Stem Extension Research Articles

Are asymmetric designs of tibial components superior to their symmetric counterparts for constrained condylar total knee arthroplasty using metal block augmentation?

PurposeIn total knee arthroplasty (TKA), asymmetric tibial components have been developed alongside symmetric tibial components to enhance bony coverage at the tibia. In primary TKA and revision TKA for patients with significant bone defects, augmentation is employed to fill the bone defect. However, there have been no reports on bony coverage of the tibial component of the revision system in the cases of bone defects. Therefore, we simulated bone defects using CT and compared the bony coverage of asymmetric and symmetric tibial components in the revision TKA system.MethodsThis study included 45 patients (50 knees involved) with medial osteoarthritis. Preoperative CT scans were used to simulate placement using ZedKnee. Three models were evaluated: Persona Revision PCCK (Zimmer) for the asymmetric component, NexGen LCCK (Zimmer) for the symmetric component, and the ATTUNE revision system (Depuy-Synthes). A 130-mm stem extension was utilized. Augmentations of each thickness were placed to simulate bone defects of 5, 10, and 15 mm. The coverage, overhang, and underhang rates were measured for each slice and compared among the models.ResultsIn terms of coverage, the rate was greater for PCCK at 0 mm, and only ATTUNE exhibited a significantly lower coverage at 5 and 10 mm. There was no significant difference in coverage at 15 mm. At 0 mm, PCCK demonstrated less posterior underhangs. At 5 and 10 mm, PCCK showed less anterior overhang but more anterior underhang. At 15 mm, PCCK had a less anterior overhang, with an overhang in the posterior region but less underhang. When overhang and underhang were combined and compared, the asymmetric component generally yielded superior results.ConclusionIn the cases of bone defects, asymmetric components demonstrated reduced anterior overhang and decreased posterior underhang, resulting in greater bone coverage. This may contribute to improved long-term outcomes in the revision TKA system.

Spring growth of lucerne (Medicago sativa L.) after different times of winter defoliation

The aim of this work was to determine if autumn/winter defoliation affected the time of lucerne stem extension in spring. Two experiments were established at the Field Research Centre, Lincoln University. Experiment 1 was established on 01/06/2022 using an existing two year old stand of “Force 4” lucerne. There were four canopy defoliation dates (1/06, 03/07, 17/07, 1/08). Experiment 2 repeated the treatments on the same paddock in the following year on eight defoliation dates (1/5, 15/5, 1/6, 15/6, 3/7, 17/7, 1/8 and 15/8). In both experiments, five stems were marked in each plot and stem height was measured weekly. The start of stem extension was unaffected by canopy defoliation date in either 2022 (P = 0.20) or 2023 (P = 0.17). Initiation of stem extension was triggered by a base photoperiod of 11.1 ± 0.2 h. This meant the thermal time accumulated from final defoliation to the start of stem extension differed among treatments. These results suggest the time of autumn/winter defoliation (the winter clean-up graze) will not affect the time of the first spring grazing, provided the developing basal buds are not removed. All stands reached 150 mm height by mid-September and produced 3.0 t/ha of dry matter by the end of the month. This suggests, grazing of the first paddock at Lincoln should commence in the first week of September to create a staggered start to rotational grazing that can maximise lucerne yield and quality for animal liveweight production.

Survey of Fungal Diseases on Barley, Wheat, and Oats at Tillering to Stem Extension Stages in Southern Regions of Korea during 2020-2021

Cereal, including barley, wheat, and oats, is a major winter food crop in Korea. Despite recent changes in agricultural environments in response to climate change, fungal diseases that could affect cereal productivity remain poorly understood. In this study, we investigated the incidence of diseases in barley, wheat, and oats in the southern part of Korea. We collected fungal pathogens from seven locations where cereals were grown. In March-April of 2020 and 2021, a total of 92 fungal isolates were collected, mainly from the stem base or leaves of cereal crops during the tillering and stem extension stages of cereals in Korea. The collected isolates were identified based on morphological and molecular biological characteristics. The dominant species was <i>Ceratobasidium cereale</i> (42.4%), followed by <i>Pyrenophora teres</i> (21.7%), <i>P. avenae</i> (10.9%), <i>Alternaria alternata</i> (6.5%), and <i>Epicoccum tobaicum</i> (6.5%). In addition, <i>P. tritici-repentis</i> (3.3%), <i>Cladosporium</i> sp. (3.3%), <i>Fusarium</i> sp. (3.3%), and <i>Nigrospora</i> sp. (2.2%) were also collected as minority groups. Our results will provide information on fungal pathogens that occur during the growing season of cereals in Korea, particularly during the tillering and stem extension stages. In addition, the isolates collected from this study can serve as a valuable resource for conducting simulations on climate change, focusing on temperature and humidity.

Effect of Adding Stem Extension to a Short-Keeled Knee Implant on the Risk of Tibial Loosening: a Historical Cohort Study.

Short-keeled tibial implants may be at higher risk of aseptic loosening. Stem augmentation has been suggested to improve its fixation. We aimed to assess whether this technique could decrease the loosening rate of such tibial implants. We retrospectively studied the knees receiving stemmed versus nonstemmed versions of a short-keeled prosthesis. A total of 932 patients undergoing total knee arthroplasty using a Persona prosthesis with >24-month follow-up (mean 53.7) were included, of whom 212 were at high risk of loosening due to osteoporosis or high body mass index (BMI). The rate of tibial aseptic loosening in high-risk patients and in the whole cohort was compared between those with and without stem extension. Multivariable analysis was conducted to identify the risk factors of loosening. In the whole cohort, in 203 knees (21.8%), a cemented short stem was used, versus 729 knees (78.2%) without. The tibial implant revision rates for loosening were 2.06% and 0.99% for nonstemmed and stemmed cases, respectively (P = 0.551). When the cohort was categorized based on the loosening risk factors, the loosening risk was significantly higher in the high-risk than in the low-risk group, regardless of stem status (log-rank test = 8.1, hazard ratio = 2.17, 95% CI = 1.78, 2.57, P = 0.005). 212 patients were at high risk of loosening, due to high BMI or osteoporosis, among whom the risk of aseptic loosening was higher when a stem was not used (log-rank = 32.1, hazard ratio = 4.95, 95% CI = 4.05, 5.86, P < 0.001). In multivariate analysis, osteoporosis, BMI ≥35, and smoking were correlated with loosening. The failure rate was markedly lower in the stemmed group of the patients at elevated risk of aseptic loosening due to osteoporosis and/or high BMI. In the entire cohort, the risk of loosening in stemmed tibial implants was similar to the nonstemmed group. The findings support a protective role for the stem in patients at high risk of failure of the cemented tibial implant. III therapeutic.

Current Evidence Does Not Support the Use of Tibial Stem Extension in Total Knee Arthroplasty of Obese Patients: A Systematic Review

BackgroundObesity rates have been increasing globally, leading to a higher incidence of knee osteoarthritis and a surge in primary and revision total knee arthroplasty (TKA). The debate continues on the impact of obesity on TKA success, particularly regarding the use of stemmed tibial components in obese patients. This systematic review aimed to compare the effectiveness of stemmed tibial components versus standard keeled tibial components in obese patients undergoing TKA. MethodsA systematic review was conducted using databases including PubMed, Embase, Scopus, and Web of Science from inception to December 2023. The eligibility criteria were Participants: Patients who have obesity undergoing TKA; Intervention: stemmed TKA; Comparator: standard keeled tibial TKA; Outcomes: aseptic loosening, patient-reported outcome measures (PROMs), and overall revision. Data extraction and quality assessment were performed using the Newcastle-Ottawa Scale for cohort studies and the Cochrane risk-of-bias tool for randomized trials. ResultsThe search yielded 470 studies, with 10 studies (42,533 knees) meeting the inclusion criteria. These studies included 3 randomized controlled trials and 7 retrospective cohorts. The primary outcomes measured were aseptic loosening and overall revision rates, while secondary outcomes included PROMs. Results indicated mixed findings, with some studies suggesting improved outcomes with stemmed components in cases of aseptic loosening and mechanical failure, while others showed no significant difference. The PROMs did not show a significant difference between groups post-TKA. The certainty of the evidence was graded as “very low” using the Grading of Recommendations, Assessment, Development, and Evaluations framework. ConclusionsCurrent literature does not provide conclusive evidence to support the routine use of stemmed tibial components in TKA for obese patients. The decision to use stem extensions should not solely rely on the patient’s obesity status. Further high-quality studies are needed to clarify the role of stemmed components in TKA for this patient population. Level of EvidenceIII.

Comprehensive evaluation of risk factors for aseptic loosening in cemented total knee arthroplasty: A systematic review and meta-analysis.

Aseptic loosening is the most common cause for revisions after total knee arthroplasty (TKA). Despite many studies exploring various risk factors associated with aseptic loosening, findings often present inconsistencies. To address this, we conducted a thorough review of the literature to identify and analyse these risk factors in cemented TKA. Additionally, we performed a meta-analysis to reconcile the divergent conclusions observed across studies. We searched PubMed, Web of Science and Embase from 1996 up to 2024 and evaluated the quality of the included literature. Seventy-four studies were included to assess the association of BMI, diabetes, high physical activity (HPA), osteoporosis, rheumatoid arthritis (RA), cement material and implant design. Twenty-nine studies were used to calculate relative risk and CIs (using the random effects theory) and study heterogeneity for six different risk factors (BMI, diabetes, HPA level, cement material, polyethylene and implant design). Patients with diabetes are eight times more likely to experience aseptic loosening compared to those without diabetes (RR = 9.18, 95% CI: 1.80-46.77, p < 0.01). The use of tibial stem extension or highly crosslinked polyethylene can help reduce the incidence of aseptic loosening. However, we did not identify BMI, HPA, osteoporosis, RA, the use of high-viscosity cement and the utilization of mobile-bearing designs as risk factors for aseptic loosening post-cemented TKA. Patients with diabetes undergoing TKA should be counselled regarding their potential increased risk of aseptic loosening. The use of tibial stem extensions and HXLPE can mitigate the incidence of aseptic loosening in cemented TKA. However, given a limited number of studies were included in the meta-analysis, we believe that higher-level studies are necessary to clearly identify other risk factors. Level III.

Biomechanical Effects of Stem Extension of Tibial Components for Medial Tibial Bone Defects in Total Knee Arthroplasty: A Finite Element Study.

The aim of this study was to investigate the biomechanical effects of stem extension with a medial tibial bone defect in primary total knee arthroplasty (TKA) on load distribution and stress in the proximal tibia using finite element (FE) analysis.FE simulations were performed on the tibia bone to evaluate the stress and strain on the tibia bone and bone cement. This was done to investigate the stress shielding effect, stability of the tibia plate, and the biomechanical effects in TKA models with various medial defects and different stem length models.The results demonstrated that in the bone defect model, the longer the stem, the lower the average von Mises stress on the cortical and trabecular bones. In particular, as the bone defect increased, the average von Mises stress on cortical and trabecular bones increased. The average increase in stress according to the size of the bone defect was smaller in the long stem than in the short stem. The maximal principal strain on the trabecular bone occurred mainly at the contact point on the distal end of the stem of the tibial implant. When a short stem was applied, the maximal principal strain on the trabecular bone was approximately 8% and 20% smaller than when a long stem was applied or when no stem was applied, respectively.The findings suggest that a short stem extension of the tibial component could help achieve excellent biomechanical results when performing TKA with a medial tibial bone defect.

Effect of Surgeon Volume on Mechanical Complications after Resection Arthroplasty with Articulating Spacer.

Two-stage revision with an antibiotic-loaded cement articulating spacer is a standard treatment for chronic prosthetic knee infection (PKI); however, mechanical complications can occur during the spacer period. There is limited evidence on the association between surgeon volume and mechanical complications after resection arthroplasty (RA) using an articulating spacer. This study aimed to compare the rates of mechanical complications and reoperation after RA with articulating spacers by surgeons with high volumes (HV) and low volumes (LV) of RA performed and analyzed the risk factors for mechanical failure. The retrospective study investigated 203 patients treated with PKIs who underwent RA with articulating spacers and were divided according to the number of RAs performed by the surgeons: HV (≥14 RAs/year) or LV (<14 RAs/year). Rates of mechanical complications and reoperations were compared. Risk factors for mechanical complications were analyzed. Of the 203 patients, 105 and 98 were treated by two HV and six LV surgeons, respectively. The mechanical complication rate was lower in HV surgeons (3.8%) than in LV surgeons (36.7%) (p < 0.001). The reoperation rate for mechanical complications was lower in HV surgeons (0.9%) than in LV surgeons (24.5%) (p < 0.001). Additionally, 47.2% of patients required hinge knees after mechanical spacer failure. Medial proximal tibial angle < 87°, recurvatum angle > 5°, and the use of a tibial spacer without a cement stem extension were risk factors for mechanical complications. Based on these findings, we made the following three conclusions: (1) HV surgeons had a lower rate of mechanical complications and reoperation than LV surgeons; (2) mechanical complications increased the level of constraint in final revision knee arthroplasty; and (3) all surgeons should avoid tibial spacer varus malalignment and recurvatum deformity and always use a cement stem extension with a tibial spacer.

Evaluation of a community-based, hybrid STEM family engagement program at pre-kindergarten entry

IntroductionThis article investigates an early STEM family engagement program offered during the pre-kindergarten (pre-k) year. Pre-k is an important juncture for community organizations to support children’s STEM engagement and parental involvement in informal STEM learning. We evaluated a program called Teaching Together STEM, which offers a series of museum outreach and family events at schools with the aim of broadening access to early STEM for children experiencing poverty. We replicated program content previously delivered using in-person events but shifted to a hybrid delivery approach that combined two virtual and two in-person events with linguistically diverse families of 3- and 4-year-olds. We evaluated whether attending events improved parent outcomes, such as involvement in STEM activities at home, and child outcomes, such as engagement in a STEM task.MethodsThe analytic sample included 59 families—35 randomly assigned families took part in the treatment and 24 families were assigned to a waitlist control group. Developed in Spanish and English, the informal STEM program was hosted by local children’s museum educators for 21 pre-k classrooms using these components: (a) a series of four family education “funshops;” (b) parent tips and reminders via text message; (c) nine thematically related, take-home STEM extension activity kits; and (d) a family museum field trip for each school, as well as individual family museum passes.ResultsThere were no significant impacts on primary outcomes of parent involvement (effect size [ES] = −0.03) or child STEM engagement/enthusiasm (ES = −0.73). There were improvements in some aspects of parents’ STEM attitudes (e.g., math expectancy ES = 0.58), but other distal parent and child outcomes were not significantly changed.DiscussionThe hybrid delivery approach showed promise in terms of attendance and parent satisfaction but likely was not intensive enough to increase parent involvement. We discuss implications for other community-based family engagement programs focused on broadening participation in informal STEM.

Utilizing Stems in Primary Total Knee Arthroplasty: Analysis of the Australian Orthopaedic Association National Joint Replacement Registry Data

BackgroundWe compared revision rates and reasons for revision for primary total knee arthroplasty (TKA) performed for osteoarthritis with and without tibial stem extensions. MethodsData from the Australian Orthopaedic Association National Joint Replacement Registry were used to compare all-cause revision, reason, and type of revision between primary TKA using stemmed tibial prostheses and non-stemmed prostheses. ResultsAll-cause revision for TKA with stem extension was higher for the first 6 months (hazard ratio [HR] 1.47; 95% confidence interval [CI]1.19 to 1.82; P < .001); while after 1.5 years TKA with stem extension had a lower rate of revision (HR 0.84; 95% CI 0.73 to 0.97; P = .01). Stemmed components were more likely to be revised for infection between 3 months and 1.5 years after surgery (HR 1.39; 95% CI 1.05 to 1.83; P = .02). The revision rate for aseptic loosening was lower in the stemmed group beyond 2 years (HR = 0.45; 95% CI 0.31 to 0.63; P < .001). Insert-only revision was higher in the stemmed group at all times (HR = 1.42; 95% CI 1.21 to 1.66, P < .001). Isolated tibial component revision was lower in the stemmed group at all times (HR 0.47; 95% CI 0.29 to 0.74; P = .001). Aseptic loosening for tibial component-only revision was significantly lower in the stemmed group at all times (HR 0.23; 95% CI 0.11 to 0.50; P < .001). ConclusionsPatients undergoing primary stemmed TKA have lower rates of all-cause revision beyond 1.5 years and tibial component-only revision at all times. Further investigation is required to preoperatively select patients that benefit from augmentation with stems.

TOTAL KNEE ARTHROPLASTY IN PATIENTS WITH OBESITY: A COMPARISON BETWEEN STEMMED, CEMENTLESS, AND UNSTEMMED TIBIAL COMPONENTS

AbstractObjectivesObesity is prevalent with nearly one third of the world's population being classified as obese. Total knee arthroplasty (TKA) is an effective treatment option for high BMI patients achieving similar outcomes to non-obese patients. However, increased rates of aseptic loosening in patients with a high BMI have been reported. In patients with high BMI/body mass there is an increase in strain placed on the implant fixation interfaces. As such component fixation is a potential concern when performing TKA in the obese patient. To address this concern the use of extended tibial stems in cemented implants or cementless fixation have been advocated. Extend tibial stems are thought to improve implant stability reducing the micromotion between interfaces and consequently the risk of aseptic loosening. Cementless implants, once biologic fixation is achieved, effectively integrate into bone eliminating an interface. This retrospective study compared the use of extended tibial stems and cementless implants to conventional cemented implants in high BMI patients.MethodsFrom a prospectively maintained database of 3239 primary Attune TKA (Depuy, Warsaw, Indiana), obese patients (body mass index (BMI) &gt;30 kg/m²) were retrospectively reviewed. Two groups of patients 1) using a tibial stem extension [n=162] and 2) cementless fixation [n=163] were compared to 3) a control group (n=1426) with a standard tibial stem cemented implant. All operations were performed by or under the direct supervision of specialist arthroplasty surgeons. Analysis compared the groups with respect to class I, II, and III (BMI &gt;30kg/m², &gt;35 kg/m², &gt;40 kg/m²) obesity. The primary outcome measures were all-cause revision, revision for aseptic loosening, and revision for tibial loosening. Kaplan-Meier survival analysis and Cox regression models were used to compare the primary outcomes between groups. Where radiographic images at greater than 3 months post-operatively were available, radiographs were examined to compare the presence of peri-implant radiolucent lines.ResultsThe mean follow-up of 4.8, 3.4, and 2.5 years for cemented, stemmed, and cementless groups respectively. In total there were 34 all-cause revisions across all the groups with revision rates of 4.55, 5.50, and 0.00 per 1000-implant-years for cemented, stemmed, and cementless groups respectively. Survival Analysis did not show any significant differences between the three groups for all-all cause revision. There were 6 revisions for aseptic loosening (5 tibial and 1 femoral); all of which were in the standard cemented implant group. In contrast there were no revisions in the stemmed or cementless implant groups, however, this was not significant on survival analysis. Analysis looking at class I, II, and III obesity also did not show any significant differences in survival for all cause revision or aseptic loosening.ConclusionThis retrospective analysis showed that there were no revisions required for aseptic loosening when either a cemented stemmed or cementless implant were used in obese patients. These findings are in line with other studies showing that cementless fixation or extended stem implants are a reasonable option in obese patients who represent an increasing cohort of patients requiring TKR.Declaration of Interest(b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Grain carbon isotopes indicate the ability of wheat plants to maintain enhanced intrinsic water-use efficiency even after short-term exposure to high temperatures and drought

Minimizing the impact of heat and drought on crop yields requires varieties with effective protective mechanisms. We tested the hypothesis that even a short-term high temperature amplifies the negative effects of reduced water availability on leaf gas-exchange, but can induce long-lasting improvement in plant water-use efficiency after the stress period. Accordingly, three common varieties of winter wheat (Triticum aestivum) were grown under field conditions. During the stem extension, the plants were exposed to distinct temperatures (daily maximum 26 vs. 38 °C), water availabilities (75% of field water capacity vs. permanent wilting point), and their combination for 14 days.All treatments reduced light-saturated rates of CO2 assimilation and transpiration, particularly when heat and drought were combined. Drought enhanced water-use efficiency (WUE) in all varieties (31.4–36.4%), but not at high temperatures (decrease by 17–52%). Intrinsic WUE (iWUE), determined from the stable carbon isotope composition of grains, was enhanced by 7.9–37% in all treatments and varieties; however, not all changes were significant. The combination of heat and drought tended to increase total protein content in grains but reduced spike productivity. Noticeably, the strongest decline in spike productivity was observed in Elan – the variety displaying the smallest enhancement of iWUE, while it was negligible in Pannonia which shows the most pronounced improvement of iWUE. We conclude that even several hot and dry days can improve iWUE for the rest of the vegetation season. This improvement, however, does not necessarily lead to increased crop productivity possibly due to physiological trade-offs.

Vegetative response to Verticillium dahliae of italian varieties of olive (Olea europaea L.)

Verticillium dahliae, the causal agent of vascular wilt, is a cosmopolitan pathogen of olive (Olea europaea L.). Italy is a traditional oil-producing country and its olive growing system is characterized by hundreds of regional varieties. They are widely employed for yielding oils protected by geographical indication systems of the European Union. The aim of this study was to evaluate the influence of V. dahliae on the vegetative growth of young, own-rooted olive plants under natural environmental conditions. Specifically, we analyzed differences in stem elongation, number of leaves and stem diameters in eight local varieties of the Campania region of Italy, plus a reference national cultivar, following artificially infection with a non-defoliating pathotype. Multivariate analysis indicated that a distinction in vulnerability among cultivar can be made considering the inhibitory effect of the fungus on stem extension growth, while the other parameters are less influential. Our work also illustrated the variability in some vegetative parameters among the Campanian germplasm and its influence on the inhibitory effect of the pathogen. Further studies will have to analyze the mechanisms connecting the morpho-physiological alterations with the pathogen invasion of the host tissue.

Econometrics Modelling Approach to Examine the Effect of STEM Policy Changes on Asian Student’s Enrollment Decision in USA

Academic research has shown significant interest in international student mobility, with previous literature primarily focusing on the migration industry from a political and public policy perspective. For many countries, international student mobility plays a crucial role in bolstering their economies through financial gains and attracting skilled immigrants. While previous studies have explored the determinants of mobility and country economic policies, only a few have examined the impact of policy changes on mobility trends. In this study, the researchers investigate the influence of immigration policy changes, particularly the optional practical training (OPT) extension on STEM programs, on Asian students' preference for enrolling in STEM majors at universities. The study utilizes observational data and employs a quasi-experimental design, analysing the information using the difference-in-difference technique. The findings of the research indicate that the implementation of the STEM extension policy in 2008 has a significant effect on Asian students' decisions to enroll in a STEM major. Additionally, the study highlights the noteworthy role of individual factors such as the specific STEM major, terminal degree pursued, and gender in influencing Asian students' enrollment decisions.

Stemmed Tibial Fixation for Primary Total Knee Arthroplasty in Obese Patients—A National Registry Study

BackgroundWe investigated if the use of augmented tibial fixation with stems in primary total knee arthroplasty (TKA) in obese patients was associated with a difference in reason for revision, type of revision, or overall revision rate. MethodsData from the Australian Orthopaedic Association National Joint Replacement Registry compared reason for revision, rate, and type of revision between primary TKA using stemmed tibial prostheses to nonstemmed prostheses, stratified by body mass index (BMI) and obesity. The cumulative percent revision was obtained using the Kaplan-Meier method, and Cox proportional hazards models estimated hazard ratios (HRs) adjusted for age and sex with 95% confidence intervals (CIs). All tests were 2-tailed at 5% statistical significance (P < .05). There were 66,508 procedures available for analyses. ResultsObese class 2 (BMI 35 to 39.99) had higher rates of revision in the stemmed group compared to the nonstemmed group (HR 1.44, 95% CI 1.00, 2.05, P = .047). There was no significant difference in revision rates between stemmed and nonstemmed tibial prostheses in any other BMI group. Primary TKA in obese patients (BMI ≥30) with a stem extension had a significantly higher rate of minor revisions compared to no stem extension (HR 1.31, 95% CI 1.03, 1.66, P = .025). There was no significant difference between stemmed and nonstemmed groups for major revision in obese patients and for minor or major revision in nonobese patients. ConclusionUsing a tibial stem during primary TKA in obese patients is not associated with a lower rate of revision.

The Response Characteristics of Sugarcane Yield, ET and WUE to Meteorological Drought Based on DSSAT-Canegro Model in Lai-bin, China

Crop water use efficiency is an important indicator of the scientific and rational nature of agricultural water use. Studying the response characteristics of sugarcane yield accumulation and water use efficiency to meteorological drought scenarios is a key scientific issue to promote smart management and sustainable development of China's sugarcane industry. In this paper, based on SPEI index, different meteorological drought scenarios were set and the DSSAT-Canegro model was used to simulate the response mechanisms of sugarcane yield accumulation and canopy evapotranspiration to irrigation regime scenarios under different meteorological drought scenarios. Furtherly, in this study, the total on-farm water use efficiency (WUEg), field water use efficiency (WP), true irrigation water use efficiency (WUEti), and irrigation water use efficiency (WUEi) of sugarcane in the study area were evaluated quantitatively to screen the optimal irrigation regime. Specific studies have shown that the stem extension stage is the most sensitive growth stage for sugarcane response to irrigation. Soil evapotranspiration and crop transpiration in sugarcane fields in Laibin varied with irrigation quotas, and that reducing soil evapotranspiration could improve sugarcane water use efficiency. In meteorological drought scenarios with longer and more intense droughts, irrigation has a stronger stimulating effect on sugarcane growth and is more favourable to its yield accumulation.The correlations between WUEg index and WP, WUEi) and WUEti indicators of sugarcane in the study area were all significant, which can be used as key analytical indicators for the optimization of sugarcane irrigation regimes in Laibin. The results of this study can provide important scientific support for the accurate quantification of water demand and consumption of sugarcane in southern China and their coupled and coordinated intelligent management.

Patient reported outcomes do not correlate to functional knee recovery and range of motion in total knee arthroplasty

BackgroundMany total knee arthroplasty (TKA) patients exhibit continued pain and limited function following surgery. Determining TKA outcomes is typically reliant on post-operative evaluations and completing patient-reported outcomes (PROMs). Due to low compliance rates, it is essential to identify new strategies for monitoring patients. The purpose of this analysis was to assess the correlations between gait kinematics, PROMs, and knee range of motion (ROM). Methods130 patients (75 female) received Persona IQ TKA (Zimmer Biomet, Warsaw, IN, USA) which includes a stem extension with embedded accelerometer and gyroscope. PROM scores were compared at baseline and 6 weeks post-TKA using a paired t-test. Gait kinematics were recorded daily via the Persona IQ stem extension. Pearson's correlation coefficients were derived between PROMs and average gait kinematics. ResultsKnee Injury and Osteoarthritis Outcome Score (KOOS Jr.) and Veterans RAND 12 (VR-12) physical scores improved following surgery (p ≤ 0.001, p = 0.003, respectively). Weak statistically significant correlations were found between PROMS and gait kinematics. ConclusionWeak correlations between PROMs and gait kinematics indicate patient perception of improvement and objectively measured functional status may not be interchangeable. Further, compliance with Persona IQ data reached 95.4–97.7% (depending on the parameter) at 6 weeks following surgery, a 20% higher compliance rate over PROMs. Daily functional measurements provide insight into the patient's progression and may be useful in detecting poor outcomes.

Management of proximal tibial stress fracture associated with advanced knee osteoarthritis: A systematic review

PurposeTibial stress fracture associated with knee osteoarthritis is an unusual and difficult clinical scenario. There is no clear existing treatment guideline for this uncommon clinical disease. The aim of this study is to review the impact of various treatment options for patients with advanced knee osteoarthritis associated with proximal tibial stress fracture. MethodsThe study was performed using the databases of PubMed and Scopus. Methodological index for non-randomized studies score was used to evaluate the included studies’ bias. The concluded data included the treatment approach, reported outcome measure, and time to fracture union. The literature search was started in December 2021 and accomplished in January 2022. A narrative description of the different methods and comparison of their results were done. ResultsOut of total assessed 69 studies, 9 studies were included in our review. The commonest treatment approach used was total knee arthroplasty by long tibial stem extension. The mean preoperative knee society score and knee functional score were 30.62 and 23.17, respectively. The mean postoperative knee society knee score was 86.87, while the functional score was 83.52. The average reported time to achieve fracture union was 4 months (a range of 2.07 – 5.50 months). ConclusionThe optimal clinical outcome for treating either acute or mobile tibial stress fracture in patients with advanced knee osteoarthritis can be achieved with long stem total knee arthroplasty. However, due to heterogeneity of data, comparison of different treatment options for chronic proximal tibial stress fracture mal-union/non-union coexisting with knee osteoarthritic and such inferences need to be judged cautiously.

Wheat Yield Gap Assessment in Using the Comparative Performance Analysis (CPA)

One of the crucial issues in developing nations is diminishing the yield gaps. Therefore, accurate yield gap estimation has many real-world uses for increasing crop production. Utilizing comparative performance analysis (CPA) techniques, the yield gap of wheat fields was evaluated in this study. In Varamin, Tehran Province, Iran, data on 104 wheat fields were collected between 2018 and 2020 and every aspect of wheat field management has been documented. The CPA model determines the yield gap’s contributing factors and potential yield. The results of data analysis revealed that the production ranged from 2600 to 7600 kg ha−1. The CPA method predicted a potential yield of 9316 kg ha−1 and found a yield gap of 3748 kg ha−1; this amount was 40.23% of the potential yield. Leaf chlorophyll (29%), irrigation at stem extension (9%), LAI (7.7%), soil salinity (8.2%), field area (16.3%), phosphorus consumption (6%), nitrogen utilized at the stage of tillering (16%), and HI (7.8%) all contributed to the yield gap in the CPA. It has been said that the computed yield in CPA is a potential yield that can be reached. CPA is a cheap and straightforward tool that could identify yield gaps and their causes in a district without the need for costly experiments. Therefore, developing nations with significant efficiency and yield gaps can use these techniques effectively.

Phenolic Compound Profile and Antioxidant Capacity of Flax (Linum usitatissimum L.) Harvested at Different Growth Stages.

The profile of phenolic compounds changes during the growth of a plant and this change affects its antioxidant potential. The aim of this research has been to find the growth stage of flax with the highest antioxidant capacity, and to determine the phenolic compounds responsible for such a capacity. Flax was harvested in six growth stages: from stem extension to mature seeds. The phenolic compounds were identified using LC-TOF-MS and quantified in an extract and in the fresh matter (FM) of each growth stage. The radical scavenging activity against ABTS•+ and DPPH•, the ferric-reducing antioxidant power (FRAP), and the antioxidant activity in the β-carotene-linoleic acid emulsion system were determined. Mono- and di-C-glycosyl flavones were found to be the most abundant phenolics of the aerial parts of flax, which also showed the highest content of isoorientin (210-538 µg/g FM). Coniferin, its derivative, and hydroxycinnamic acid derivatives were also detected. The plant was richer in flavone C-glycosides from stem extension to seed ripening (1105-1413 µg/g FM) than at the mature seed stage (557 µg/g FM). Most of the individual flavone C-glycoside contents in the extracts decreased when increasingly older plants were considered; however, the isoorientin content did not change significantly from the steam extension to the seed ripening stages. The antiradical activity against ABTS•+ and FRAP was higher for the aerial parts of the flax harvested at the flowering, brown capsule, and seed ripening stages, mainly due to the presence of flavone C-glycosides. The oxidation of β-carotene-linoleic acid emulsion was instead inhibited more effectively by the extracts from plants at the brown capsule and mature seed stages. Coniferin and its derivative were significantly involved in this activity. The extracts from the aerial parts of the flax harvested from flowering to seed ripening could be a valuable source of flavone C-glycosides for use as nutraceuticals and components of functional foods.