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Patterns composed of micron‐sized surface structures can abruptly change the properties of an optical wave front, including its phase, amplitude, polarization, and dispersion. Optical components featuring surface micro‐gratings not only possess optical functionalities that can rival or exceed those of traditional bulky components but can also significantly improve the compactness of optical systems. Herein, the design and fabrication process of As2S3 glass‐based micro‐gratings as well as their resulting optical functionality in the infrared regime are reported. The novel two‐step photochemical process consists of spatially controlled direct laser writing and subsequent selective solution etching. The process yields surface micro‐gratings that possess arbitrarily tunable geometries and design patterns on large‐area flat and curved optical surfaces or substrates, offering a potential new avenue for developing aberration‐corrected infrared‐imaging systems. [ABSTRACT FROM AUTHOR]

Issue linkage is often regarded as a means to enhance international cooperation in the presence of a sovereignty constraint. This constraint means a country can leave an agreement whenever it likes, if the perceived gains from leaving are larger than the gains from staying in the agreement. We set up a model of international agreements in which future gains from cooperation are uncertain, and it is bad realizations that can lead to exit. In this environment, we show that ringfencing dominates issue linkage, even in the absence of complementarities between separate issues, if the degree of uncertainty is sufficiently large. [ABSTRACT FROM AUTHOR]

Acute limb compartment syndrome (ALCS) is a surgical emergency that can have serious consequences unless promptly diagnosed and treated, which is particularly challenging when there is an unusual cause. This is a comprehensive review of reported causes of ALCS. From 1068 included articles, we found 299 discrete causes of ALCS including toxins, infections, endocrine pathology, haematological emergencies, malignancy and iatrogenic ALCS. Familiarity with this wide range of ALCS causes may assist in early diagnosis of this limb‐threatening condition. [ABSTRACT FROM AUTHOR]

Background: This study reports the outcomes of a single institutional experience treating non‐small cell lung cancer (NSCLC) involving the pulmonary hilum with low‐dose stereotactic body radiation therapy (SBRT). The authors also present a series of repeat hilar SBRT. Methods: Inclusion criteria required treatment with SBRT for NSCLC involving regional lymph nodes of the: (i) hilum, (ii) mediastinum, (iii) aortopulmonary window (station 5), or (iv) mainstem bronchus. At least one clinical follow‐up with imaging was required, unless the patient had a prior documented death from cancer. Results: A total of 32 patients with 44 treatments were included, and 37 treatments targeted the hilum directly, with seven concerning the mediastinum, AP window, or mainstem bronchus. Median dose was 28 Gy in four fractions with once‐weekly fractionation. At a median clinical follow‐up of 23 months, local control was 64%. Median overall survival was 24 months, and median progression‐free survival was 15 months. A total of 48% of treatments resulted in complete radiographic response on last imaging follow‐up, and no cases of grade ≥ 3 toxicity were reported. For repeat SBRT (after prior hilar SBRT), local control was 92%. Median overall survival was 20 months, and median progression‐free survival was 19 months. Complete radiographic response was noted after 58% of treatments, with 0 instances of progressive response and no reported side effects. Conclusions: Low‐dose hilar SBRT was efficacious and well‐tolerated, with impressive overall survival and no grade ≥ 3 toxicity. Repeat treatments with SBRT were feasible and effective, demonstrating overall survival, local control, and toxicity comparable to primary treatments. Key points: Significant findings of the study: Low‐dose hilar SBRT was efficacious and well‐toleratedRepeated treatments with SBRT demonstrated encouraging results, comparable to primary treatments What this study adds: This study contributes to the small body of literature concerning hilar SBRTRepeat hilar SBRT was safe and feasibleToxicity was minimal with low‐dose SBRTOnce‐weekly fractionation may have contributed to low rate of side effects. [ABSTRACT FROM AUTHOR]

Background: Surgical fixation of comminuted mid‐shaft clavicle fractures commonly employs intramedullary devices; however, pins with smooth surfaces are prone to migration, whilst threaded pins can be challenging to remove post‐operatively. The aim of this study was to evaluate the biomechanical performance of fractured clavicles repaired using a novel intramedullary Echidna pin device and a non‐threaded Knowles pin. The Echidna pin features retractable spines that engage with the bone to minimize migration and facilitate ease of device removal. Methods: A total of 28 cadaveric clavicle specimens were harvested and a mid‐shaft wedge‐shaped osteotomy was performed to simulate a comminuted butterfly fragment. Specimens were allocated randomly to either the Echidna pin or Knowles pin fracture repair groups. Following surgery, eight specimens in each group underwent 200 cycles of four‐point bending, whilst six specimens in each group underwent torsional testing and pull‐out. Cyclic construct bending stiffness, torsional stiffness and ultimate strength were recorded. Results: Echidna pin intramedullary repair constructs showed significantly greater bending stiffness (mean difference 0.55 N.m/°, 95% confidence interval −0.96, −0.14, P = 0.01) and pull‐out strength (mean difference 146.03 N, 95% confidence interval 29.14, 262.92, P = 0.019) in comparison to Knowles pin constructs. There was no significant difference in torsional stiffness between Echidna pin and Knowles pin repair constructs (P > 0.05). Conclusion: The intramedullary Echidna pin device, which exhibits greater bending strength and pull‐out strength than that of the Knowles pin, may produce a more stable clavicle fracture reduction compared to that of commercially available threadless intramedullary pins. [ABSTRACT FROM AUTHOR]

Changes in joint architecture and muscle loading resulting from total shoulder arthroplasty (TSA) and reverse total shoulder arthroplasty (RSA) are known to influence joint stability and prosthesis survivorship. This study aimed to measure changes in muscle moment arms, muscle lines of action, as well as muscle and joint loading following TSA and RSA using a metal‐backed uncemented modular shoulder prosthesis. Eight cadaveric upper extremities were assessed using a customized testing rig. Abduction, flexion, and axial rotation muscle moment arms were quantified using the tendon‐excursion method, and muscle line‐of‐force directions evaluated radiographically pre‐operatively, and after TSA and revision RSA. Specimen‐specific musculoskeletal models were used to estimate muscle and joint loading pre‐ and post‐operatively. TSA lateralized the glenohumeral joint center by 4.3 ± 3.2 mm, resulting in small but significant increases in middle deltoid force (2.0%BW) and joint compression during flexion (2.1%BW) (p < 0.05). Revision RSA significantly increased the moment arms of the major abductors, flexors, adductors, and extensors, and reduced their peak forces (p < 0.05). The superior inclination of the deltoid significantly increased while the inferior inclination of the rotator cuff muscles decreased (p < 0.05). TSA using an uncemented metal‐backed modular shoulder prosthesis effectively restores native joint function; however, lateralization of the glenoid component should be minimized intra‐operatively to mitigate increased glenohumeral joint loading and polyethylene liner contact stresses. Revision RSA reduces muscle forces required during shoulder function but produces greater superior joint shear force and less joint compression. The findings may help to guide component selection and placement to mitigate joint instability after arthroplasty. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1988–2003, 2019 [ABSTRACT FROM AUTHOR]

Vertical integration in providing financial products and advice is not uncommon. We conduct an experiment in which a financial advisor recommends to a client one of two potential assets to purchase and an asset purchase price. In one setting, the players' incentives are aligned. In another, a conflict of interest exists with the advisor's remuneration favouring one particular asset. We find that conflict influences the advisor's asset recommendation away from the asset that would better serve the client. Disclosure of that conflict, however, influences neither the advisor's asset recommendation nor, more surprisingly, the client's likelihood of rejecting that recommendation. [ABSTRACT FROM AUTHOR]

We construct a modified Hotelling‐type model of two media providers, each of whom can issue fake and/or real news and each of whom can invest in the debunking of their rival's fake news. The model assumes that consumers have an innate preference for one provider or the other and value real news. However, that valuation varies according to their bias favouring one provider or the other. We demonstrate a unique subgame perfect Nash equilibrium in which only one firm issues fake news and we show, in this setting, that increased polarisation of consumers (represented by a wider distribution) increases the prevalence of both fake news and debunking expenditures and is welfare‐reducing. We also show, inter alia, that a stronger preference by consumers for their preferred provider lowers both fake news and debunking. Finally, we compare monopoly and duopoly market structures in terms of 'fake news' provision and show that a public news provider can be welfare‐improving. [ABSTRACT FROM AUTHOR]

Rotator cuff tears are known to affect clinical outcome of reverse total shoulder arthroplasty (RSA). This study aimed to use computational modelling to quantify the effect of rotator cuff tear severity on muscle and joint forces after RSA, as well as stresses at the glenosphere, base‐plate, fixation screws, scapula, and humeral components. A multi‐body musculoskeletal model of the glenohumeral joint was developed comprising the scapula, humerus and nine major upper limb muscles. Simulations of abduction and flexion after RSA were performed in the case of the intact rotator cuff and tears to (i) supraspinatus; (ii) supraspinatus and infraspinatus, and (iii) supraspinatus, infraspinatus and subscapularis. The intact and supraspinatus deficient rotator cuff resulted in the largest calculated muscle forces, glenohumeral joint contact forces and implant stresses. Peak glenohumeral joint forces during flexion were lower than those during abduction in all cases; however, substantially more posterior joint shear force was generated during flexion than abduction. A tear involving the supraspinatus and infraspinatus reduced glenohumeral joint forces by a factor of 8.7 during abduction (603.1 N) and 7.1 during flexion (520.7 N) compared to those in the supraspinatus deficient shoulder. RSA with an intact or supraspinatus deficient rotator cuff produces large glenohumeral joint forces that may increase base‐plate failure risk, particularly during flexion when posterior shear forces are largest. Infraspinatus tears after RSA greatly reduce glenohumeral joint compression and may ultimately reduce joint stability. Future research ought to focus on experimental validation of subject‐specific muscle recruitment strategies and joint loading after RSA. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res [ABSTRACT FROM AUTHOR]

This Video S1 will be an integral part of training the theatre staff and surgeons as a standard operating policy for safe placement of the rectus sheath catheter and its use. Standardising rectus sheath catheter placement for midline laparotomy -a video vignette I Dear Editor i , The use of rectus sheath catheter is an effective alternative to neuraxial anaesthesia in midline laparotomy procedures. [Extracted from the article]

Background Double-row rotator cuff tendon repair techniques may provide superior contact area and strength compared with single-row repairs, but are associated with higher material expenses and prolonged operating time. The purpose of this study was to evaluate gap formation, ultimate tensile strength and stiffness of a single-row cruciate suture rotator cuff repair construct, and to compare these results with those of the Mason-Allen and SutureBridge repair constructs. Methods Infraspinatus tendons from 24 spring lamb shoulders were harvested and allocated to cruciate suture, Mason-Allen and SutureBridge repair groups. Specimens were loaded cyclically between 10 and 62 N for 200 cycles, and gap formation simultaneously measured using a high-speed digital camera. Specimens were then loaded in uniaxial tension to failure, and construct stiffness and repair strength were evaluated. Results Gap formation in the cruciate suture repair was significantly lower than that of the Mason-Allen repair (mean difference = 0.6 mm, P = 0.009) and no different from that of the SutureBridge repair ( P > 0.05). Both the cruciate suture repair (mean difference = 15.7 N/mm, P = 0.002) and SutureBridge repair (mean difference = 15.8 N/mm, P = 0.034) were significantly stiffer than that of the Mason-Allen repair; however, no significant differences in ultimate tensile strength between repair groups were discerned ( P > 0.05). Conclusion The cruciate suture repair construct, which may represent a simple and cost-effective alternative to double-row and double-row equivalent rotator cuff repairs, has comparable biomechanical strength and integrity with that of the SutureBridge repair, and may result in improved construct longevity and tendon healing compared with the Mason-Allen repair. [ABSTRACT FROM AUTHOR]

Background Little is known about the prevalence of proximal humeral non-union. There is disagreement on what constitutes union, delayed union and non-union. Our aim was to determine the prevalence of these complications in proximal humeral fractures ( PHFs) admitted to trauma hospitals. Methods The Victorian Orthopaedic Trauma Outcomes Registry identified 419 cases of PHFs, of which 306 were analysed. Three upper limb orthopaedic surgeons used X-rays to classify fractures according to the Neer classification and determine union. Twelve-item Short Form Health Survey scores were used to assess patient health and wellbeing. Results Of 306 cases, 49.4% reached union. Median time to union was 100 days (confidence interval 90-121). Of these, 17.0% united by 60 days, 8.5% united by 89 days and 23.9% united after 90 days, demonstrating 'prolonged delayed union'. There were 25 non-unions with a prevalence of 8.2%, most occurring in two-part surgical neck fractures. Conclusion Our cohort of largely displaced PHFs admitted to trauma hospitals had a non-union prevalence of 8.2% and an overall delayed union prevalence of 32.4%. Consensus is required on definitions of non-union and delayed union timeframes. [ABSTRACT FROM AUTHOR]

This paper considers governmental incentives to provide information to local consumers about the relative merits of local versus foreign goods. We construct a model in which a local firm in a small, open economy competes in its domestic market with imports. Consumers are willing to pay an idiosyncratic premium for the local product, drawn from some support that the importing country government can affect through a costly information campaign. We examine incentives to undertake such a campaign in autarky and in the case of trade. We show, inter alia, that while a national welfare-maximising government will always wish to shift this distribution upwards, it may not wish to reduce the variance of valuations, and that the optimal response of a foreign government will be to increase any support it offers to its exporters. Furthermore, falling world prices generally reduce the attractiveness of such a campaign both to a welfare-maximising government and to one that cares only for domestic profits. [ABSTRACT FROM AUTHOR]

Context Good preparation for surgical procedures has been linked to better performance and enhanced learning in the operating theatre. Mental imagery is increasingly used to enhance performance in competitive sport and there has been recent interest in applying this in surgery. Objectives This study aims to identify the mental imagery components of preoperative preparation in orthopaedic trauma surgery and to locate these practices in existing socio-material theory in order to produce a model useful for surgical skills training. Methods Semi-structured interviews were conducted with nine orthopaedic surgeons. Participants were identified by personal recommendation as regularly performing complex trauma operations to a high standard, and by affiliation to an international instruction course in trauma surgery. Interviews were audio-recorded and transcripts were independently analysed using thematic analysis. Results Analysis revealed that surgeons interact intensively with multiple colleagues and materials during their preparatory activities. Such interactions stimulate mental imagery in order to build strategy and rehearse procedures, which, in turn, stimulate preparatory interactions. Participants identified the discussion of a preoperative 'plan' as a key engagement tool for training junior surgeons and as a form of currency by which a trainee may increase his or her participation in a procedure. Conclusions Preoperative preparation can be thought of as a socio-material ontology requiring a surgeon to negotiate imaginal, verbal and physical interactions with people, materials and his or her own mental imagery. Actor-network theory is useful for making sense of these interactions and for allowing surgeons to interrogate their own preparative processes. We recommend supervisors to use a form of preoperative plan as a teaching tool and to encourage trainees to develop their own preparatory skills. The ability of a trainee to demonstrate sound preparation is an indicator of readiness to perform a procedure. [ABSTRACT FROM AUTHOR]

This paper constructs a model of the recorded music market to investigate the consequences of local content requirements in broadcasting for the 'internationalization' of domestic music. It models the entry decisions of bands, the contracting decisions of record companies, the airplay decisions of radio stations and the radio listening and recording purchasing decisions of consumers. The paper shows that a local content quota leads, perversely, to the increased internationalization of domestic music. A quota that also requires increased broadcasting of 'new' music yields an additional welfare loss but does nothing to a record company's incentives to sign up new bands. [ABSTRACT FROM AUTHOR]

This paper analyses a setting in which a vertically integrated fair-trade firm competes against vertically disintegrated, profit-maximising oligopolists. Consumers of the fair-trade product derive a 'warm glow' that depends on the wage paid to fair-trade producers; the firm returns all surplus to its farmers. Trade integration will unambiguously increase the size of the fair-trade firm, but the relative size compared to oligopolists may shrink. Furthermore, we show that the 'warm glow' effect may support a marginal expansion of the volume of fair trade, but for rather perverse reasons. [ABSTRACT FROM AUTHOR]

Background Bisphosphonates ( BPs) are widely used for the treatment of osteoporosis. Oversuppression of bone turnover with BPs may paradoxically limit the reserve capacity of bone to heal. The aim of this review was to study the predisposition of some patients to delayed/non-union of upper limb fractures associated with BPs and give recommendations on how they should be treated. Methods A systematic search of two electronic databases was conducted to identify relevant studies for inclusion. All relevant studies found were included and assessed through methodology criteria predetermined by two independent reviewers. Results Six papers comprising of three case reports, one nested case control study, one restrospective review and one randomized clinical trial were used. In comparative studies of pre-fracture BP use, a 6-day delay in average healing times was reported among BP users. There was no elevation in risk of non-union. Post-fracture BP use was associated with an approximate doubling of the risk of non-union. Timing of BP therapy initiation following a fracture was not associated with a difference in healing times. An atypical ulna fracture treated conservatively resulted in non-union, there was no effect of type of surgical treatment on distal radius fracture healing and there was insufficient evidence to comment on humeral fracture treatment. Conclusions Differences in union time between BP users and non-users are not significant enough to change current practice patterns and do not outweigh the benefits of BP therapy. There is no evidence to encourage early surgical management of BP-related upper limb fractures. [ABSTRACT FROM AUTHOR]

Background Confirming the presence of arteries crossing the osteotendinous junctions ( OTJs) of the rotator cuff may explain why rates of avascular necrosis ( AVN) of the humeral head vary between three- and four-part proximal humeral fractures. It is hypothesized that the humeral head remains better vascularized in three-part fractures because one tuberosity with its inserting rotator cuff tendons is still attached to the articular fragment and supplying it with blood. Methods Eighty rotator cuff tendons from 20 shoulder girdles of cadavers aged 68-94 years were studied. In six shoulder girdles, the anterior circumflex humeral artery and posterior circumflex humeral artery ( PCHA) were injected with ink, and the extra- and intraosseous courses of the vasculature were dissected until the OTJs of the rotator cuff. Results The rotator cuff insertions received an arterial supply across their OTJs in 50% of cases (75% in supraspinatus, 67% in subscapularis, 33% in infraspinatus and 20% in teres minor). Supraspinatus and subscapularis insertions were vascularized by the arcuate artery, while the insertions of infraspinatus and teres minor were supplied by an unnamed terminal branch of the PCHA. This was named 'posterolateral artery'. Conclusion The presence of arteries crossing the OTJs of the rotator cuff, as well as the differences in the frequency arteries crossed the OTJs of individual rotator cuff tendons, may help explain why there is a lower rate of AVN of the humeral head in thee-part, compared with four-part proximal humeral fractures. [ABSTRACT FROM AUTHOR]

Background The study of intraosseous vasculature has always been challenging due to the hard, calcified structure of bone. Techniques used to study intraosseous vasculature usually involve diaphanization with a Spalteholz technique, followed by X-ray imaging to display the radio contrast-injected blood vessels. These techniques produce results with fine detail when successfully executed. However, high failure rates and the extensive length of time required to perform these techniques are drawbacks. This paper describes a faster, alternative method for the study of intraosseous vasculature. Method Five embalmed and two fresh shoulder girdles were harvested from six cadavers. Cannulas were inserted into the origins of the anterior ( ACHA) and posterior ( PCHA) circumflex humeral arteries and injected with ink diluted in water or 6% hydrogen peroxide. The arteries and their branches were dissected until they entered their respective bony foraminae. A hammer, chisel, bone nibbler and mounted needles were used to follow the intraosseous course of these arteries and their branches. Results The intraosseous vasculature was seen in all specimens. The branches of the main nutrient artery to the proximal humerus were followed until they reached articular cartilage or crossed cortical bone again to enter the rotator cuff tendons. Discussion An innovative, new approach to the study of intraosseous vasculature with direct visualization of the intraosseous arteries of the proximal humerus is described. [ABSTRACT FROM AUTHOR]

Bulk glasses having the compositions As42 S58, As36 Sb6 S58, and As36 Ge6 S58 have been irradiated at 800 nm using a femtosecond-pulsed laser to determine the relationship between composition and photo-response. Localized variation in the glass volume (photo-expansion) has been determined through interferometric measurements of surface exposures, whereas induced refractive index change (photo-darkening) was determined from the diffraction efficiency of subsurface direct-written phase gratings. To understand the compositional dependence of the photo-response, the linear and nonlinear optical properties and structure of the unexposed glasses have been compared. The ablation threshold is shown to be controlled by variation of the nonlinear absorption, related to shifts of the absorption band gap with exchange of As by Ge or Sb. Changes in the unexposed network structure show that partial replacement of As by Ge or Sb induces an increased number of As-As bonding defects in the glass, particularly in the form of As4 S4 molecular units which become polymerized into the network, impacting the photo-modification process. The Ge was found to induce an increase in the ablation threshold, and enhance both photo-darkening and photo-expansion effects, whereas Sb was shown to decrease ablation threshold and inhibit photo-darkening while enhancing photo-expansion. [ABSTRACT FROM AUTHOR]

The purposes of this study were to determine the contributions of each shoulder muscle to glenohumeral joint force during abduction and flexion in both the anatomical and post-operative shoulder and to identify factors that may contribute to the incidence of glenoid component loosening/failure and joint instability in the shoulder after reverse shoulder arthroplasty (RSA). Eight cadaveric upper extremities were mounted onto a testing apparatus. Muscle lines of action were measured, and muscle forces and muscle contributions to glenohumeral joint forces were determined during abduction and flexion of the pre-operative anatomical shoulder and of the shoulder after arthroplasty. Muscle forces in the middle deltoid during abduction and those in the middle and anterior deltoid during flexion were significantly lower in the reverse shoulder than the pre-operative shoulder ( p < 0.017). The resultant glenohumeral joint force in the reverse shoulder was significantly lower than that in the pre-operative shoulder; however, the superior shear force acting at the glenohumeral joint was significantly higher ( p < 0.001). Reverse total shoulder arthroplasty reduces muscle effort in performing lifting and pushing tasks; however, reduced joint compressive force has the potential to compromise joint stability, while an increased superior joint shear force may contribute to component loosening/failure. Because greater superior shear force is generated in flexion than in abduction, care should be taken to avoid excessive shoulder loading in this plane of elevation. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29:1850-1858, 2011 [ABSTRACT FROM AUTHOR]

Clinical practice guidelines for haemodynamically unstable patients with pelvic fractures were initiated in February 2005 at our level 1 trauma centre. The purpose of the present study was to evaluate guideline adherence and outcome of guideline performance. In a retrospective clinical study all patients admitted with a pelvic fracture from August 2003 to March 2007 were identified from a prospective trauma registry database. Medical records of all patients were reviewed. Patients with pelvic fractures associated with haemodynamic instability were included. Patients were divided into two groups: preguideline and postguideline. The two groups were compared. Main outcome measurements were 24 h fluid requirement, total blood transfusion, length of stay in ICU and hospital, and mortality rate. Of the 210 patients with pelvic fractures, 32 patients met the inclusion criteria. Preguideline group consisted of 13 and postguideline group 19 patients. Non-invasive pelvic stabilization was applied significantly more postguideline (92.3% vs 33.3%, P= 0.004). Focused abdominal sonography for trauma and pelvic angiography/embolization have been used significantly more in the postguideline group (5 vs 14, P= 0.046 and 0 vs 6, P= 0.025, respectively). There was no significant difference in 24 h fluid requirement, total blood transfusion, length of stay in ICU and hospital, and mortality rate between the two groups. The introduction of guidelines has influenced the approach to haemodynamically unstable patients with pelvic fractures. Multiple factors can potentially influence the strict adherence to the guideline. Care provided can still be improved by addressing the challenges in guideline performance. [ABSTRACT FROM AUTHOR]

We consider private and public incentives for domestic firms to merge in the face of foreign entry. We consider the gains to two merging firms and to national welfare in a linear Cournot model. With heterogeneous firms and possible synergies, greater foreign entry tends to enhance both private and public incentives for domestic mergers. Thus, policymakers have no cause to doubt the intentions of firms seeking to merge: when it is in the firms' interests then it is also in the public interest. However, at least for certain parameterisations, private gains from mergers become positive at a lower level of foreign entry than do public gains. This suggests that private firms may have an incentive to overstate the degree of foreign competition they anticipate facing—for example, after liberalizing foreign investment rules—to persuade policymakers that a proposed domestic merger is in the national interest. [ABSTRACT FROM AUTHOR]

Background: Acute compartment syndrome is a serious and not uncommon complication of limb trauma. The condition is a surgical emergency, and is associated with significant morbidity if not managed appropriately. There is variation in management of acute limb compartment syndrome in Australia. Methods: Clinical practice guidelines for the management of acute limb compartment syndrome following trauma were developed in accordance with Australian National Health and Medical Research Council recommendations. The guidelines were based on critically appraised literature evidence and the consensus opinion of a multidisciplinary team involved in trauma management who met in a nominal panel process. Results: Recommendations were developed for key decision nodes in the patient care pathway, including methods of diagnosis in alert and unconscious patients, appropriate assessment of compartment pressure, timing and technique of fasciotomy, fasciotomy wound management, and prevention of compartment syndrome in patients with limb injuries. The recommendations were largely consensus based in the absence of well-designed clinical trial evidence. Conclusions: Clinical practice guidelines for the management of acute limb compartment syndrome following trauma have been developed that will support consistency in management and optimize patient health outcomes. [ABSTRACT FROM AUTHOR]

The objective of the present study was to determine the instantaneous moment arms of 18 major muscle sub-regions crossing the glenohumeral joint during coronal-plane abduction and sagittal-plane flexion. Muscle moment-arm data for sub-regions of the shoulder musculature during humeral elevation are currently not available. The tendon-excursion method was used to measure instantaneous muscle moment arms in eight entire upper-extremity cadaver specimens. Significant differences in moment arms were reported across sub-regions of the deltoid, pectoralis major, latissimus dorsi, subscapularis, infraspinatus and supraspinatus ( P < 0.01). The most effective abductors were the middle and anterior deltoid, whereas the most effective adductors were the teres major, middle and inferior latissimus dorsi (lumbar vertebrae and iliac crest fibers, respectively), and middle and inferior pectoralis major (sternal and lower-costal fibers, respectively). In flexion, the superior pectoralis major (clavicular fibers), anterior and posterior supraspinatus, and anterior deltoid were the most effective flexors, whereas the teres major and posterior deltoid had the largest extensor moment arms. Division of multi-pennate shoulder muscles of broad origins into sub-regions highlighted distinct functional differences across those sub-regions. Most significantly, we found that the superior sub-region of the pectoralis major had the capacity to exert substantial torque in flexion, whereas the middle and inferior sub-regions tended to behave as a stabilizer and extensor, respectively. Knowledge of moment arm differences between muscle sub-regions may assist in identifying the functional effects of muscle sub-region tears, assist surgeons in planning tendon reconstructive surgery, and aid in the development and validation of biomechanical computer models used in implant design. [ABSTRACT FROM AUTHOR]

Background: Acute compartment syndrome is a serious and not uncommon complication of limb trauma. The condition is a surgical emergency and is associated with significant morbidity if not diagnosed promptly and treated effectively. Despite the urgency of effective management to minimize the risk of adverse outcomes, there is currently little consensus in the published reports as to what constitutes best practice in the management of acute limb compartment syndrome. Methods: A structured survey was sent to all currently practising orthopaedic surgeons and accredited orthopaedic registrars in Australia to assess their current practice in the management of acute, traumatic compartment syndrome of the leg. Questions were related to key decision nodes in the management process, as identified in a literature review. These included identification of patients at high risk, diagnosis of the condition in alert and unconscious patients, optimal timeframe and technique for carrying out a fasciotomy and management of fasciotomy wounds. Results: A total of 264 valid responses were received, a response rate of 29% of all eligible respondents. The results indicated considerable variation in management of acute compartment syndrome of the leg, in particular in the utilization of compartment pressure measurement and the appropriate pressure threshold for fasciotomy. Of the 78% of respondents who regularly measured compartment pressure, 33% used an absolute pressure threshold, 28% used a differential pressure threshold and 39% took both into consideration. Conclusions: There is variation in the management of acute, traumatic compartment syndrome of the leg in Australia. The development of evidence-based clinical practice guidelines may be beneficial. [ABSTRACT FROM AUTHOR]

Background: Although orthopaedic trauma results in significant disability and substantial financial cost, there is a paucity of large cohort studies that collectively describe the functional outcomes of a variety of these injuries. The current study aimed to investigate the outcomes of patients admitted with a range of orthopaedic injuries to adult Level 1 trauma centres. Methods: Patients were recruited from the Victorian Orthopaedic Trauma Outcomes Registry (VOTOR), which included all patients with orthopaedic trauma admitted to the two adult Level 1 trauma centres in Victoria (Australia). Patients were categorised into three groups; isolated orthopaedic injuries, multiple orthopaedic injuries and orthopaedic and other injuries. Demographic and injury data were collected from the medical record and hospital/trauma databases, and functional outcome instruments were given at 6 months post-injury. Results: Of the 1303 patients recruited for VOTOR over a 12-month period, 1181 patients were eligible for the study and a response rate of 75.6% was obtained at 6 months post-injury. Patients reported ongoing pain (moderate-severe: 37.2%), disability (79.5%) and inability to return to work (35.2%). Poorer outcomes were evident in patients with orthopaedic and other injuries than those with single or multiple orthopaedic injuries alone. Conclusion: A large percentage of patients have ongoing pain and disability and a reduced capacity to return to work 6 months after orthopaedic trauma. Further research into the long-term outcomes of patients with orthopaedic injuries is required to identify patient subgroups and specific injuries and procedures that result in high morbidity. [ABSTRACT FROM AUTHOR]

This paper studies the interaction between negative gearing and three capital gains tax regimes – the current Australian system, the one that prevailed between 1985 and 1999 and a realisation tax that mimics an accruals tax. We report estimates of the effective rates of income tax for each regime in two scenarios – slow anticipated real capital gains and very rapid unanticipated real capital gains. We conclude that negative gearing should be retained and capital gains taxation reformed to approximate an accruals tax. This desirable package would be no harder to administer than the current regime. [ABSTRACT FROM AUTHOR]

The paper develops a model in which foreign and domestic manufacturers producing differentiated goods sell through spatially differentiated retailers. There is free entry into retailing but access to the retail distribution network (by manufacturers) may be controlled. The author considers a domestic vertical control mechanism in which domestic retailers carry only domestic brands (termed“domestic dealing”) and compares the use of tariffs on imports and the enforcement of domestic dealing restrictions as means of increasing domestic welfare. It is shown that domestic dealing will always be prohibited when tariffs can be used. When trade policy is not available, however, domestic dealing may be desirable. [ABSTRACT FROM AUTHOR]

Motivated by the observation that many countries with an active industrial policy also have a lax competition policy, this paper argues that restricting firm numbers may be a means of rendering industrial policy more effective. A simple model is set up in which a subsidy is desirable to correct a general externality but may induce over-entry. Restricting the number of firms then renders the subsidy policy more effective in correcting the externality problem. [ABSTRACT FROM AUTHOR]

Looks at New Zealand's trade policy, while examining the World Trade Organization Trade Policy Review of New Zealand (TPRNZ) in 1996. Details on trade reform in New Zealand; Information on New Zealand's economic environment; Reference to New Zealand's trading strategies; Measures which affect New Zealand's import and export trading.

Stresses two aspects of European trade and trade policy. Cliche on the European community; Motivating factor for non-European countries to form preferential trading blocs; Analytic expressions for optimal tariffs; Political motivation for tariffs.

Examines the effects of an incremental export subsidy in a partial equilibrium framework in Australia. Presentation of a partial equilibrium framework for solving inter-temporal optimization problem; Use of storage costs or discounting in solving a unique optimum time path; Requirements in developing export markets.

Shows that non-discriminatory domestic taxes and subsidies are imperfect substitutes for trade policy in a customs union in Canada. Specification of trading patterns; Illustration of the restrictive condition under which a union will form.

The article presents the observations of a participant in the planning of the Milton Keynes city project in Great Britain in 1973 from the point of view of an architect. Some of the characteristics of a housing project, based on the 25 year experiment of the Milton Keynes project, include: a good fit between what was provided and what was desired; the power of good design in which the layout as a whole is more than the sum of its parts; and layering.

This article comments on initiatives and debates around authors depositing post-prints of their articles in institutional repositories. Post-prints are not the final article. A widely held definition of a post-print is the final draft of an author's manuscript, as accepted for publication, incorporating referees' suggestions, but before it has undergone the copyediting and proof-correction process. A reader is faced with two copies of the same article at different stages of the publication process. If the author has previously deposited a pre-print on a pre-print server, or on their own personal or institution's Web site, then there is a third version. Citation analysis is also used to assess the quality of an individual author's work, both by their peers, their employers and by grant-awarding authorities. If the trends of self-archiving of postprints continue, it would potentially threaten the revenue streams that underwrite the processes of publication. If, as a result of the widespread use of post-print archives, journals begin to see the sort of declines in paid subscriptions that those offering free online archives are experiencing, this could result in further price escalation that will restrict availability rather than enhance it.

The article offers information underutilized capacity of the private sector surgical training for educating our future surgical workforce. Topics discussed include ways in which performing an appendicectomy requires much more than technical expertise; emergency procedures such as appendicectomy are performed in the public sector; and need of surgical educator.

Background The classification of proximal humeral fractures remains challenging. The two main classification systems used, the Neer and the AO classification, have both been shown to have less than ideal interobserver agreement. Agreement in classification is required, however, to guide fracture management. Method Data from the Victorian Orthopaedic Trauma Outcomes Registry were collected and the X-rays of 104 proximal humeral fractures were reviewed by three orthopaedic consultants. They classified the fractures according to the Neer and AO classifications, as well as their simplified versions. Interobserver agreement was then assessed using kappa statistics. Results Interobserver agreement was better overall in the Neer classification, which was moderate (kappa = 0.40-0.58), than the AO classification, which was fair to moderate (kappa = 0.31-0.54). When simplified, the Neer and AO classification interobserver agreement remained similar. Conclusion The classification of proximal humeral fractures with both the Neer and the AO systems remains difficult with minimal improvements seen when reducing the number of categories in each classification system. From these results, the Neer classification system would appear slightly more useful in clinical practice to guide treatment. [ABSTRACT FROM AUTHOR]