Effects of age and body mass index on breast characteristics: a cluster analysis

Can thoraco-abdominal organ boundaries be accurately determined from X-ray and anthropometric surface scans? Implications for body armour system coverage and design

To optimise soldier protection within body armour systems, knowledge of the boundaries of essential thoraco-abdominal organs is necessary to inform coverage requirements. However, existing methods of organ boundary identification are costly and time consuming, limiting widespread adoption for use on soldier populations. The aim of this study was to evaluate a novel method of using 3D organ models to identify essential organ boundaries from low dose planar X-rays and 3D external surface scans of the human torso. The results revealed that, while possible to reconstruct 3D organs using template 3D organ models placed over X-ray images, the boundary data (relating to the size and position of each organ) obtained from the reconstructed organs differed significantly from MRI organ data. The magnitude of difference varied between organs. The most accurate anatomical boundaries were the left, right, and inferior boundaries of the heart, and lateral boundaries for the liver and spleen. Visual inspection of the data demonstrated that 11 of 18 organ models were successfully integrated within the 3D space of the participant's surface scan. These results suggest that, if this method is further refined and evaluated, it has potential to be used as a tool for estimating body armour coverage requirements.

"Normal" breast dimensions in obese women-reference values and the effect of weight loss

BACKGROUND

Breast hypertrophy may cause significant suffering, such as back- and breast pain, painful shoulder groves, and eczemas. Furthermore, women with breast hypertrophy may have lower quality of life than women without breast hypertrophy. Although 50% of the women undergoing breast reduction in the US have body mass index (BMI) >30 kg/m2, the current standard of normality is based on studies focusing on women <40 years of age and BMIs <25 kg/m2. This study aimed to present reference values for breast measurements for women with obesity and to investigate the relationship between BMI loss and each breast measurement.

MATERIALS AND METHODS

One hundred and six women underwent laparoscopic Roux-en-Y gastric bypass in Gothenburg, Sweden. The participants' breast anthropometrics were measured before and after bariatric surgery and their perception of the skin on their breasts was measured using the Sahlgrenska Excess Skin Questionnaire.

RESULTS

Breast volume, sternal notch to nipple (SNN) distance, and ptosis increased significantly with increasing BMI. For instance, women with BMIs between 30-34.9 kg/m2 have a mean breast volume of approximately 770 ml, those with BMIs of 40-44.9 kg/m2 have approximately 1150 ml, and those with BMIs above 50 kg/m2 have approximately 1400 ml. Furthermore, the percent change in the respective breast measurements relative to percent BMI change can be predicted, for instance, with a 20% reduction in BMI, the breast volume, SNN-distance, and ptosis decrease by 25%, 4%, and 20% respectively.

CONCLUSIONS

This article presents the first standard of normality for breast anthropometrics in women with obesity and a model for predicting the change in breast anthropometrics relative to BMI.

CLINICAL TRIAL REGISTRATION

This is a longitudinal observation study, registered https://fou.nu/is/gsb/ansokan/49651, No: VGFOUGSB-49651. Trial registry name: "Överskottshud efter överviktskirurgi - dess utveckling samt behov och effekt av plastikkirurgi" ("Excess skin after bariatric surgery - its development and the need and effect of plastic surgery").

Useful Reduction Mammoplasty Technique in Oncoplastic Breast Surgery and Reconstruction

Background

A combination of the reduction mammoplasty technique and breast reconstruction allows surgeons to lift ptotic breasts through local flaps and skin reduction during surgery for breast cancer. This study presents a reliable course for the combination of partial and skin or nipple-sparing mastectomy with reduction-reconstruction surgery.

Methods

Fifty-seven patients underwent a partial mastectomy before reduction mammoplasty of both breasts during the same time period between 2014 and 2021 at our institution and thirteen patients underwent skin or nipple-sparing mastectomy, breast reconstruction with an extended latissimus dorsi flap or silicone implant, and aesthetic reduction mammoplasty of the contralateral breast during the same time period. Additional photos were obtained preoperatively, immediately after the operation, and at one, three, six, and twelve months postoperatively. Patient satisfaction was evaluated preoperatively and postoperatively and postoperative complications were noted.

Results

Among the patients who underwent a partial mastectomy, the mean age was 45.18 ± 11.05 years, the mean body mass index (BMI) was 26.74 ± 3.53 kg/m², and the mean preoperative right and left breast volumes were 663.85 (±28.12) cc and 664.34 (±37.13) cc, respectively, and the mean excised mass weight was 177.74 (±213.93) g. Among the patients who underwent a skin-sparing mastectomy, the mean age was 51.62 ± 8.96 years, the mean BMI was 26.91 ± 4.34 kg/m², and the mean preoperative right and left breast volumes were 624.17 (±98.52) cc and 562.31 (±80.81) cc, respectively, and the mean excised mass weight was 618.05 (±338.17) g. Four patients (5.3%) in the partial mastectomy group had fat necrosis. The mean patient satisfaction score was higher postoperatively in both groups.

Conclusion

Patients with breast cancer and large and/or ptotic breasts can successfully undergo reduction mammoplasty for both breasts immediately following partial mastectomy and nipple or skin-sparing mastectomy.

Verification of Usability of Medical Image Data Using Projective Photography for Designing Clothing for Breast Cancer Patients

Manufacturing a customized mastectomy bra, using medical images obtained for breast cancer treatment, could be suggested as an alternative instead of the anthropometric method. However, the breast shape of a medical image is deformed from the anthropometric method as the measurement posture is different between the anthropometric method for making clothes and the medical image. As a breast consists of adipose tissues and a few muscles without bones, there is a possibility that a bra can be manufactured if the volume is constant. Therefore, a hypothesis was established that the volume of the breast would be constant, even if the measurement methods were different. As a result of the comparison of 3D-SIM and PPM by MRI, 18 items could be measured simultaneously. Nine items showed differences according to the measurement method. The next step in the case of 3D-SIM was calculating the volume by separating the breast shape into a cone and a hemispherical shape; in the case of MRI, an ellipsoidal volume formula was applied. A t-test was performed on the results obtained, showing no significant difference. Therefore, it was proven that the volume of the breast does not change despite the difference in the measurement and the measurement method.

Estimation of the Surface Dose in Breast Irradiation by the Beam Incident Angle and the 1 cm Depth Dose

To develop a method of estimating surface dose in whole breast irradiation, we used an anthropomorphic phantom with accessories for the simulation of different breast sizes. The surface points, which are measured by TLDs, are set along with two main directions, superior-inferior and medial-lateral. The incident angle between the photon beam and the surface and the doses at 1 cm beneath the surface at every point are assessed by a computerized treatment planning system (cTPS). With the prescription dose of 200 cGy, the average surface doses under tangential irradiation are 97.73 (±14.96) cGy, 99.90 (±10.73) cGy, and 105.26 (±9.21) cGy for large, medium, and small breast volumes, respectively. The surface dose increased in the model of small breast volume without significance (p = 0.39). The linear analysis between surface dose and the incident angle is y = 0.5258x + 69.648, R² = 0.7131 (x: incident angle and y: surface dose). We develop the percentage of skin surface dose with reference to a depth of 1 cm (PSDR1cm) to normalize the inhomogeneous dose. The relationship between incident angle and PSDR1cm is y = 0.1894x + 36.021, R² = 0.6536 (x: incident angle and y: PSDR1cm) by linear analysis. In conclusion, the surface dose in whole breast irradiation could be estimated from this linear relationship between PSDR1cm and incident angle in daily clinical practice by cTPS. Further in vivo data should be studied to verify this formula.

Effect of Torso and Breast Characteristics on the Perceived Fit of Body Armour Systems Among Female Soldiers: Implications for Body Armour Sizing and Design

This study aimed to provide normative data characterising the torsos and breasts of female soldiers and to determine which torso and breast anthropometric measurements contributed to reports of poor body armour fit. Ninety-seven female Australian Army soldiers completed a questionnaire about their experience with current-issue body armour, including perceptions of fit. Participants also attended a single testing session where we took a three-dimensional scan of their breasts and torso and collected several anthropometric measurements to characterise their torso size and shape. Sixteen of the 22 breast and torso measurements collected were significantly related to the perceived fit of current-issue body armour systems. To improve perceptions of fit for female soldiers and, in turn, reduce movement interference, discomfort, and barriers to occupational performance, future body armour systems should cater to the wide range of female breast and torso shapes and sizes.

Women with larger breasts are less satisfied with their breasts: Implications for quality of life and physical activity participation

Introduction:

Although low breast satisfaction has been associated with a range of potential negative health implications, little is known about key factors that influence breast satisfaction across the lifespan. This study aimed to determine the impacts of age, body mass and breast size on breast satisfaction and how breast satisfaction impacts psychosocial and sexual well-being-related quality of life outcomes and physical activity behaviours.

Methods:

Three hundred and forty-five women (age range: 18.1–83.7 years) had their body mass (kg), standing height (cm) and breast volume (ml) measured. A 13-item questionnaire comprising the Breast-Q and Active Australia Survey was used to assess breast satisfaction, quality of life outcomes and participation in physical activity.

Results:

Breast satisfaction was influenced by breast size, such that women with larger breasts were less satisfied with their breasts compared to their counterparts with smaller breasts. Greater breast satisfaction was associated with improved psychosocial and sexual well-being-related measures of quality of life, and time spent participating in physical activity.

Conclusion:

Interventions to improve breast satisfaction among women across the breast size spectrum should be encouraged in public health initiatives to better engage and encourage positive health behaviours and reduce potential adverse health implications.

Bra-body armour integration, breast discomfort and breast injury associated with wearing body armour

This study investigated whether female soldiers experience bra integration or breast discomfort/injuries related to body armour use and whether these issues were associated with breast size. Ninety-seven Australian Defence Force female soldiers completed a questionnaire and had their breast volume assessed (range: 91-919 ml/breast) using three-dimensional scanning. Twenty-two percent (n = 21) of participants reported integration issues between their bra and body armour, 63% (n = 61) reported breast discomfort while wearing body armour and 27% (n = 26) reported experiencing a breast injury related to wearing body armour. Although bra-body armour integration was not dependent upon breast size, female soldiers with medium-large breasts reported significantly more breast discomfort and injuries when using body armour compared to participants with small breasts. These findings highlight the importance of developing body armour systems that cater to the range of breast sizes of female soldiers in order to improve bra-body armour integration and reduce breast discomfort and injury. Practitioner summary: This exploratory research provides evidence of bra integration issues, breast discomfort and breast injury experienced by female soldiers when wearing body armour. Given the growing representation of women in military organisations, strategies to alleviate these issues for female users of body armour, particularly those with larger breast sizes, are required.

The evolution of perennially enlarged breasts in women: a critical review and a novel hypothesis

The possession of permanent, adipose breasts in women is a uniquely human trait that develops during puberty, well in advance of the first pregnancy. The adaptive role and developmental pattern of this breast morphology, unusual among primates, remains an unresolved conundrum. The evolutionary origins of this trait have been the focus of many hypotheses, which variously suggest that breasts are a product of sexual selection or of natural selection due to their putative role in assisting in nursing or as a thermoregulatory organ. Alternative hypotheses assume that permanent breasts are a by-product of other evolutionary changes. We review and evaluate these hypotheses in the light of recent literature on breast morphology, physiology, phylogeny, ontogeny, sex differences, and genetics in order to highlight their strengths and flaws and to propose a coherent perspective and a new hypothesis on the evolutionary origins of perennially enlarged breasts in women. We propose that breasts appeared as early as Homo ergaster, originally as a by-product of other coincident evolutionary processes of adaptive significance. These included an increase in subcutaneous fat tissue (SFT) in response to the demands of thermoregulatory and energy storage, and of the ontogenetic development of the evolving brain. An increase in SFT triggered an increase in oestradiol levels (E2). An increase in meat in the diet of early Homo allowed for further hormonal changes, such as greater dehydroepiandrosterone (DHEA/S) synthesis, which were crucial for brain evolution. DHEA/S is also easily converted to E2 in E2-sensitive body parts, such as breasts and gluteofemoral regions, causing fat accumulation in these regions, enabling the evolution of perennially enlarged breasts. Furthermore, it is also plausible that after enlarged breasts appeared, they were co-opted for other functions, such as attracting mates and indicating biological condition. Finally, we argue that the multifold adaptive benefits of SFT increase and hormonal changes outweighed the possible costs of perennially enlarged breasts, enabling their further development.

Breast Biomechanics: What Do We Really Know?

Although half the world's population will develop breasts, there is limited research documenting breast structure or motion. Understanding breast structure and motion, however, is imperative for numerous applications, such as breast reconstruction, breast modeling to better diagnose and treat breast pathologies, and designing effective sports bras. To be impactful, future breast biomechanics research needs to fill gaps in our knowledge, particularly related to breast composition and density, and to improve methods to accurately measure the complexities of three-dimensional breast motion. These methods should then be used to investigate breast biomechanics while individuals, who represent the full spectrum of women in the population, participate in a broad range of activities of daily living and recreation.

The impact of age and body mass index on a bra sizing system formed by anthropometric measurements of Sichuan Chinese females

Existing bra sizing systems are based only on bust and underbust girths, which do not guarantee an accurate fit or comfort for consumers. This study presents a comprehensive investigation of the impact of age and body mass index (BMI) on bra sizing systems, and the distributions of band and cup sizes based on anthropometric measurement data. The first four principal components were extracted by principal component analysis, and the factor loadings of age and BMI were found to be significant determinants of bra size along with 12 other variables. Furthermore, chi-square analysis revealed that bra size allocations were significantly influenced by age and BMI. Thus, we propose that age and BMI should be considered as auxiliary criteria for the bra sizing system. Taken together, these findings will be of value to designers and bra manufacturers in developing well-fitting bras for their target consumers, and to consumers for selecting well-fitting bras with confidence. Practitioner Summary: This study contributes to an understanding of how bra sizing systems are affected by age and BMI. This understanding is valuable to bra designers, manufacturers, and retailers, as it will enable the adjustment of bra sizes for different target markets and in turn improve consumer confidence in selecting proper fitting and comfortable bras.

Biomechanics of Breast Support for Active Women

More systematic breast biomechanics research and better translation of the research outcomes are necessary to provide information upon which to design better sports bras and to develop effective evidence-based strategies to alleviate exercise-induced breast pain for women who want to participate in physical activity in comfort.

Association between body mass index and localization of breast cancer: results from a nationwide inpatient database in Japan

PURPOSE

Although both localization of breast cancer and body mass index (BMI) are associated with prognosis, the association between localization of breast cancer and BMI remains unclear. This study aimed to investigate the association between localization of breast cancer and BMI at diagnosis.

METHODS

Patients who underwent surgery for stage 0-III breast cancer July 2010-March 2017 were identified retrospectively in a Japanese nationwide inpatient database. Multinomial logistic regression analyses adjusting for patient's age were conducted to compare the outcomes among five BMI groups: < 18.5 kg/m² (n = 31,724; 9.3%), 18.5-24.9 kg/m² (n = 218,244; 64.3%), 25.0-29.9 kg/m² (n = 69,813; 20.6%), 30.0-34.9 kg/m² (n = 16,052; 4.7%), and ≥ 35.0 kg/m² (n = 3716; 1.1%). The outcomes were the quadrant and side of the breast where tumors were detected.

RESULTS

In total, about half of the patients had breast cancer in the upper-outer quadrant (49.7%) and in the left breast (51.1%). In the multinomial analysis, BMI ≥ 25.0 kg/m² was associated with the occurrence of breast cancer in the upper-inner and lower-outer quadrants and in the central area, whereas BMI < 18.5 kg/m² was associated with the occurrence of breast cancer in the central area only. The side of breast cancer did not differ significantly among the five BMI groups.

CONCLUSIONS

Localization of breast cancer was associated with BMI in this large nationwide cohort. The findings may benefit patients' self-checks and doctors' examinations, potentially resulting in early detection and treatment.

Breast and torso characteristics of female contact football players: implications for the design of sports bras and breast protection

This study aimed to provide normative data characterising the breast size, breast position and torso size of female contact football players. 117 AFL, Rugby League, Rugby Union and Rugby 7s players attended a single testing session where a three-dimensional scan was taken of their naked breasts and torso. Dimensions relevant to the design of sports bras and breast protective equipment were then calculated from the scans. Several breast and torso characteristics of female contact football athletes differed to measurements reported for females in the general population and amongst the contact football codes. Designers and manufacturers of sports bras or breast protective equipment should consider the specific breast and torso dimensions of female contact football players to maximise the fit, comfort and efficacy of these garments. Practitioner summary: Using three-dimensional scanning, this study characterised the breast and torso size and shape of 117 female contact football players. These normative data should be used to improve the fit and comfort of sports bras and breast protective equipment for female contact football players.

The Attachments of the Breast to the Chest Wall: A Dissection Study

BACKGROUND

The anatomical descriptions of the attachments of the female breast to the chest wall vary in their structure, location, and terminology within the published literature.

METHODS

A dissection study of the attachments of the breast to the chest wall was conducted on 18 female embalmed breasts in the coronal (n = 15) and sagittal planes (n = 3).

RESULTS

Perimeter, posterior wall, and horizontal septum attachments were observed. The perimeter along its entire length was attached to the chest wall. Regional and anatomical variation was observed in this structure and location. Sharp dissection was required to remove it from the chest wall, in contrast to the blunt dissection required to remove the posterior wall and horizontal septum attachments.

CONCLUSIONS

The breast attaches to the chest wall along its entire perimeter, posterior wall, and horizontal septum, with the perimeter functioning as the primary anchor of the breast to the chest wall. The structure of the perimeter attachment is both periosteal and fascial and requires sharp dissection to remove it from the chest wall. The fascial structures of the posterior wall and horizontal septum require blunt dissection only. The structure of the perimeter has regional variation, and its location on the chest wall has anatomical variation. Detailed anatomical descriptions and illustrations are supported by photographic evidence of cadaver dissections in two planes. Clinical and anatomical terminology are linked, with clinical implications for medical anatomy education, breast modeling, and breast surgery.

Undergarment needs after breast cancer surgery: a key survivorship consideration

An important aspect of breast cancer survivorship is finding comfortable undergarments that work for women's post-treatment bodies. Patients who undergo mastectomy, including both those who do and do not receive reconstruction, need bras that can accommodate new breast shape, size, and feel, as well as scarring and skin sensitivity. Our research with breast cancer patients and the literature reveal that ready-to-wear bras are inadequate for the variety of patients' needs, and many women lack support and guidance to make decisions about undergarments after cancer. This commentary describes a major quality-of-life challenge for breast cancer survivors and makes recommendations for future research. Healthcare providers need more guidance and resources to be able to help their patients prepare for this aspect of survivorship. New technologies, such as biomechanical modeling, 3D body scanning, and manufacturing techniques, should be pursued in collaboration with patients, healthcare providers, and clothing designers to ease this burden for breast cancer patients.

Effects of obesity on breast size, thoracic spine structure and function, upper torso musculoskeletal pain and physical activity in women

PURPOSE

This study investigated the effects of obesity on breast size, thoracic spine structure and function, upper torso musculoskeletal pain and physical activity participation in women living independently in the community.

METHODS

A total of 378 women were divided into 3 groups (Not Overweight: body mass index (BMI) = 22.5 ± 0.2 kg/m² (mean ± SE); Overweight: BMI = 27.4 ± 0.3 kg/m²; Obese: BMI = 35.4 ± 0.3 kg/m²). Outcome variables of breast volume (mL), thoracic flexion torque (N·m), thoracic kyphosis (degrees), upper torso musculoskeletal pain (score) and time spent in physical activity (min) were calculated and compared among the 3 groups, adjusting for between-group differences in age.

RESULTS

There was a significant main effect of BMI on all outcome variables. Participants classified as Obese displayed significantly larger breasts, had greater thoracic flexion torques and reported less time participating in physical activity relative to the participants who were classified as Not Overweight and Overweight. Participants in the Obese group also displayed significantly more thoracic kyphosis and reported significantly more upper torso musculoskeletal pain compared to their counterparts who were classified as Not Overweight.

CONCLUSION

This study is the first to demonstrate that increased obesity levels were associated with compromised kyphosis and loading of the thoracic spine, as well as increased symptoms of upper torso musculoskeletal pain and reduced time spent in physical activity in women living in the community. We recommend further research to determine whether evidence-based interventions designed to reduce the flexion torque generated on the thoracic spine can improve these symptoms of upper torso musculoskeletal pain and the ability of women with obesity to participate in physical activity.