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Background: Excessive shoulder anterior force has been implicated in pathology of the rotator cuff in little league and professional baseball pitchers; in particular, anterior laxity, posterior stiffness, and glenohumeral joint impingement. Distinctly characterized motions associated with excessive shoulder anterior force remain poorly understood. Methods: High school and professional pitchers were instructed to throw fastballs while being evaluated with 3D motion capture (480 Hz). A supplementary random forest model was designed and implemented to identify the most important features for regressing to shoulder anterior force, with subsequent standardized regression coefficients to quantify directionality. Results: 130 high school pitchers (16.3 ± 1.2 yrs; 179.9 ± 7.7 cm; 74.5 ± 12.0 kg) and 322 professionals (21.9 ± 2.1 yrs; 189.7 ± 5.7 cm; 94.8 ± 9.5 kg) were included. Random forest models determined nearly all the variance for professional pitchers (R2 = 0.96), and less than half for high school pitchers (R2 = 0.41). Important predictors of shoulder anterior force in high school pitchers included: trunk flexion at maximum shoulder external rotation (MER) (X.IncMSE = 2.4, β = −0.23, p < 0.001), shoulder external rotation at ball release (BR)(X.IncMSE = 1.7, β = −0.34, p < 0.001), and shoulder abduction at BR (X.IncMSE = 3.1, β = 0.17, p < 0.001). In professional pitchers, shoulder horizontal adduction at foot contact (FC) was the highest predictor (X.IncMSE = 13.9, β = 0.50, p < 0.001), followed by shoulder external rotation at FC (X.IncMSE = 3.6, β = 0.26, p < 0.001), and maximum elbow extension velocity (X.IncMSE = 8.5, β = 0.19, p < 0.001). Conclusion: A random forest model successfully selected a subset of features that accounted for the majority of variance in shoulder anterior force for professional pitchers; however, less than half of the variance was accounted for in high school pitchers. Temporal and kinematic movements at the shoulder were prominent predictors of shoulder anterior force for both groups. Clinical relevance: : Our statistical model successfully identified a combination of features with the ability to adequately explain the majority of variance in anterior shoulder force among high school and professional pitchers. To minimize shoulder anterior force, high school pitchers should emphasize decreased shoulder abduction at BR, while professionals can decrease shoulder horizontal adduction at FC. [ABSTRACT FROM AUTHOR]

Introduction: Autologous fat grafting (AFG) is a common technique used to enhance aesthetic outcomes in postmastectomy breast reconstruction patients. Adipokines are hormones secreted by adipose tissue that play a critical role in regulating metabolic processes and the immune system. However, dysregulated adipokine secretion and signaling can contribute to the development and progression of cancer by promoting angiogenesis, altering the immune response, and inducing the epithelial mesenchymal transition. We aimed to assess how breast cancer cells behave in conditioned media derived from fat grafting lipoaspirates and gain a better understanding of the potential interactions that may occur within the tumor microenvironment., Methods: Patients who were undergoing AFG as a part of breast reconstruction at NY-Presbyterian/Weill Cornell Medical Center between March 2021 and July 2023 were consented and enrolled in the study. This study was approved by the Weill Cornell Medicine Institutional Review Board (#20-10022850-14). Conditioned media is created using 20% of patient lipoaspirate secretome and 80% starving media. The growth of MCF-7, a human ER/PR+ breast cancer cell line, in conditioned media is assessed using CyQUANT., Results: The breast cancer cells incubated in conditioned media displayed similar growth trends as those in complete media, which is enriched for cell growth (P > 0.05). MCF-7 cell behavior in conditioned media differed significantly from their proliferation patterns when serum starved in 100% starving media (P < 0.05)., Discussion: Our results suggest that there may be inherent factors within the lipoaspirate that may promote MCF-7 proliferation. One potential implication is that AFG used for breast reconstruction should be delayed until local-regional disease control has been established. In addition, based on the in vitro proliferation patterns of breast cancer cells in conditioned media, the safety profile of AFG may be enhanced if the procedure is performed after attaining negative margins and the completion breast cancer treatment., Competing Interests: Conflicts of interest and sources of funding: None declared., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Purpose: Breast anesthesia after mastectomy and reconstruction has been an ongoing concern with few improvements made in recent years. At present, there is a lack of studies evaluating the impact of comorbidities on sensation restoration. Identifying risk factors (RF) will be helpful with preoperative counseling., Methods: This was a prospective study on patients who underwent mastectomy and immediate implant-based or neurotized deep inferior epigastric perforator (DIEP) flap-based reconstruction. Neurosensory testing was performed at predefined time points using a pressure specified device. Patients were stratified based on reconstruction type and comorbidities, including obesity (≥30 kg/m2), age (>55 years), hypertension, alcohol use, and smoking status. Sensory comparisons among the comorbidity groups were conducted using unpaired 2-sample t tests., Results: A total of 239 patients were included in this study with 109 patients in the implant cohort and 131 patients in the DIEP cohort. One patient underwent bilateral reconstruction using both reconstructive modalities. Preoperatively, age older than 55 years was identified as an RF for reduced breast sensation in the implant cohort (difference in threshold, 10.7 g/mm2), whereas obesity was identified as an RF in the DIEP cohort (difference in threshold, 8 g/mm2). During the first 2 years postreconstruction, age older than 55 years and tobacco use history were found to be negatively correlated with breast sensation for both cohorts. With DIEP reconstruction specifically, obesity was identified as an additional RF during the early postoperative period. Of note, none of the comorbidities were found to be long-term RFs for reduced breast sensitivity. All breast sensation levels returned to comparable levels across all comorbidities by 4 years postreconstruction., Conclusions: Currently, various comorbidities have been recognized as RFs for several postoperative complications including extended postoperative stay, necrosis, infection, and reoperation. However, our findings suggest that, although age, smoking history, and obesity showed transient associations with reduced breast sensation during the initial years postreconstruction, they play no role in the long-term potential of sensory nerve regeneration., Competing Interests: Conflicts of interest and source of funding: Dr Otterburn formerly received research support from AxoGen Inc (Alachua, FL) to evaluate return of sensation after breast reconstruction. All other authors have no personal financial disclosures or commercial associations., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)