Heterogeneous elasticity drives ripening and controls bursting kinetics of transcriptional condensates.

Many biomolecular condensates, including transcriptional condensates, are formed in elastic mediums. In this work, we study the nonequilibrium condensate dynamics in a chromatin-like environment modeled as a heterogeneous elastic medium. We demonstrate that the ripening process in such an elastic medium exhibits a temporal power-law scaling of the average condensate radius, depending on the local stiffness distribution and different from Ostwald ripening. Moreover, we incorporate an active process to model the dissolution of transcriptional condensates upon RNA accumulation. Intriguingly, three types of kinetics of condensate growth emerge, corresponding to constitutively expressed, transcriptional-bursting, and silenced genes. Furthermore, the simulated burst frequency decreases exponentially with the local stiffness, through which we infer a lognormal distribution of local stiffness in living cells using the transcriptome-wide distribution of burst frequency. Under the inferred stiffness distribution, the simulated distributions of bursting kinetic parameters agree reasonably well with the experimental data. Our findings reveal the interplay between biomolecular condensates and elastic mediums, yielding far-reaching implications for gene expression.

Ultrasound had high accuracy in measuring hip joint capsule thickness.

BACKGROUND: The hip joint capsule is an essential component of hip joint function and stability, and its thickness is closely associated with certain medical conditions, surgical outcomes, and rehabilitation treatments. Currently, in clinical practice, hip joint capsule thickness is predominantly measured using magnetic resonance imaging (MRI), with limited utilization of ultrasound examinations for this purpose. METHODS: We retrospectively evaluated patients who visited our Sports Medicine Department between February 2017 and March 2023 and underwent both hip joint MRI and ultrasound imaging on the same side. All patients had undergone preoperative hip joint MRI and ultrasound examinations, with the time gap between the two examinations not exceeding three months. Measurements of hip joint capsule thickness were taken on both MRI and ultrasound images for the same patients to analyze their consistency. Additionally, we measured the alpha angle, lateral center-edge angle, acetabular anteversion angle, and femoral anteversion angle of the patients' hip joints and analyzed their correlation with hip joint capsule thickness measure by ultrasound. RESULTS: A total of 307 patients were included in this study, with hip joint capsule thickness measured by MRI and ultrasound being 5.0 ± 1.2 mm and 5.0 ± 1.5 mm, respectively. The Bland-Altman analysis demonstrates good agreement or consistency. The paired t-test resulted in a p-value of 0.708, indicating no significant statistical difference between the two methods. The correlation analysis between acetabular anteversion angle and ultrasound-measured capsule thickness yielded a p-value of 0.043, indicating acetabular anteversion angle and capsular thickness may have negative correlation. CONCLUSIONS: The measurements of joint capsule thickness obtained through ultrasound and MRI showed good consistency, suggesting that ultrasound can be used in clinical practice as a replacement for MRI in measuring hip joint capsule thickness. There was a significant correlation between acetabular anteversion angle and hip joint capsule thickness, indicating potential for further research in this area.

Soil microorganisms facilitated the electrode-driven trichloroethene dechlorination to ethene by Dehalococcoides species in a bioelectrochemical system.

Bioelectrochemical dechlorination using organohalide-respiring bacteria (ORBs) is a promising technique for remediating contaminated groundwater. Generally, a longer enrichment period is required for selecting the ORB consortia to achieve bioelectrochemical dechlorination. However, the full dechloriantion is difficult to be achieved due to the absence of functional species (e.g. Dehalococcoides) in previously used enrich cultures. To overcome these challenges, bioelectrochemical dechlorination using a culture enriched with the pre-augmented Dehalococcoides was performed for the first time in this study. A two-chamber bioelectrochemical system (BES) inoculated with a pure Dehalococcoides culture and paddy soil with an applied voltage of -0.3 V (versus a standard hydrogen electrode) as the sole electron donor was used to achieve dechlorination. The ethene formation rate was 10-100 times higher than that in previous studies, indicating that inoculating the system with a pure Dehalococcoides culture and soil microorganisms gave effective full dechlorination performance. Microbial community analysis and bioelectrochemical analysis indicated that Desulfosporosinus species may have facilitated dechlorination through syntrophic interactions with Dehalococcoides. The results indicated that adding Dehalococcoides cells before operating a bioelectrochemical system is an effective way of achieving full dechlorination.

Anterior tibial subluxation measured under a modified protocol is positively correlated with posterior tibial slope: a comparative study of MRI measurement methods.

PURPOSE: Anatomic factors, such as posterior tibial slope (PTS) and anterior tibial subluxation (ATS) obtained by quantitative measurement, have been proposed as predictors for clinical outcomes of anterior cruciate ligament (ACL) reconstruction. However, the correlation between PTS and ATS is controversial, and the method for quantitative ATS measurement remains unsettled. This study aimed to identify the correlation between PTS and ATS in patients with injured and intact ACLs and compare the two ATS measuring protocols. METHODS: This study included 128 ACL-injured and 176 ACL-intact patients with no concomitant ligament injuries. PTS and ATS were measured on sagittal MRI. ATS was measured using two measuring protocols, including the modified protocol using the longitudinal tibial axis (axis protocol) and the established protocol using a line perpendicular to the tibial plateau (plateau protocol). Correlation analyses between PTS and ATS and between PTS and the difference in the ATS value measured under the two protocols (ATSdiff) were performed. The difference between the two ATS measuring protocols was further analyzed by trigonometric analysis. Intra- and interobserver reliability tests were performed for the axis protocol. RESULTS: Under the axis protocol, ATS was positively correlated with PTS in both the ACL-injured and ACL-intact groups (p < 0.001). Under the plateau protocol, no correlation was observed in the ACL-injured group. In the ACL-intact group, no correlation was observed for lateral ATS, and a negative correlation was observed for medial ATS (p = 0.001). ATSdiff was positively correlated with PTS (p < 0.001), indicating that the two protocols varied greatly in those with a steep PTS. Trigonometric analysis showed that a steep PTS influenced the measurement of ATS under the plateau protocol but not the axis protocol. Intra- and interobserver reliability tests showed good-to-excellent strength of reliability for the ATS measurement under the axis protocol. CONCLUSION: ATS measured under the axis protocol was positively correlated with PTS, indicating that a steep PTS was associated with a worse anatomic tibiofemoral relationship. The axis protocol for ATS measurement is a promising method for clinical use since it is not influenced by PTS and reflects the global position of the tibia. LEVEL OF EVIDENCE: III.

Endoscopic endoclip papilloplasty preserves sphincter of oddi function.

BACKGROUND: Endoscopic sphincterotomy (EST) can destroy sphincter of Oddi (SO) structure and function. The purpose of this study was to assess the feasibility of endoscopic endoclip papilloplasty (EEPP) in restoring SO function after EST. METHODS: Seven 26-week-old domestic pigs were divided into control and EEPP groups. Necropsy and haematoxylin-eosin staining plus anti-α-smooth muscle actin (α-SMA) staining of papilla and sphincter of Oddi manometry (SOM) were conducted in animals at three independent time points. RESULTS: EST and EEPP were safely performed in all 7 pigs without serious adverse events. For primary outcome, compared to the controls, EEPP generated smaller dilation and less inflammation. Fibrous repair of the papilla was observed at 24 weeks after EEPP. For secondary outcome, in the control group, SO basal pressure (17.25 ± 18.14 to 5.50 ± 0.71 mmHg), SO contraction amplitude (46.00 ± 19.20 to 34.50 ± 48.79 mmHg), peak (4.50 ± 4.04 to 1.50 ± 2.12) and frequency (3.05 ± 3.29 to 1.41 ± 2.19/min) were reduced after EST. Further reductions to almost 0 of these SOM parameters were observed 3 weeks later, including common bile duct pressure and SO contraction period. In contrast, in the EEPP group, these manometric data were recovered to pre-EST levels, including CBD pressure (11.5 ± 7.31 vs 11 ± 2.16 mmHg), SO pressure (17.50 ± 17.75 vs 18.20 ± 21.39 mmHg) and SO contraction amplitude (53.67 ± 21.54 vs 60.00 ± 36.08 mmHg). However, no significant differences were observed between control and EEPP groups by Student t test. CONCLUSIONS: In this porcine study, EEPP accelerated and improved papillary healing after EST, further preserved SO function.

Public perceived knowledge of, attitude toward, and use of genetic testing in urban China.

Because most research about laypeople and genetic testing (GT) has been conducted in other nations than China, we conducted a study in urban China (a) to determine the perceived knowledge of, attitude toward, and use of GT there; (b) to identify influencing factors associated with the public's perceived knowledge, attitudes, and use of GT; and (c) to explore the relationship among public knowledge of, attitude toward, and use of GT. Our data came from a community-based survey in urban Dalian of 868 individuals. We used generalized ordered logit and logit models to examine factors associated with perceived knowledge of, attitude toward, and use of GT. We found that 67% of community members knew about GT, that 45% had a positive opinion of GT, and that only 4% accessed GT. Older people were more likely to have less perceived knowledge of GT and less likely to have a negative attitude toward it; these relationships were especially stronger among those aged ≥60 years. We also found that socially disadvantaged people were more likely to have less perceived knowledge of GT and more likely to have a negative opinion of it. Having a greater level of perceived knowledge was significantly correlated with increased odds of having a more positive or neutral attitude toward GT and of being more likely to access GT. Our findings may help policy makers design effective action plans and regulations regarding GT and genetic counseling services for laypersons in China.

[Current status of organophosphorus pesticide residues in root and rhizome medicinal materials and research progress of rapid detection methods].

The medicinal plants with roots and rhizomes as the medicinal parts account for about 1/3 of Chinese medicinal herbs. Root and rhizome medicinal materials are widely used in clinical practice, whereas their wild resource reserves are insufficient to meet the market demand. With the expansion of planting areas, the formation of large-scale production areas, and the increase in planting years, diseases and insect pests of these medicinal plants, which are diverse and have broad transmission routes, strong concealment, and heavy damage, have become more and more serious. The prevention and control of these diseases and insect pests is characterized by multiple ways of pesticide application, large consumption of pesticides, susceptibility to soil barrier, difficulty in the control, and unstable control efficiency. Organophosphorus pesticides(OPPs) are widely used in the cultivation of Chinese medicinal plants because of their diverse varieties, broad-spectrum, good efficacy, and low residues, and have a positive effect on the yield and quality of Chinese medicinal materials. However, the abuse of OPPs not only increases the planting cost, but also affects the quality and safety of Chinese medicinal plants, the safety of clinical use of Chinese medicine, and the ecological safety of production areas. This paper reviewed the research and development progress of OPPs, the registration status of OPPs used in root and rhizome medicinal materials, residue limit standards, residue status, and rapid detection technology progress of OPPs. This review aims to provide research ideas and references for standardizing the use of OPPs in root and rhizome medicinal materials, reducing OPP residues, and establishing a fast, efficient, accurate, and reliable method for the detection of OPP residues in Chinese herbal medicine.

Experimental research on a Raman-based distributed temperature sensor assisted by PCA for locating the temperature abnormal event of nuclear waste drums.

Aimed at locating the temperature abnormal event of nuclear waste drums in a nuclear waste temporary storage repository by a Raman-based distributed temperature sensor, a principal component analysis (PCA)-based method for application is proposed. The effectiveness of the proposed method is verified in the physical simulation device of the nuclear waste drums. First, some samples of the temperature abnormal event with known location are taken as the reference samples, and their features are extracted by PCA. Then, the features of the test sample data to be located are also extracted by PCA. The Euclidean distance is used to measure the similarity between the features of the test sample and the feature of each reference sample. Finally, we find the reference sample that is most similar to a test sample, the location of which is considered the location of the temperature anomaly event for the test sample. The experimental results show that the proposed method can accurately locate the temperature abnormal event of the nuclear waste drums, and the accuracy rate can reach 96%. The method that is proposed in this paper can reliably locate the temperature abnormal event generated by the nuclear waste temporary storage repository induced by external factors such as landslides or earthquakes, and provide technical support for nuclear safety.

Serum microRNA as potential biomarker to detect breast atypical hyperplasia and early-stage breast cancer.

AIM: The present study aimed to identify microRNA (miRNA) that can be used for not only detecting early-stage breast cancer (BC) but also diagnosing atypical hyperplasia (AH). MATERIALS & METHODS: RT-qPCR detected the expression levels of miRNAs and receiver operating characteristic curves were constructed to evaluate sensitivity and specificity of the assay. RESULTS: miR-24 and miR-103a were expressed in an upward trend in serum of benign proliferative tumor subjects, while they were downregulated significantly in serum of AH (p < 0.005) and early-stage BC subjects (p < 0.005) with high sensitivity and specificity as compared with controls. Bioinformatics analysis also revealed the potential molecular mechanism through which miR-24 and miR-103a regulate tumorigenesis in BC. CONCLUSION: miR-24 and miR-103a were valuable biomarkers for distinguishing AH and early-stage BC from healthy individuals/benign proliferative tumor patients.

Synergistic Antitumor Effect of Sorafenib in Combination with ATM Inhibitor in Hepatocellular Carcinoma Cells.

Background: Currently, sorafenib is the only systemic chemotherapy drug for advanced stage Hepatocellular carcinoma (HCC). However, emerging data from some clinical HCC patients indicate that sorafenib alone has only moderate antitumor efficacy, and could not inhibit disease metastasis and progression. KU-55933 is a specific ATM inhibitor, which has pro-apoptotic effect on tumor cells. In this study, we analyzed the synergistic effect of sorafenib and KU-55933 on the proliferation of HCC cell lines. Methods: Three HCC cell lines were treated with sorafenib and KU-55933 alone or combination in vitro to investigate inhibitory effect by MTT and wound healing assay. Epithelial to mesenchymal transition (EMT) phenotype change was investigated after sorafenib and KU-55933 treatment by microscopy. Akt signaling pathway proteins including p-Akt, p-mTOR and p-p70S6K were examined by western blot. In addition, cleaved PARP and autophage-related proteins LC3A/B were detected by western blot. Results: KU-55933 can enhance the effect of sorafenib in inhibiting cell proliferation and migration, overcoming EMT, inducing cell apoptosis via inactivating Akt signaling pathway and inducing autophage. The combination treatment with sorafenib and KU-55933 resulted in a strong synergistic effect in vitro. Conclusion: Our results demonstrate that sorafenib combined with KU-55933 treatment does effectively inhibit proliferation of HCC cell lines synergistically. These data suggests that KU-55933 may be a promising chemosensitizer to sorafenib in the treatment of HCC.

Memory-Enabled Quantum-Dot Light-Emitting Diodes.

Quantum-dot light-emitting diodes (QLEDs) with memory capability can provide multifunctional integration properties in on-chip and intelligent electronic applications. Herein, memory properties are achieved by inserting a tungsten oxide (WOx) film between the ZnO electron-transporting layer and cathode. Pentavalent tungsten ions (W5+) in this nonstoichiometric WOx film can be oxidized to W6+ by storing holes, inducing significant electrons in the adjacent ZnO layer. Hole storage in the WOx layer suppresses electron injection into the quantum dot emissive layer, hence reducing electroluminescence intensity on the onset stage of the QLEDs. This operation-history correlation for the electroluminescence intensity means a memory behavior for the QLEDs. Furthermore, the power efficiency of the devices is greatly improved after inserting the WOx layer due to electrical field-dependent self-adaptive electron injection into the quantum dots (QDs). We anticipate this type of QLEDs have potential applications in on-chip integration applications, such as the optical computing field and storage.

Protect the oceans from Japan's radioisotope dumping.

•Dumping of Fukushima's radioactive wastewater raises marine food web concern.•Tritium seems to be the most problematic compound.•Long-lived radioisotopes Biomagnify up to 50,000 folds in marine fish species.•This threatens fragile deep-sea ecosystems requiring immediate action.•Empowered Routine monitoring is crucial to maintain planetary health.

Physical Model of Inclusions Removal at Static Steel-Slag Interface.

Inclusions are one of the important factors affecting the cleanliness of molten steel. The current optimization of inclusion removal methods mainly focuses on promoting inclusions to float to the slag-steel interface so that the inclusions can be absorbed and removed by the refining slag. However, the research on the floating removal of inclusions cannot be carried out directly in the ladle, so methods such as mathematical models and physical models were developed. This article uses silicone oil to simulate the slag layer; polypropylene particles; and aluminum oxide particles to simulate inclusions to establish a water model experiment. By changing the viscosity of silicone oil and the diameter of particles, the factors affecting the movement of inclusions at the slag-steel interface were explored. Based on the water model, a mathematical model of the floating behavior of inclusions at the slag-steel interface was constructed, and parameters such as particle diameter and interfacial tension in the water model experiment were studied by the mathematical model for calculation. Both the mathematical model and the water model experimental results show that after the viscosity of silicone oil increases from 0.048 Pa·s to 0.096 Pa·s, the dimensionless displacement and terminal velocity of the particles decreases. When the diameter of the same particle increases, the dimensionless displacement and terminal velocity increases. The dimensionless displacement of polypropylene particles of the same diameter is larger than that of aluminum oxide particles, and the terminal velocity is smaller than that of aluminum oxide particles. This is attributed to the better overall three-phase wettability of polypropylene particle. When the liquid level increases, the dimensionless displacement and terminal velocity of particles under the same conditions show only slight differences (less than 10%).

Polyphasic Characterization of Geotalea uranireducens NIT-SL11 Newly Isolated from a Complex of Sewage Sludge and Microbially Reduced Graphene Oxide.

Graphene oxide (GO), a chemically oxidized sheet of graphite, has been used as a conductive carbon carrier of microbes to boost various bioelectrochemical reactions. However, the types of microbes that can reduce GO have rarely been investigated. In this study, a strain of GO-reducing bacteria, named NIT-SL11, which was obtained from a hydrogel of microbially reduced GO and anaerobic sludge that converts sewage to electricity, was phylogenically identified as a novel strain of Geotalea uraniireducens. Considering the current lack of information on the electrogenic ability of the bacterium and its physicochemical and chemotaxonomic characteristics, the polyphasic characterization of the Geotalea uraniireducens strain NIT-SL11 was performed. NIT-SL11 utilized various organic acids, such as lactate, benzoate, and formate, as electron donors and exhibited respiration using GO, electrodes, fumarate, and malate. The strain contained C16:1ω7c and C16:0 as the major fatty acids and MK-8 and 9 as the major respiratory quinones. The complete genome of NIT-SL11 was 4.7 Mbp in size with a G+C content of 60.9%, and it encoded 80 putative c-type cytochromes and 23 type IV pili-related proteins. The possible extracellular electron transfer (EET) pathways of the strain were the porin-cytochrome (Pcc) EET pathway and type IV pili-based pathway.

Soil organic matter and nutrient availability affect the applicability of low-carbon energy source in Dehalococcoides-augmented soil.

Dehalococcoides is a functional microorganism that completely dechlorinates trichloroethene (TCE). Augmentation with pure Dehalococcoides is important for reducing environmental disturbances that accompany bioaugmentation. However, the applicability of Dehalococcoides-bioaugmentation to contaminated soils is unclear. In this study, seven low-carbon energy sources (methanol, formate, acetate, ethanol, lactate, citrate, and benzoate) were used as electron donors for Dehalococcides to evaluate its applicability in remediating TCE-contaminated soils. Soil microcosms supplemented with ethanol, formate, or lactate showed relatively high dechlorination activity within 111-180 days. The functional gene profiles predicted by PICRUSt2 from 16 S rRNA gene sequences were similar in the proportions of dehydrogenases, which initiate electron donor oxidation, in all soils and did not seem to reflect Dehalococcoides-bioaugmentation applicability. Soils with higher organic matter content (>3.2%; dry weight base) and protein concentration (>1.6 µg/mL) supported complete dechlorination. These results suggest that organic matter and nutrient availability mainly affect successful TCE dechlorination in Dehalococcoides-augmented soils. The study offers significant experimental support for comprehending the suitability of low-carbon energy sources in successful bioaugmentation, aiming to mitigate environmental disturbances associated with the process.

Dehalococcoides mccartyi strain NIT01 grows more stably in vessels made of pure titanium rather than the stainless alloy SUS304.

Advances in many isolation studies have revealed that pure Dehalococcoides grow stably, although the large-scale pure cultivation of Dehalococcoides has yet to be established. In this study, 7 L-culturing of Dehalococcoides mccartyi strain NIT01 was first performed using vessels made of glass and stainless alloy SUS304. All batches cultured in the glass vessel successfully dechlorinated >95% of 1 mM trichloroethene (TCE) to ethene (ETH), whereas only 5 out of 13 batches cultured in the SUS304 vessel did the same. The difference in dechlorination efficiency suggested the possible inhibition of dechlorination by SUS304. Also, the strain NIT01 showed long delays in dechlorination with pieces of SUS316, steel, and a repeatedly used SUS304, but not with titanium. The repeatedly used SUS304 cracked and increased the Fe2+ concentration to ≥76 µM. Dechlorination by this strain was also inhibited with ≥1000 µM Fe2+ and ≥23 µM Cr3+ but not with ≤100 µM Ni2+ , suggesting that Cr3+ eluted from solid stainless alloys inhibited the dechlorination. Culturing in a titanium vessel instead of a stainless alloy showed the complete dechlorination of 1 mM TCE within 12-28 days with a growth yield of 2.7 × 107 cells/µmol-released Cl- , even after repeating use of the vessels six times.

Functional polymer brushes for anti-microplastic pollution.

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Outcomes of laparoscopic pancreaticoduodenectomy using a modified technique：346 cases from a single center.

PURPOSE: To study the outcomes of laparoscopic pancreaticoduodenectomy (LPD) using a modified technique. METHODS: Our center used priority approach of uncinate process and artery in the pancreatectomy and duct to mucosa pancreaticojejunostomy with a single stitch in the pancreaticojejunostomy. Herein, we retrospectively reviewed 346 cases of LPD using modified techniques. Basic characteristics, preoperative outcomes, factors associated with unfavorable postoperative outcome, and mortality of patients undergoing LPD were collected and analyzed. RESULTS: The average operative time was 259.31 (35-425) min. The mean duration of pancreaticojejunostomy anastomosis was 31.97 (16-90) min. The mean intraoperative blood loss was 101.76 (0-1200) ml by estimation. Postoperative complications included 14 cases (4.1%) of bile leakage, 9 cases (2.6%) of delayed gastric emptying, 26 cases (7.5%) of postoperative bleeding, 34 cases (9.9%) of organ space infection, 17 cases (4.9%) of pulmonary infection, and 50 cases (14.5%) of POPF. Three factors including postoperative bleeding (OR = 3.502; P = 0.033), positive lymph node (OR = 3.296; P < 0.001), and postoperative chemotherapy (OR = 0.241; P = 0.008) were significantly associated with death of LPD. CONCLUSIONS: The modified technique for LPD presents safety and reliability. Postoperative bleeding and positive lymph node may be associated with worse overall survival, and postoperative chemotherapy may be associated with better overall survival.

Glutathione-modified graphene quantum dots as fluorescent probes for detecting organophosphorus pesticide residues in Radix Angelica Sinensis.

A novel fluorescent sensor was developed in this study based on glutathione-functionalized graphene quantum dots (GQDs@GSH) to detect organophosphorus pesticide residues in Radix Angelica Sinensis. GQDs@GSH was synthesized by a one-step pyrolysis method with a fluorescence quantum yield as high as 33.9% and its structure was characterized by transmission electron microscopy and X-ray photoelectron spectroscopy. GQDs@GSH exhibited excellent fluorescence property showing strong blue fluorescence under UV irradiation. The fluorescence of GQDs@GSH could be quenched by Fe3+ by electron transfer and the quenched fluorescence could be recovered due to the strong chelating and reducing ability of phytic acid (PA). Under the catalyzation of acetylcholinesterase (AChE) and choline oxidase (ChOx), acetylcholine (ACh) could be decomposed to H2O2, which could further oxidize Fe2+ to Fe3+ thus quenching the fluorescence of GQDs@GSH once again. Coumaphos, a kind of organophosphorus pesticide, could inhibit AChE activity, thus making the quenched fluorescence turn on again. Several parameters influencing the fluorescence response such as Fe3+, PA, ACh and coumaphos concentration, pH value and reaction time were optimized. Based on such a fluorescence "off-on-off-on" ngkmechanism, GQDs@GSH was successfully applied to the detection of coumaphos in Radix Angelica Sinensis. A good linear relationship between the fluorescence intensity and coumaphos concentration was obtained in the range of 0.1-10.0 µmol·L-1. By a standard addition method, the recoveries were measured to be 101.44-117.90% with RSDs lower than 1.98%. The biosensor system is simple, sensitive and accurate. It has a good application prospect in the detection of organophosphorus pesticide residues in traditional Chinese medicine and agricultural products, and also expanded the application scope for glutathione as a highly selective biological molecule.

Chronic ACL-injured patients show increased medial and global anterior tibial subluxation measured on 1-year postoperative MR images after primary single-bundle ACL reconstruction.

BACKGROUND: The association between chronic anterior cruciate ligament (ACL) injury and inferior postoperative outcomes following ACL reconstruction (ACLR) has been highlighted in the literature. However, the inclusion of postoperative radiological assessments in previous studies has been limited. The aim of this study is to investigate whether chronic ACL injury is associated with an inferior tibiofemoral position measured on magnetic resonance (MR) images after primary ACLR. METHODS: A total of 62 patients that underwent primary ACLR were included in this study based on the time from injury to surgery, namely the acute ACL-injured group (within 6 weeks) and the chronic ACL-injured group (more than 1 year) and were matched 1:1 according to sex, age (± 2 years), and time from surgery to follow-up (± 3 months). Patient demographics, surgical records and follow-up data were retrieved and analyzed. The altered tibiofemoral position was measured quantitatively on preoperative and at least 1-year postoperative MR images and compared between the two groups, including the lateral, medial and global anterior tibial subluxation (LATS, MATS and GATS) and internal rotational tibial subluxation (IRTS). RESULTS: No significant differences in preoperative LATS, MATS, GATS or IRTS were identified between the acute and chronic ACL-injured groups. The chronic ACL-injured patients showed significantly increased postoperative MATS (p = 0.001) and GATS (p = 0.012), while no significant difference was identified in postoperative LATS or IRTS. Multivariate linear regression analyses showed that chronic ACL injury resulted in an estimated increase of 2.0 mm in postoperative MATS (p = 0.012) and 1.9 mm in postoperative GATS (p = 0.040). A significant improvement in postoperative LATS was observed in the acute ACL-injured group (p = 0.044) compared to preoperative LATS, while no improvements in these MRI measurements were observed in the chronic ACL-injured group. CONCLUSION: Chronic ACL-injured patients showed increased MATS and GATS measured on 1-year postoperative MR images after primary single-bundle ACL reconstruction, while no difference was identified in rotational tibiofemoral position. The acute ACL-injured group demonstrated a significant improvement in postoperative LATS, whereas no improvements were observed in the chronic ACL-injured group. Level of evidence Level III.