction (EF) of ≤35% at first diagnosis; thus, the purpose of this article is to provide a supplement to existing research. Materials and methods: A total of 109 patients suffering from heart attack with an EF of ≤35% at first diagnosis were involved in this single-center research study. LVRR was defined as an absolute increase in left ventricular ejection fraction (LVEF) from ≥10% to a final value of >35%, with analysis features including demographic characteristics, diseases, biochemical data, echocardiography, and drug therapy. Extreme gradient boosting (XGBoost), random forest, and logistic regression algorithm models were used to distinguish between LVRR and non-LVRR cases and to obtain the most important features. Results: There were 47 cases (42%) of LVRR in patients suffering from heart failure with an EF of ≤35% at first diagnosis after optimal drug therapy. General statistical analysis and machine learning methods were combined to exclude a number of significant feature groups. The median duration of disease in the LVRR group was significantly lower than that in the non-LVRR group (7 vs. 48 months); the mean values of creatine kinase (CK) and MB isoenzyme of creatine kinase (CK-MB) in the LVRR group were lower than those in the non-LVRR group (80.11 vs. 94.23 U/L; 2.61 vs. 2.99 ng/ml; 27.19 vs. 28.54 mm). Moreover, AUC values for our feature combinations ranged from 97 to 94% and to 87% when using the XGBoost, random forest, and logistic regression techniques, respectively. The ablation test revealed that beats per minute (BPM) and disease duration had a greater impact on the model's ability to accurately forecast outcomes. Conclusion: Shorter disease duration, slightly lower CK and CK-MB levels, slightly smaller right and left ventricular and left atrial dimensions, and lower mean heart rates were found to be most strongly predictive of LVRR development (BPM).

Insight on Reaction Pathways of Photocatalytic CO2 Conversion.

Photocatalytic CO2 conversion to value-added chemicals is a promising solution to mitigate the current energy and environmental issues but is a challenging process. The main obstacles include the inertness of CO2 molecule, the sluggish multi-electron process, the unfavorable thermodynamics, and the selectivity control to preferable products. Furthermore, the lack of fundamental understanding of the reaction pathways accounts for the very moderate performance in the field. Therefore, in this Perspective, we attempt to discuss the possible reaction mechanisms toward all C1 and C2 value-added products, taking into account the experimental evidence and theoretical calculation on the surface adsorption, proton and electron transfer, and products desorption. Finally, the remaining challenges in the field, including mechanistic understanding, reactor design, economic consideration, and potential solutions, are critically discussed by us.

Primary Sjögren's syndrome is not associated with poor outcomes after total hip arthroplasty: a retrospective case-control study with a matched cohort of osteoarthritis patients.

INTRODUCTION: The number of patients with primary Sjögren's syndrome (PSS) requiring total hip arthroplasty (THA) is expected to increase, but few studies have detailed their outcomes. The purpose of this study was to evaluate a THA cohort of patients with avascular necrosis of the femoral head (ANFH) who had PSS and to compare their outcomes with those of matched patients with osteoarthritis. METHOD: A case-control study using data from a single-institution arthroplasty registry was performed. Forty-two THAs in 32 patients undergoing THA with a diagnosis of PSS were identified and were matched with 84 THAs in 64 patients with osteoarthritis (1:2 ratio). Functional and health-related quality of life (QoL) evaluations were performed, and complications were recorded at the last follow-up. Logistic regression was used to determine factors associated with reaching the transfusion trigger of hemoglobin < 8 g/dL (TT8) in PSS patients. RESULTS: After a mean 5-year follow-up, both cohorts had similar hip function and health-related QoL outcomes. The incision complications and reaching TT8 were greater in the PSS group. No differences were observed in the rate of 90-day readmission, reoperation, or overall revision. By multivariate analysis, the influencing factors for reaching TT8 in PSS patients were lower preoperative hemoglobin (OR = 0.842, 95% CI [0.741-0.958], P < 0.05). CONCLUSION: Our study demonstrated PSS patients who received THA due to ANFH could achieve clinical outcomes similar to those of non-PSS patients. Improving preoperative Hb level can reduce the risk of transfusion. Key Points • THA significantly improved hip function and health-related quality of life in PSS patients with osteonecrosis of the femoral head. • Patients with PSS were more likely to reach the transfusion trigger and higher rates of incision complications after THA. • Improving preoperative Hb level can reduce the risk of transfusion for PSS patients who underwent THA.

Surgical treatment of femoroacetabular impingement in a patient with Stickler syndrome: a case report.

Stickler syndrome is a multisystem connective tissue disorder caused by mutations in collagen genes that can present with craniofacial, ocular, audial, or skeletal abnormalities. Here, we report on a male patient with a COL2A1 missense mutation (c.647G>A; p.Gly216Asp). He complained of an out-toeing gait and restricted hip mobility. Radiographs showed broad and elongated femoral necks with coxa valga. An alpha angle of 119° and 96° for his left and right femur, respectively, and almost no femoral head-neck offset, suggested a femoroacetabular impingement. Considering the patient's unwillingness to receive a total hip replacement for his Tönnis grade 2 hips, we intended to establish impingement-free hips by causing minimizing trauma. Therefore, we performed an osteochondroplasty of femoral head-neck junction and gluteal muscle release without correcting coxa valgus through the surgical hip dislocation approach. The range of motion of his hips improved as the surgery restored the femoral head-neck offset. However, the patient experienced a sense of lower limb length disparity and hip instability, which might be caused by his uncorrected proximal femoral deformity. This case presents the previously unreported phenotypic features of a COL2A1 mutation G216D. Orthopedic surgeons should consider genetic disorders when confronting atypical abnormalities. Moreover, the primary deformity should be corrected in hip preservation surgeries. Insufficient deformity correction might contribute to unsatisfactory surgical outcomes.

Validation of CT-Based Three-Dimensional Preoperative Planning in Comparison with Acetate Templating for Primary Total Hip Arthroplasty.

OBJECTIVE: This study aims to compare the accuracy of CT-based preoperative planning with that of acetate templating in predicting implant size, neck length, and neck cut length, and to evaluate the reproducibility of the two methods. METHODS: This prospective study was conducted between August 2020 and March 2021. Patients who underwent elective primary total hip arthroplasty by a single surgeon were assessed for eligibility. The included patients underwent both acetate templating and CT-based planning by two observers after the operation. Each observer conducted both acetate templating and CT-based planning twice for each case. The outcome measures included the following: (1) the accuracy of surgical planning in predicting implant size, calcar length, and neck length, which was defined as the difference between the planned size and length and the actual size and length; (2) reproducibility of the two planning techniques, which were assessed by inter-observer and intra-observer reliability analysis; (3) the influence of potential confounding factors on planning accuracy, which was evaluated using generalized estimating equations. RESULTS: A total of 57 cases were included in the study. CT-based planning was more accurate than acetate templating for predicting cup size (93% vs 79%, p < 0.001) and stem size (93% vs 75%, p < 0.001). When assessed by mean absolute difference, the comparison between acetate templating and CT-based planning was 4.28 mm vs 3.74 mm (p = 0.122) in predicting neck length and 3.05 mm vs 2.93 mm (p = 0.731) in predicting neck cut length. In the inter-observer reliability analysis, an intraclass correlation coefficient (ICC) of 0.790 was achieved for predicting cup size, and an ICC of 0.966 was achieved for predicting stem size using CT-based planning. In terms of intra-observer reliability, Observer 1 achieved an ICC of 0.803 for predicting cup size and 0.965 for predicting stem size in CT-based planning. Observer 2 achieved ICC values of 0.727 and 0.959 for predicting cup and stem sizes, respectively. The average planning time was 6.48 ± 1.55 min for CT-based planning and 6.12 ± 1.40 min for acetate templating (p = 0.015). CONCLUSION: The CT-based planning system is more accurate than acetate templating for predicting implant size and has good reproducibility in total hip arthroplasty.

Development and Validation of an Artificial Intelligence Preoperative Planning System for Total Hip Arthroplasty.

Background: Accurate preoperative planning is essential for successful total hip arthroplasty (THA). However, the requirements of time, manpower, and complex workflow for accurate planning have limited its application. This study aims to develop a comprehensive artificial intelligent preoperative planning system for THA (AIHIP) and validate its accuracy in clinical performance. Methods: Over 1.2 million CT images from 3,000 patients were included to develop an artificial intelligence preoperative planning system (AIHIP). Deep learning algorithms were developed to facilitate automatic image segmentation, image correction, recognition of preoperative deformities and postoperative simulations. A prospective study including 120 patients was conducted to validate the accuracy, clinical outcome and radiographic outcome. Results: The comprehensive workflow was integrated into the AIHIP software. Deep learning algorithms achieved an optimal Dice similarity coefficient (DSC) of 0.973 and loss of 0.012 at an average time of 1.86 ± 0.12 min for each case, compared with 185.40 ± 21.76 min for the manual workflow. In clinical validation, AIHIP was significantly more accurate than X-ray-based planning in predicting the component size with more high offset stems used. Conclusion: The use of AIHIP significantly reduced the time and manpower required to conduct detailed preoperative plans while being more accurate than traditional planning method. It has potential in assisting surgeons, especially beginners facing the fast-growing need for total hip arthroplasty with easy accessibility.

Interfacial Manganese-Doping in CsPbBr3 Nanoplatelets by Employing a Molecular Shuttle.

Mn-doping in cesium lead halide perovskite nanoplatelets (NPls) is of particular importance where strong quantum confinement plays a significant role towards the exciton-dopant coupling. In this work, we report an immiscible bi-phasic strategy for post-synthetic Mn-doping of CsPbX3 (X=Br, Cl) NPls. A systematic study shows that electron-donating oleylamine acts as a shuttle ligand to transport MnX2 through the water-hexane interface and deliver it to the NPls. The halide anion also plays an essential role in maintaining an appropriate radius of Mn2+ and thus fulfilling the octahedral factor required for the formation of perovskite crystals. By varying the thickness of parent NPls, we can tune the dopant incorporation and, consequently, the exciton-to-dopant energy transfer process in doped NPls. Time-resolved optical measurements offer a detailed insight into the exciton-to-dopant energy transfer process. This new approach for post-synthetic cation doping paves a way towards exploring the cation exchange process in several other halide perovskites at the polar-nonpolar interface.

A Multi-Layer Device for Light-Triggered Hydrogen Production from Alkaline Methanol.

It usually requires high temperature and high pressure to reform methanol with water to hydrogen with high turnover frequency (TOF). Here we show that hydrogen can be produced from alkaline methanol on a light-triggered multi-layer system with a very high hydrogen evolution rate up to ca. 1 µmol s-1 under the illumination of a standard Pt-decorated carbon nitride. The system can achieve a remarkable TOF up to 1.8×106  moles of hydrogen per mole of Pt per hour under mild conditions. The total turnover number (TTN) of 470 000 measured over 38 hours is among the highest reported. The system does not lead to any COx emissions, hence it could feed clean hydrogen to fuel cells. In contrast to a slurry system, the proposed multi-layer system avoids particle aggregation and effectively uses light and Pt active sites. The performance is also attributed to the light-triggered reforming of alkaline methanol. This notable performance is a promising step toward practical light-driven hydrogen generation.