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Background: Glenoid component positioning is an important and challenging aspect of total shoulder arthroplasty. The use of freehand technique with standard instrumentation or preoperative planning based on 2-dimensional computed tomography (CT) scans provides an opportunity for improvement in terms of component accuracy, precision, and deformity correction. These techniques have produced varying outcomes. Methods: Preoperative planning software (PPS), patient specific instrumentation (PSI), and intraoperative navigation (NAV) have been developed to improve the accuracy of implant placement and deformity correction with the ultimate goals of improved patient outcomes and implant longevity. Literature search was conducted on published and available studies comparing the accuracy of glenoid component placement and improvements in surgical and patient outcomes amongst the aforementioned techniques. Results: PPS, PSI, and NAV have demonstrated improved accuracy over freehand techniques with standard instrumentation. However, data demonstrating the clinical benefit and cost effectiveness of these new technologies are lacking. Discussion: In this paper, we reviewed the evidence available to answer the question of whether or not advanced shoulder arthroplasty technologies have been beneficial and reviewed future technologies in development such as virtual/mixed-reality and robotic assisted shoulder surgery. Level of Evidence: 4. [ABSTRACT FROM AUTHOR]

Background: There is minimal work defining the economic impact of resident participation in shoulder arthroplasty. Thus, this study quantified the opportunity cost of resident participation in total shoulder arthroplasty (TSA) and hemiarthroplasty (HA) by determining differences in operative time, relative value units (RVUs)/hour, and RVUs/case. Methods: A retrospective analysis of shoulder arthroplasty procedures were identified from the ACS-NSQIP database from 2006 to 2014 using CPT codes. Demographic, comorbidity, preoperative laboratory data and surgical procedure were used to develop matched cohorts. Mean differences in operative time, RVUs/case and RVUs/hour between attending-only (AO) cases and cases with resident involvement (RI) were examined. Cost analysis was performed to identify differences in RVUs generated per hour in dollars/case. Results: A total of 1786 AO and 1102 RI cases were identified. With the exception of PGY-3 and PGY-4 cases, RI cases had lower mean operative times compared to AO cases. The cost of RI was highest for PGY-3 ($199.87 per case) and PGY-4 ($9.2 9) residents with all other postgraduate years providing a cost reduction. Discussion: Involvement of residents was associated with shorter operative times leading to a savings of $29.64 per case. Involvement of intermediate-level (PGY-3) residents were associated with increased costs that ultimately decreased as residents became more senior. [ABSTRACT FROM AUTHOR]

Neck injuries in football are attributed to helmet-to-helmet contact with youth players being at greatest risk. In 2014, the National Federation of State High School Associations (NFHS) implemented rules defining illegal contact against a defenseless player above the shoulders to reduce head and neck injuries in football players. This study evaluates whether rule implementation decreased rates of high school football neck injuries presenting to the emergency department (ED) pre-rule implementation (2009–2013) to post-rule implementation (2015–2019). Data were queried from the National Electronic Injury Surveillance System for high school football players 14 to 18 years old diagnosed with a neck injury from 1 January 2009 to 31 December 2019. Narratives in the data were reviewed for mechanism of injury, setting, loss of consciousness (LOC), and type of injury. Between 2009 and 2019, an estimated 47,577 high school football neck injuries were diagnosed in EDs across the United States. 52.0% of neck injuries were sustained during competition compared to 48.0% during practice. A statistically significant (P = 0.004) decrease in neck injuries was realized from pre-rule implementation to post-rule implementation with averages of 5,278 and 3,481 injuries per year, respectively. Helmet-to-helmet neck injuries significantly (P = 0.04) decreased from pre- to post-rule implementation with averages of 851 and 508 injuries per year, respectively. Neck injuries sustained via other mechanisms were not affected by the 2014 rule implementation. This study is the first to identify a decrease in overall and helmet-to-helmet related neck injuries diagnosed in the ED following the 2014 NFHS targeting rule implementation. These findings add to the growing literature regarding the importance and efficacy of rule implementation in reducing sports-related neck injuries. [ABSTRACT FROM AUTHOR]

Study Design: Retrospective cohort analysis.Objective: The aim of this study was to compare postoperative outcomes of Coflex interspinous device versus laminectomy.Summary Of Background Data: Coflex Interlaminar Stabilization device (CID) is indicated for one- or two-level lumbar stenosis with grade 1 stable spondylolisthesis in adult patients, as an alternative to laminectomy, or laminectomy and fusion. CID provides stability against progressive spondylolisthesis, retains motion, and prevents further disc space collapse.Methods: Patients ≥18 years' old with lumbar stenosis and grade 1 stable spondylolisthesis who underwent either primary single-level decompression and implantation of CID, or single-level laminectomy alone were included with a minimum 90-day follow-up at a single academic institution. Clinical characteristics, perioperative outcomes, and postoperative complications were reviewed until the latest follow-up. χ2 and independent samples t tests were used for analysis.Results: Eighty-three patients (2007-2019) were included: 37 cases of single-level laminectomy (48.6% female) were compared to 46 single-level CID (50% female). CID cohort was older (CID 69.0 ± 9.4 vs. laminectomy 64.2 ± 11.0, P = 0.042) and had higher American Society of Anesthesiologists (ASA) grade (CID 2.59 ± 0.73 vs. laminectomy 2.17 ± 0.48, P = 0.020). CID patients had higher estimated blood loss (EBL) (97.50 ± 77.76 vs. 52.84 ± 50.63 mL, P = 0.004), longer operative time (141.91 ± 47.88 vs. 106.81 ± 41.30 minutes, P = 0.001), and longer length of stay (2.0 ± 1.5 vs. 1.1 ± 1.0 days, P = 0.001). Total perioperative complications (21.7% vs. 5.4%, P = 0.035) and instrumentation-related complication was higher in CID (10.9% vs. 0% laminectomy group, P = 0.039). There were no other significant differences between the groups in demographics or outcomes.Conclusion: Single-level CID devices had higher perioperative 90-day complications, longer operative time, length of stay, higher EBL compared to laminectomies alone. Similar overall revision and neurologic complication rates were noted compared to laminectomy at last follow-up.Level of Evidence: 3. [ABSTRACT FROM AUTHOR]

Objective: Photodynamic therapy (PDT) is a minimally invasive method with strong tissue selectivity and nonthermal effects. We aim to investigate the efficacy of an in‐office method utilizing PDT with local application of 5‐aminolevulinic acid (ALA) and 635 nm diode laser for treating laryngeal leukoplakia. Study Design: Retrospective cohort study. Setting: Outpatient clinic‐tertiary medical center. Methods: This study reviewed 32 patients with laryngeal leukoplakia, including 11 recurrent cases after surgery. All the procedures were performed in an office setting under topical anesthesia. Fifteen percent ALA solution was locally applied to the lesion through a flexible laryngoscope. Light illumination was performed using a 635 nm diode laser through a 400 μm optic fiber. The power density was 165 mW/cm2 to reach 100 J/cm2. Results of laryngostroboscopy and voice evaluation during follow‐up were collected. Results: The mean follow‐up was 7.91 ± 4.83 (3‐18) months. Thirty‐nine procedures were performed, including 1 session for 27 patients, 2 sessions for 3 patients, and 3 sessions for 2 patients. The total response rate was 96.875% (31/32), including complete responses in 26 (81.25%) patients, partial responses in 5 patients (15.625%), and no response in 1 patient (3.125%). It appeared that PDT selectively eliminated the leukoplakia without affecting lamina propria and the surrounding normal mucosa remained unharmed. Scores of Voice Handicap Index‐10, jitter, shimmer, and harmonic‐to‐noise ratio were significantly improved after PDT. Conclusion: Office‐based PDT is an effective, repeatable, and practical method for treating laryngeal leukoplakia. Local application of ALA is sufficient to achieve photodynamic reactions. PDT could eliminate laryngeal leukoplakia selectively while protecting the normal laryngeal structure. [ABSTRACT FROM AUTHOR]

The tasks with continuous state and action spaces are difficult to be solved with high sample efficiency. Model learning and planning, as a well-known method to improve the sample efficiency, is achieved by learning a system dynamics model first and then using it for planning. However, the convergence of the algorithm will be slowed if the system dynamics model is not captured accurately, with the consequence of low sample efficiency. Therefore, to solve the problems with continuous state and action spaces, a model-learning-based actor-critic algorithm with the Gaussian process approximator is proposed, named MLAC-GPA, where the Gaussian process is selected as the modeling method due to its valuable characteristics of capturing the noise and uncertainty of the underlying system. The model in MLAC-GPA is firstly represented by linear function approximation and then modeled by the Gaussian process. Afterward, the expectation value vector and the covariance matrix of the model parameter are estimated by Bayesian reasoning. The model is used for planning after being learned, to accelerate the convergence of the value function and the policy. Experimentally, the proposed method MLAC-GPA is implemented and compared with five representative methods in three classic benchmarks, Pole Balancing, Inverted Pendulum, and Mountain Car. The result shows MLAC-GPA overcomes the others both in learning rate and sample efficiency. [ABSTRACT FROM AUTHOR]

Key message: Mapping studies confirm that resistance to Ug99 race of stem rust pathogen in Aegilops tauschii accession Clae 25 is conditioned by Sr46 and markers linked to the gene were developed for marker-assisted selection. Abstract: The race TTKSK (Ug99) of Puccinia graminis f. sp. tritici, the causal pathogen for wheat stem rust, is considered as a major threat to global wheat production. To address this threat, researchers across the world have been devoted to identifying TTKSK-resistant genes. Here, we report the identification and mapping of a stem rust resistance gene in Aegilops tauschii accession CIae 25 that confers resistance to TTKSK and the development of molecular markers for the gene. An F population of 710 plants from an Ae. tauschii cross CIae 25 × AL8/78 were first evaluated against race TPMKC. A set of 14 resistant and 116 susceptible F families from the F plants were then evaluated for their reactions to TTKSK. Based on the tests, 179 homozygous susceptible F plants were selected as the mapping population to identify the simple sequence repeat (SSR) and sequence tagged site (STS) markers linked to the gene by bulk segregant analysis. A dominant stem rust resistance gene was identified and mapped with 16 SSR and five new STS markers to the deletion bin 2DS5-0.47-1.00 of chromosome arm 2DS in which Sr46 was located. Molecular marker and stem rust tests on CIae 25 and two Ae. tauschii accessions carrying Sr46 confirmed that the gene in CIae 25 is Sr46. This study also demonstrated that Sr46 is temperature-sensitive being less effective at low temperatures. The marker validation indicated that two closely linked markers Xgwm210 and Xwmc111 can be used for marker-assisted selection of Sr46 in wheat breeding programs. [ABSTRACT FROM AUTHOR]

Sweet sorghum bagasse (SSB) was steam pretreated in the conditions of 190 °C for 5 min to assess its amenability to the pretreatment and enzymatic hydrolysis. Results showed that pretreatment conditions were robust enough to pretreat SSB with maximum of 87% glucan and 72% xylan recovery. Subsequent enzymatic hydrolysis showed that the pretreated SSB at 2% substrate consistency resulted in maximum of 70% glucan-glucose conversion. Increasing substrate consistency from 2% to 16% led to a significant reduction in glucan conversion. However, the decrease ratio of glucan-glucose conversion was the minimum when the consistency increased from 2% to 12%. When the pretreated SSB consistency of 12% was applied for hydrolysis, increase in cellulase loading from 7.5 up to 20 filter paper units (FPU)/g glucan resulted only in 14% increase in glucan-glucose conversion compared to 20% increase with cellulase loading varying from 2.5 to 7.5 FPU/g glucan. More than 10 cellobiase units (CBU)/g glucan β-glucosidase supplementation had no noticeable improvement on glucan-glucose conversion. Additionally, supplementation of xylanase was found to significantly increase glucan-glucose conversion from 50% to 80% with the substrate consistency of 12%, when the cellulase and β-glucosidase loadings were at relatively low enzyme loadings (7.5 FPU/g and 10 CBU/g glucan). It appeared that residual xylan played a critical role in hindering the ease of hydrolysis of SSB. A proper xylanase addition was suggested to achieve a high hydrolysis yield at relatively high substrate consistency with relatively low enzyme loadings. [ABSTRACT FROM AUTHOR]