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Seabirds have been touted as excellent bioindicators of mercury pollution. We utilised grey-faced petrel (Pterodroma gouldi) feathers to assess interannual differences in total mercury (THg) concentrations in adults (2020-2021) and chicks (2019-2021) breeding in the Auckland region of New Zealand. For adults, we also correlated feather THg with bird age (3-37+ years) and breeding outcome (i.e., Non breeder, Egg failed, Chick reared) recorded for that season i.e., 2020 and 2021. Interannual differences in chick feather THg were matched with bulk stable isotopes (δ13C, δ15N) to map the influence of adult foraging behaviour on chick feather THg values. Adult feather THg levels were similar across the years investigated i.e., mean⯱â¯S.D. 38.2⯱â¯12.8 (2020), and 39.5⯱â¯14.7 (2021) ug g-1 (some of the highest THg values recorded for seabirds). A slight, but significant decrease in THg accumulation was evident as age increased but feather THg had no significant influence on breeding outcome. Interannual differences in chick feather THg concentrations were 7.78⯱â¯1.6 (2019), 4.23⯱â¯1.45 (2020) and 6.97⯱â¯4.41 (2021) µg g-1, (pâ¯<â¯0.01); and correlated with a significantly lower δ13C value i.e., -17.2⯱â¯0.4⯠(2019), -17.8⯱â¯0.3⯠(2020) and -17.6⯱â¯0.2⯠(2021). This suggests that the lower feather THg values in 2020 chicks resulted from more oceanic, rather than shelf-edge, prey being consumed by chicks that year. Values of δ15N in chick feathers remained consistent among years i.e., 15.2⯱â¯1.2⯠(2019), 15.2⯱â¯0.2⯠(2020) and 15.3⯠(± 0.4). Due to these interannual differences, we recommend using grey-faced petrel chicks to monitor Hg pollution over adults. Chicks are also subject to cultural harvests by Maori communities, offering partnership opportunities to generate mutually beneficial information streams for Maori communities and scientists alike.
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PURPOSE: The standard of care for burned patients experiencing hyperglycemia associated with the hypermetabolic response is insulin therapy. Insulin treatment predisposes burn patients to hypoglycemia, which increases morbidity and mortality. Metformin has been suggested as an alternative to insulin therapy for glycemic control in burn patients given its safety profile, but further research is warranted. This study investigated whether metformin use in burn patients is associated with improved glycemic control and morbidity/mortality outcomes compared to insulin use alone. MATERIALS AND METHODS: Using the TriNetX database, we conducted a retrospective study of burned patients who were administered insulin, metformin, or both within one week of injury. Demographic, comorbidity, and burn severity information were collected. Patients were categorized by treatment type, propensity score-matched, and compared for the following outcomes within 3 months: hyperglycemia, hypoglycemia, sepsis, lactic acidosis, and death. Statistical significance was set a priori at p ≤ 0.05. RESULTS: The insulin cohort was at increased risk for all outcomes (all p < 0.0001) compared to the metformin cohort, and an increased risk for sepsis, lactic acidosis, and death (all p ≤ 0.0002) compared to the insulin/metformin combination cohort. When compared to the metformin cohort, the combination cohort was at increased risk for all outcomes (all p ≤ 0.0107) except death. CONCLUSIONS: Treatment with metformin after burn is associated with a reduced risk of morbidity and mortality compared to insulin. The combination of insulin and metformin is no more effective in reducing the risk of hyperglycemia and hypoglycemia than insulin alone but is less effective than metformin alone.
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Mental health literacy (MHL) was introduced 25 years ago as knowledge and beliefs about mental disorders which aid in their recognition, management, or prevention. This scoping review mapped the peer-reviewed literature to assess characteristics of secondary school-based surveys in school-attending youth and explore components of school-based programs for fostering MHL in this population. The search was performed following the method for scoping reviews by the Joanna Briggs Institute (JBI). Searches were conducted in four scientific databases with no time limit, although all sources had to be written in English. Primary studies (N = 44) provided insight into MHL surveys and programs for school-attending youth across 6 continents. Studies reported that most youth experience moderate or low MHL prior to program participation. School-based MHL programs are relatively unified in their definition and measures of MHL, using closed-ended scales, vignettes, or a combination of the two to measure youth MHL. However, before developing additional interventions, steps should be taken to address areas of weakness in current programming, such as the lack of a standardized tool for assessing MHL levels. Future research could assess the feasibility of developing and implementing a standard measurement protocol, with educator perspectives on integrating MHL efforts into the classroom. Identifying the base levels of MHL amongst school-attending youth promotes the development of targeted programs and reviewing the alignment with program components would allow researchers to build on what works, alter what does not, and come away with new ways to approach these complex challenges, ultimately advancing knowledge of MHL and improving levels of MHL.
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INTRODUCTION: Aerosol mitigation equipment implemented due to COVID-19 has increased noise levels in the operating room (OR) during otolaryngological procedures. Intraoperative sound levels may potentially place personnel at risk for occupational hearing loss. This study hypothesized that cumulative intraoperative noise exposures with aerosol mitigation equipment exceed recommended occupational noise exposure levels. METHODS: Sound levels generated by the surgical smoke evacuator (SSE) during adenotonsillectomy were measured using a sound level meter and compared to surgery without SSE. RESULTS: Thirteen adenotonsillectomy surgeries were recorded. Mean sound levels with the SSE were greater than the control (72 ± 3 A-weighted decibels (dBA) vs. 68 ± 2 dBA; p=0.015). Maximum noise levels during surgery with SSE reached 82 ± 3 dBA. CONCLUSION: Surgeons performing adenotonsillectomy with aerosol mitigation equipment are exposed to significant noise levels. Intraoperative sound levels exceeded international standards for work requiring concentration. Innovation is needed to reduce cumulative OR noise exposures.
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Objective: This study aims to investigate potential differences in surgical subspecialty match rates between medical schools with and without elective rotations in the respective surgical subspecialties. Design: Data on duration of surgical rotations were retrieved from each school's public website. Fisher exact tests were performed to identify any statistically significant differences in surgical specialty match rates by allopathic versus osteopathic and elective clinical exposure. A linear regression was performed to determine the correlation between number of surgical electives offered and proportion of students matching in any surgical subspecialty. Results: The number of surgical electives offered by allopathic medical schools positively correlated with the proportion of students matching in any surgical specialty (R2 = 0.038, p = 0.018). Elective rotations in surgical subspecialties were associated with higher match rates in ophthalmology (OR 1.864, 95 % CI 1.196, 3.059, p < 0.01) and plastic surgery (OR 2.543, CI 95 % 1.061, 7.972, p < 0.05). Conclusion: There are significant differences in match distribution between allopathic and osteopathic medical schools for surgical subspecialties. This may be due to differences in clinical exposure to these specialties offered to students at their respective medical schools. Medical schools can support students' successful match into competitive surgical subspecialties by increasing students' exposure through elective rotations.
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Intracortical microstimulation (ICMS) is a method for restoring sensation to people with paralysis as part of a bidirectional brain-computer interface to restore upper limb function. Evoking tactile sensations of the hand through ICMS requires precise targeting of implanted electrodes. Here we describe the presurgical imaging procedures used to generate functional maps of the hand area of the somatosensory cortex and subsequent planning that guided the implantation of intracortical microelectrode arrays. In five participants with cervical spinal cord injury, across two study locations, this procedure successfully enabled ICMS-evoked sensations localized to at least the first four digits of the hand. The imaging and planning procedures developed through this clinical trial provide a roadmap for other brain-computer interface studies to ensure successful placement of stimulation electrodes.
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Time-order error, a psychophysical phenomenon in which the duration in between successive stimuli alters perception, has been studied for decades by neuroscientists and psychologists. To date, however, the locus of these effects is unknown. We use intracortical microstimulation of somatosensory cortex in humans as a tool to bypass initial stages of processing and restrict the possible locations that signals could be modified. We find that, using both amplitude discrimination and magnitude estimation paradigms, intracortical microstimulation reliably evoked time-order errors across all participants. Points of subjective equality were symmetrically shifted during amplitude discrimination experiments and the intensity of a successive stimulus was perceived as being more intense when compared to single stimulus trials in magnitude estimation experiments. The error was reduced for both paradigms at longer inter-stimulus intervals. These results show that direct activation of primary somatosensory cortex is sufficient to induce time-order errors.
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INTRODUCTION: Integrated plastic surgery residency is one of the most competitive medical specialties. Although previous studies have surveyed integrated plastic surgery residency program directors regarding desired applicant characteristics, there is a paucity of literature assessing detailed application characteristics and reported match outcomes from applicants in recent application cycles. This study examines application characteristics associated with matching into integrated plastic surgery residency from 2017 to 2023. METHODS: The authors accessed the Texas Seeking Transparency in Application to Residency database, which contains survey information from graduating medical students nationwide regarding residency application characteristics and specialties/programs to which applications were submitted. Characteristics of matched versus unmatched applicants between 2017 and 2023 were compared using χ 2 and 2-sided, independent t tests. Univariate logistic regression models were used to assess predictors of a successful match. RESULTS: A total of 381 integrated plastic surgery residency applicants responded to the Texas Seeking Transparency in Application to Residency survey from 2017 to 2023. Mean United States Medical Licensing Exam Step 2 CK scores; the number of away rotations, interview offers, and honored clerkships; and Alpha Omega Alpha membership rate were significantly associated with and predictive of matching. Preference signaling of programs was associated with an increased interview offer rate. CONCLUSIONS: Higher board examination scores, increasing numbers of honored clerkships, away rotations, and Alpha Omega Alpha membership were identified as statistically significant predictors of matching into integrated plastic surgery residency. Prospective applicants should use this information to help guide their efforts in these areas that appear to be associated with a successful transition to residency.
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Internship and Residency , Surgery, Plastic , Humans , Surgery, Plastic/education , Texas , Male , Female , Databases, Factual , Surveys and Questionnaires , Personnel Selection , School Admission Criteria , Adult , Educational Measurement , Career ChoiceABSTRACT
Investigating the molecular, cellular, and tissue-level changes caused by disease, and the effects of pharmacological treatments across these biological scales, necessitates the use of multiscale computational modeling in combination with experimentation. Many diseases dynamically alter the tissue microenvironment in ways that trigger microvascular network remodeling, which leads to the expansion or regression of microvessel networks. When microvessels undergo remodeling in idiopathic pulmonary fibrosis (IPF), functional gas exchange is impaired due to loss of alveolar structures and lung function declines. Here, we integrated a multiscale computational model with independent experiments to investigate how combinations of biomechanical and biochemical cues in IPF alter cell fate decisions leading to microvascular remodeling. Our computational model predicted that extracellular matrix (ECM) stiffening reduced microvessel area, which was accompanied by physical uncoupling of endothelial cell (ECs) and pericytes, the cells that comprise microvessels. Nintedanib, an FDA-approved drug for treating IPF, was predicted to further potentiate microvessel regression by decreasing the percentage of quiescent pericytes while increasing the percentage of pericytes undergoing pericyte-myofibroblast transition (PMT) in high ECM stiffnesses. Importantly, the model suggested that YAP/TAZ inhibition may overcome the deleterious effects of nintedanib by promoting EC-pericyte coupling and maintaining microvessel homeostasis. Overall, our combination of computational and experimental modeling can explain how cell decisions affect tissue changes during disease and in response to treatments.
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BACKGROUND: Distal femur fractures are known to have challenging nonunion rates. Despite various available treatment methods aimed to improve union, optimal interventions are yet to be determined. Importantly, there remains no standard agreement on what defines radiographic union. Although various proposed criteria of defining radiographic union exist in the literature, there is no clear consensus on which criteria provide the most precise measurement. The use of inconsistent measures of fracture healing between studies can be problematic and limits their generalizability. Therefore, this systematic review aims to identify how fracture union is defined based on radiographic parameters for surgically treated distal femur fractures in current literature. METHODS: In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, Medline, EMBASE, Cochrane Central Register of Controlled Trials, and Web of Science Core Collection databases were searched from inception to October 2022. Studies that addressed surgically treated distal femur fractures with reported radiographic union assessment were included. Outcomes extracted included radiographic definition of union; any testing of validity, reliability, or responsiveness; reported union rate; reported time to fracture union; and any functional outcomes correlated with radiographic union. RESULTS: Sixty articles with 3,050 operatively treated distal femur fractures were included. Operative interventions included lateral locked plate (42 studies), intramedullary nail (15 studies), dynamic condylar screw or blade plate (7 studies), dual plate or plate and nail construct (5 studies), distal anterior-posterior/posterior-anterior screws (1 study), and external fixation with a circular frame (1 study). The range of mean follow-up time reported was 4.3 to 44 months. The most common definitions of fracture union included "bridging or callus formation across 3 of 4 cortices" in 26 (43%) studies, "bony bridging of cortices" in 21 (35%) studies, and "complete bridging of cortices" in 9 (15%) studies. Two studies included additional assessment of radiographic union using the Radiographic Union Scale in Tibial fracture (RUST) or modified Radiographic Union Scale in Tibial fracture (mRUST) scores. One study included description of validity, and the other study included reliability testing. The reported mean union rate of distal femur fractures was 89% (range 58%-100%). The mean time to fracture union was documented in 49 studies and found to be 18 weeks (range 12-36 weeks) in 2,441 cases. No studies reported correlations between functional outcomes and radiographic parameters. CONCLUSION: The current literature evaluating surgically treated distal femur fractures lacks consistent definition of radiographic fracture union, and the appropriate time point to make this judgement is unclear. To advance surgical optimization, it is necessary that future research uses validated, reliable, and continuous measures of radiographic bone healing and correlation with functional outcomes. LEVEL OF EVIDENCE: Level IV. See Instructions for Authors for a complete description of levels of evidence.
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Femoral Fractures, Distal , Tibial Fractures , Humans , Reproducibility of Results , Bone Plates , Bone ScrewsABSTRACT
Introduction. We have examined four burials from the St Mary Magdalen mediaeval leprosarium cemetery in Winchester, Hampshire, UK. One (Sk.8) was a male child, two (Sk.45 and Sk.52) were adolescent females and the fourth (Sk.512) was an adult male. The cemetery was in use between the 10th and 12th centuries. All showed skeletal lesions of leprosy. Additionally, one of the two females (Sk.45) had lesions suggestive of multi-cystic tuberculosis and the second (Sk.52) of leprogenic odontodysplasia (LO), a rare malformation of the roots of the permanent maxillary incisors.Gap statement. Relatively little is known of the manifestations of lepromatous leprosy (LL) in younger individuals from the archaeological record.Aims and Methodology. To address this, we have used ancient DNA testing and osteological examination of the individuals, supplemented with X-ray and microcomputed tomography (micro-CT) scan as necessary to assess the disease status.Results and Conclusions. The presence of Mycobacterium leprae DNA was confirmed in both females, and genotyping showed SNP type 3I-1 strains but with a clear genotypic variation. We could not confirm Mycobacterium tuberculosis complex DNA in the female individual SK.45. High levels of M. leprae DNA were found within the pulp cavities of four maxillary teeth from the male child (Sk.8) with LO, consistent with the theory that the replication of M. leprae in alveolar bone may interfere with root formation at key stages of development. We report our biomolecular findings in these individuals and review the evidence this site has contributed to our knowledge of mediaeval leprosy.
Subject(s)
Leprosy, Multibacillary , Leprosy , Adult , Child , Humans , Male , Female , Adolescent , X-Ray Microtomography , Leprosy/microbiology , Mycobacterium leprae/genetics , DNA, Bacterial/genetics , United KingdomABSTRACT
OBJECTIVE: Research years during medical school are becoming increasingly common amongst applicants to competitive residency programs. As many of these positions are unpaid, it is important to consider the financial implications of these experiences and the feasibility of participation from students of all backgrounds. This study aims to quantify the cost of a research year during medical school. DESIGN/SETTING: We identified the top 50 NIH-funded medical schools of 2022 and obtained cost-of-living information for each of their respective counties. Estimated loan interest accrual resulting from a research year was calculated using information on the cost of attendance to medical school and annual interest rates for federal education loans. Cost-of-living calculations were stratified by geographic region, and interest accrual calculations by timing of research year and attendance at public versus private medical schools. RESULTS: Top 50 NIH-funded medical schools in the West are located in counties with the highest mean and median costs of living, each approaching nearly $45,000 per year. Medical schools in the Midwest are located in counties with the lowest mean and median cost of living, at less than $36,000 annually. Estimated loan interest accrual resulting from a research year ranges from $3177 to $17,789, depending on timing of the research year and type of medical school attended. CONCLUSIONS: This study exemplifies the significant financial burden that a research year can impose on medical students. As more residency applicants pursuing competitive specialties opt for research years during medical school, it is important to consider the associated financial implications. Many research year opportunities are unpaid or underpaid, which may prevent interested individuals from participating; this is especially the case for those who are from lower socioeconomic backgrounds. Moving forward, it is imperative that we ensure the availability of equitable and funded research year opportunities for students of all backgrounds.
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Internship and Residency , Medicine , Students, Medical , Humans , Schools, Medical , Training Support , EfficiencyABSTRACT
BACKGROUND: Leaving the patella unresurfaced in total knee arthroplasty (TKA) has increased significantly over the past decade in the United States, likely due to modern patella-friendly implants, complications with resurfacing, and the knowledge that historical studies were scientifically confounded. This study evaluated revision-free survivorship out to 8.5 years in a cohort of contemporary primary TKAs with patella-friendly femoral components and unresurfaced patellae. METHODS: A total of 1,053 consecutive primary TKAs with unresurfaced patellae were retrospectively reviewed. A selective patellar nonresurfacing protocol was used for all cases. Kaplan-Meier survivorship estimates were calculated based on patellar revision and the latest follow-up. An aggressive lateral patellar facetectomy was performed in 78% (823 of 1,053) of cases. The cohort was 62% women and 43% American Society of Anesthesiologists physical status classification I or II with a mean age and body mass index of 65 years (range, 35 to 94) and 35 kg/m2 (range, 18 to 65), respectively. RESULTS: A total of 4 (0.4%, 4 of 1,053) unresurfaced patellae were revised. Three were resurfaced as part of other procedures: 2 for global instability and one for aseptic loosening at a mean of 1.6 years; and one patella was resurfaced by an outside surgeon for unexplained pain. The all-cause revision-free survivorship estimate specifically related to the patella was 98.9% (95% confidence interval, 98 to 100) out to 8.5 years. No significant difference in survivorship was related to patellae with or without a lateral patellar facetectomy (99.5 versus 98.1%, P ≥ .191); however, 3 of 4 patellar revisions occurred in TKAs without a lateral patellar facetectomy (P = .035). CONCLUSIONS: The results of this study demonstrate excellent revision-free survivorship related to unresurfaced patellae, particularly when a lateral facetectomy was performed. These early to midterm results using modern patella-friendly femoral components are promising and comparable to resurfaced patellae in the literature. LEVEL OF EVIDENCE: IV.
Subject(s)
Arthroplasty, Replacement, Knee , Knee Prosthesis , Patella , Humans , Arthroplasty, Replacement, Knee/methods , Female , Male , Patella/surgery , Aged , Middle Aged , Retrospective Studies , Aged, 80 and over , Adult , Prosthesis Failure , Reoperation/statistics & numerical data , Treatment Outcome , Follow-Up Studies , Kaplan-Meier EstimateABSTRACT
BACKGROUND: Ticks and tick-borne diseases pose significant challenges to cattle production, thus the species identification of ticks and knowledge on their presence, abundance, and dispersal are necessary for the development of effective control measures. The standard method of inspection for the presence of ticks is the visual and physical examination of restrained animals, but the limitations of human sight and touch can allow larval, nymphal, and unfed adult ticks to remain undetected due to their small size and site of attachment. However, Raman spectroscopy, an analytical tool widely used in agriculture and other sectors, shows promise for the identification of tick species in infested cattle. Raman spectroscopy is a non-invasive and efficient method that employs the interaction between molecules and light for the identification of the molecular constituents of specimens. METHODS: Raman spectroscopy was employed to analyze the structure and composition of tick feces deposited on host skin and hair during blood-feeding. Feces of 12 species from a total of five genera and one subgenus of ixodid ticks were examined. Spectral data were subjected to partial least squares discriminant analysis, a machine-learning model. We also used Raman spectroscopy and the same analytical procedures to compare and evaluate feces of the horn fly Haematobia irritans after it fed on cattle. RESULTS: Five genera and one sub-genus at overall true prediction rates ranging from 92.3 to 100% were identified from the Raman spectroscopy data of the tick feces. At the species level, Dermacentor albipictus, Dermacentor andersoni and Dermacentor variabilis at overall true prediction rates of 100, 99.3 and 100%, respectively, were identified. There were distinct differences between horn fly and tick feces with respect to blood and guanine vibrational frequencies. The overall true prediction rate for the separation of tick and horn fly feces was 98%. CONCLUSIONS: Our findings highlight the utility of Raman spectroscopy for the reliable identification of tick species from their feces, and its potential application for the identification of ticks from infested cattle in the field.
Subject(s)
Dermacentor , Ixodidae , Tick Infestations , Ticks , Humans , Animals , Cattle , Spectrum Analysis, Raman , Feces , Tick Infestations/veterinaryABSTRACT
STUDY OBJECTIVES: Clinical practice guidelines recommend screening all children with Down syndrome for obstructive sleep apnea with polysomnography by age 4 years. Because persistent obstructive sleep apnea (obstructive apnea-hypopnea index > 1 event/h) following adenotonsillectomy (T&A) is common in children with Down syndrome, it is important to know whether clinicians can rely on parental assessment postoperatively. The primary objective is to identify accuracy of parental perception of nighttime breathing following T&A compared with preoperative assessment. METHODS: Patients with Down syndrome who underwent T&A along with polysomnography prior to and after the surgical procedure were included. Parents completed a 3-question pre- and postsurgery survey regarding nighttime symptoms. The responses were categorized into 3 groups: infrequent (< 3 nights/wk), sometimes (> 3 nights/wk but < 6 nights/wk), or frequent (≥ 6 nights/wk) on at least 1 question. The primary end point was identifying the accuracy of parental perception of nighttime breathing in children with Down syndrome following T&A. RESULTS: A total of 256 children met inclusion criteria, of which 117 (46%) were included. A total of 71 (68%) children had an obstructive apnea-hypopnea index > 5 events/h preoperatively compared with 55 (47%) postoperatively. There was no association between parents' perception of symptoms and obstructive sleep apnea categorization postoperatively (P > .05) or of parents' perception of symptoms improving and obstructive sleep apnea categorization improving postoperatively (P > .05). CONCLUSIONS: Despite previous experience, parents are unable to predict nighttime breathing patterns following a T&A. We recommend obtaining a polysomnogram rather than relying on parental assessment to determine whether a T&A has been successful. CITATION: Chabuz CA, Lackey TG, Pickett KL, Friedman NR. Accuracy of parental perception of nighttime breathing in children with Down syndrome after adenotonsillectomy. J Clin Sleep Med. 2024;20(2):237-243.
Subject(s)
Down Syndrome , Sleep Apnea, Obstructive , Tonsillectomy , Child , Humans , Child, Preschool , Down Syndrome/complications , Down Syndrome/surgery , Tonsillectomy/methods , Adenoidectomy/methods , Sleep Apnea, Obstructive/complications , Sleep Apnea, Obstructive/surgery , Sleep Apnea, Obstructive/diagnosis , Parents , Respiration , PerceptionABSTRACT
BACKGROUND: Reverse total shoulder arthroplasty (RTSA) is increasingly used as a treatment modality for various pathologies. The purpose of this review is to identify preoperative risk factors associated with loss of internal rotation (IR) after RTSA. METHODS: A systematic review was conducted using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Ovid MEDLINE, Ovid Embase, and Scopus were queried. The inclusion criteria were as follows: articles in English language, minimum 1-year follow-up postoperatively, study published after 2012, a minimum of 10 patients in a series, RTSA surgery for any indication, and explicitly reported IR. The exclusion criteria were as follows: articles whose full text was unavailable or that were unable to be translated to English language, a follow-up of less than 1 year, case reports or series of less than 10 cases, review articles, studies in which tendon transfers were performed at the time of surgery, procedures that were not RTSA, and studies in which the range of motion in IR was not reported. RESULTS: The search yielded 3792 titles, and 1497 duplicate records were removed before screening. Ultimately, 16 studies met the inclusion criteria with a total of 5124 patients who underwent RTSA. Three studies found that poor preoperative functional IR served as a significant risk factor for poor postoperative IR. Eight studies addressed the impact of subscapularis, with 4 reporting no difference in IR based on subscapularis repair and 4 reporting significant improvements with subscapularis repair. Among studies with sufficient power, BMI was found to be inversely correlated with degree of IR after RTSA. Preoperative opioid use was found to negatively affect IR. Other studies showed that glenoid retroversion, component lateralization, and individualized component positioning affected postoperative IR. CONCLUSIONS: This study found that preoperative IR, individualized implant version, preoperative opioid use, increased body mass index and increased glenoid lateralization were all found to have a significant impact on IR after RTSA. Studies that analyzed the impact of subscapularis repair reported conflicting results.