Use and Application of Large Language Models for Patient Questions Following Total Knee Arthroplasty.

BACKGROUND: A consumer-focused health care model not only allows unprecedented access to information, but equally warrants consideration of the appropriateness of providing accurate patient health information. Nurses play a large role in influencing patient satisfaction following total knee arthroplasty (TKA), but they come at a cost. A specific natural language artificial intelligence (AI) model, ChatGPT (Chat Generative Pre-trained Transformer), has accumulated over 100 million users within months of launching. As such, we aimed to compare: (1) orthopaedic surgeons' evaluation of the appropriateness of the answers to the most frequently asked patient questions after TKA; and (2) patients' comfort level in answering their postoperative questions by using answers provided by arthroplasty-trained nurses and ChatGPT. METHODS: We prospectively created 60 questions based on the most commonly asked patient questions following TKA. There were 3 fellowship-trained surgeons who assessed the answers provided by arthroplasty-trained nurses and ChatGPT-4 to each of the questions. The surgeons graded each set of responses based on clinical judgment as: (1) "appropriate," (2) "inappropriate" if the response contained inappropriate information, or (3) "unreliable," if the responses provided inconsistent content. Patients' comfort level and trust in AI were assessed using Research Electronic Data Capture (REDCap) hosted at our local hospital. RESULTS: The surgeons graded 44 out of 60 (73.3%) responses for the arthroplasty-trained nurses and 44 out of 60 (73.3%) for ChatGPT to be "appropriate." There were 4 responses graded "inappropriate" and one response graded "unreliable" provided by the nurses. For the ChatGPT response, there were 5 responses graded "inappropriate" and no responses graded "unreliable." There were 136 patients (53.8%) who were more comfortable with the answers provided by ChatGPT compared to 86 patients (34.0%) who preferred the answers from arthroplasty-trained nurses. Of the 253 patients, 233 (92.1%) were uncertain if they would trust AI to answer their postoperative questions. There were 127 patients (50.2%) who answered that if they knew the previous answer was provided by ChatGPT, their comfort level in trusting the answer would change. CONCLUSIONS: One potential use of ChatGPT can be found in providing appropriate answers to patient questions after TKA. At our institution, cost expenditures can potentially be minimized while maintaining patient satisfaction. Inevitably, successful implementation is dependent on the ability to provide information that is credible and in accordance with the objectives of both physicians and patients. LEVEL OF EVIDENCE: III.

Neighborhood socioeconomic disadvantages associated with increased rates of revisions, readmissions, and complications after total joint arthroplasty.

INTRODUCTION: Low socioeconomic status based on neighborhood of residence has been suggested to be associated with poor outcomes after total joint arthroplasty (TJA). The area deprivation index (ADI) is a scale that ranks (zero to 100) neighborhoods by increasing socioeconomic disadvantage and accounts for median income, housing type, and family structure. We sought to examine the potential differences between high (national median ADI = 47) and low ADI among TJA recipients at a single institution. Specifically, we assessed: (1) 30-day emergency department visits/readmissions; (2) 90-day and 1-year revisions; as well as (3) medical and surgical complications. METHODS: A consecutive series of primary TJAs from September 21, 2015, through December 29, 2021, at a tertiary healthcare system were reviewed. A total of 3,024 patients who had complete ADI data were included. Patients were divided into groups below the national median ADI of 47 (n = 1,896) and above (n = 1,128). Multivariable regressions to determine independent risk factors accounting for ADI, race, age, sex, American Society of Anesthesiologists Classification grade, body mass index, diabetes, congestive heart failure (CHF), chronic obstructive pulmonary disease, hypertension, chronic kidney disease, alcohol abuse, substance abuse, and tobacco use. The primary outcomes of interest include evaluation of the independent association of ADI with total postoperative complications (at 30 days, 90 days, and 1 year) after adjusting for multiple relevant cofactors. RESULTS: After adjusting for multiple relevant cofactors, at 90 days, ADI > 47 (OR, 1.36, 95% CI 1.00-1.83, P = 0.04), men versus women (OR, 0.73, 95% CI 0.54-0.99, P = 0.039), and CHF (OR, 1.90, 95% CI 1.18-3.06, P = 0.009) were independently associated with increased total complications. The ADI was not associated with increased total complications at 30 days or 1-year (All P > 0.05). CONCLUSION: Our findings of higher complications of the ADI > 47 cohort at 90 days, reaffirm the complex relationship between ADI, patient demographics, and additional socioeconomic parameters that may influence postoperative outcomes and complications after TJA. This study utilizing ADI demonstrates potential areas of intervention and further investigation for assessing arthroplasty outcomes.

Postoperative Opioid Dependence in Patients Undergoing Either Total or Reverse Shoulder Arthroplasty for Proximal Humerus Fracture Fixation.

INTRODUCTION: In elderly patients who have proximal humerus fractures, treatment commonly involves total shoulder arthroplasty (TSA) or reverse shoulder arthroplasty (RSA). Following these procedures, patients often require opioids for postoperative analgesia. This common scenario is of clinical and societal importance, as increased postoperative opioid usage has been shown to worsen outcomes and increase the likelihood for dependence. We aimed to compare postoperative opioid use in patients undergoing either TSA or RSA for fixation of their proximal humerus fracture. Specifically, we assessed: (1) postoperative opioid use at two, four, six, eight, and greater than eight weeks postoperatively; (2) aseptic revision rates at 90-days, one year, and two years postoperatively; and (3) periprosthetic joint infection (PJI) rates at 90-days, one year, and two years postoperatively between patients undergoing TSA or RSA for the surgical management of their proximal humerus fractures. MATERIALS AND METHODS: For this review, we queried a national all-payer database from October 1, 2015 to October 31, 2020 (n=1.5 million) for all patients who had a "proximal humerus fracture" diagnosis who underwent either TSA or RSA. There were two cohorts: patients undergoing TSA (n=731) and patients undergoing RSA (n=731). Bivariate Chi-square analyses. RESULTS: We found no differences (p>0.05) in opioid use postoperatively in patients undergoing RSA for proximal humerus management compared to patients undergoing TSA after two weeks. There was not a significant difference in aseptic revision or PJI rates between the two cohorts (all p>0.05). CONCLUSION: The evidence comparing opioid use in patients undergoing either TSA or RSA for proximal humerus fracture fixation is lacking. Our study specifically showed no differences in opioid use postoperatively in patients undergoing RSA for proximal humerus management compared to patients undergoing TSA.

Low Wear at 10-Year Follow-Up of a Second-Generation Highly Cross-Linked Polyethylene in Total Hip Arthroplasty.

BACKGROUND: Characterizations and factors influencing longer term performance of second-generation sequentially irradiated and annealed highly cross-linked polyethylene (HXLPE) are lacking. We evaluated patients who underwent total hip arthroplasty with HXLPE at mean 10-year follow-up for (1) linear and volumetric wear rates, (2) patient and implant characteristics, (3) implant survivorships, and (4) functional scores. METHODS: We evaluated 130 hips (110 patients) that received HXLPE acetabular liners at a single center. The mean age was 56 years (range, 20-79 years), with a mean follow-up of 10 years (range, 8-15). Radiographic linear (millimeters/year) and volumetric (cubic millimeters/year) wear rates were quantified using radiographic analysis. Survivorship was assessed by all-cause and wear-related revision rates. Functional outcomes were assessed by Short Form 12 and modified Harris Hip Scores. RESULTS: The mean linear wear rate was 0.02 ± 0.03 mm/y, and the mean volumetric wear rate was 12.6 ± 5.3 mm3/y. Younger age had higher volumetric wear (total and yearly, P = .01). Increasing body mass index trended toward higher total and yearly linear (both, P ≤ .09) and volumetric wear (both, P ≤ .07). Ten patients required revisions, with an all-cause survivorship of 92% and a wear survivorship of 100%. The mean modified Harris Hip Scores was 84, and the mean Short Form 12 scores were 46 (physical) and 55 (mental). CONCLUSION: We observed low linear and volumetric wear rates for HXLPE at 10-year mean follow-up. Younger age and higher body mass index at the time of surgery may be important patient characteristics influencing long-term wear. These results illustrate the potential for this second-generation HXLPE to be an appropriate long-term total hip arthroplasty interface.

Social Determinants of Health in Total Hip Arthroplasty: Are They Associated With Costs, Lengths of Stay, and Patient Reported Outcomes?

BACKGROUND: Social determinants of health (SDOH) may play a larger role in predicting patient outcomes as outpatient total hip arthroplasty (THA) expands. We specifically examined the association between SDOH and patient metrics (demographics and comorbidities) for: (1) 30-day post-discharge costs of care; (2) lengths of stay (LOS); and (3) patient-reported outcomes (Hip Disability and Osteoarthritis Outcomes Score for Joints Replacement (HOOS JR)). METHODS: Medicare patients who underwent primary THA between 2018 and 2019 were identified. Those who had complete social determinant data were included (n = 136). Data elements were drawn from institutional, regional, and government databases, as well as the Social Vulnerability Index (SVI). Multiple regression analyses were performed to determine SDOH and baseline comorbidities associations with costs, LOS, and HOOS JR scores. RESULTS: Various SDOH factors were associated with higher 30-day costs, including residing in a food desert ($53,695 ± 15,485; P < .001) and the following SVI themes: 'Minority Status and Language' ($24,075 ± 9845; P = .01) and 'Housing and Transportation' ($16,190 ± 8501; P = .06), although the latter did not meet statistical significance. Baseline depression was associated with longer LOS (P = .02), while none of the other SDOH or patient metrics affected LOS. No relationships were observed between SDOH and HOOS JR changes from baseline. CONCLUSION: Patients who live in food deserts and have minority status had higher costs of care after primary THA. Poor housing and transportation may also increase costs, albeit insignificantly. These results highlight the utility of assessing SDOH-related risk factors to optimize post-operative outcomes, with potential implications for bundled care.

flasher, a novel mutation in a glucosinolate modifying enzyme, conditions changes in plant architecture and hormone homeostasis.

Meristem function is underpinned by numerous genes that affect hormone levels, ultimately controlling phyllotaxy, the transition to flowering and general growth properties. Class I KNOX genes are major contributors to this process, promoting cytokinin biosynthesis but repressing gibberellin production to condition a replication competent state. We identified a suppressor mutant of the KNOX1 mutant brevipedicellus (bp) that we termed flasher (fsh), which promotes stem and pedicel elongation, suppresses early senescence, and negatively affects reproductive development. Map-based cloning and complementation tests revealed that fsh is due to an E40K change in the flavin monooxygenase GS-OX5, a gene encoding a glucosinolate (GSL) modifying enzyme. In vitro enzymatic assays revealed that fsh poorly converts substrate to product, yet the levels of several GSLs are higher in the suppressor line, implicating FSH in feedback control of GSL flux. FSH is expressed predominantly in the vasculature in patterns that do not significantly overlap those of BP, implying a non-cell autonomous mode of meristem control via one or more GSL metabolites. Hormone analyses revealed that cytokinin levels are low in bp, but fsh restores cytokinin levels to near normal by activating cytokinin biosynthesis genes. In addition, jasmonate levels in the fsh suppressor are significantly lower than in bp, which is likely due to elevated expression of JA inactivating genes. These observations suggest the involvement of the GSL pathway in generating one or more negative effectors of growth that influence inflorescence architecture and fecundity by altering the balance of hormonal regulators.

The Drosophila foraging gene plays a vital role at the start of metamorphosis for subsequent adult emergence.

The foraging (for) gene has been extensively studied in many species for its functions in development, physiology, and behavior. It is common for genes that influence behavior and development to be essential genes, and for has been found to be an essential gene in both fruit flies and mammals, with for mutants dying before reaching the adult stage. However, the biological process underlying the lethality associated with this gene is not known. Here, we show that in Drosophila melanogaster, some but not all gene products of for are essential for survival. Specifically, we show that promoter 3 of for, but not promoters 1, 2, and 4 are required for survival past pupal stage. We use full and partial genetic deletions of for, and temperature-restricted knock-down of the gene to further investigate the stage of lethality. While deletion analysis shows that flies lacking for die at the end of pupal development, as pharate adults, temperature-restricted knock-down shows that for is only required at the start of pupal development, for normal adult emergence (AE) and viability. We further show that the inability of these mutants to emerge from their pupal cases is linked to deficiencies in emergence behaviors, caused by a possible energy deficiency, and finally, that the lethality of for mutants seems to be linked to protein isoform P3, transcribed from for promoter 3.

THAs Performed Within 6 Months of Clostridioides difficile Infection Are Associated with Increased Risk of 90-Day Complications.

BACKGROUND: Clostridioides difficile infection (CDI) may be a surrogate for poor patient health. As such, a history of CDI before THA may be used to identify patients at higher risk for postoperative CDI and complications after THA. Investigations into the associations between CDI before THA and postoperative CDI and complications are lacking. QUESTIONS/PURPOSES: We compared the (1) frequency and potential risk factors for CDI after THA, (2) the frequency of 90-day complications after THA in patients with and without a history of CDI, and (3) the length of stay and frequency of readmissions in patients experiencing CDIs more than 6 months before THA, patients experiencing CDIs in the 6 months before THA, and patients without a history of CDI. METHODS: Patients undergoing primary THA from 2010 to 2019 were identified in the PearlDiver database using ICD and Current Procedural Terminology codes (n = 714,185). This analysis included Medicare, Medicaid, and private insurance claims across the United States with the ability to perform longitudinal and costs analysis using large patient samples to improve generalizability and reduce error rates. Patients with a history of CDI before THA (n = 5196) were stratified into two groups: those with CDIs that occurred more than 6 months before THA (n = 4003, median 2.2 years [interquartile range 1.2 to 3.6]) and those experiencing CDIs within the 6 months before THA (n = 1193). These patients were compared with the remaining 708,989 patients without a history of CDI before THA. Multivariable logistic regression was used to evaluate the association of risk factors and incidence of 90-day postoperative CDI in patients with a history of CDI. Variables such as antibiotic use, proton pump inhibitor use, chemotherapy, and inflammatory bowel disease were included in the models. Chi-square and unadjusted odds ratios with 95% confidence intervals were used to compare complication frequencies. A Bonferroni correction adjusted the p value significance threshold to < 0.003. RESULTS: Prior CDI during either timespan was associated with higher unadjusted odds for postoperative CDI (CDI > 6 months before THA: OR 8.44 [95% CI 6.95 to 10.14]; p < 0.001; CDI ≤ 6 months before THA: OR 49.92 [95% CI 42.26 to 58.54]; p < 0.001). None of the risk factors included in the regression were associated with increased odds for postoperative CDI in patients with preoperative history of CDI. Patients with a history of CDI before THA were associated with higher unadjusted odds for every 90-day complication compared with patients without a history of CDI before THA. CDI during either timespan was associated with longer lengths of stay (no CDI before THA: 3.8 days; CDI > 6 months before THA: 4.5 days; CDI ≤ 6 months before THA: 5.3 days; p < 0.001) and 90-day readmissions (CDI > 6 months before THA: OR 2.21 [95% CI 1.98 to 2.47]; p < 0.001; CDI ≤ 6 months before THA: OR 3.39 [95% CI 2.85 to 4.02]; p < 0.001). CONCLUSION: Having CDI before THA was associated with higher odds of postoperative CDI compared with patients without a history of CDI. A history of CDI within the 6 months before THA was associated with the greatest odds for postoperative complications and readmissions. Providers should strongly consider delaying THA until 6 months after CDI, if possible, to provide adequate time for patient recovery and eradication of infection. LEVEL OF EVIDENCE: Level III, therapeutic study.

How Does Conversion Total Hip Arthroplasty Compare to Primary?

BACKGROUND: Recent institutional evidence suggests that conversion total hip arthroplasty (THA) incurs higher complication rates and costs when compared to primary THA. These findings contrast with the current reimbursement system as conversion and primary THAs are classified under the same diagnosis-related group. Thus, a national all-payer database was utilized to compare complication rates up to 2 years, 30-day readmission rates, and 90-day costs between conversion THA and matched primary THA patients. METHODS: A retrospective review of the PearlDiver database between 2010 and second quarter of 2018 was performed using Current Procedural Terminology (CPT) codes to compare conversion THA (CPT 27132) to primary THA (CPT 27130). Patients were matched at a 1:3 ratio based on age, gender, Charlson Comorbidity Index, body mass index, tobacco use, and diabetes (conversion = 8369; primary = 25,081 patients). RESULTS: Conversion THA had higher rates of periprosthetic joint infections (conversion: 7.7% vs primary: 1.4%), hip dislocations (4.5% vs 2.0%), blood transfusions (2.0% vs 1.0%), mechanical complications (5.5% vs 1.0%), and revision surgeries (4.0% vs 1.5%) (P < .001 for all) by 90 days. The 30-day readmission rate for conversion THA was significantly higher compared to the primary group (7.3% vs 3.3%) (P < .001). Median cost at 90 days for conversion THA was significantly higher compared to primary THA ($18,800 vs $13,611, P < .001). CONCLUSION: This study revealed increased complication rates, revisions, readmissions, and costs among conversion THA patients compared to matched primary THA patients. These results support the reclassification of conversion into a diagnosis-related group separate from primary THA.

Osteoarthritis and Osteonecrosis in Total Hip Arthroplasty: 90-Day Postoperative Costs and Outcomes.

BACKGROUND: Two common diagnoses for patients undergoing total hip arthroplasty (THA) are osteoarthritis (OA) and osteonecrosis (ON), pathologically different diseases that affect postoperative complication rates. The underlying pathology of ON may predispose patients to a higher rate of certain complications. Previous research has linked ON with higher mortality and revisions, but a comparison of costs and complication rates may help elucidate further risks. This study reports 90-day costs, lengths of stay (LOS), readmission rates, and complication rates between patients undergoing THA for OA and ON. METHODS: The Nationwide Readmissions Database was retrospectively reviewed for primary THAs, with 90-day readmissions assessed from the index procedure. Patients diagnosed with OA (n = 1,577,991) and ON (n = 55,034) were identified. Costs, LOS, and any readmission within 90 days for complications were recorded and analyzed with the chi-square and t-tests. RESULTS: Patients with ON had higher 90-day costs ($20,110.80 vs. 22,462.79, P < .01) and longer average LOS (3.48 vs. 4.49 days, P < .01). Readmission rates within 90 days of index THA were significantly higher among patients with ON (7.7% vs. 13.1%, P < .01). Patients with OA had a lower incidence of 90-day overall complications (4.1 vs. 6.4%, P < .01). CONCLUSIONS: Patients undergoing THA for ON incur higher readmission-related costs and complication rates. Understanding the predisposing factors for increased complications in ON may improve patient outcomes.

Front-of-neck airway rescue with impalpable anatomy during a simulated cannot intubate, cannot oxygenate scenario: scalpel-finger-cannula versus scalpel-finger-bougie in a sheep model.

BACKGROUND: Front-of-neck airway rescue in a cannot intubate, cannot oxygenate (CICO) scenario with impalpable anatomy is particularly challenging. Several techniques have been described based on a midline vertical neck incision with subsequent finger dissection, followed by either a cannula or scalpel puncture of the now palpated airway. We explored whether the speed of rescue oxygenation differs between these techniques. METHODS: In a high-fidelity simulation of a CICO scenario in anaesthetised Merino sheep with impalpable front-of-neck anatomy, 35 consecutive eligible participants undergoing airway training performed scalpel-finger-cannula and scalpel-finger-bougie in a random order. The primary outcome was time from airway palpation to first oxygen delivery. Data, were analysed with Cox proportional hazards. RESULTS: Scalpel-finger-cannula was associated with shorter time to first oxygen delivery on univariate (hazard ratio [HR]=11.37; 95% confidence interval [CI], 5.14-25.13; P<0.001) and multivariate (HR=8.87; 95% CI, 4.31-18.18; P<0.001) analyses. In the multivariable model, consultant grade was also associated with quicker first oxygen delivery compared with registrar grade (HR=3.28; 95% CI, 1.36-7.95; P=0.008). With scalpel-finger-cannula, successful oxygen delivery within 3 min of CICO declaration and ≤2 attempts was more frequent; 97% vs 63%, P<0.001. In analyses of successful cases only, scalpel-finger-cannula resulted in earlier improvement in arterial oxygen saturations (-25 s; 95% CI, -35 to -15; P<0.001), but a longer time to first capnography reading (+89 s; 95% CI, 69 to 110; P<0.001). No major complications occurred in either arm. CONCLUSIONS: The scalpel-finger-cannula technique was associated with superior oxygen delivery performance during a simulated CICO scenario in sheep with impalpable front-of-neck anatomy.

Effect of Apneic Oxygenation on Tracheal Oxygen Levels, Tracheal Pressure, and Carbon Dioxide Accumulation: A Randomized, Controlled Trial of Buccal Oxygen Administration.

BACKGROUND: Apneic oxygenation via the oral route using a buccal device extends the safe apnea time in most but not all obese patients. Apneic oxygenation techniques are most effective when tracheal oxygen concentrations are maintained >90%. It remains unclear whether buccal oxygen administration consistently achieves this goal and whether significant risks of hypercarbia or barotrauma exist. METHODS: We conducted a randomized trial of buccal or sham oxygenation in healthy, nonobese patients (n = 20), using prolonged laryngoscopy to maintain apnea with a patent airway until arterial oxygen saturation (SpO2) dropped <95% or 750 seconds elapsed. Tracheal oxygen concentration, tracheal pressure, and transcutaneous carbon dioxide (CO2) were measured throughout. The primary outcome was maintenance of a tracheal oxygen concentration >90% during apnea. RESULTS: Buccal patients were more likely to achieve the primary outcome (P < .0001), had higher tracheal oxygen concentrations throughout apnea (mean difference, 65.9%; 95% confidence interval [CI], 62.6%-69.3%; P < .0001), and had a prolonged median (interquartile range) apnea time with SpO2 >94%; 750 seconds (750-750 seconds) vs 447 seconds (405-525 seconds); P < .001. One patient desaturated to SpO2 <95% despite 100% tracheal oxygen. Mean tracheal pressures were low in the buccal (0.21 cm·H2O; SD = 0.39) and sham (0.56 cm·H2O; SD = 1.25) arms; mean difference, -0.35 cm·H2O; 95% CI, 1.22-0.53; P = .41. CO2 accumulation during early apnea before any study end points were reached was linear and marginally faster in the buccal arm (3.16 vs 2.82 mm Hg/min; mean difference, 0.34; 95% CI, 0.30-0.38; P < .001). Prolonged apnea in the buccal arm revealed nonlinear CO2 accumulation that declined over time and averaged 2.22 mm Hg/min (95% CI, 2.21-2.23). CONCLUSIONS: Buccal oxygen administration reliably maintains high tracheal oxygen concentrations, but early arterial desaturation can still occur through mechanisms other than device failure. Whereas the risk of hypercarbia is similar to that observed with other approaches, the risk of barotrauma is negligible. Continuous measurement of advanced physiological parameters is feasible in an apneic oxygenation trial and can assist with device evaluation.

Photobiomodulation therapy as a tool to prevent hamstring strain injuries by reducing soccer-induced fatigue on hamstring muscles.

Muscle fatigue is a potential risk factor for hamstring strain injuries in soccer players. The aim of this study was to verify the effect of photobiomodulation therapy (PBMT) on the hamstrings' muscle fatigue of soccer players during a simulated match. Twelve male amateur soccer players (~ 25 years) participated in this randomized, crossover, double-blinded, placebo-controlled trial. The volunteers were evaluated in two sessions, with a minimum 7-day interval. At each session, volunteers received either PBMT (300 J per thigh) or placebo treatment on the hamstrings prior to the simulated soccer match. Muscle strength and functional capacity were evaluated through isokinetic dynamometry and countermovement jump (CMJ) tests, respectively, before and immediately after the simulated soccer match. Players had lower reductions on hamstring eccentric peak torque [4.85% (ES = 0.31) vs. 8.72% (ES = 0.50)], hamstring-to-quadriceps torque ratio [3.60% (ES = 0.24) vs. 7.75% (ES = 0.50)], and CMJ height [1.77% (ES = 0.09) vs. 5.47% (ES = 0.32)] when treated with PBMT compared to placebo. Magnitude-based inference supports that PBMT promoted 75%, 69%, and 53% chances for beneficial effects on hamstring eccentric peak torque, hamstring-to-quadriceps torque ratio, and CMJ height, respectively, compared to placebo treatment. In conclusion, PBMT applied before a simulated soccer match proved to be effective in attenuating the hamstrings' muscle fatigue. These findings support PBMT as a promising tool to prevent hamstring strain injury in soccer players.

Photobiomodulation therapy (PBMT) on acute pain and inflammation in patients who underwent total hip arthroplasty-a randomized, triple-blind, placebo-controlled clinical trial.

When conservative treatments fail, hip osteoarthritis (OA), a chronic degenerative disease characterized by cartilage wear, progressive joint deformity, and loss of function, can result in the need for a total hip arthroplasty (THA). Surgical procedures induced tissue trauma and incite an immune response. Photobiomodulation therapy (PBMt) using low-level laser therapy (LLLT) and/or light-emitting diode therapy (LEDT) has proven effective in tissue repair by modulating the inflammatory process and promoting pain relief. Therefore, the aim of this study was to analyze the immediate effect of PBMt on inflammation and pain of patients undergoing total hip arthroplasty. The study consisted of 18 post-surgical hip arthroplasty patients divided into two groups (n = 9 each) placebo and active PBMt who received one of the treatments in a period from 8 to 12 h following THA surgery. PBMt (active or placebo) was applied using a device consisting of nine diodes (one super-pulsed laser of 905 nm, four infrared LEDs of 875 nm, and four red LEDs 640 nm, 40.3 J per point) applied to 5 points along the incision. Visual analog scale (VAS) and blood samples for analysis of the levels of the cytokines TNF-α, IL-6, and IL-8 were recorded before and after PBMt application. The values for the visual analog scale as well as those in the analysis of TNF-α and IL-8 serum levels decreased in the active PBMt group compared to placebo-control group (p < 0.05). No decrease was observed for IL-6 levels. We conclude that PBMt is effective in decreasing pain intensity and post-surgery inflammation in patients receiving total hip arthroplasty.

Career Development and Learning Pathways of Paralympic Coaches With a Disability.

The purpose of this study was to gain an understanding of the career development and learning pathways of Paralympic head coaches who previously competed as Paralympic athletes. Each coach participated in a semistructured interview. A thematic analysis of the data revealed three higher order themes, which were called becoming a coach, learning to coach, and lifelong learning and teaching. Across these themes, participants discussed interactions with other coaches and athletes with a disability, learning from mentors and coaching clinics, as well as limited formal educational opportunities they experienced transitioning from athlete to head coach. The findings revealed that they acquired most of their knowledge from a combination of knowledge gained as athletes and informal sources, including trial and error. They also stressed the need for enhanced recruiting of parasport coaches and parasport coach education opportunities that would enhance programs for athletes with physical disabilities, from grassroots to Paralympic levels.

Photobiomodulation therapy (PBMT) and/or cryotherapy in skeletal muscle restitution, what is better? A randomized, double-blinded, placebo-controlled clinical trial.

Cryotherapy for post-exercise recovery remains widely used despite the lack of quality evidence. Photobiomodulation therapy (PBMT) studies (with both low-level laser therapy and light-emitting diode therapy) have demonstrated positive scientific evidence to suggest its use. The study aims to evaluate PBMT and cryotherapy as a single or combined treatment on skeletal muscle recovery after eccentric contractions of knee extensors. Fifty healthy male volunteers were recruited and randomized into five groups (PBMT, cryotherapy, cryotherapy + PBMT, PMBT + cryotherapy, or placebo) for a randomized, double-blinded, placebo-controlled trial that evaluated exercise performance (maximum voluntary contraction (MVC)), delayed onset muscle soreness (DOMS), and muscle damage (creatine kinase (CK)). Assessments were performed at baseline; immediately after; and at 1, 24, 48, 72, and 96 h. Comparator treatments was performed 3 min after exercise and repeated at 24, 48, and 72 h. PBMT was applied employing a cordless, portable GameDay™ device (combination of 905 nm super-pulsed laser and 875- and 640-nm light-emitting diodes (LEDs); manufactured by Multi Radiance Medical™, Solon - OH, USA), and cryotherapy by flexible rubber ice packs. PBMT alone was optimal for post-exercise recovery with improved MVC, decreased DOMS, and CK activity (p < 0.05) from 24 to 96 h compared to placebo, cryotherapy, and cryotherapy + PBMT. In the PBMT + cryotherapy group, the effect of PBMT was decreased (p > 0.05) but demonstrated significant improvement in MVC, decreased DOMS, and CK activity (p < 0.05). Cryotherapy as single treatment and cryotherapy + PBMT were similar to placebo (p > 0.05). We conclude that PBMT used as single treatment is the best modality for enhancement of post-exercise restitution, leading to complete recovery to baseline levels from 24 h after high-intensity eccentric contractions.

Chromosome fragile sites in Arabidopsis harbor matrix attachment regions that may be associated with ancestral chromosome rearrangement events.

Mutations in the BREVIPEDICELLUS (BP) gene of Arabidopsis thaliana condition a pleiotropic phenotype featuring defects in internode elongation, the homeotic conversion of internode to node tissue, and downward pointing flowers and pedicels. We have characterized five mutant alleles of BP, generated by EMS, fast neutrons, x-rays, and aberrant T-DNA insertion events. Curiously, all of these mutagens resulted in large deletions that range from 140 kbp to over 900 kbp just south of the centromere of chromosome 4. The breakpoints of these mutants were identified by employing inverse PCR and DNA sequencing. The south breakpoints of all alleles cluster in BAC T12G13, while the north breakpoint locations are scattered. With the exception of a microhomology at the bp-5 breakpoint, there is no homology in the junction regions, suggesting that double-stranded breaks are repaired via non-homologous end joining. Southwestern blotting demonstrated the presence of nuclear matrix binding sites in the south breakpoint cluster (SBC), which is A/T rich and possesses a variety of repeat sequences. In situ hybridization on pachytene chromosome spreads complemented the molecular analyses and revealed heretofore unrecognized structural variation between the Columbia and Landsberg erecta genomes. Data mining was employed to localize other large deletions around the HY4 locus to the SBC region and to show that chromatin modifications in the region shift from a heterochromatic to euchromatic profile. Comparisons between the BP/HY4 regions of A. lyrata and A. thaliana revealed that several chromosome rearrangement events have occurred during the evolution of these two genomes. Collectively, the features of the region are strikingly similar to the features of characterized metazoan chromosome fragile sites, some of which are associated with karyotype evolution.

The thermal impact of phototherapy with concurrent super-pulsed lasers and red and infrared LEDs on human skin.

From the very first reports describing the method of action of phototherapy, the effects have been considered to be the result of photochemical and photophysical interactions between the absorbed photons and tissue and not related to secondary changes in tissue or skin temperature. However, thermal effects have been recently reported in dark pigmented skin when irradiated with single wavelengths of 810 and 904 nm of low-level laser therapy (LLLT) devices even with doses that do not exceed those recommended by the World Association of Laser Therapy (WALT). The aim of this study was to evaluate the thermal impact during the concurrent use of pulsed red and infrared LEDs and super-pulsed lasers when applied to light, medium, and dark pigmented human skin with doses typically seen in clinical practice. The study evaluated the skin temperature of 42 healthy volunteers (males and females 18 years or older, who presented different pigmentations, stratified according to Von Luschan's chromatic scale) via the use of a thermographic camera. Active irradiation was performed with using the multi-diode phototherapy cluster containing four 905-nm super-pulsed laser diodes (frequency set to 250 Hz), four 875-nm infrared-emitting diodes, and four 640-nm LEDs (manufactured by Multi Radiance Medical™, Solon, OH, USA). Each of the four doses were tested on each subject: placebo, 0 J (60 s); 10 J (76 s); 30 J (228 s); and 50 J (380 s). Data were collected during the last 5 s of each dose of irradiation and continued for 1 min after the end of each irradiation. No significant skin temperature increases were observed among the different skin color groups (p > 0.05), age groups (p > 0.05), or gender groups (p > 0.05). Our results indicate that the concurrent use of super-pulsed lasers and pulsed red and infrared LEDs can be utilized in patients with all types of skin pigmentation without concern over safety or excessive tissue heating. Additionally, the doses and device utilized in present study have demonstrated positive outcomes in prior clinical trials. Therefore, it can be concluded that the effects seen by the concurrent use of multiple wavelengths and light sources were the result of desirable photobiomodulation effect and not related to thermal influence.

Adjunctive use of combination of super-pulsed laser and light-emitting diodes phototherapy on nonspecific knee pain: double-blinded randomized placebo-controlled trial.

Phototherapy with low-level laser therapy (LLLT) and light-emitting diode therapy (LEDT) has arisen as an interesting alternative to drugs in treatments of musculoskeletal disorders. However, there is a lack of studies investigating the effects of combined use of different wavelengths from different light sources like lasers and light-emitting diodes (LEDs) in skeletal muscle disorders. With this perspective in mind, this study aimed to investigate the effects of phototherapy with combination of different light sources on nonspecific knee pain. It was performed a randomized, placebo-controlled, double-blinded clinical trial. Eighty-six patients rated 30 or greater on the pain visual analogue scale (VAS) were recruited and included in study. Patients of LLLT group received 12 treatments with active phototherapy (with 905 nm super-pulsed laser and 875 and 640 nm LEDs, Manufactured by Multi Radiance Medical, Solon, OH, USA) and conventional treatment (physical therapy or chiropractic care), and patients of placebo group were treated at same way but with placebo phototherapy device. Pain assessments (VAS) were performed at baseline, 4th, 7th, and 10th treatments, after the completion of treatments and at 1-month follow-up visit. Quality of life assessments (SF-36®) were performed at baseline, after the completion of treatments and at 1-month follow-up visit. Our results demonstrate that phototherapy significantly decreased pain (p < 0.05) from 10th treatment to follow-up assessments and significantly improved (p < 0.05) SF-36® physical component summary at posttreatments and follow-up assessments compared to placebo. We conclude that combination of super-pulsed laser, red and infrared LEDs is effective to decrease pain and improve quality of life in patients with knee pain.

C. Difficile Infection within 6 Months before TKA Is Associated with Increased Short-Term Complications.

A history of Clostridium difficile infection (CDI) before total knee arthroplasty (TKA) may be a marker for poor patient health and could be used to identify patients with higher risks for complications after TKA. We compared the frequency of 90-day postoperative CDI, complications, readmissions, and associated risk factors in (1) patients experiencing CDIs more than 6 months before TKA, (2) patients experiencing CDIs in the 6 months before TKA, and (3) patients without a history of CDI. We identified patients who underwent primary TKAs from 2010 to 2019 and had a history of CDI before TKA (n = 7,195) using a national, all-payer database. Patients were stratified into two groups: those with CDIs > 6 months before TKA (n = 6,027) and those experiencing CDIs ≤ 6 months before TKA (n = 1,168). These patients were compared with the remaining 1.4 million patients without a history of CDI before TKA. Chi-square and unadjusted odds ratios (ORs) with 95% confidence intervals (CI) were used to compare complication frequencies. Prior CDI during either timespan was associated with higher unadjusted odds for postoperative CDI (CDI > 6 months before TKA: OR 8.03 [95% CI 6.68-9.63]; p < 0.001; CDI ≤ 6 months before TKA: OR 59.05 [95% CI 49.66-70.21]; p < 0.001). Patients with a history of CDI before TKA were associated with higher unadjusted odds for 90-day complications and readmission compared with patients without a history of CDI before TKA. Other comorbidities and health metrics were not found to be associated with postoperative CDI (i.e., age, obesity, smoking, antibiotic use, etc.). CONCLUSION: CDI before TKA was associated with higher odds of postoperative CDI compared with patients without a history of CDI. CDI ≤ 6 months before TKA was associated with the highest odds for postoperative complications and readmissions. Providers should consider delaying TKA after CDI, if possible, to allow for patient recovery and eradication of infection.