Association of musculoskeletal involvement with lung function and mortality in patients with idiopathic pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a progressive disease associated with high mortality. Low muscle mass, frailty and sarcopenia lead to functional impairment that negatively impact quality of life and survival but are not used in clinical practice. We aimed to determine the association of Fat-free mass index (FFMI) and frailty with lung function, exercise tolerance and survival in patients with IPF. In this study, 70 patients with IPF underwent assessment of body composition, lung function, 6-min walk distance (6MWD) testing, hand grip strength, quality of life (QoL) assessment by St. George's Respiratory questionnaire (SGRQ) and frailty assessment using the SHARE-FI tool. FFMI was calculated using pectoralis muscle cross-sectional area (PM-CSA) on CT chest images and the lowest quartile defined reduced muscle mass. Sarcopenia was defined as low FFMI and handgrip strength. Regression analyses were conducted to determine predictive value of frailty, low FFMI and sarcopenia on clinical outcomes. The Cox proportional hazards model was used to analyze the impact of FFMI and frailty score on survival. The mean age was 70 years with moderate impairment in lung function (mean ppFVC 68.5%, ppDLCO 45.6%). Baseline forced vital capacity (p < 0.001), diffusion capacity of lung for carbon monoxide (p = < 0.01), 6WMD (p < 0.05) were significantly lower in frail patients compared to non-frail patients. BMI was found to closely correlate with FFMI (r = 0.79, p < 0.001), but not with frailty score (r = - 0.2, p = 0.07). Frailty was a significant predictor of FVC, DLCO, 6MWD, SGRQ scores when adjusted for age and gender. Muscle mass and sarcopenia were significant predictors of FVC, DLCO, but not 6MWD or QoL scores. Multivariate cox-proportional hazards ratio model adjusting for age and gender showed that frailty was significantly associated with increased mortality (HR = 2.6, 95% CI 1.1-6.1). Low FFMI (HR = 1.3, 95% CI 0.6-2.8), and sarcopenia (HR = 2.1, 95% CI 0.8-5.3), though associated with a trend to increased mortality, were not statistically significant. Frailty is associated with lower lung function and higher mortality in patients with IPF. Longitudinal evaluations are necessary to further determine the associations between low FFMI, sarcopenia and frailty with outcomes in IPF.

Pectoralis Muscle Index as Predictor of Outcomes in Patients With Severe Blunt Chest Wall Injury.

INTRODUCTION: Sarcopenia has been shown to portend worse outcomes in injured patients; however, little is known about the impact of thoracic muscle wasting on outcomes of patients with chest wall injury. We hypothesized that reduced pectoralis muscle mass is associated with poor outcomes in patients with severe blunt chest wall injury. METHODS: All patients admitted to the intensive care unit between 2014 and 2019 with blunt chest wall injury requiring mechanical ventilation were retrospectively identified. Blunt chest wall injury was defined as the presence of one or more rib fractures as a result of blunt injury mechanism. Exclusion criteria included lack of admission computed tomography imaging, penetrating trauma, <18 y of age, and primary neurologic injury. Thoracic musculature was assessed by measuring pectoralis muscle cross-sectional area (cm2) that was obtained at the fourth thoracic vertebral level using Slice-O-Matic software. The area was then divided by the patient height in meters2 to calculate pectoralis muscle index (PMI) (cm2/m2). Patients were divided into two groups, 1) the lowest gender-specific quartile of PMI and 2) second-fourth gender-specific PMI quartiles for comparative analysis. RESULTS: One hundred fifty-three patients met the inclusion criteria with a median (interquartile range) age 48 y (34-60), body mass index of 30.1 kg/m2 (24.9-34.6), and rib score of 3.0 (2.0-4.0). Seventy-five percent of patients (116/153) were male. Fourteen patients (8%) had prior history of chronic lung disease. Median (IQR) intensive care unit length-of-stay and duration of mechanical ventilation (MV) was 18.0 d (13.0-25.0) and 15.0 d (10.0-21.0), respectively. Seventy-three patients (48%) underwent tracheostomy and nine patients (6%) expired during hospitalization. On multivariate linear regression, reduced pectoralis muscle mass was associated with increased MV duration when adjusting for rib score and injury severity score (ß 5.98, 95% confidence interval 1.28-10.68, P = 0.013). CONCLUSIONS: Reduced pectoralis muscle mass is associated with increased duration of MV in patients with severe blunt chest wall injury. Knowledge of this can help guide future research and risk stratification of critically ill chest wall injury patients.

First transcriptomic insight into the working muscles of racing pigeons during a competition flight.

BACKGROUND: The currently known homing pigeon is a result of a sharp one-sided selection for flight characteristics focused on speed, endurance, and spatial orientation. This has led to extremely well-adapted athletic phenotypes in racing birds. METHODS: Here, we identify genes and pathways contributing to exercise adaptation in sport pigeons by applying next-generation transcriptome sequencing of m.pectoralis muscle samples, collected before and after a 300 km competition flight. RESULTS: The analysis of differentially expressed genes pictured the central role of pathways involved in fuel selection and muscle maintenance during flight, with a set of genes, in which variations may therefore be exploited for genetic improvement of the racing pigeon population towards specific categories of competition flights. CONCLUSIONS: The presented results are a background to understanding the genetic processes in the muscles of birds during flight and also are the starting point of further selection of genetic markers associated with racing performance in carrier pigeons.

Pre-operative pectoralis muscle area index is associated with biomarkers of inflammation and endotoxemia and predicts clinical outcomes after left ventricular assist device implantation: A cohort study.

BACKGROUND: Pre-left ventricular assist device (LVAD) pectoralis muscle assessment, an estimate of sarcopenia, has been associated with postoperative mortality and gastrointestinal bleeding, though its association with inflammation, endotoxemia, length-of-stay (LOS), and readmissions remains underexplored. METHODS: This was a single-center cohort study of LVAD patients implanted 1/2015-10/2018. Preoperative pectoralis muscle area was measured on chest computed tomography (CT), adjusted for height squared to derive pectoralis muscle area index (PMI). Those with PMI in the lowest quintile were defined as low-PMI cohort; all others constituted the reference cohort. Biomarkers of inflammation (interleukin-6, adiponectin, tumor necrosis factor-α [TNFα]) and endotoxemia (soluble (s)CD14) were measured in a subset of patients. RESULTS: Of the 254 LVAD patients, 95 had a preoperative chest CT (median days pre-LVAD: 7 [IQR 3-13]), of whom 19 (20.0%) were in the low-PMI cohort and the remainder were in the reference cohort. Compared with the reference cohort, the low-PMI cohort had higher levels of sCD14 (2594 vs. 1850 ng/mL; p = 0.04) and TNFα (2.9 vs. 1.9 pg/mL; p = 0.03). In adjusted analyses, the low-PMI cohort had longer LOS (incidence rate ratio 1.56 [95% confidence interval 1.16-2.10], p = 0.004) and higher risk of 90-day and 1-year readmissions (subhazard ratio 5.48 [1.88-16.0], p = 0.002; hazard ratio 1.73 [1.02-2.94]; p = 0.04, respectively). CONCLUSIONS: Pre-LVAD PMI is associated with inflammation, endotoxemia, and increased LOS and readmissions.

Immediate Unilateral Subpectoral Implant-Based Breast Reconstruction does not Impair Pulmonary Functions: A Preliminary Prospective Study.

BACKGROUND: Implant-based breast reconstruction is one of the most common procedures among women with breast cancer undergoing mastectomy. Prosthetic devices may be positioned either beneath or above the pectoralis major muscle, which is considered an accessory muscle of ventilation. This preliminary prospective study aimed to investigate whether subpectoral unilateral implant-based breast reconstruction has any effect on patients' pulmonary functions. METHODS: A prospective study of fourteen women who underwent immediate unilateral implant-based subpectoral breast reconstruction by a single surgeon over 10 months was conducted. Spirometry and maximal voluntary ventilation tests were conducted 1 day prior to surgery, and 1- and 3 months following breast reconstruction. ANOVA or Friedman test were used to compare pulmonary function tests before and after surgery. RESULTS: Fourteen patients completed the study protocol. No statistically significant differences were found when comparing spirometry parameters in the three time points. CONCLUSIONS: Pectoralis muscle release does not impair pulmonary function among patients undergoing immediate unilateral implant-based breast reconstruction following mastectomy. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Establishment and application of the BRP prognosis model for idiopathic pulmonary fibrosis.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is the most common idiopathic interstitial lung disease. Clinical models to accurately evaluate the prognosis of IPF are currently lacking. This study aimed to construct an easy-to-use and robust prediction model for transplant-free survival (TFS) of IPF based on clinical and radiological information. METHODS: A multicenter prognostic study was conducted involving 166 IPF patients who were followed up for 3 years. The end point of follow-up was death or lung transplantation. Clinical information, lung function tests, and chest computed tomography (CT) scans were collected. Body composition quantification on CT was performed using 3D Slicer software. Risk factors in blood routine examination-radiology-pulmonary function (BRP) were identified by Cox regression and utilized to construct the "BRP Prognosis Model". The performance of the BRP model and the gender-age-physiology variables (GAP) model was compared using time-ROC curves, calibration curves, and decision curve analysis (DCA). Furthermore, histopathology fibrosis scores in clinical specimens were compared between the different risk stratifications identified by the BRP model. The correlations among body composition, lung function, serum inflammatory factors, and profibrotic factors were analyzed. RESULTS: Neutrophil percentage > 68.3%, pericardial adipose tissue (PAT) > 94.91 cm3, pectoralis muscle radiodensity (PMD) ≤ 36.24 HU, diffusing capacity of the lung for carbon monoxide/alveolar ventilation (DLCO/VA) ≤ 56.03%, and maximum vital capacity (VCmax) < 90.5% were identified as independent risk factors for poor TFS among patients with IPF. We constructed a BRP model, which showed superior accuracy, discrimination, and clinical practicability to the GAP model. Median TFS differed significantly among patients at different risk levels identified by the BRP model (low risk: TFS > 3 years; intermediate risk: TFS = 2-3 years; high risk: TFS ≈ 1 year). Patients with a high-risk stratification according to the BRP model had a higher fibrosis score on histopathology. Additionally, serum proinflammatory markers were positively correlated with visceral fat volume and infiltration. CONCLUSIONS: In this study, the BRP prognostic model of IPF was successfully constructed and validated. Compared with the commonly used GAP model, the BRP model had better performance and generalization with easily obtainable indicators. The BRP model is suitable for clinical promotion.

CT-derived pectoralis composition and incident pneumonia hospitalization using fully automated deep-learning algorithm: multi-ethnic study of atherosclerosis.

BACKGROUND: Pneumonia-related hospitalization may be associated with advanced skeletal muscle loss due to aging (i.e., sarcopenia) or chronic illnesses (i.e., cachexia). Early detection of muscle loss may now be feasible using deep-learning algorithms applied on conventional chest CT. OBJECTIVES: To implement a fully automated deep-learning algorithm for pectoralis muscle measures from conventional chest CT and investigate longitudinal associations between these measures and incident pneumonia hospitalization according to Chronic Obstructive Pulmonary Disease (COPD) status. MATERIALS AND METHODS: This analysis from the Multi-Ethnic Study of Atherosclerosis included participants with available chest CT examinations between 2010 and 2012. We implemented pectoralis muscle composition measures from a fully automated deep-learning algorithm (Mask R-CNN, built on the Faster Region Proposal Network (R-) Convolutional Neural Network (CNN) with an extension for mask identification) for two-dimensional segmentation. Associations between CT-derived measures and incident pneumonia hospitalizations were evaluated using Cox proportional hazards models adjusted for multiple confounders which include but are not limited to age, sex, race, smoking, BMI, physical activity, and forced-expiratory-volume-at-1 s-to-functional-vital-capacity ratio. Stratification analyses were conducted based on baseline COPD status. RESULTS: This study included 2595 participants (51% female; median age: 68 (IQR: 61, 76)) CT examinations for whom we implemented deep learning-derived measures for longitudinal analyses. Eighty-six incident pneumonia hospitalizations occurred during a median 6.67-year follow-up. Overall, pectoralis muscle composition measures did not predict incident pneumonia. However, in fully-adjusted models, only among participants with COPD (N = 507), CT measures like extramyocellular fat index (hazard ratio: 1.98, 95% CI: 1.22, 3.21, p value: 0.02), were independently associated with incident pneumonia. CONCLUSION: Reliable deep learning-derived pectoralis muscle measures could predict incident pneumonia hospitalization only among participants with known COPD. CLINICAL RELEVANCE STATEMENT: Pectoralis muscle measures obtainable at zero additional cost or radiation exposure from any chest CT may have independent predictive value for clinical outcomes in chronic obstructive pulmonary disease patients. KEY POINTS: •Identification of independent and modifiable risk factors of pneumonia can have important clinical impact on patients with chronic obstructive pulmonary disease. •Opportunistic CT measures of adipose tissue within pectoralis muscles using deep-learning algorithms can be quickly obtainable at zero additional cost or radiation exposure. •Deep learning-derived pectoralis muscle measurements of intermuscular fat and its subcomponents are independently associated with subsequent incident pneumonia hospitalization.

Pectoralis muscle area measured at T4 level is closely associated with adverse COVID-19 outcomes in hospitalized patients.

OBJECTIVES: Skeletal muscle area (SMA) at T4 level on chest computed tomography (CT) is a newly available method that can be used as a surrogate sarcopenia marker. The objective of this study is to evaluate association of SMA with adverse COVID-19 outcomes in hospitalized patients. METHODS: Hospitalized COVID-19 patients were prospectively recorded in a database containing age, gender, date of admission, date of outcome (discharge, mortality, presence of intensive care unit (ICU) stay, additional coding information (comorbidities, superimposed conditions). Admission CT-scans were retrospectively evaluated for segmentation (bilateral pectoralis major/minor, erector spinae, levator scapulae, rhomboideus minor and major and transversospinalis muscles) and SMA calculation using 3-D slicer software. RESULTS: 167 cases were evaluated (68 male, 72 female, 140 survived, 27 dead). Muscle area was lower in patients with ICU stay (p=0.023, p=0.018, p=0.008) and mortality outcome (p=0.004, p=0.007, p=0.002) for pectoralis, back and SMA. In multivariate Cox-regression analysis, hazard ratio (HR) value for the pectoralis muscle area value below 2800 mm2 was found to be 3.138(95% CI: 1.171-8.413) for mortality and 2.361(95% CI: 1.012-5.505) for ICU. CONCLUSIONS: Pectoralis muscle area measured at T4 level with 3-D slicer was closely associated with adverse outcomes (mortality, ICU stay) in hospitalized COVID-19 patients. Since early treatment methods for COVID-19 are being evaluated, this method may be a useful adjunct to clinical decision making in regard to prioritization.

Pectoralis muscle predicts distant metastases in breast cancer by deep learning radiomics.

BACKGROUND: Sarcopenia is associated with a poor prognosis in patients with breast cancer (BC). Currently, there are few quantitative assessments carried out between muscle biomarkers and distant metastasis using existing methods. PURPOSE: To assess the predictive value of the pectoralis muscle for BC distant metastasis, we developed a deep learning radiomics nomogram model (DLR-N) in this study. MATERIAL AND METHODS: A total of 493 patients with pathologically confirmed BC were registered. Image features were extracted from computed tomography (CT) images for each patient. Univariate and multivariate Cox regression analyses were performed to determine the independent prognostic factors for distant metastasis. The DLR-N was built based on independent prognostic factors and CT images to predict distant metastases. The model was assessed in terms of overall performance, discrimination, calibration, and clinical value. Finally, the predictive performance of the model was validated using the testing cohort. RESULTS: The developed DLR-N combined multiple radiomic features and clinicopathological factors and demonstrated excellent predictive performance. The C-index of the training cohort was 0.983 (95% confidence interval [CI] = 0.969-0.998) and the C-index of the testing cohort was 0.948 (95% CI = 0.917-0.979). Decision curve analysis (DCA) showed that patients could benefit more from incorporating multimodal radiomic features into clinicopathological models. CONCLUSIONS: DLR-N verified that there were biomarkers at the level of the fourth thoracic vertebra (T4) that affected distant metastasis. Multimodal prediction models based on deep learning could be a potential method to aid in the prediction of distant metastases in patients with BC.

Prenatal diagnosis of Poland-Möbius syndrome by multimodality fetal imaging.

We describe prenatal diagnosis of Poland-Möbius syndrome using a combination of ultrasound and MRI. Poland syndrome was diagnosed based on absence of the pectoralis muscles associated with dextroposition of the fetal heart and elevation of the left diaphragm. Associated brain anomalies that led to the diagnosis of Poland-Möbius syndrome, included ventriculomegaly, hypoplastic cerebellum, tectal beaking, and a peculiar flattening of the posterior aspect of the pons and medulla oblongata, which has been reported by postnatal diffusion tensor imaging studies as a reliable neuroimaging marker for Möbius syndrome. Since abnormalities of cranial nerves VI and VII may be difficult to detect prenatally, careful attention to the appearance of the brain stem as illustrated in the current report may aid in the prenatal diagnosis of Möbius syndrome.

Pectoralis muscle index might be a factor associated with frailty in older women with breast cancer.

BACKGROUND: To investigate the possible relationship between pectoralis muscle (PM) measurement and frailty in older women with breast cancer (BC) (preoperatively defined as stage 1, 2, and 3 diseases). METHODS: This retrospective, observational study was conducted at Konya Training and Research Hospital between June and December 2020. A total of 102 patients [median age 62.5 years, median follow-up period two years] were included in the study. PM measurements were obtained from thorax computerized tomography (CT). Pectoralis muscle index (PMI) was calculated by dividing the PM area by the height square of the patients (cm2/m2). Pectoralis muscle density (PMD) was evaluated using CT findings, including their Hounsfield Units (HU). Frailty status and sarcopenia-risk assessments were done by a telephone interview in September 2020 using the FRAIL index (categorized as robust or nonrobust) and SARC-F questionnaire (classified as no sarcopenia-risk or risk of sarcopenia), respectively. PM measurements were compared between robust and nonrobust patients and between patients with a risk of sarcopenia and no sarcopenia risk. RESULTS: The nonrobust patients had lower pectoralis major muscle index (PMaMI) (p = 0.041) and pectoralis major muscle density(PMaD) (p = 0.020) levels than robust patients in the whole study sample. PMI (p = 0.017) and PMaMI (p = 0.010) levels were significantly lower in the nonrobust patients than in robust patients with early-stage BC. Frailty status was positively correlated with age (rho: 0.621; p < 0.001), BC stage (rho: 0.220; p = 0.026), and SARC-F score (rho: 0.747; p < 0.001), and negatively correlated with PMaMI (rho: -0.197; p = 0.047) and PMaD (rho: -0.237; p = 0.016). There were significant associations between PMaMI (OR: 0.467, 95% Confidence Interval (CI): 0.226-0.962 p = 0.039) and PMI (OR: 0.543, 95% CI: 0.299-0.986 p = 0.045) levels with frailty status (being nonrobust) in regression models. DISCUSSION: In the study, it has been shown that pectoralis muscle assessment might be a related parameter to frailty in older women with breast cancer.

The effects of training, acute exercise and dietary fatty acid composition on muscle lipid oxidative capacity in European starlings.

Migratory birds undergo seasonal changes to muscle biochemistry. Nonetheless, it is unclear to what extent these changes are attributable to the exercise of flight itself versus endogenous changes. Using starlings (Sturnus vulgaris) flying in a wind tunnel, we tested the effects of exercise training, a single bout of flight and dietary lipid composition on pectoralis muscle oxidative enzymes and lipid transporters. Starlings were either unexercised or trained over 2 weeks to fly in a wind tunnel and sampled either immediately following a long flight at the end of this training or after 2 days recovery from this flight. Additionally, they were divided into dietary groups that differed in dietary fatty acid composition (high polyunsaturates versus high monounsaturates) and amount of dietary antioxidant. Trained starlings had elevated (19%) carnitine palmitoyl transferase and elevated (11%) hydroxyacyl-CoA dehydrogenase in pectoralis muscle compared with unexercised controls, but training alone had little effect on lipid transporters. Immediately following a long wind-tunnel flight, starling pectoralis had upregulated lipid transporter mRNA (heart-type fatty acid binding protein, H-FABP, 4.7-fold; fatty acid translocase, 1.9-fold; plasma membrane fatty acid binding protein, 1.6-fold), and upregulated H-FABP protein (68%). Dietary fatty acid composition and the amount of dietary antioxidants had no effect on muscle catabolic enzymes or lipid transporter expression. Our results demonstrate that birds undergo rapid upregulation of catabolic capacity that largely becomes available during flight itself, with minor effects due to training. These effects likely combine with endogenous seasonal changes to create the migratory phenotype observed in the wild.

Lack of variation in nuclear DNA content in avian muscle.

The avian pectoralis muscle demonstrates plasticity with regard to size, so that temperate birds facing winter conditions or birds enduring a migration bout tend to have significant increases in the size and mass of this tissue due to muscular hypertrophy. Myonuclear domain (MND), the volume of cytoplasm a myonuclei services, in the pectoralis muscle of birds seems to be altered during thermal stress or changing seasons. However, there is no information available regarding muscle DNA content or ploidy level within the avian pectoralis. Changes in muscle DNA content can be used in this tissue to aid in size and mass changes. Here, we hypothesized that long-distance migrants or temperate residents would use the process of endoreduplication to aid in altering muscle size. Mostly contradictory to our hypotheses, we found no differences in the mean muscle DNA content in any of the 62 species of birds examined in this study. We also found no correlations between mean muscle DNA content and other muscle structural measurements, such as the number of nuclei per millimeter of fiber, myonuclear domain, and fiber cross-sectional area. Thus, while avian muscle seems more phenotypically plastic than mammalian muscle, the biological processes surrounding myonuclear function may be more closely related to those seen in mammals.

Correlation of CT-derived pectoralis muscle status and COVID-19 induced lung injury in elderly patients.

OBJECTIVES: To explore the association between CT-derived pectoralis muscle index (PMI) and COVID-19 induced lung injury. METHODS: We enrolled 116 elderly COVID-19 patients linked to the COVID-19 outbreak in Nanjing Lukou international airport. We extracted three sessions of their CT data, including one upon admission (T1), one during the first 2 weeks when lung injury peaked (T2) and one on day 14 ± 2 (T3). Lung injury was assessed by CT severity score (CTSS) and pulmonary opacity score (POS). Pneumonia evolution was evaluated by changes of CT scores at T2 from T1(Δ). RESULTS: The maximum CT scores in low PMI patients were higher than those of normal PMI patients, including CTSS1 (7, IQR 6-10 vs. 5, IQR 3-6, p < 0.001), CTSS2 (8, IQR 7-11 vs. 5, IQR 4-7, p < 0.001) and POS (2, IQR 1-2.5 vs. 1, IQR 1-2, p < 0.001). Comorbidity (OR = 6.15, p = 0.023) and the presence of low PMI (OR = 5.43, p = 0.001) were predictors of lung injury aggravation with ΔCTSS1 > 4. The presence of low PMI (OR = 5.98, p < 0.001) was the predictor of lung injury aggravation with ΔCTSS2 > 4. Meanwhile, presence of low PMI (OR = 2.82, p = 0.042) and incrementally increasing D-dimer (OR = 0.088, p = 0.024) were predictors of lung injury aggravation with ΔPOS = 2. CONCLUSIONS: PMI can be easily assessed on chest CT images and can potentially be used as one of the markers to predict the severity of lung injury in elderly COVID-19 patients.

30 s sit-to-stand power is positively associated with chest muscle thickness in COVID-19 survivors.

INTRODUCTION: After hospitalization, early detection of musculoskeletal sequelae might help healthcare professionals to improve and individualize treatment, accelerating recovery after COVID-19. The objective was to determine the association between the 30s sit-to-stand muscle power (30s-STS) and cross-sectional area of the chest muscles (pectoralis) in COVID-19 survivors. METHOD: This cross-sectional study collected routine data from COVID-19 survivors one month after hospitalization: 1) a chest computed tomography (CT) scan and 2) a functional capacity test (30s-STS). The pectoralis muscle area (PMA) was measured from axial CT images. For each gender, patients were categorized into tertiles based on PMA. The 30s-STS was performed to determine the leg extension power. The allometric and relative STS power were calculated as absolute 30s-STS power normalized to height squared and body mass. The two-way ANOVA was used to compare the gender-stratified tertiles of 30s-STS power variants. RESULTS: Fifty-eight COVID-19 survivors were included (mean age 61.2 ± 12.9 years, 30/28 (51.7%/48.3%) men/women). The two-way ANOVA showed significant differences between the PMA tertiles in absolute STS power (p = .002) and allometric STS power (p = .001). There were no significant gender x PMA tertile interactions (all variables p > .05). The high tertile of PMA showed a higher allometric STS power compared to the low and middle tertile, p = .002 and p = .004, respectively. Absolute STS power and allometric STS power had a moderate correlation with the PMA, r = 0.519 (p < .001) and r = 0.458 (p < .001) respectively. CONCLUSION: The 30s-STS power is associated with pectoralis muscle thickness in both male and female COVID-19 survivors. Thus, this test may indicate global muscle-wasting and may be used as a screening tool for lower extremity functional capacity in the early stages of rehabilitation planning in COVID-19 survivors.

Filling the Upper Pole with the Pectoralis Major Muscle Flap in Profunda Femoris Artery Perforator Flap Breast Reconstruction.

Background and Objectives: Among many donor site options for autologous breast reconstruction, the use of the profunda femoris artery perforator (PAP) flap has become common in patients who are not suitable for the gold standard procedure, the deep inferior epigastric artery perforator flap. However, its limited volume has precluded its wide use in breast reconstruction. The aim of this report was to demonstrate the effectiveness of a method in which the anatomical position of the pectoralis major muscle was adjusted to augment the volume of the superior pole of the breast during PAP flap transfer. A comparison was made with a conventional PAP flap breast reconstruction. Materials and Methods: Fifty-nine consecutive cases where unilateral autologous breast reconstruction was performed using the vertically designed PAP flap were retrospectively reviewed. Conventional PAP flap transfer was performed in 36 patients (Group 1), and PAP flap transfer with pectoralis major muscle augmentation was performed in 23 patients (Group 2). Results: The patient satisfaction at 12 months postoperatively was statistically greater in Group 2, with the pectoralis major muscle augmentation, than in Group 1 [23/36 (64%) vs. 22/23 (96%), p = 0.005]. There were no significant differences in postoperative complication rates at the reconstructed site [2/36 (5.6%) vs. 0/23 (0%), p = 0.52]. Conclusions: Higher patient satisfaction could be achieved with pectoralis major muscle augmentation in PAP flap breast reconstruction without increasing the postoperative complication rate at the reconstructed site.

Detection of early changes in the muscle properties of the pectoralis major in breast cancer patients treated with radiotherapy using a handheld myotonometer.

OBJECTIVE: The primary aim was to investigate serial changes in the mechanical properties of the pectoralis major (PM), upper trapezius (UT), and sternoclavicular mastoid muscle (SCM) in breast cancer patients undergoing radiotherapy (RT) using a hand-held myotonometer. The secondary aims were to determine changes in subjective symptoms and to identify correlation with subjective results. DESIGN: A total of 42 breast cancer patients were enrolled in this longitudinal prospective study. Muscle properties of the PM, UT, and SCM were evaluated before RT, immediately after RT, and 4 months post-RT. Subjective symptom scales of pain and stiffness at rest/stretch of each muscle were evaluated. RESULTS: The PM showed significant side-to-side differences; the affected PM showed increased tone, stiffness, and decreased elasticity compared with the unaffected PM. The affected PM and UT showed significant time-dependent interactions. Stiffness of the affected PM at stretching was significantly higher 4 months post-RT than baseline. Only the tone and elasticity of the affected PM were correlated with subjective symptoms. CONCLUSION: In breast cancer patients who received RT after surgery, increased tone, stiffness, and decreased elasticity were observed in the affected PM compared with the unaffected side, which sustained four months post-RT. Change in muscle properties immediately after RT preceded subjective stiffness, which worsened significantly 4 months post-RT compared with baseline.

The "Shirt Pocket" Technique-An Alternative for Augmentation-Mastopexy.

Augmentation-mastopexy is a frequent procedure with high rates of early recurrence of breast ptosis, mainly after subglandular approach. The dual-plane techniques, based on the cranial dissection of the pectoralis, is the most used, but this plane does not cover the inferior pole of the breast. Then, the possibility of a downward dissection of the muscle seems to be more reasonable to retain the implant and improve postoperative results. This study aimed to review the anatomy of the pectoralis in cadavers and the use of its downward dissection to create a pocket for breast implant as a "shirt pocket." This maneuver was associated with a superior-based dermoglandular flap to overprotect the inferior pole. No complications were related in the postoperative period. The anatomic review showed that the "shirt pocket" is a safe option if done carefully. The technique demonstrated to be feasible and seemed to be effective, being another alternative to prevent early recurrence of breast ptosis in these procedures.

A Novel Model Incorporating Pectoralis Muscle Measures to Predict Mortality After Ventricular Assist Device Implantation.

BACKGROUND: We have previously demonstrated that pectoralis muscle mass and tissue attenuation obtained on preoperative CT scans were powerful predictors of mortality after left ventricular assist device implantation. In this analysis, we confirm our findings in a separate left ventricular assist device implantation cohort, and we present a novel, user-friendly mortality-prediction model incorporating these measures. METHODS AND RESULTS: Patients with chest CTs performed ≤ 3 months prior to left ventricular assist device implantation at University of Minnesota (n = 143) and Houston Methodist Hospital (n = 133) were identified. Unilateral pectoralis muscle mass indexed to body surface area (PMI) and attenuation (approximated by mean Hounsfield units) (PHUm) were measured on preoperative chest CT scans. To develop a prediction model incorporating pectoralis muscle measures, we implemented a cross-validated model-selection approach using Cox proportional hazards regression models. The final model included PHUm, PMI, African American race, creatinine, total bilirubin, body mass index, bridge to transplant, and presence or absence of contrast. Receiver-operating characteristic curves for 30-, 90- and 365-day survival were generated. The area under the curve for the model at 30, 90 and 365 days was 0.78, 0.76 and 0.76, respectively. CONCLUSIONS: The Minnesota Pectoralis Risk Score had favorable discrimination in this multicenter dataset. These skeletal-muscle measures appear to add important information to preoperative risk assessment.

Quantitative Pectoralis Muscle Area is Associated with the Development of Lung Cancer in a Large Lung Cancer Screening Cohort.

BACKGROUND: Studies have demonstrated an inverse relationship between body mass index (BMI) and the risk of developing lung cancer. We conducted a retrospective cohort study evaluating baseline quantitative computed tomography (CT) measurements of body composition, specifically muscle and fat area in a large CT lung screening cohort (CTLS). We hypothesized that quantitative measurements of baseline body composition may aid in risk stratification for lung cancer. METHODS: Patients who underwent baseline CTLS between January 1st, 2012 and September 30th, 2014 and who had an in-network primary care physician were included. All patients met NCCN Guidelines eligibility criteria for CTLS. Quantitative measurements of pectoralis muscle area (PMA) and subcutaneous fat area (SFA) were performed on a single axial slice of the CT above the aortic arch with the Chest Imaging Platform Workstation software. Cox multivariable proportional hazards model for cancer was adjusted for variables with a univariate p < 0.2. Data were dichotomized by sex and then combined to account for baseline differences between sexes. RESULTS: One thousand six hundred and ninety six patients were included in this study. A total of 79 (4.7%) patients developed lung cancer. There was an association between the 25th percentile of PMA and the development of lung cancer [HR 1.71 (1.07, 2.75), p < 0.025] after adjusting for age, BMI, qualitative emphysema, qualitative coronary artery calcification, and baseline Lung-RADS® score. CONCLUSIONS: Quantitative assessment of PMA on baseline CTLS was associated with the development of lung cancer. Quantitative PMA has the potential to be incorporated as a variable in future lung cancer risk models.