Factors that influence the administration of tranexamic acid (TXA) to trauma patients in prehospital settings: a systematic review.

OBJECTIVE: In the UK there are around 5400 deaths annually from injury. Tranexamic acid (TXA) prevents bleeding and has been shown to reduce trauma mortality. However, only 5% of UK major trauma patients who are at risk of haemorrhage receive prehospital TXA. This review aims to examine the evidence regarding factors influencing the prehospital administration of TXA to trauma patients. DESIGN: Systematic literature review. DATA SOURCES: AMED, CENTRAL, CINAHL, Cochrane Database of Systematic Reviews, Conference Proceedings Citation Index-Science, Embase and MEDLINE were searched from January 2010 to 2020; searches were updated in June 2022. CLINICALTRIALS: gov and OpenGrey were also searched and forward and backwards citation chasing performed. ELIGIBILITY CRITERIA: All primary research reporting factors influencing TXA administration to trauma patients in the prehospital setting was included. DATA EXTRACTION AND SYNTHESIS: Two independent reviewers performed the selection process, quality assessment and data extraction. Data were tabulated, grouped by setting and influencing factor and synthesised narratively. RESULTS: Twenty papers (278 249 participants in total) were included in the final synthesis; 13 papers from civilian and 7 from military settings. Thirteen studies were rated as 'moderate' using the Effective Public Health Practice Project Quality Assessment Tool. Several common factors were identified: knowledge and skills; consequences and social influences; injury type (severity, injury site and mechanism); protocols; resources; priorities; patient age; patient sex. CONCLUSIONS: This review highlights an absence of high-quality research. Preliminary evidence suggests a host of system and individual-level factors that may be important in determining whether TXA is administered to trauma patients in the prehospital setting. FUNDING AND REGISTRATION: This review was supported by Research Capability Funding from the South Western Ambulance Service NHS Foundation Trust and the National Institute for Health Research Applied Research Collaboration South West Peninsula. PROSPERO REGISTRATION NUMBER: CRD42020162943.

Factors influencing conveyance of older adults with minor head injury by paramedics to the emergency department: a multiple methods study.

BACKGROUND: Head injury (HI) in older adults due to low-energy falls result in a substantial number of emergency department (ED) attendances. However, mortality associated with minor HI is very low. Reducing conveyance to hospital is important for older adults and is a priority for the National Health Service (NHS). Therefore, paramedics are required to make accurate decisions regarding conveyance to the ED. This study used routine data and semi-structured interviews to explore the factors that influence paramedic decision-making when considering whether to convey an adult aged 65 years and over with a minor HI to the ED. METHODS: Semi-structured telephone interviews were completed with ten UK paramedics from a single EMS (ambulance) provider organisation. Interviews explored the factors influencing the paramedics' conveyance decision-making in adults aged 65 years and over with a minor HI. Data were initially analysed inductively to develop a thematic framework. A retrospective analysis of ambulance service data was also completed to determine the scope and scale of the issue in Southwest England. An in-depth audit of 100 conveyed patient records was used to determine the proportion of patients conveyed to the ED who met National Institute for Health and Care Excellence (NICE) and Joint Royal Colleges Ambulance Liaison Committee (JRCALC) guidelines. RESULTS: In 2019 South Western Ambulance Service NHS Foundation Trust (SWASFT) attended 15,650 emergency calls to patients aged 65 and over with minor HI, with 70.5% conveyed to ED. 81% of conveyed patients met NICE and JRCALC guideline criteria for conveyance, with the remainder conveyed due to wound care or other medical concerns. The framework developed from the interviews comprised four themes: resources; patient factors; consequences; paramedic factors. Important factors included: the patient's social situation; guidelines; clinical support availability; the history and presentation of the patient; risk. CONCLUSION: This study examined paramedic conveyance decisions for older people with minor HI. It identified multiple influencing factors, highlighting the complex nature of these decisions, and may serve as a basis for developing an intervention to safely decrease ED conveyance in this patient group.

Ligamentum Teres Lesions Are Associated With Poorer Patient Outcomes in a Large Primary Hip Arthroscopy Cohort of 1,935 Patients.

Purpose: To retrospectively evaluate the prevalence and characteristics of ligamentum teres (LT) lesions identified in a single-surgeon hip arthroscopy cohort and to compare surgical outcomes of those with, and without, identified LT lesions. Methods: Patients who underwent primary hip arthroscopy between 2005 and 2018 in one surgeon's clinic were identified. Those with a history involving extra-articular scoping or any previous surgery on the ipsilateral hip were excluded. Patient-reported outcome measures completed before and after surgery included the Hip Disability and Osteoarthritis Outcome Score, Nonarthritic Hip Score, and 12-item International Hip Outcome Tool. Conversion to hip joint replacement was ascertained through a national register. Results: A total of 1,935 primary hip arthroscopies (from 1,607 different patients) were included in this study. In total, 323 LT lesions were identified. Those with LT lesions were older than those without (40.3 ± 11.3 years compared with 33.9 ± 12.1 years; P < .001), and more frequently female (58.2% vs 41.8%; P = .001). Hips with lesions had a smaller lateral center-edge angle than other hips (33.0 ± 6.8° vs 34.1 ± 6.0°; P = .004). All patient-reported outcome measures improved significantly (P < .001) from pre- to post-surgery for patients with and without LT lesions. However, patients with LT lesions reported less improvement in the 12-item International Hip Outcome Tool (difference -5.60; P = .004) and in Hip Disability and Osteoarthritis Outcome Score symptoms (-4.41; P = .004), sports (-7.81; P < .001), and quality of life subscales (-8.85; P < .001) than those without lesions. Hips with LT lesions also had a 6.2% 2-year rate of subsequent hip replacement (20/323 hips) compared with those without lesions (0.9%; 14/1612 hips; P < .001). Conclusions: In this single-surgeon hip arthroscopy cohort, identification of LT lesions was associated with poorer patient-reported outcomes and increased likelihood of conversion to arthroplasty within 2 years. These findings suggest a poorer prognosis for patients with LT injury compared with those without. Level of Evidence: Level III, retrospective cohort study.

Medical students' experience of studying while working part-time and the effects of COVID-19.

AIMS: The costs of being a medical student are large and increasing, and many students need to work part-time to meet financial pressures. This study explores the impact that part-time extracurricular paid work during the academic year has on medical student wellbeing, their interactions with the curriculum, and the effect of COVID-19 on work in 2020. METHODS: An online survey in 2020 gathered demographic, quantitative and qualitative information from medical students and their work experiences. Descriptive statistics analysed quantitative data; qualitative data were analysed using qualitative content analysis. RESULTS: Of the 36% (n=530) of students who responded, 255 (49%) reported undertaking paid part-time work, with 59 (24%) reporting they would not be able to remain studying if they did not work. When interacting with the medical programme, 43% of students reported their work conflicted with scheduled medical school commitments, and 70% reported conflicts between work and individual study. COVID-19 disrupted 57% of paid work during the year. Impacts on students' wellbeing were both positive and negative. Positive aspects included developing new skills, self-confidence and resilience. Working also provided an escape from the study demands of the medical programme. Negative aspects were predominantly about the increased stress working had on students, specifically on the impact of paid work on their own health. CONCLUSIONS: Almost half of medical students work part-time while studying. Understanding the perceived implications that part-time work has on student education and wellbeing could help medical schools provide appropriate advice and pastoral support for their students.

The morphology of the subacromial and related shoulder bursae. An anatomical and histological study.

Shoulder bursae are essential for normal movement and are also implicated in the pathogenesis of shoulder pain and dysfunction. The subacromial bursa (SAB), within the subacromial space, is considered a primary source of shoulder pain. Several other bursae related to the subcoracoid space, including the coracobrachial (CBB), subcoracoid (SCB) and subtendinous bursa of subscapularis (SSB), are also clinically relevant. The detailed morphology and histological characteristics of these bursae are not well described. Sixteen embalmed cadaveric shoulders from eight individuals (five females, three males; mean age 78.6 ± 7.9 years) were investigated using macro-dissection and histological techniques to describe the locations, dimensions and attachments of the bursae, their relationship to surrounding structures and neurovascular supply. Bursal sections were stained with haematoxylin and eosin to examine the synovium and with antibodies against von Willebrand factor and neurofilament to identify blood vessels and neural structures respectively. Four separate bursae were related to the subacromial and subcoracoid spaces. The SAB was large, with a confluent subdeltoid portion in all except one specimen, which displayed a distinct subdeltoid bursa. The SAB roof attached to the lateral edge and deep surface of the acromion and coracoacromial ligament, and the subdeltoid fascia; its floor fused with the supraspinatus tendon and greater tubercle. The CBB (15/16 specimens) was deep to the conjoint tendon of coracobrachialis and short head of biceps brachii and the tip of the coracoid process, while the inconstant SCB (5/16 specimens) was deep to the coracoid process. Located deep to the subscapularis tendon, the SSB was a constant entity that commonly displayed a superior extension. Synovial tissue was predominantly areolar (SAB and SSB) or fibrous (CBB and SCB), with a higher proportion of areolar synovium in the bursal roofs compared to their floors. Blood vessels were consistently present in the subintima with a median density of 3% of the tissue surface area, being greatest in the SSB and SAB roofs (4.9% and 3.4% respectively) and least in the SAB floor (1.8%) and CBB roof and floor (both 1.6%). Nerve bundles and free nerve endings were identified in the subintima in approximately one-third of the samples, while encapsulated nerve endings were present in deeper tissue layers. The extensive expanse and attachments of the SAB support adoption of the term subacromial-subdeltoid bursa. Morphologically, the strong attachments of the bursal roofs and floors along with their free edges manifest as fixed and mobile portions, which enable movement in relation to surrounding structures. The presence of neurovascular structures demonstrates that these bursae potentially contribute blood supply to surrounding structures and are involved in mechanoreception. The anatomical details presented in this study clarify the morphology of the shoulder bursae, including histological findings that offer further insight into their potential function.

Barriers and facilitators to the administration of prehospital tranexamic acid: a paramedic interview study using the theoretical domains framework.

BACKGROUND: Tranexamic acid (TXA) is an antifibrinolytic drug used to prevent bleeding. It was introduced as an intervention for post-traumatic haemorrhage across emergency medical services (EMS) in the UK during 2012. However, despite strong evidence of effectiveness, prehospital TXA administration rates are low. This study used the theoretical domains framework (TDF) to identify barriers and facilitators to the administration of TXA to trauma patients by EMS providers (paramedics) in the UK. METHODS: Interviews were completed with 18 UK paramedics from a single EMS provider organisation. A convenience sampling approach was used, and interviews continued until thematic saturation was reached. Semistructured telephone interviews explored paramedics' experiences of administering TXA to trauma patients, including identifying whether or not patients were at risk of bleeding. Data were analysed inductively using thematic analysis (stage 1). Themes were mapped to the theoretical domains of the TDF to identify behavioural theory-derived barriers and facilitators to the administration of TXA to trauma patients (stage 2). Belief statements were identified and assessed for importance according to prevalence, discordance and evidence base (stage 3). RESULTS: Barriers and facilitators to paramedics' administration of TXA to trauma patients were represented by 11 of the 14 domains of the TDF. Important barriers included a lack of knowledge and experience with TXA (Domain: Knowledge and Skills), confusion and restrictions relating to the guidelines for TXA administration (Domain: Social/professional role and identity), a lack of resources (Domain: Environmental context and resources) and difficulty in identifying patients at risk of bleeding (Domain: Memory, attention and decision processes). CONCLUSIONS: This study presents a behavioural theory-based approach to identifying barriers and facilitators to the prehospital administration of TXA to trauma patients in the UK. It identifies multiple influencing factors that may serve as a basis for developing an intervention to increase prehospital administration of TXA.

From physiotherapy to the army: negotiating previously developed professional identities in mature medical students.

Professional identity formation, the process of transformation from lay person to doctor, is at the heart of medical education. Medical student cohorts can include students who enter medicine from a previous career, i.e. with developed professional identities and who are usually older and more mature. Students with previously developed professional identities may have specific challenges in negotiating their new 'doctor' identity. This study examined the development of professional identity in mature medical students who had a variety of previous careers prior to entering medical school. A narrative inquiry was undertaken using interviews of mature medical students with backgrounds that included physiotherapy, clinical physiology, public health and nutrition, and the armed forces. A narrative analysis was conducted combining both thematic and structural perspectives using linguistics and positioning theory as interpretive tools. Three main themes emerged that portray the development processes that arise in this cohort as they develop their medical professional identity: holding back aspects of the previous self; foregrounding aspects of the previous self; and developing new aspects towards forming a 'new' self. These themes and their implications are discussed in the context of current literature, highlighting some of the specific challenges that this cohort faces in developing their medical identity. We argue that dedicated faculty and student development be offered, exploring how professional identity formation in mature medical students can be facilitated and supported, so staff and students are better equipped to engage and shape mature students' professional identity in a meaningful way.

Load-deformation properties of the ligament of the head of femur in situ.

The ligament of the head of femur (LHF) or ligamentum teres has been reported to tense during hip adduction and also to provide mechanical stability to the joint. LHF injury is more common in females and also in right hip joints compared with left ones. Although this could be due to leg dominance, pelvic size or muscle strength, there is no study that has looked into these differences. This cadaveric biomechanical study aimed to compare potential differences in the mechanical behavior of the LHF between neutral and 20° adducted hip joints, sex, and sides. Tensile tests of the LHF were performed on 25 hip joints (mean age at death of 85.7 ± 7.5 years; 9 females, 4 males; 13 left, 12 right), positioned either neutrally or in adduction. The maximum force required to rupture the ligament, its strain at failure, tensile strength, linear stiffness, and elastic modulus were obtained and statistically compared between analysis groups. The maximum force the LHF could withstand before rupture averaged 57 ± 37 N, strain at failure of 59 ± 33%, tensile strength of 2.9 ± 1.8 MPa, linear stiffness of 5.4 ± 3.5 N/mm, and elastic modulus of 7.2 ± 3.8 MPa. The LHF length at failure was significantly greater in males compared with females (P = 0.02). Irrespective of joint position, there were no statistical differences in the stress-strain properties of the LHF between females and males, or sides. There may be other anatomical, functional, and demographic factors that could render the ligament tissue vulnerable to injury in these groups. Clin. Anat., 33:705-713, 2020. © 2019 Wiley Periodicals, Inc.

A history of fascia.

Fascia is a generic anatomical term that refers to a variety of the body's soft fibrous connective tissue parts. An expanding interdisciplinary interest in fascia might be accompanied by changes in how fascia is cognized. This study surveys the anatomical portrayal of fascia through history, with the aim of helping contextualize the ways it is now known. A historiographic review of fascia-related literature written in the English language was undertaken. The anatomical meaning associated with fascia has varied during the 400 years that this term has been incorporated in English-language medical literature. Fascia has been diversely portrayed as a range of macroscopically discernable body parts, the tissues they are composed of, and a pervasive soft connective tissue network structure. Over the last four centuries, fascia has been described in many ways. Anatomical understanding of fascia has developed over the years and is likely to continue to change with evolving research technologies. Multidisciplinary advances in fascial knowledge could conceivably contribute to improving individual and societal health care. Clin. Anat. 32:862-870, 2019. © 2019 Wiley Periodicals, Inc.

Neurovascular structures of the ligament of the head of femur.

The ligament of the head of femur (LHF), or ligamentum teres, is believed to provide blood supply to the head of femur and mechanical stability to the hip joint. But these functions in the adult are often debated. The existence and distribution of neurovascular structures within the ligament are not widely documented. This study examined the blood vessels and nervous tissue within the LHF to determine whether the ligament may have a vascular and proprioceptive function at the hip joint. Histological sections from the LHF from 10 embalmed hips (six female, four male; mean age 80.4 ± 8.7 years) were cut at three levels: the foveal attachment, mid-length and its base where it attaches to the transverse acetabular ligament. Sections were stained with haematoxylin and eosin to study general tissue architecture or with von Willebrand factor and neurofilament to identify blood vessels and nervous tissue, respectively. The proportion of the ligament's cross-sectional area occupied by blood vessels was expressed as a vascularity index (VI). Nerve endings within the ligament were identified and morphologically classified. Comparisons between the VI at the three levels, or between the tissue layers of the ligament, were made using 95% confidence intervals; statistical significance was set P < 0.05. The ligament tissue comprised three distinct layers: a synovial lining with cuboidal cells, a sub-synovial zone formed of loose connective tissue and the ligament proper composed of dense collagen bundles. Patent blood vessels and nerve fibres were present both in the sub-synovial zone and the ligament proper; Pacinian corpuscles and free nerve endings were found scattered only in the sub-synovial zone. The VI of the ligament proper at the fovea was significantly higher than its middle (P = 0.01) and basal levels (P = 0.04); it was also higher than that of the sub-synovial layer (P = 0.04). The LHF has three histologically distinct zones, and blood vessels and nerves are distributed both in the sub-synovial layer and ligament proper. Higher vascularity within the ligament proper at its foveal insertion suggests a possible nutritive role of the LHF to the adult head of femur. The presence of nerves and nerve receptors indicates the ligament is involved in the perception of pain and proprioception, thereby contributing to mechanical stability of the joint.

Clinical Anatomy of the Ligament of the Head of Femur.

The ligament of the head of femur (LHF) has gained clinical attention recently and is reported to contribute to hip stability. This study explores its morphology and morphometry, information that may help inform surgical decision making. Gross anatomical dissections were undertaken on 229 embalmed hips from European (n = 105) and Thai (n = 124) adult cadavers to examine LHF anatomy. Ligament morphometry was statistically compared at different sites, between sexes and sides. The origin of ligamental arteries and absence of the ligament were documented. The LHF was pyramidal or quadrangular in shape. Sub-synovial fibrous bands originated from the transverse acetabular ligament, edges of the acetabular notch, and acetabular floor; less frequently from the hip joint capsule. Distally, the ligament flattened and converged onto the fovea capitis. The ligament was 22.3 ± 4.4 mm long and was significantly wider (P = 0.001) and thicker (P = 0.0003) at the fovea, compared to its mid-zone. Branches of the obturator artery entered the acetabular foramen inferomedially and penetrated the middle third of the LHF. Blood vessels ran within the LHF and appeared to enter the fovea. The ligament was absent in 2.8% of Thai hips and there were no significant sex or side differences in ligament dimensions. The morphology of the LHF is complex. While individual variation was apparent, blood vessels were seen in the distal ligament. Precise information on LHF morphometry and attachment sites will help inform appropriate graft dimensions and choice of fixation sites necessary for ligament reconstruction. Clin. Anat., 2018. © 2018 Wiley Periodicals, Inc. Clin. Anat., 2018. © 2018 Wiley Periodicals, Inc.

Role of activin C in normal ovaries and granulosa cell tumours of mice and humans.

Activins and inhibins play important roles in the development, growth and function of the ovary. Mice lacking inhibin develop granulosa cell tumours in their ovaries that secrete activin A, and these tumours are modulated by increased activin C expression. The aim of the present study was to identify where activin C is expressed in mouse and human ovaries and whether overexpression of activin C modulates normal follicular development in mice. Immunohistochemical staining for the activin ßC subunit was performed on sections from mouse and human ovaries and human adult granulosa cell tumours. Stereology techniques were used to quantify oocyte and follicular diameters, and the percentage of different follicular types in ovaries from wild-type mice and those underexpressing inhibin α and/or overexpressing activin C. Staining for activin ßC was observed in the oocytes, granulosa cells, thecal cells and surface epithelium of mouse and human ovaries, and in the granulosa-like cells of adult granulosa cell tumours. Overexpression of activin C in mice did not alter follicular development compared with wild-type mice, but it did modulate the development of abnormal early stage follicles in inhibin α-null mice. These results provide further evidence of a role for activin C in the ovary.

What do medical students learn from dissection?

Dissection has long been the accepted method for teaching anatomy to medical students. More recently, some educators have suggested that easier, cheaper, alternative methods are just as effective. But what do the students think? This paper aimed to identify what undergraduate medical students learn, how they cope, and what effects participating in dissection has on them as individuals. A cohort of 267 second year medical students at Otago Medical School were invited to complete three online surveys; before their first dissection laboratory class, after their first musculoskeletal system dissection and following the last semester of studying anatomy. Open-ended questions showcasing the attitudes, beliefs, and opinions on what dissection had taught the medical students over years two and three were analyzed. A general inductive approach was used and common emergent themes were identified. In total, 194 students completed the second, and 108 students completed the third questionnaire. Students commonly conveyed dissection as an appropriate and valuable educational tool, useful for teaching and learning anatomical knowledge and relationships, appreciating the body in three-dimension, teamwork, and how to cope with death/dead bodies. The noted effects of personal growth while participating in dissection were highly varied, but in general, impacted positively on the majority of students. This study shows that at Otago Medical School the students also believe that dissection is not only a useful tool to learn anatomy but also that it fosters teamwork, assists professional development and helps them come to terms with death and dying. Anat Sci Educ 11: 325-335. © 2017 American Association of Anatomists.

Do longus capitis and colli really stabilise the cervical spine? A study of their fascicular anatomy and peak force capabilities.

BACKGROUND: Longus capitis and colli are proposed to play a role in stabilising the cervical spine, targeted in clinical and research practice with cranio-cervical flexion. However, it is not clear if these muscles are anatomically or biomechanically suited to a stabilising role. OBJECTIVES: To describe the fascicular morphology of the longus capitis and colli, and estimate their peak force generating capabilities across the individual cervical motion segments. STUDY DESIGN: Biomechanical force modelling based on anatomical data. METHODS: Three-part design including cadaveric dissection (n = 7), in vivo MRI muscle volume calculation from serial slices in young healthy volunteers (n = 6), and biomechanical modelling of the peak force generating capacities based on computed tomography scans of the head and neck. RESULTS: Longus capitis and colli are small muscles spanning multiple cervical motion segments. Bilateral peak flexion torque estimates were higher in the upper cervical spine (0.5 Nm), and unlikely to affect motion below the level of C5 (<0.2 Nm). Peak shear estimates were negligible (<20 N), while peak compression estimates were small (<80 N). CONCLUSIONS: These data highlight the complex anatomy and small force capacity of longus capitis and colli, and have implications for their function. In particular, the small peak compression forces indicate that these muscles have a limited capacity to contribute to cervical stability via traditional mechanisms. This implies that the mechanism(s) by which cranio-cervical flexion exercises produce clinical benefits is worth exploring further.

Management of bladder neck stenosis and urethral stricture and stenosis following treatment for prostate cancer.

The aim of this review is to examine all urethral strictures and stenoses subsequent to treatment for prostate cancer, including radical prostatectomy (RP), radiotherapy, high intensity focused ultrasound (HIFU) and cryotherapy. The overall majority respond to endoscopic treatment, including dilatation, direct visual internal urethrotomy (DVIU) or bladder neck incision (BNI). There are adjunct treatments to endoscopic management, including injections of corticosteroids and mitomycin C (MMC) and urethral stents, which remain controversial and are not currently mainstay of treatment. Recalcitrant strictures are most commonly managed with urethroplasty, while recalcitrant stenosis is relatively rare yet almost always associated with bothersome urinary incontinence, requiring bladder neck reconstruction and subsequent artificial urinary sphincter (AUS) implantation, or urinary diversion for the devastated outlet.

The morphology and morphometry of the fovea capitis femoris.

BACKGROUND: There is little published information on the anatomy of the fovea capitis femoris (FCF), the distal attachment site of the ligament of the head of femur (LHF). This study investigates the morphology of the FCF on dry bones in an attempt to answer some of the debate around the functional significance of the LHF. METHODS: The morphological and morphometric details of the FCF were analysed on 125 dry isolated femora (n = 125) from the Anatomy Museum, University of Otago, New Zealand. RESULTS: All femora had a single distinct FCF. The proximal half of the foveal floor was rough indicating the attachment of the LHF, while the distal half or receptacle zone, was smooth. The long axis of most FCF (63.2%) was directed posteroinferiorly. The FCF measured 1.77 ± 0.4 cm (SD) in the longitudinal plane and 1.3 ± 0.32 cm (SD) in the transverse plane and occupied 17% of the surface area of the femoral head. The shape of the FCF was oval in 66%, circular in 28%, and triangular in 6%. In 123 of 125 bones, the FCF was located on the posteroinferior quadrant of the femoral head. Multiple vascular foramina were found in the ligament attachment zone in 76% of the bones and a quarter of the samples showed a shallow perifoveal groove (24%) or a deep perifoveal notch (26%) on the dry bones. DISCUSSION: This study shows that the fovea consistently lies posteroinferior to the true centre of the femoral head and is usually oval in shape. Patent vascular foramina clustered within the LHF attachment site suggest that the ligament conveys some blood supply to the femoral head in adults.

Over-Expression of Activin-ßC Is Associated with Murine and Human Prostate Disease.

Activins are members of the TGF-ß superfamily and have been linked to prostate cancer. There are four mammalian activin subunits (ßA, ßB, ßC, and ßE) that dimerize to form functional proteins. The role of activin-A (ßA-ßA) has been relatively well characterized and has been shown to generally inhibit growth in the prostate. In contrast, little is known about the biological function of the ßC and ßE subunits. Previous work indicated activin-C (ßC-ßC) to be an antagonist of activin-A. This is important because resistance to activin-A growth inhibition occurs during prostate cancer progression. This paradox is not currently well understood. Hence, we hypothesize that local expression of the activin-ßC subunit antagonizes activin-A-dependent growth inhibition and represents a key factor contributing to acquired insensitivity to activin-A observed in prostate cancer progression. To test our hypothesis, we characterized the ventral prostate lobes of 9-month-old transgenic mice over-expressing activin-ßC and examined the expression of activin-ßA, activin-ßC, and the activin intracellular signaling factor, Smad-2, in human prostate diseases. Prostate epithelial cell hyperplasia, low-grade prostatic intraepithelial neoplasia (PIN) lesions, alterations in cell proliferation, and reduced Smad-2 nuclear localization were evident in mice over-expressing activin-ßC. Increased activin-ßA and -ßC subunit immunoreactive scores and decreased Smad-2 nuclear localization were also evident in human prostate cancer. This study suggests that over-expression of activin-ßC is associated with murine and human prostate pathologies. We conclude that the activin-ßC subunit may have therapeutic and/or diagnostic implications in human prostate disease.

Clinical anatomy of the subacromial and related shoulder bursae: A review of the literature.

The subacromial bursa (SAB) is the main bursa of the shoulder. It facilitates normal movement and is also commonly involved in shoulder disorders. Other shoulder bursae have been described but their anatomy has not been well studied. Anatomical variation of shoulder bursae has been suggested and this has implications for clinical practice. This article reviews current knowledge of the normal anatomy of the SAB and related shoulder bursae. A systematic review of the English and German literature was conducted using databases and a hand search of reference lists focusing on the clinical anatomy of the SAB, coracobrachial and subcoracoid bursae and subtendinous bursa of subscapularis. Twenty-four original sources and 13 textbooks were identified. Fifteen studies described the general morphology of the shoulder bursae using cadaveric specimens, eight examined innervation, and one provided information about the blood supply of the SAB. The literature agrees that the SAB is consistent and well innervated with a lateral subdeltoid part and a variable subcoracoid portion. There is variability regarding the consistency, location, and communications of the coracobrachial and subcoracoid bursae and the superior part of the subtendinous bursa of subscapularis, and little information on their nerve and blood supply. Several bursae are present around the shoulder joint. Further research is warranted to understand the precise attachments, dimensions, and communications of the bursae, as well as their nerve and blood supply. This information will improve understanding of the clinical relevance of these bursae and inform appropriate assessment and treatment. Clin. Anat. 30:213-226, 2017. © 2017 Wiley Periodicals, Inc.

The fascicular anatomy and peak force capabilities of the sternocleidomastoid muscle.

PURPOSE: The fascicular morphology of the sternocleidomastoid (SCM) is not well described in modern anatomical texts, and the biomechanical forces it exerts on individual cervical motion segments are not known. The purpose of this study is to investigate the fascicular anatomy and peak force capabilities of the SCM combining traditional dissection and modern imaging. METHODS: This study is comprised of three parts: Dissection, magnetic resonance imaging (MRI) and biomechanical modelling. Dissection was performed on six embalmed cadavers: three males of age 73-74 years and three females of age 63-93 years. The fascicular arrangement and morphologic data were recorded. MRIs were performed on six young, healthy volunteers: three males of age 24-37 and three females of age 26-28. In vivo volumes of the SCM were calculated using the Cavalieri method. Modelling of the SCM was performed on five sets of computed tomography (CT) scans. This mapped the fascicular arrangement of the SCM with relation to the cervical motion segments, and used volume data from the MRIs to calculate realistic peak force capabilities. RESULTS: Dissection showed the SCM has four parts; sterno-mastoid, sterno-occipital, cleido-mastoid and cleido-occipital portions. Force modelling shows that peak torque capacity of the SCM is higher at lower cervical levels, and minimal at higher levels. Peak shear forces are higher in the lower cervical spine, while compression is consistent throughout. CONCLUSIONS: The four-part SCM is capable of producing forces that vary across the cervical motion segments. The implications of these findings are discussed with reference to models of neck muscle function and dysfunction.