Pulsed lavage is associated with better quality of bone-cement-implant interface in knee arthroplasties (TKA/UKA) compared to syringe lavage in vitro; however, clinical data are missing: A systematic review.

Purpose: The purpose of this systematic review is to analyse the available literature to ascertain the optimal method of bone preparation to improve the quality of bone-cement-implant interface with either pulsed lavage or syringe lavage in both total knee arthroplasty (TKA) and unicompartmental knee arthroplasty (UKA). Methods: A comprehensive search was conducted across MEDLINE, Scopus and Embase databases until July 2023. Both inclusion and exclusion criteria were clearly stated and used to identify all the published studies. Subsequent screening throughout the title, abstract and full text was made, followed by complete critical appraisal and data extraction. This sequential process was performed by two reviewers independently and summarised following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines). A quality assessment of the systematic review was performed according to the Quality Appraisal for Cadaveric Studies scale (QUACS), reaching a quality level ranging from 69% to 85%. Results: A total of 10 articles, out of 47, nine biomechanical cadaveric studies and one human clinical study were analysed. A total of 196 UKA tibial components, 74 patellar components, 36 TKA tibial components and 24 UKA femoral components were retrieved, and a high level of heterogeneity resulted overall. The pulsed lavage group showed better cement penetration and higher pull-out force than the syringe lavage group; a higher interface temperature was also found in the pulsed lavage group. No differences were found regarding tension ligament forces between the groups. Conclusion: Our systematic review suggests that pulsed lavage is superior to syringe lavage in terms of the quality of bone-cement-implant interface in knee arthroplasties (TKA/UKA). However, translation of these results from cadaveric studies to individual clinical settings may be hazardous; therefore, clinical in vivo prospective studies are highly needed. PROSPERO CRD: PROSPERO CRD number CRD42023432399. Level of Evidence: Level III.

Stereotactic body radiotherapy for centrally located inoperable early-stage NSCLC: EORTC 22113-08113 LungTech phase II trial results.

BACKGROUND: The international EORTC phase II single-arm LungTech trial 22113-08113 assessed safety and efficacy of stereotactic body radiotherapy (SBRT) in patients with centrally located early-stage non-small cell lung cancer (NSCLC). PATIENTS AND METHODS: Patients with inoperable non-metastatic central NSCLC (T1-T3 N0 M0, ≤7cm) were included. After prospective central imaging review and radiation therapy quality assurance (RTQA) for any eligible patient, SBRT (8x7.5 Gy, ICRU 83) was delivered. The primary endpoint was freedom from local progression probability at three years after start of SBRT. RESULTS: The trial was closed earlier due to poor accrual related to repeated safety-related pauses in recruitment. Between 08/2015 and 12/2017, 39 patients from 6 European countries were included and 31 were treated per protocol and analyzed. Patients were mainly male (58%) with a median age of 75 years. Baseline comorbidities were mainly respiratory (68%) and cardiac (48%). Median tumor size was 2.6 cm (range, 1.2-5.5) and most cancers were T1 (51.6%) or T2a (38.7%) N0 M0 and of squamous cell origin (48.4%). Median follow-up was 3.6 years. The 3-year freedom from local progression and overall survival rates were 81.5% (90% CI: 62.7-91.4%) and 61.1% (90%CI: 44.1-74.4%), respectively. Cumulative incidence rates of local, regional and distant progression at 3 years were 6.7% (90% CI: 1.6-17.1%), 3.3% (90% CI: 0.4 - 12.4%) and 29.8% (90% CI: 16.8 - 44.1%), respectively. SBRT-related acute and late AEs ≥ G3 were reported in 6.5% (n=2, including one G5 pneumonitis in a patient with prior interstitial lung disease) and 19.4 % (n=6, including one lethal hemoptysis after a lung biopsy in a patient receiving anticoagulants), respectively. CONCLUSION: The LungTech trial suggests that SBRT with 8×7.5Gy for central lung tumors in inoperable patients is associated with acceptable local control rates. However, late severe adverse events may occur after completion of treatment. This SBRT regimen is a viable treatment option after thorough risk-benefit discussion with patients. To minimize potentially fatal toxicity, careful management of dose constraints and post-SBRT interventions is crucial.

A slight degree of osteoarthritis appears to be present after anterior cruciate ligament reconstruction compared with contralateral healthy knees at a minimum of 20 years: A systematic review of the literature.

Purpose: The aim of the present systematic review was to quantitatively synthesize the best literature evidence regarding osteoarthritis developing after anterior cruciate ligament reconstruction (ACLR), including only studies with a follow-up duration of at least 20 years. Material and Methods: A systematic review was conducted based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines on four electronic databases (PubMed, Scopus, EMBASE and Cochrane Library). The outcome measures extracted from the studies were failure rate, subsequent knee surgery on the same knee, radiographic development of osteoarthritis measured with Kellgren-Lawrence, International Knee Documentation Committee (IKDC) radiographic score and Ahlbäck classification. The health of both the ACLR knee and the contralateral knee was compared. Results: A total of 1552 patients were included in the study, of which 1290 (83.11%) were operated on using a patellar tendon graft, 190 (12.24%) with hamstrings, 27 (1.73%) with an iliotibial band and 45 (2.89%) with patellar tendon plus a ligament augmentation device (LAD). The mean age at the time of surgery was 25.18 ± 1.91 years, and the mean follow-up time was 23.34 ± 2.56 years. Analysing IDKC Score at final follow-up, ACLR Group showed a higher degree of OA compared with contralateral healthy knee (p < 0.01), but only 33.2% (324/976) of the patients showed a moderate to severe degree (Grade C or D) of osteoarthritis, while for Kellgren-Lawrence, ACLR Group showed a higher degree of OA compared with contralateral healthy knee (p < 0.01), but only 28.9% (196/678) of the patients showed a moderate to severe degree (Grade III or IV) of osteoarthritis. In total, 1552 patients were registered, 155 reruptures (9.98%) and a total of 300 (19.3%) new surgeries, of which 228 meniscectomy (14.69%), 21 (1.35%) knee arthroplasty and 17 (1.09%) hardware removal were recorded. Conclusions: ACL reconstruction appears to result in mild osteoarthritis in the long term in most of the patients and only less than 33.2% develop a moderate to severe degree of knee OA according to IKDC radiographic score. A slight degree of osteoarthritis appears to be present in ACLR knees compared with contralateral healthy knees. Level of Evidence: Level IV.

Robotic-assisted total knee arthroplasty is not associated with improved accuracy in implant position and alignment compared to conventional instrumentation in the execution of a preoperative digital plan.

Purpose: The primary objective of the present study was to evaluate if robotic-assisted total knee arthroplasty (RO-TKA) results in improved accuracy compared to conventional TKA (CO-TKA) with respect to alignment and component positioning executing a preoperative digital plan. The secondary objective was to compare patient-reported outcome measures (PROMs) between the two groups at 6 months of follow-up (FU). Methods: Patients who underwent primary TKA using the concept of constitutional alignment were identified from the database. Each patient underwent preoperative digital planning as well as postoperative evaluation of the preoperative plan (alignment and component position) using mediCAD® software (Hectec GmbH). Two groups were formed: (i) The RO-TKA group (n = 30) consisted of patients who underwent TKA with a robotic surgical system (ROSA®, Zimmer Biomet) and (ii) the CO-TKA group (n = 67) consisted of patients who underwent TKA with conventional instrumentation. To assess accuracy, all qualitative variables were analysed using the χ 2 test. Tegner activity scale, Oxford Knee Score and visual analogue scale were assessed preop and at 6-month FU. To assess differences between the two groups, a 2 × 2 repeated measures analysis of variance was performed. Results: There was no significant (p > 0.05) difference in the accuracy of alignment as well as tibial and femoral component position between the two groups. At the 6-month FU, there was no significant (p > 0.05) difference in PROMs between the two groups. Conclusion: While robotic TKA may have some potential advantages, no significant difference was found between robotic and conventional TKA with respect to limb alignment, clinical outcomes and component positioning. Level of Evidence: Level III.

The "Golden Age" of quadriceps tendon grafts for the anterior cruciate ligament: a bibliometric analysis.

IMPORTANCE: Bibliometric research is a statistical analysis of publications to measure the scientific output in a specific field in order to highlight medical developments or knowledge gaps and to direct future scientific research. The quantity of orthopedic papers on the internet is astounding and is steadily growing as a result of recent advancements in technology and medicine. This is why choosing the right information is essential. AIM: The purpose of this study was to analyze the current literature for trends in publications regarding quadriceps tendon (QT) grafting of the anterior cruciate ligament (ACL). EVIDENCE REVIEW: PubMed was searched on August 28, 2023. References were collected from PubMed, and trends were analyzed using this information. This search retrieved 405 articles regarding human and animal studies. We analyzed the top 10 authors and journals in terms of publication numbers, citation numbers, and citations per year. The PubMed-by-year feature was used to compare the number of publications regarding ACL reconstruction by quadriceps grafting with all publications in PubMed. FINDINGS: The number of yearly publications averaged 10 or less up to 2018, starting from 1982 when the first paper on the QT was published. However, the number of publications increased from 2018. While the total number of publications on this topic was 405, 260 were published from 2018 alone. The number of citations was 8262 in total overall years. It is expected that the last five years' publications, especially those for the last year, will be low in number, as it takes time for citations to accrue. The journal Arthroscopy published the most articles on this topic, with 57 papers and 1884 citations, followed by the American Journal of Sports Medicine, with 39 articles and 1576 citations. The top three journals on this topic were Arthroscopy, AmericanJournalofSportsMedicine, and KneeSurgery, SportsTraumatology, Arthroscopy. The most published author was Musahl V (with 24 articles), and the most cited author was Xerogeanes JW (with 570 citations). CONCLUSIONS AND RELEVANCE: Global trend analysis suggests that research on anterior cruciate ligament reconstruction with the quadriceps has significantly increased in the last 5 years and that the number of papers on this topic is increasing steadily. We found that the publications and citations are exhibiting a rising trend, Arthroscopy is the most impactful journal, and Musahl V is the most impactful author on the topic. Xerogeanes JW is the author with the most citations on the topic. The promising clinical results of anterior cruciate ligament reconstruction with the QT have attracted the most research interest. LEVEL OF EVIDENCE: Level IV.

Primary Versus Revision ACL Reconstruction Using Quadriceps Autograft: A Matched-Control Cohort Study.

Background: The incidence of anterior cruciate ligament (ACL) reconstruction is increasing, and quadriceps tendon (QT) autograft is gaining popularity for both primary and revision ACL reconstruction. Purpose: To evaluate the differences in the patient-reported functional outcomes, concomitant injuries, and graft failure in primary versus revision ACL surgery using QT autograft. Study Design: Cohort study; Level of evidence, 3. Methods: A total of 376 patients with primary ACL reconstruction and 138 patients with revision ACL reconstruction were retrospectively retrieved from a prospectively collected ACL registry. A minimally invasive technique was used for QT autograft harvesting. The surgical procedure and rehabilitation protocol were identical in both groups. To maintain a homogeneous cohort for the study, the groups were matched by age, sex, and preinjury outcome scores (Lysholm knee score, Tegner activity level, and visual analog scale [VAS] for pain). Initial baseline assessments of outcome scores were compared with scores collected at the 2-year postoperative mark. Results: The mean age of the primary group and revision group was 32.9 ± 10.2 years (range, 18-55 years) and 32.3 ± 9.9 years (range, 19-55 years) respectively. Significant preinjury to postoperative improvements were noted in Lysholm (88.2 ± 16.4 vs 83.5 ± 15.0; P = .007) and VAS pain (0.9 ± 1.3 vs 1.5 ± 1.6; P = .001) scores after primary ACL reconstruction compared with revision reconstruction. However, no significant difference was found in Tegner activity level (6.7 ± 1.8 vs 5.9 ± 1.8; P > .430). Primary ACL injury was associated with significantly higher concomitant medial collateral ligament injuries (P = .019), while the revision group was associated with significantly higher concomitant cartilage (P = .001) and meniscal (P = .003) injuries. A significantly higher graft failure rate was noted in the revision group compared with the primary ACL reconstruction group (13.0% vs 5.6%; P = .005). Conclusion: Both primary and revision ACL reconstruction with QT autograft had acceptable functional outcomes. The primary group had better outcomes than the revision group, possibly due to the lower prevalence of meniscal and cartilage injuries in the primary group compared with the revision group. The revision group was associated with higher graft failure than the primary group. QT autograft is a viable graft choice for both primary and revision ACL reconstruction.

Quality of YouTube Videos Regarding Anterior Cruciate Ligament Reconstruction Using Quadriceps Tendon Autograft Is Unsatisfactory.

PURPOSE: To assess the validity and informational value of teaching material regarding anterior cruciate ligament reconstruction (ACLR) using quadriceps tendon (QT) autograft provided on the YouTube video platform. METHODS: An extensive systematic search of the YouTube video platform was performed, and all videos that met the criteria were included in the analysis. The analysis of the video content was performed using the DISCERN instrument, Journal of American Medical Association (JAMA) benchmark criteria, and Global Quality Score (GQS). The duration of the videos, the date of publication, and the number of likes and views were recorded. Furthermore, videos were categorized based on the source (physicians, companies, patients), the subject (surgical technique, patient experience and overview [overview videos were videos in which multiple aspects were analyzed]), and the type of content (educational or subjective patient experience). RESULTS: A total of 88 videos were included in the analysis. Seventy-one (80.7%) videos were published by physicians, 15 (17.0%) by patients, and 2 (2.3%) by companies. The majority of the videos described various surgical techniques (59%-67.0%), 80.7% of the videos (72%-81.8%) had an educational nature, and the remaining 18.2% described patient experiences. The mean length of the videos was 8.21 ± 7.88 minutes. The mean number of views was 3,988.51 ± 9,792.98 (range 9-56,047), whereas the mean numbers of comments and likes were 30.07 ± 70.07 (range 0-493) and 4.48 ± 14.22 (range 0-82), respectively. The mean DISCERN score, JAMA score, and GQS were 27.43 ±11.56 (95% confidence interval [CI] 25.01-29.85; range: 17-68), 1.22 ± 0.85 (95% CI 1.04-1.40; range 0-3), and 1.82 ± 0.93 (95% CI 1.63-2.01; range 1-4), respectively. For all scores, videos published by physicians had greater quality (DISCERN score, JAMA score, and GQS) (P < .05). Among all of the analyzed videos, overview videos were of the highest quality (P < .05). CONCLUSIONS: YouTube is a fast and open-access source of mass information. The overall quality of the videos on ACLR performed using QT autograft was unsatisfactory, demonstrating low educational quality and reliability. Currently, YouTube cannot be recommended as a reliable source of information on ACLR with the QT.

Increased Intra-Articular Internal Tibial Rotation Is Associated With Unstable Medial Meniscus Ramp Lesions in ACL-Injured Athletes: An MRI Matched-Pair Comparative Study.

Purpose: To analyze internal tibial rotation through magnetic resonance imaging (MRI) of patients with anterior cruciate ligament (ACL) injuries with and without an unstable medial meniscal ramp lesion (MMRL). Methods: Retrospective analysis of prospectively data was performed to include all consecutive patients who underwent primary ACL reconstruction (ACLR) between January 2022 and June 2022. Two groups, ACLR + unstable MMRL and ACLR without MMRL, were constituted. Propensity score matching analysis was used to limit selection bias. The angle between surgical epicondylar axes (SEAs) and the tangent line of the posterior tibial condyles (PTCs) was measured to analyze the rotational alignment between distal femur and proximal tibia. MMRLs were defined unstable if they were ≥1 cm, if the lesions extend beyond the lower pole of the femoral condyle, and/or if there was displacement into the medial compartment by anterior probing. Results: Twenty-eight propensity-matched pairs were included. The ACLR + unstable MMRL presented a significantly greater internal rotation of the tibia compared to ACLR without MMRL (P < .001). An internal tibial rotation was associated with unstable ramp lesions in ACL-injured patients (odds ratio [OR], 0.36; 95% CI, 0.25-0.41; P < .0001). If SEA-PTC was 0°, the sensitivity and specificity of the SEA-PTC angle to detect unstable MMRL were respectively 100% (95% CI, 85%-100%) and 18% (95% CI, 8%-36%). Otherwise, if SEA-PTC angle was -10°, the sensitivity and specificity of the SEA-PTC angle to detect unstable MMRL were respectively 43% (95% CI, 27%-61%) and 96% (95% CI, 81%-100%). Bone edema of the posterior medial tibial plateau was significantly associated with unstable ramp lesions (OR, 1.58; 95% CI, 1.21-2.06; P = .029). Conclusions: Unstable MMRL concomitant to an ACL rupture was associated with an increased tibial internal rotation. Level of Evidence: Level III, retrospective comparative trial.

Medial Patellofemoral Ligament Reconstruction Using Pedicled Quadriceps Tendon Autograft Yields Similar Clinical and Patient-Reported Outcomes but Less Donor-Site Morbidity Compared With Gracilis Tendon Autograft.

PURPOSE: To compare clinical and patient-reported outcome measures (PROMs) in patients with recurrent patellar dislocation after medial patellofemoral ligament (MPFL) reconstruction using either a gracilis tendon (GT) or quadriceps tendon autograft (QT). METHODS: All MPFL reconstruction performed between 2017 and 2019 were reviewed retrospectively. Only patients with isolated MPFL reconstruction, without any major patellofemoral risk factors and a minimum follow-up of 24 months, were included in the study. Patients were matched with respect to sex, age, and body mass index. All patients were evaluated clinically and using PROMs. RESULTS: A total of 64 patients with an average follow up of 28.7 ± 7.5 months were included in this study. The mean Kujala score (GT: 84.8 ± 12.9, QT: 88.9 ± 10.1), Lysholm score (GT: 89.4 ± 10.2, QT: 88.4 ± 5.0), and visual analog scale score for pain (GT: 1.9 ± 1.8, QT: 1.1 ± 1.3) did not significantly differ between both groups. Tegner activity level was significantly greater (P = .027) in the QT group (5.5 ± 1.9) compared with the GT group (4.6 ± 1.8), but within the minimal clinically important differences. Occasional patellar instability events, but no recurrent dislocation, were reported in 12.5% in the GT group and 6.3% in the QT group (P = .39). Of all patients, 90.6% in the QT and 68.8% in the HT group exceeded the PASS for the Kujala score (P = .06). Significantly more patients (59.4%) treated with GT reported donor-site morbidity in the form of sensitivity deficit at the lower leg compared with those treated with QT (3.1%, P = .001). CONCLUSIONS: GT and QT MPFL reconstruction have comparable PROMs and patellar redislocation rates 2 years' postoperatively. Significantly more patients treated with GT reported lower-leg sensitivity deficit compared with those treated with QT. LEVEL OF EVIDENCE: Level III, retrospective case-control study.

Artificial Intelligence-Based Emphysema Quantification in Routine Chest Computed Tomography: Correlation With Spirometry and Visual Emphysema Grading.

OBJECTIVE: The aim of the study is to assess the correlation between artificial intelligence (AI)-based low attenuation volume percentage (LAV%) with forced expiratory volume in the first second to forced vital capacity (FEV1/FVC) and visual emphysema grades in routine chest computed tomography (CT). Furthermore, optimal LAV% cutoff values for predicting a FEV1/FVC < 70% or moderate to more extensive visual emphysema grades were calculated. METHODS: In a retrospective study of 298 consecutive patients who underwent routine chest CT and spirometry examinations, LAV% was quantified using an AI-based software with a threshold < -950 HU. The FEV1/FVC was derived from spirometry, with FEV1/FVC < 70% indicating airway obstruction. The mean time interval of CT from spirometry was 3.87 ± 4.78 days. Severity of emphysema was visually graded by an experienced chest radiologist using an established 5-grade ordinal scale (Fleischner Society classification system). Spearman correlation coefficient between LAV% and FEV1/FVC was calculated. Receiver operating characteristic determined the optimal LAV% cutoff values for predicting a FEV1/FVC < 70% or a visual emphysema grade of moderate or higher (Fleischner grade 3-5). RESULTS: Significant correlation between LAV% and FEV1/FVC was found (ϱ = -0.477, P < 0.001). Increasing LAV% corresponded to higher visual emphysema grades. For patients with absent visual emphysema, mean LAV% was 2.98 ± 3.30, for patients with trace emphysema 3.22 ± 2.75, for patients with mild emphysema 3.90 ± 3.33, for patients with moderate emphysema 6.41 ± 3.46, for patients with confluent emphysema 9.02 ± 5.45, and for patients with destructive emphysema 16.90 ± 8.19. Optimal LAV% cutoff value for predicting a FEV1/FVC < 70 was 6.1 (area under the curve = 0.764, sensitivity = 0.773, specificity = 0.665), while for predicting a visual emphysema grade of moderate or higher, it was 4.7 (area under the curve = 0.802, sensitivity = 0.766, specificity = 0.742). Furthermore, correlation between visual emphysema grading and FEV1/FVC was found. In patients with FEV1/FVC < 70% a high proportion of subjects had emphysema grade 3 (moderate) or higher, whereas in patients with FEV1/FVC ≥ 70%, a larger proportion had emphysema grade 3 (moderate) or lower. The sensitivity for visual emphysema grading predicting a FEV1/FVC < 70% was 56.3% with an optimal cutoff point at a visual grade of 4 (confluent), demonstrating a lower sensitivity compared with LAV% (77.3%). CONCLUSIONS: A significant correlation between AI-based LAV% and FEV1/FVC as well as visual CT emphysema grades can be found in routine chest CT suggesting that AI-based LAV% measurement might be integrated as an add-on functional parameter in the evaluation of chest CT in the future.

Distal Kaplan fibers and anterolateral ligament injuries are associated with greater intra-articular internal tibial rotation in ACL-deficient knees based on magnetic resonance imaging.

PURPOSE: The purpose of the present study was to assess the internal rotation of the tibia on Magnetic Resonance Imaging (MRI) in a series of consecutive athletes with Anterior cruciate Ligament (ACL) tears. METHODS: Retrospective analysis of prospectively collected data was performed to include all consecutive patients who had undergone primary ACL reconstruction between January 2022 and June 2022. The angle between surgical epicondylar axes (SEA) of the knee and posterior tibial condyles (PTC) was measured. A negative value was defined as internal torsion. KFs and ALL injuries were reported. Analysis of covariance (ANCOVA) was performed to examine the independent associations between SEA-PTC angle and injuries of KFs and ALL adjusted for physical variables (age, gender and body mass index [BMI]). Statistical significance was set at a p-value of < 0.05. RESULTS: A total of 83 eligible patients were included. The result of multiple linear regression analysis showed that internal tibial rotation was associated with KFs and ALL injuries. The estimated average of SEA-PTC angle in relation to ALL injuries controlling the other variables was -5.49 [95%CI -6.79 - (-4.18)] versus -2.99 [95%CI -4.55 - (-1.44)] without ALL injuries. On the other hand, the estimated average of SEA-PTC angle in relation to KFs lesions controlling the other variables was -5.73 [95%CI -7.04 - (-4.43)] versus -2.75 [95%CI -4.31 - (-1.18)] without KFs injuries. CONCLUSIONS: KFs and ALL injuries were associated with an increased intra-articular internal tibial rotation in ACL-deficient knees. The measurement of femorotibial rotation on axial MRI could be useful to detect indirect signs of anterolateral complex (ALC) injuries.

An integrated systems biology approach reveals differences in formate metabolism in the genus Methanothermobacter.

Methanogenesis allows methanogenic archaea to generate cellular energy for their growth while producing methane. Thermophilic hydrogenotrophic species of the genus Methanothermobacter have been recognized as robust biocatalysts for a circular carbon economy and are already applied in power-to-gas technology with biomethanation, which is a platform to store renewable energy and utilize captured carbon dioxide. Here, we generated curated genome-scale metabolic reconstructions for three Methanothermobacter strains and investigated differences in the growth performance of these same strains in chemostat bioreactor experiments with hydrogen and carbon dioxide or formate as substrates. Using an integrated systems biology approach, we identified differences in formate anabolism between the strains and revealed that formate anabolism influences the diversion of carbon between biomass and methane. This finding, together with the omics datasets and the metabolic models we generated, can be implemented for biotechnological applications of Methanothermobacter in power-to-gas technology, and as a perspective, for value-added chemical production.

Optical Measurement of Ligament Strain: Opportunities and Limitations for Intraoperative Application.

A feasible and precise method to measure ligament strain during surgical interventions could significantly enhance the quality of ligament reconstructions. However, all existing scientific approaches to measure in vivo ligament strain possess at least one significant disadvantage, such as the impairment of the anatomical structure. Seeking a more advantageous method, this paper proposes defining medical and technical requirements for a non-destructive, optical measurement technique. Furthermore, we offer a comprehensive review of current optical endoscopic techniques which could potentially be suitable for in vivo ligament strain measurement, along with the most suitable optical measurement techniques. The most promising options are rated based on the defined explicit and implicit requirements. Three methods were identified as promising candidates for a precise optical measurement of the alteration of a ligaments strain: confocal chromatic imaging, shearography, and digital image correlation.

Concomitant Injuries Associated With ACL Rupture in Elite Professional Alpine Ski Racers and Soccer Players: A Comparative Study With Propensity Score Matching Analysis.

Background: For elite professional soccer players and alpine skiers, injuries associated with anterior cruciate ligament (ACL) rupture, such as meniscal, cartilage, or collateral ligament lesions, could result in a delayed return to sport compared with isolated ACL injury. Purpose/Hypothesis: The purpose of the study was to provide a detailed description of associated injuries at the time of primary ACL reconstruction in elite soccer players and alpine skiers. It was hypothesized that soccer players and skiers would present different typical injury patterns due to different injury mechanisms. Study Design: Cohort study; Level of evidence, 3. Methods: Surgical reports and arthroscopic images of elite professional soccer players and alpine skiers who underwent primary ACL reconstruction at a single institution between January 2010 and June 2022 were analyzed retrospectively. The presence and location of multiligamentous injury, meniscal tears, and chondral lesions were compared between the athlete groups. A propensity score matching analysis with 1:1 ratio was performed between skiers and soccer players to limit the effect of selection bias. Results: Included were ACL reconstruction data representative of 37 soccer players and 44 alpine skiers. Meniscal pathology was found in 32 (86%) soccer players and 30 (68%) skiers. Chondral injuries were reported in 11 (30%) soccer players and 15 (34%) skiers. Results of the propensity score matching analysis in 15 pairs of soccer players and skiers indicated that soccer players had a significantly higher rate of medial meniscal injuries (73% vs 27%; P = .03) and lateral posterior root tears (33% vs 0%; P = .04) compared with skiers. Conclusion: A higher prevalence of combined chondral and meniscal injuries versus isolated ACL injuries was observed in both groups of athletes. Professional soccer players were characterized by higher prevalence of medial meniscal tears and lateral posterior root lesions compared with professional alpine skiers.

A Congressional Twitter network dataset quantifying pairwise probability of influence.

We present a social network dataset based on interactions between members of the 117th United States Congress between Feb. 9, 2022, and June 9, 2022. The dataset takes the form of a directed, weighted network in which the edge weights are empirically obtained "probabilities of influence" between all pairs of Congresspeople. Twitter's application programming interface (API) V2 was used to determine the number of times each member of Congress retweeted, quote tweeted, replied to, or mentioned other Congressional members, and the probability of influence was found by normalizing the summed influence by the number of tweets issued by each Congressperson. This network may be of particular interest to the study of information diffusion within social networks.

The Targeted Deletion of Genes Responsible for Expression of the Mth60 Fimbriae Leads to Loss of Cell-Cell Connections in Methanothermobacter thermautotrophicus ΔH.

This study is a continuation by the Environmental Biotechnology Group of the University of Tübingen in memoriam to Reinhard Wirth, who initiated the work on Mth60 fimbriae at the University of Regensburg. Growth in biofilms or biofilm-like structures is the prevailing lifestyle for most microbes in nature. The first crucial step to initiate biofilms is the adherence of microbes to biotic and abiotic surfaces. Therefore, it is crucial to elucidate the initial step of biofilm formation, which is generally established through cell-surface structures (i.e., cell appendages), such as fimbriae or pili, that adhere to biotic and abiotic surfaces. The Mth60 fimbriae of Methanothermobacter thermautotrophicus ΔH are one of only a few known archaeal cell appendages that do not assemble via the type IV pili assembly mechanism. Here, we report the constitutive expression of Mth60 fimbria-encoding genes from a shuttle-vector construct and the deletion of the Mth60 fimbria-encoding genes from the genomic DNA of M. thermautotrophicus ΔH. For this, we expanded our system for genetic modification of M. thermautotrophicus ΔH using an allelic-exchange method. While overexpression of the respective genes increased the number of Mth60 fimbriae, deletion of the Mth60 fimbria-encoding genes led to a loss of Mth60 fimbriae in planktonic cells of M. thermautotrophicus ΔH compared to the wild-type strain. This, either increased or decreased, number of Mth60 fimbriae correlated with a significant increase or decrease of biotic cell-cell connections in the respective M. thermautotrophicus ΔH strains compared to the wild-type strain. IMPORTANCE Methanothermobacter spp. have been studied for the biochemistry of hydrogenotrophic methanogenesis for many years. However, a detailed investigation of certain aspects, such as regulatory processes, was impossible due to the lack of genetic tools. Here, we amend our genetic toolbox for M. thermautotrophicus ΔH with an allelic exchange method. We report the deletion of genes that encode the Mth60 fimbriae. Our findings provide the first genetic evidence of whether the expression of these genes underlies regulation and reveal a role of the Mth60 fimbriae in the formation of cell-cell connections of M. thermautotrophicus ΔH.

The "Bankart knee": high-grade impression fractures of the posterolateral tibial plateau lead to increased translational and anterolateral rotational instability of the ACL-deficient knee.

PURPOSE: The aim of this biomechanical cadaver study was to evaluate the effects of high-grade posterolateral tibia plateau fractures on the kinematics of anterior cruciate ligament (ACL)-deficient joints; it was hypothesized that, owing to the loss of the integrity of the osseous support of the posterior horn of the lateral meniscus (PHLM), these fractures would influence the biomechanical function of the lateral meniscus (LM) and consequently lead to an increase in anterior translational and anterolateral rotational (ALR) instability. METHODS: Eight fresh-frozen cadaveric knees were tested using a six-degree-of-freedom robotic setup (KR 125, KUKA Robotics, Germany) with an attached optical tracking system (Optotrack Certus Motion Capture, Northern Digital, Canada). After the passive path from 0 to 90° was established, a simulated Lachman test and pivot-shift test as well as external rotation (ER) and internal rotation (IR) were applied at 0°, 30°, 60° and 90° of flexion under constant 200 N axial loading. All of the parameters were initially tested in the intact and ACL-deficient states, followed by two different types of posterolateral impression fractures. The dislocation height was 10 mm, and the width was 15 mm in both groups. The intraarticular depth of the fracture corresponded to half of the width of the posterior horn of the lateral meniscus in the first group (Bankart 1) and 100% of the meniscus width in the second group (Bankart 2). RESULTS: There was a significant decrease in knee stability after both types of posterolateral tibial plateau fractures in the ACL-deficient specimens, with increased anterior translation in the simulated Lachman test at 0° and 30° of knee flexion (p = 0.012). The same effect was seen with regard to the simulated pivot-shift test and IR of the tibia (p = 0.0002). In the ER and posterior drawer tests, ACL deficiency and concomitant fractures did not influence knee kinematics (n.s.). CONCLUSION: This study demonstrates that high-grade impression fractures of the posterolateral aspect of the tibial plateau increase the instability of ACL-deficient knees and result in an increase in translational and anterolateral rotational instability.

Influence of contrast agent on artificial intelligence-based CT low attenuation volume percentage measurement.

BACKGROUND: Low attenuation volume percentage (LAV%) has been identified as a quantitative imaging biomarker for emphysema with good correlation with spirometry. The influence of intravenous contrast agent on LAV% and its correlation with spirometry is not well known. PURPOSE: To evaluate the influence of intravenous contrast agent on artificial intelligence (AI)-based LAV% in correlation with spirometric Tiffeneau-Pinelli Index (TI). MATERIAL AND METHODS: In a retrospective study, two groups of 47 patients (mean age 68.04 ± 12.64 and 67.89 ± 11.54 years) with either non-enhanced chest computed tomography (CT) or contrast-enhanced CT were compared. Using an AI-based software, LAV% was quantified using a threshold <-950 HU. TI was calculated from spirometry and pathologic airway obstruction was considered with a TI <70. The effect of contrast agent on LAV% and the relationship between TI and LAV% was analyzed. Correlation coefficients between TI and LAV% were compared for both groups. RESULTS: Patients with non-enhanced CT had a mean LAV% of 9.07 ± 7.53. Of them, 22 patients had a TI <70% and 25 patients a TI ≥70%. Patients with contrast-enhanced CT had a mean LAV% of 6.54 ± 4.62. Of them, 20 patients had a TI <70% and 27 patients had a TI ≥70%. Contrast agent did not show a major effect on LAV% (P = 0.099) and the relationship between TI and LAV% (P = 0.88). In both groups, a significant correlation between TI and LAV% was found (ρ = -0.317 for non-enhanced CT; ρ = -0.514 for contrast-enhanced CT). Difference between correlation coefficients was insignificant. CONCLUSION: Our findings suggest that contrast agent does not influence LAV% nor its correlation with TI.

Return to Play and Pattern of Injury After ACL Rupture in a Consecutive Series of Elite UEFA Soccer Players.

Background: Anterior cruciate ligament rupture represents a career-threatening injury for professional soccer players. Purpose: To analyze the pattern of injury, return to play (RTP), and performance of a consecutive series of elite professional soccer players after anterior cruciate ligament reconstruction (ACLR). Study Design: Case series; Level of evidence, 4. Methods: We evaluated the medical records of 40 consecutive elite soccer players who underwent ACLR by a single surgeon between September 2018 and May 2022. Patient age, height, weight, body mass index, position, injury history, affected side, RTP time, minutes played per season (MPS), and MPS as a percentage of playable minutes before and after ACLR were retrieved from medical records and from publicly available media-based platforms. Results: Included were 27 male patients (mean ± SD age at surgery, 23.2 ± 4.3 years; range, 18-34 years). The injury occurred during matches in 24 players (88.9%), with a noncontact mechanism in 22 (91.7%). Meniscal pathology was found in 21 patients (77.8%). Lateral meniscectomy and meniscal repair were performed in 2 (7.4%) and 14 (51.9%) patients, respectively, and medial meniscectomy and meniscal repair were performed in 3 (11.1%) and 13 (48.1%) patients, respectively. A total of 17 players (63.0%) underwent ACLR with bone-patellar tendon-bone autograft and 10 (37.0%) with soft tissue quadriceps tendon. Lateral extra-articular tenodesis was added in 5 patients (18.5%). The overall RTP rate was 92.6% (25 of 27). Two athletes moved to a lower league after surgery. The mean MPS% during the last preinjury season was 56.69% ± 21.71%; this decreased significantly to 29.18% ± 20.6% (P < .001) in the first postoperative season and then increased to 57.76% ± 22.89% and 55.89% ± 25.8% in the second and third postoperative seasons. Two (7.4%) reruptures and 2 (7.4%) failed meniscal repairs were reported. Conclusion: ACLR in elite UEFA soccer players was associated with a 92.6% rate of RTP and 7.4% rate of reinjury within 6 months after primary surgery. Moreover, 7.4% of soccer players moved to a lower league during the first season after surgery. Age, graft selection, concomitant treatments, and lateral extra-articular tenodesis were not significantly associated with prolonged RTP.

Posterior Cruciate Ligament Reconstruction Using Flat Soft-Tissue Grafts.

Isolated posterior cruciate ligament (PCL) ruptures are relatively rare, but they more commonly occur in multiligament knee injuries. To date, in isolated or combined injuries with grade III step-off, surgical treatment is recommended to restore joint stability and improve knee function. Several techniques for PCL reconstruction have been described. However, recent evidence has suggested that broad, flat soft-tissue grafts may more closely mimic the native PCL ribbonlike morphology in PCL reconstruction. Furthermore, a femoral rectangular bone tunnel may more accurately re-create the native PCL attachment, allowing grafts to simulate native PCL rotation during knee flexion and potentially improving biomechanics. Therefore, we have developed a PCL reconstruction technique using flat quadriceps or hamstring grafts. This technique can be performed using 2 types of surgical instruments that allow for the creation of a rectangular femoral bone tunnel.