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Quadriceps rate of torque development (RTD) and torque steadiness are valuable metrics for assessing explosive strength and the ability to control force over a sustained period of time, which can inform clinical assessments of knee function. Despite their widespread use, there is a significant gap in standardized methodology for measuring these metrics, which limits their utility in comparing outcomes across different studies and populations. To address these gaps, we evaluated the influence of sampling rates, signal filtering, and torque onset detection on RTD and torque steadiness. Twenty-seven participants with a history of a primary anterior cruciate ligament reconstruction (N = 27 (11 male/16 female), age = 23 ± 8 years, body mass index = 26 ± 4 kg/m2) and thirty-two control participants (N = 32 (13 male/19 female), age = 23 ± 7 years, body mass index = 23 ± 3 kg/m2) underwent isometric quadriceps strength testing, with data collected at 2222 Hz on an isokinetic dynamometer. The torque–time signal was downsampled to approximately 100 and 1000 Hz and processed using a low-pass, zero-lag Butterworth filter with a range of cutoff frequencies spanning 10–200 Hz. The thresholds used to detect torque onset were defined as 0.1 Nm, 1 Nm, and 5 Nm. RTD between 0 and 100 ms, 0 and 200 ms, and 40–160 ms was computed, as well as absolute and relative torque steadiness. Relative differences were computed by comparing all outcomes to the “gold standard” values computed, with a sampling rate of 2222 Hz, a cutoff frequency in the low-pass filter of 150 Hz, and torque onset of 1 Nm, and compared utilizing linear mixed models. While all combinations of signal collection and processing parameters reached statistical significance (p < 0.05), these differences were consistent between injured and control limbs. Additionally, clinically relevant differences (+/−10%) were primarily observed through torque onset detection methods and primarily affected RTD between 0 and 100 ms. Although measurements of RTD and torque steadiness were generally robust against diverse signal collection and processing parameters, the selection of torque onset should be carefully considered, especially in early RTD assessments that have shorter time epochs.

Susan McKenzie,1 Annette Burgess,2 Craig Mellis1 1Central Clinical School, Sydney Medical School, The University of Sydney, Sydney, NSW, Australia; 2Education Office, Sydney Medical School, The University of Sydney, Sydney, NSW, AustraliaCorrespondence: Susan McKenzieCentral Clinical School, Sydney Medical School, The University of Sydney, Building 63, Level 4, Royal Prince Alfred Hospital, Missenden Road, Camperdown, Sydney, NSW 2050, AustraliaTel +61 2 9515 6548Email susan.mckenzie@sydney.edu.auIntroduction: Medical students extend their preparatory learning on entering the clinical work environment, by joining their clinical team as peripheral participants and start to care for “real” patients. This learning is situated, experiential, varied, mainly unstructured, highly dependent on clinical opportunities (affordances), and students’ motivation to learn (learner agency). Students ideally contribute to workplace activities, which allow their practical skills, confidence and professional identity to evolve. This study sought to investigate senior students’ perspectives in their early stages of workplace learning, by using social learning theory as a framework. The focus is on team integration, practical skills performance, professional development and their evolving professional identity.Methods: Between 2015 and 2018, we conducted five focus groups, with a total of 36 volunteers, out of a possible 200 (18% Stage 3 (Year 3)) medical students. Each focus group session was audio recorded and transcribed verbatim. Participants were de-identified, and framework analysis used the theoretical frameworks of communities of practice, and workplace affordances to gain insight into their work-place learning experience during the first two months of their clinical rotation.Results: Thirty-six students out of 200 (18%) attended focus groups over a four-year period. The results are presented using the theoretical frameworks of community of practice and workplace affordances and presented as themes of: meaning, “learning as experience”, practice, “learning as doing” community, “learning as belonging”, and identity, “learning as becoming”.Discussion: Participants reported many positive examples of workplace learning while dealing directly with patients. Students were also exposed to ethical dilemmas and unexpected risks in the workplace. These included lack of site orientation, unsupportive teams, lack of supervision, and students’ inability to initiate agency, all of which contributed to their workplace uncertainty. Performing manageable tasks for their team provided a role in their community of practice, strengthening their identity as evolving doctors. Exposure to both positive and negative role models allowed students to reflect on ethical issues, further extending their own professional identities.Summary: Participants were quick to observe and report workplace dynamics as they were exposed to the positive and negative aspects of the hidden curriculum. This allowed them to reflect on patient safety, and ethical concerns promoting the development of their professional identity.Keywords: third-year medicine, workplace learning, professional identity, role modelling, communities of practice

IntroductionDespite rigorous rehabilitation aimed at restoring muscle health, anterior cruciate ligament (ACL) injury is often hallmarked by significant long-term quadriceps muscle weakness. Derangements in mitochondrial function are a common feature of various atrophying conditions, yet it is unclear to what extent mitochondria are involved in the detrimental sequela of quadriceps dysfunction after ACL injury. Using a preclinical, non-invasive ACL injury rodent model, our objective was to explore the direct effect of an isolated ACL injury on mitochondrial function, muscle atrophy, and muscle phenotypic transitions.MethodsA total of 40 male and female, Long Evans rats (16-week-old) were exposed to non-invasive ACL injury, while 8 additional rats served as controls. Rats were euthanized at 3, 7, 14, 28, and 56 days after ACL injury, and vastus lateralis muscles were extracted to measure the mitochondrial respiratory control ratio (RCR; state 3 respiration/state 4 respiration), mitochondrial reactive oxygen species (ROS) production, fiber cross sectional area (CSA), and fiber phenotyping. Alterations in mitochondrial function and ROS production were detected using two-way (sex:group) analyses of variance. To determine if mitochondrial characteristics were related to fiber atrophy, individual linear mixed effect models were run by sex.ResultsMitochondria-derived ROS increased from days 7 to 56 after ACL injury (30–100%, P < 0.05), concomitant with a twofold reduction in RCR (P < 0.05). Post-injury, male rats displayed decreases in fiber CSA (days 7, 14, 56; P < 0.05), loss of IIa fibers (day 7; P < 0.05), and an increase in IIb fibers (day 7; P < 0.05), while females displayed no changes in CSA or phenotyping (P > 0.05). Males displayed a positive relationship between state 3 respiration and CSA at days 14 and 56 (P < 0.05), while females only displayed a similar trend at day 14 (P = 0.05).ConclusionLong-lasting impairments in quadriceps mitochondrial health are present after ACL injury and play a key role in the dysregulation of quadriceps muscle size and composition. Our preclinical data indicate that using mitoprotective therapies may be a potential therapeutic strategy to mitigate alterations in muscle size and characteristic after ACL injury.

Susan McKenzie,1 Craig Mellis2 1Central Clinical School, 2Education Office, Sydney Medical School, The University of Sydney, Sydney, NSW, 2050, Australia Introduction: On commencing internship, new medical graduates (new interns) are often required to perform core procedural skills under differing levels of supervision. This variability of knowledge and experience with procedural skills can place patient safety at risk. Consequently, in 2012, we developed a targeted, intensive, 3-day training course for our pre-intern (PrInt) students. The aim of this study was to evaluate the intern preparation package by exploring interns’ self-reported knowledge, confidence, and experience in key procedural skills during the early months of internship.Methods: Between 2012 and 2016, 5 cohorts of PrInt students (n=223) participated in our course. In the following years 2013–2017, the same 5 cohorts, at 4–5 months into their internship, were surveyed anonymously and invited to attend focus groups. Descriptive statistics and thematic analysis were used to analyze data.Results: Of the 223 interns, 91 (41%) responded. Of the 91, 82 (93%) agreed that the intern preparation package provided during PrInt had been beneficial to their practice as an intern. Awareness of potential risks to patient safety was high, ranging from infection control at 89/89 (100%) to 87/90 (97%) for patient identification. Confidence in performing procedural skills varied from moderate in identifying nasogastric tube placement on X-ray (66/89; 85%), to equal least confidence in managing cardiac-related emergencies (53/90; 59%) and identifying the correct placement of peripherally inserted central catheter lines on X-ray (52/89; 58%).Major qualitative findings: The preparation package had refreshed interns’ procedural skills ability and awareness of risks to patient safety. Integration into the clinical team was positive, but requests to perform procedural skills on day 1 was unexpected.Conclusion: Interns reported that they had gained substantial benefit from their preparation package, and they performed practical procedures from day 1, further highlighting the need for an intensive preparation course immediately prior to entering internship. Keywords: preparation for medical internship, procedural skills, new interns, junior doctors, teamwork, transitions, patient safety

Susan McKenzie,1 Annette Burgess,2 Craig Mellis1 1Central Clinical School, 2Education Office, Sydney Medical School, The University of Sydney, Sydney, NSW, Australia Background: It is widely known that the opportunity for medical students to be observed and to receive feedback on their procedural skills performance is variable in the senior years. To address this problem, we provided our Pre-Intern (PrInt) students with “one-to-one” formative feedback on their ability to perform urethral catheterization (U/C) and hypothesized that their future practice of U/C as interns would benefit. This study sought to evaluate the performance and practice of interns in U/C 4–5 months after having received feedback on their performance of U/C as PrInt students.Methods: Between 2013 and 2014, two cohorts of interns, (total n=66) who had received recent formative feedback on their U/C performance as PrInt students at Central Clinical School, were invited to complete an anonymous survey. The survey contained nine closed unvalidated questions and one open-ended question, designed to allow interns to report on their current practice of U/C.Results: Forty-one out of 66 interns (62%) completed the survey. Thirty-five out of 41 respondents (85%) reported that the assessment with feedback during their PrInt term was beneficial to their practice. Thirty of 41 (73%) reported being confident to perform U/C independently. Eleven out of 41 respondents (27%) reported that they had received additional training at intern orientation. Nine of the 11 interns (82%) reported that they had a small, but a significant, increase in confidence to perform U/C when compared with the 30 of the 41 respondents (73%) who had not (p=0.03).Conclusion: Our results substantiate our hypothesis that further education by assessment with feedback in U/C during PrInt was of benefit to interns’ performance. Additional educational reinforcement in U/C during intern orientation further improved intern confidence. Our results indicate that extra pre- and post-graduation procedural skills training, with feedback, should be universal. Keywords: formative assessment with feedback, performance and practice of new interns, medical interns, urinary catheterization, pre-intern students

Susan McKenzie, Craig Mellis Central Clinical School, Sydney Medical School, The University of Sydney, NSW, Australia Background: Graduating medical students enter their internship with varied levels of practical experience in procedural skills. To address this problem, many medical schools have introduced intensive skill training courses immediately prior to graduation. This study examines the impact of a pre-intern (PrInt) education package, consisting of a short intensive course, followed by a one-month clinical attachment. Methods: In September 2014, all PrInt students (n = 53) at the Central Clinical School (Sydney, NSW, Australia) attended three days of intensive training. This included a didactic introduction, case-based scenarios, and interactive workshops. This was followed by four weeks of targeted, experiential learning during a clinical attachment (PrInt term). Immediately prior to training and following PrInt, all students were invited to complete a six-domain questionnaire containing 40 subscale closed questions to assess their knowledge, experience, and confidence in key practical skills essential for a successful internship. Results: A total of 41/53 (77%) students completed an identical questionnaire prior to PrInt, and 37/53 (70%) immediately following PrInt. Respondents reported statistically significant increases in their experience, ability, knowledge, and confidence in a number of domains. The key changes were the following: knowledge of pharmacy skills (mean improvement = 26.48, confidence interval 95% [CI 95%] = 17.29–35.66, p ≤ 0.0001) and management of procedural skills (mean = 24.46, CI 95% = 16.58–32.34, p ≤ 0.0001). Despite the positive overall increase in most domains, some subscale results remained low following the educational package; only 44% students had inserted a nasogastric tube; only 44% reported confidence in commencing patients on warfarin; and only 42% in managing a hospital emergency. Surprisingly, there was a slight decline both in confidence in communicating with members of the hospital team (10%) and in awareness of the causes of hypoglycemia (7%). Conclusion: Final year students perceived substantial benefit from an educational package specifically aimed at improving their practical skills immediately prior to internship. Keywords: pre-intern induction, pre-intern students, preparedness for practice, transition, medical education, procedural skills, pre-intern accelerated learning, skills for internship

Objective. To describe the landscape of well-being content inclusion across schools and colleges of pharmacy in the United States and Canada through identification of content implementation, incorporation, and assessment.Methods. A cross-sectional survey was distributed to all accredited schools and colleges of pharmacy in the United States (n=143) and Canada (n=10). Survey questions included curricular and cocurricular timing, frequency, assessment strategies, and support for well-being initiatives, using a framework of eight dimensions (pillars) of wellness to categorize content.Results. Descriptive data analyses were applied to 99 completed surveys (65%), 89 (62%) in the United States and 10 (100%) in Canada. Well-being content was most prevalent within the cocurricular realm and incorporated into didactic and elective more than experiential curricula. The most content came from intellectual, emotional, and physical pillars, and the least content came from financial, spiritual, and environmental pillars. Less than 50% of schools and colleges of pharmacy include well-being within their strategic plans or core values. Funding is primarily at the level of the university (59%) or the school or college of pharmacy (59%). Almost half of respondents reported inclusion of some assessment, with a need for more training, expertise, and standardization.Conclusion. Survey results revealed a wide range of implementation and assessment of well-being programs across the United States and Canada. These results provide a reference point for the state of well-being programs that can serve as a call to action and research across the Academy.

Following anterior cruciate ligament reconstruction (ACLR), patients exhibit abnormal walking mechanics and quadriceps dysfunction. Quadriceps dysfunction has been largely attributed to muscle atrophy and weakness. While important, these factors do not capture intrinsic properties of muscle that govern its ability to generate force and withstand load. While fascicle abnormalities after ACLR have been documented in early stages of recovery (<12 mo), long-term effects of ACLR on fascicle mechanics remain unexplored. We evaluated quadriceps fascicle mechanics during walking 3 years post-ACLR and examined the relationship with knee mechanics. Participants included 24 individuals with ACLR and 24 Controls. Linear mixed models compared the ACLR, Contralateral, and Controls limbs for (1) quadriceps strength, (2) fascicle architecture and mechanics, and (3) knee mechanics. No difference in strength or overall fascicle length excursions was found between limbs. The ACLR limb exhibited longer fascicles at heel strike and peak knee extension moment (P <.001–.004), and smaller fascicle angles at heel strike, peak knee extension moment, and overall suppressed fascicle angle excursions (P <.001–.049) relative to the Contralateral and/or Control limb. This indicates an abnormality in fascicle architecture and mechanics following ACLR and suggests abnormalities in contractile function that cannot be explained by muscle weakness and may contribute to long-term gait irregularities. [ABSTRACT FROM AUTHOR]

Background: Both high body mass index (BMI) and anterior cruciate ligament reconstruction (ACLR) independently influence knee osteoarthritis risk. Preliminary evidence shows the combination of these risk factors leads to poorer recovery and altered biomechanical outcomes after ACLR, but few studies have directly evaluated early changes in cartilage health between normal-BMI and high-BMI groups in this population. Purpose: To evaluate ultrasound-based measures of cartilage strain and compositional changes (via echo-intensity [EI]) in response to an incline walking stress test between normal-BMI and high-BMI individuals with ACLR. A secondary evaluation was conducted of associations between habitual walking biomechanics (ie, ground-reaction forces, sagittal knee kinetics and kinematics) and cartilage strain and EI outcomes. Study Design: Controlled laboratory study. Methods: Gait biomechanics and femoral trochlear ultrasound analyses were evaluated in 64 participants with ACLR who had normal BMI (BMI < 27.0; n = 40) and high BMI (BMI ≥ 27.0; n = 24). Ultrasound images were collected bilaterally before and after an incline treadmill walk, and medial and lateral trochlear strain and EI changes pre-post exercise were used to compare BMI groups and limbs. Gait outcomes included ground-reaction forces, peak sagittal plane knee moments, angles, and excursions and were used to determine associations with cartilage outcomes in the entire cohort. Results: High-BMI individuals with ACLR exhibited greater medial trochlear cartilage strain in the ACLR limb compared with normal-BMI individuals (approximately 6%; P <.01). In those with high BMI, the ACLR limb exhibited greater medial trochlear strain relative to non-ACLR limbs (approximately 4%; P <.05), but between-limb differences were not observed in the normal-BMI group (P >.05). Medial trochlear EI changes were greater bilaterally in those with high BMI compared with normal-BMI ACLR counterparts (approximately 10%; P <.01). Last, individuals who walked with greater peak knee flexion angles exhibited less medial cartilage strain (Δ R 2 = 0.06; P =.025). Conclusion: The data suggested that high BMI affects cartilage functional properties after ACLR, whereas smaller knee flexion angles were associated with larger medial cartilage strain. Clinical Relevance: High-BMI individuals with ACLR may represent a subset of patients exhibiting earlier declines in cartilage functional integrity in response to loading, necessitating additional or more targeted interventions to mitigate disease development. [ABSTRACT FROM AUTHOR]

Muscle weakness following anterior cruciate ligament reconstruction (ACLR) increases the risk of posttraumatic osteoarthritis (OA). However, focusing solely on muscle weakness overlooks other aspects like muscle composition, which could hinder strength recovery. Intramuscular fat is a non‐contractile element linked to joint degeneration in idiopathic OA, but its role post‐ACLR has not been thoroughly investigated. To bridge this gap, we aimed to characterize quadriceps volume and intramuscular fat in participants with ACLR (male/female = 15/9, age = 22.8 ± 3.6 years, body mass index [BMI] = 23.2 ± 1.9, time since surgery = 3.3 ± 0.9 years) and in controls (male/female = 14/10, age = 22.0 ± 3.1 years, BMI = 23.3 ± 2.6) while also exploring the associations between intramuscular fat and muscle volume with isometric strength. Linear mixed effects models assessed (I) muscle volume, (II) intramuscular fat, and (III) strength between limbs (ACLR vs. contralateral vs. control). Regression analyses were run to determine if intramuscular fat or volume were associated with quadriceps strength. The ACLR limb was 8%−11% smaller than the contralateral limb (p < 0.05). No between‐limb differences in intramuscular fat were observed (p = 0.091−0.997). Muscle volume but not intramuscular fat was associated with strength in the ACLR and control limbs (p < 0.001−0.002). We demonstrate that intramuscular fat does not appear to be an additional source of quadriceps dysfunction following ACLR and that muscle size only explains some of the variance in muscle strength. [ABSTRACT FROM AUTHOR]

Purpose: High body mass index (BMI) is a strong predictor of posttraumatic osteoarthritis (OA) after anterior cruciate ligament reconstruction (ACLR). Altered gait mechanics are independently affected by BMI and ACLR, and influence OA risk. Yet, evidence directly assessing the impact of high BMI on gait or cartilage characteristics after ACLR are limited. Here, we evaluated if high BMI moderates associations between gait and trochlear cartilage structure in individuals with ACLR. Methods: Treadmill walking biomechanics were evaluated in 40 normal BMI and 24 high BMI participants with ACLR at self-selected speeds. Normalized and absolute peak and cumulative loads (i.e., impulse) were extracted for peak knee flexion and adduction moments (KFM, KAM) and vertical ground reaction force (GRF).Medial and lateral femoral cartilage thickness and medial/lateral thickness ratios were assessed via ultrasound. Results: Those with ACLR and high BMI walked with reduced normalized peak vertical GRFs, and greater absolute peak and cumulative loads compared with normal BMI individuals with ACLR. Those with ACLR and high BMI also exhibited thinner cartilage and greater medial/lateral ratios in ACLR limbs compared with contralateral limbs whereas norma lBMI individuals with ACLR exhibited thicker ACLR limb cartilage. Lastly, greater peak KAM and KAM cumulative load were associated with thicker lateral cartilage and lesser medial/lateral thickness ratios, but only in the high BMI group. Conclusions: We observed those with high BMI after ACLR exhibited trochlear cartilage structural alterations not observed in normal BMI patients, whereas differential associations between loading outcomes and cartilage thickness in ACLR knees were observed between groups. Those with high BMI after ACLR may require different therapeutic strategies to optimize joint health in this subset of patients. [ABSTRACT FROM AUTHOR]

Quadriceps rate of torque development (RTD) and torque steadiness are valuable metrics for assessing explosive strength and the ability to control force over a sustained period of time, which can inform clinical assessments of knee function. Despite their widespread use, there is a significant gap in standardized methodology for measuring these metrics, which limits their utility in comparing outcomes across different studies and populations. To address these gaps, we evaluated the influence of sampling rates, signal filtering, and torque onset detection on RTD and torque steadiness. Twenty-seven participants with a history of a primary anterior cruciate ligament reconstruction (N = 27 (11 male/16 female), age = 23 ± 8 years, body mass index = 26 ± 4 kg/m2) and thirty-two control participants (N = 32 (13 male/19 female), age = 23 ± 7 years, body mass index = 23 ± 3 kg/m2) underwent isometric quadriceps strength testing, with data collected at 2222 Hz on an isokinetic dynamometer. The torque–time signal was downsampled to approximately 100 and 1000 Hz and processed using a low-pass, zero-lag Butterworth filter with a range of cutoff frequencies spanning 10–200 Hz. The thresholds used to detect torque onset were defined as 0.1 Nm, 1 Nm, and 5 Nm. RTD between 0 and 100 ms, 0 and 200 ms, and 40–160 ms was computed, as well as absolute and relative torque steadiness. Relative differences were computed by comparing all outcomes to the "gold standard" values computed, with a sampling rate of 2222 Hz, a cutoff frequency in the low-pass filter of 150 Hz, and torque onset of 1 Nm, and compared utilizing linear mixed models. While all combinations of signal collection and processing parameters reached statistical significance (p < 0.05), these differences were consistent between injured and control limbs. Additionally, clinically relevant differences (+/−10%) were primarily observed through torque onset detection methods and primarily affected RTD between 0 and 100 ms. Although measurements of RTD and torque steadiness were generally robust against diverse signal collection and processing parameters, the selection of torque onset should be carefully considered, especially in early RTD assessments that have shorter time epochs. [ABSTRACT FROM AUTHOR]

We developed an open-sourced program that accounts for the current limitations of B-mode ultrasound and extends the clinical utility of ultrasound for assessing femoral trochlear cartilage thickness. Images were collected on 18 patients with a history of knee surgery. By failing to account for ultrasound acoustics and beam refraction, cartilage thickness was underestimated by 26% and overestimated by 0–4%, respectively (p < 0.001). Comprehensive thickness measurements achieved by measuring the Euclidean distance between every point were significantly different than traditional single-location measurements or by using the area/length (p = 0.004–0.006). Sub-regions were significantly different than all whole regions of interest (p = 0.001–0.012). [ABSTRACT FROM AUTHOR]

Abstract Background There are no criteria specifically for evaluating the quality of implementation research and recommending implementation strategies likely to have impact to practitioners. We describe the development and application of the Best Practices Tool, a set of criteria to evaluate the evidence supporting HIV-specific implementation strategies. Methods We developed the Best Practices Tool from 2022–2023 in three phases. (1) We developed a draft tool and criteria based on a literature review and key informant interviews. We purposively selected and recruited by email interview participants representing a mix of expertise in HIV service delivery, quality improvement, and implementation science. (2) The tool was then informed and revised through two e-Delphi rounds using a survey delivered online through Qualtrics. The first and second round Delphi surveys consisted of 71 and 52 open and close-ended questions, respectively, asking participants to evaluate, confirm, and make suggestions on different aspects of the rubric. After each survey round, data were analyzed and synthesized as appropriate; and the tool and criteria were revised. (3) We then applied the tool to a set of research studies assessing implementation strategies designed to promote the adoption and uptake of evidence-based HIV interventions to assess reliable application of the tool and criteria. Results Our initial literature review yielded existing tools for evaluating intervention-level evidence. For a strategy-level tool, additions emerged from interviews, for example, a need to consider the context and specification of strategies. Revisions were made after both Delphi rounds resulting in the confirmation of five evaluation domains – research design, implementation outcomes, limitations and rigor, strategy specification, and equity – and four evidence levels – best, promising, more evidence needed, and harmful. For most domains, criteria were specified at each evidence level. After an initial pilot round to develop an application process and provide training, we achieved 98% reliability when applying the criteria to 18 implementation strategies. Conclusions We developed a tool to evaluate the evidence supporting implementation strategies for HIV services. Although specific to HIV in the US, this tool is adaptable for evaluating strategies in other health areas.