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Objective: To determine the incidence of patients presenting in pain to a large Australian inner-city emergency department (ED) using a clinical text deep learning algorithm., Materials and Methods: A fine-tuned, domain-specific, transformer-based clinical text deep learning model was used to interpret free-text nursing assessments in the electronic medical records of 235,789 adult presentations to the ED over a three-year period. The model classified presentations according to whether the patient had pain on arrival at the ED. Interrupted time series analysis was used to determine the incidence of pain in patients on arrival over time. We described the changes in the population characteristics and incidence of patients with pain on arrival occurring with the start of the Covid-19 pandemic., Results: 55.16% (95%CI 54.95%-55.36%) of all patients presenting to this ED had pain on arrival. There were differences in demographics and arrival and departure patterns between patients with and without pain. The Covid-19 pandemic initially precipitated a decrease followed by a sharp, sustained rise in pain on arrival, with concurrent changes to the population arriving in pain and their treatment., Discussion: Applying a clinical text deep learning model has successfully identified the incidence of pain on arrival. It represents an automated, reproducible mechanism to identify pain from routinely collected medical records. The description of this population and their treatment forms the basis of intervention to improve care for patients with pain. The combination of the clinical text deep learning models and interrupted time series analysis has reported on the effects of the Covid-19 pandemic on pain care in the ED, outlining a methodology to assess the impact of significant events or interventions on pain care in the ED., Conclusion: Applying a novel deep learning approach to identifying pain guides methodological approaches to evaluating pain care interventions in the ED, giving previously unavailable population-level insights., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: In general, the quality of pain care in emergency departments (ED) is poor, despite up to 80% of all ED patients presenting with pain. This may be due to the lack of well-validated patient-reported outcome measures (PROMs) of pain care in the ED setting. The American Pain Society-Patient Outcome Questionnaire-Revised Edition (APS-POQ-R), with slight modification for ED patients, is a potentially useful PROM for the adult ED, however it is yet to be completely validated., Methods: Adult patients, who had presented with moderate to severe acute pain, were recruited at two large inner-city EDs in Australia. A modified version of the APS-POQ-R was administered at the completion of their ED care. Responses were randomly split into three groups and underwent multiple rounds of exploratory and confirmatory factor analysis with testing for construct, convergent, divergent validity and internal consistency., Results: A total of 646 ED patients (55.6% female), with a median age of 48.3 years, and moderate to severe pain on arrival, completed the ED-modified APS-POQ-R. Psychometric evaluation resulted in a reduced nine-question tool, which measures three constructs (pain relief and satisfaction (α=0.891), affective distress (α=0.823) and pain interference (α=0.908)) and demonstrated construct, convergent, divergent validity, and internal consistency., Conclusions: This new tool, which we refer to as the American Pain Society-Patient Outcome Questionnaire-Revised for the ED (APS-POQ-RED), should form the basis for reporting patient-reported outcomes of ED pain care in future quality improvement and research., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

The success of deep learning in natural language processing relies on ample labelled training data. However, models in the health domain often face data inadequacy due to the high cost and difficulty of acquiring training data. Developing such models thus requires robustness and performance on new data. A generalised incremental multiphase framework is proposed for developing robust and performant clinical text deep learning classifiers. It incorporates incremental multiphases for training data size assessments, cross-validation setup to avoid test data bias, and robustness testing through inter/intra-model significance analysis. The framework's effectiveness and generalisation were confirmed by the task of identifying patients presenting in 'pain' to the emergency department.

Introduction and Designs: Take-home naloxone (THN) interventions are an effective response to preventing overdose deaths, however uptake across Australia remains limited. This project designed, implemented and evaluated a model of care targeting opioid users attending alcohol and other drug (AOD) treatment, needle and syringe programs (NSP) and related health services targeting people who inject drugs., Design and Methods: Service providers, consumers and regulators collaboratively designed a THN brief intervention (ORTHN, Overdose Response with Take-Home Naloxone) involving client education and supply of naloxone in pre-filled syringes, delivered by nursing, allied health and NSP workers. ORTHN interventions were implemented in over 15 services across New South Wales, Australia. The evaluation included client knowledge, attitudes, substance use and overdose experiences immediately before and 3 months after ORTHN intervention in a subsample of participants., Results: Six hundred and sixteen interventions were delivered, with 145 participants recruited to the research subsample, of whom 95 completed the three-month follow up. Overdose-related attitudes amongst participants improved following ORTHN, with no evidence of increased substance use or failure to implement other 'first responses' (e.g. calling an ambulance). Nine participants (10%) reversed an overdose using THN in the follow-up period. Participants identified a willingness to access THN from a range of services. While a minority (16%) indicated they were unwilling to pay for THN, the median price that participants were willing to pay was $AUD20 (IQR $10.40)., Discussion and Conclusions: The ORTHN model of care for THN appears an effective way to disseminate THN to people who use opioids attending AOD, NSP and related health-care settings., (© 2019 Australasian Professional Society on Alcohol and other Drugs.)

Objective: To describe characteristics of ED admissions that resulted in unsolicited complaints and compare with overall ED admissions. The site utilised is an inner city tertiary hospital, with 630 beds, with approximately 82 600 annual presentations, where 32.5% were children., Methods: Complaints between the dates of 27 November 2012 and 10 March 2016 were reviewed. Performance indicators and the distribution of presentations by diagnostic code were reviewed., Results: A total of 572 different complaint reasons were found and grouped into 12 categories. The most common reasons for complaints were treatment (33.2%) and communication (28.3%), and most complaints concerned medical staff. Other variables including wait times have no effect on patient complaints. Utilising aggregate numbers, the overall paediatric complaint ratio was 0.98:1000 presentations, and the total adult department complaints were 1.78:1000 presentations., Conclusion: As seen in this study the vast majority of patient complaints were associated with treatment and communication issues and skewed towards doctors. It may be feasible for medical staff to undertake communication training as clinician-patient communication in the ED is an important aspect in the improvement of patient satisfaction and in decreasing patient complaints as waiting times and triage categories had no major influence on patient complaints., (© 2018 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.)

Background: Among people who inject drugs (PWID), the prevalence of hepatitis C virus (HCV) infection is high; however HCV treatment uptake remains low. New models of care are needed to address the growing burden of HCV-related disease in PWID and to understand the barriers to assessment and treatment of HCV. This study evaluated assessment and treatment for HCV infection among PWID attending an opioid substitution treatment (OST) clinic with an integrated peer support worker model., Methods: Clients with a history of IDU and chronic HCV infection, attending the Newcastle Pharmacotherapy Service, Newcastle Australia, were recruited as part of a multisite prospective observational study (the ETHOS Cohort). Additional chart review was conducted for clients not enrolled in the ETHOS Cohort. A peer support worker was introduced to complement and extend services offered by the clinical team. Client contacts and assessments with a nurse and/or peer worker were evaluated, including those who commenced HCV treatment., Results: A total of 1447 clients attended the OST service during February 2009 and June 2014. Of these, 378 (26%) were assessed by a nurse and 242 (17%) by a clinician. HCV treatment was commenced by 20 (5%) participants and 15 (75%) achieved a sustained virological response (SVR). During May 2009 and July 2011, 332 nurse contacts and 726 peer worker contacts were evaluated. The nurse-led contacts were related to HCV treatment (50%) and review of pathology tests (34%), whereas peer worker contacts included discussion about HCV treatment (75%), education, counselling and/or support (53%) and general discussion about HCV infection (59%)., Conclusion: These data demonstrate that peer support workers facilitate broader discussion about HCV treatment, education and/or support, allowing nurses to focus on HCV-related assessment and treatment. HCV treatment uptake was very low in this cohort, but SVR was high. The integration of peer support workers in treatment programs within OST clinics may address barriers to HCV care, but further studies are needed to assess their impact on assessment and treatment outcomes., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Aim: Peer support services have been shown to be beneficial in increasing uptake and adherence to treatment in other areas but few examples of these services exist in hepatitis C (HCV) care. This study examined the performance of two community-controlled peer support services operating within a larger study aimed at increasing access to HCV care and treatment for opiate substitution treatment (OST) clients, ETHOS., Methods: Semi-structured interviews were conducted in two clinics with three groups of participants: clients (n=31), staff (n=8) and peer workers (n=3) and examined the operation of the service in relation to process, outputs and impacts., Results: There was a very strong positive response to the peer worker services reported by staff and clients who had and had not interacted with a peer worker. A number of changes were reported that were not explicit goals of the service including providing access to additional services for clients and staff, peer workers acting as mediators between clients and staff and a less tangible notion of a changing "feel" of the clinic to a more positive and client-friendly social and physical space. Explicit goals of the service were also reported in peer workers supporting clients to consider and prepare for treatment (via blood tests and other assessments) as well as provide information and support about treatment., Conclusions: The peer support service was acceptable to clients and clinic staff. All groups of participants noted that the service met its goals of engaging clients, building trusting relationships and providing instrumental support for clients to access HCV treatment. Peer workers may also contribute to more effective deployment of health resources by preparing clients for clinical engagement with HCV health workers., (Copyright © 2015 Elsevier B.V. All rights reserved.)

BACKGROUND: The purpose of this study was to examine the influence of proximal retrograde intramedullary nail position on proximal femoral strain, since stress risers occurring at the end of an implant can increase fracture risk. METHODS: Proximal femoral strains during axial and torsional loading were measured in composite Sawbone femurs after placement of retrograde intramedullary nails that ended at three different locations (2 cm proximal, 4 cm distal, and at the level of the lesser trochanter). RESULTS: No statistically significant difference was found between the axial or torsional strain observed in the intact femur and that seen after placement of a retrograde femoral nail ending at any of the three positions. Gages proximal to the nail tip demonstrated higher strains than the strains for the intact femur when compared with gages distal to the nail tip. CONCLUSION: The ending location of a retrograde nail in the proximal femur does not appear to significantly alter strain in the proximal femur under the axial and torsional loading methods used in the study.

The compliance technique has been used to monitor crack length during fracture and fatigue testing of materials. Difficulties arise when this technique is applied to anisotropic biological materials such as bone. In this tutorial, two different methods of analyzing compliance calibration data are described: the standard ASTM method and a new approach developed by the authors specifically for anisotropic materials. An example is given showing how data from equine cortical bone can be analyzed. In this example, calibration tests were conducted on thirty-six three point bend specimens machined from the mid-diaphysis of six pairs of equine third metacarpal bones. Cracks were propagated in three orientations with respect to the long axis of the bone: transverse, longitudinal, and radial. Specimen compliance was determined for a crack range of 0.30 to 0.65 times the specimen width from load vs. crack opening displacement data. The results demonstrate that the ASTM method is not applicable to anisotropic biomaterials such as bone. Rather, it is necessary to develop separate compliance calibration equations for each crack propagation orientation investigated.

Volume effects are a fundamental determinant of structural failure. A material exhibits a volume effect if its failure properties are dependent on the specimen volume. Many brittle ceramics exhibit volume effects due to loading a structure in the presence of "critical" flaws. The number of flaws, their locations, and the effect of stress field within the stressed volume play a role in determining the structure's failure properties. Since real materials are imperfect, structures composed of large volumes of material have higher probabilities of containing a flaw than do small volumes. Consequently, large material volumes tend to fail at lower stresses compared to smaller volumes when tested under similar conditions. Volume effects documented in brittle ceramic and composite structures have been proposed to affect the mechanical properties of bone. We hypothesized that for cortical bone material, (1) small volumes have greater yield strengths than large volumes and (2) that compared to microstructural features, specimen volume was able to account for comparable amounts of variability in yield strength. In this investigation, waisted rectangular, equine third metacarpal diaphyseal specimens (n=24) with nominal cross sections of 3 x 4 mm and gage lengths of either 10.5, 21, or 42 mm, were tested monotonically in tension to determine the effect of specimen volume on their yield strength. Yield strength was greatest in the smallest volume group compared to the largest volume group. Within each group of specimens the logarithm of yield strength was positively correlated with the cumulative failure probability, indicating that the data follow the two-parameter Weibull distribution. Additionally, log yield strength was negatively correlated with log volume, supporting the hypothesis that small stressed volumes of cortical bone possess greater yield strength than similarly tested large stressed volumes.

Background: To compare the stability achieved using two 6.5-mm screws versus two or four 3.5-mm screws for the fixation of a unicondylar distal femur fracture., Methods: A fracture model was created in femoral synthetic composite bones to simulate a lateral femoral condyle fracture (AO/OTA 33-B1). Fixation was performed using three different types of screw constructs: 1) two 6.5-mm cancellous screws inserted using the lag technique, 2) two 3.5-mm cortical screws inserted using the lag technique, and 3) four 3.5-mm cortical screws, with two inserted using the lag technique and two as position screws. After reduction and fixation, the constructs were axially loaded in a material-testing machine. Main outcome measurements were the mean load required to displace the osteotomy site 1 and 2 mm as well as the mean stiffness of the different fixation methods., Results: The 6.5-mm construct required 56% more load to displace the osteotomy fragment 1 mm than the two 3.5-mm construct required (p < 0.0001), and 40% more load than the four 3.5-mm construct required (p < 0.0001). At loads that caused 2 mm of osteotomy displacement, these differences increased to 62% (p < 0.0001) and 48% (p < 0.0001), respectively. The mean loads needed to displace the osteotomy site were 28% higher for 1 mm of displacement (p = 0.003) and 27% higher for 2 mm of displacement (p = 0.03) for the four 3.5-mm screw construct compared with those needed for the two 3.5-mm group. The mean stiffness for the 6.5-mm group (1312.5 N/mm) was significantly higher than for the four 3.5-mm construct (784.2 N/mm; p < 0.0001) and the two 3.5-mm screw construct (409.4 N/mm; p < 0.0001). The difference in stiffness between the 3.5-mm groups was significant as well (p < 0.0001)., Conclusion: Stabilization of a unicondylar distal femur fracture with two 6.5-mm cancellous screws provides the most rigid and stable fixation. If small fragment screws are used, a minimum of four 3.5-mm cortical screws should be used to approximate the mechanical stability of two 6.5-mm screws.

Materials, including bone, often fail due to loading in the presence of critical flaws. The relative amount, location, and interaction of these flaws within a stressed volume of material play a role in determining the failure properties of the structure. As materials are generally imperfect, larger volumes of material have higher probabilities of containing a flaw of critical size than do smaller volumes. Thus, larger volumes tend to fail at fewer cycles compared with smaller volumes when fatigue loaded to similar stress levels. A material is said to exhibit a volume effect if its failure properties are dependent on the specimen volume. Volume effects are well documented in brittle ceramics and composites and have been proposed for bone. We hypothesized that (1) smaller volumes of cortical bone have longer fatigue lives than similarly loaded larger volumes and (2) that compared with microstructural features, specimen volume was able to explain comparable amounts of variability in fatigue life. In this investigation, waisted rectangular specimens (n=18) with nominal cross-sections of 3x4 mm and gage lengths of 10.5, 21, or 42 mm, were isolated from the mid-diaphysis of the dorsal region of equine third metacarpal bones. These specimens were subjected to uniaxial load controlled fatigue tests, with an initial strain range of 4000 microstrain. The group having the smallest volume exhibited a trend of greater log fatigue life than the larger volume groups. Each volume group exhibited a significant positive correlation between the logarithm of fatigue life and the cumulative failure probability, indicating that the data follow the two-parameter Weibull distribution. Additionally, log fatigue life was negatively correlated with log volume, supporting the hypothesis that smaller stressed volumes of cortical bone possess longer fatigue lives than similarly tested larger stressed volumes.

Background Context: Both bone graft and metallic implants have been used in combination with the necessary anterior rod or plate instrumentation to fill the voids left by vertebral body removal, with the ultimate goal of restoring stability. One type of device that has recently been introduced is an expandable titanium telescoping cage that is designed to be used as a strut implant to fill corpectomy defects. The use of these devices has met varying success. Acceptance by surgeons and spine biomechanicians has been limited by clinical failure with subsequent loss of reduction and increase in kyphosis. In order to further improve patient care, it is critical to evaluate the use of these implants through biomechanical as well as other modes of testing., Purpose: To compare and contrast the spinal fusion outcome of using allograft bone versus the expandable vertebral body replacement titanium implant in a lumbar corpectomy procedure., Study Design: Controlled biomechanical study of lumbar spine fusion using bone graft and the expandable cage in an in vivo bovine model after a 4-month postoperative healing period (n=6). ANIMAL MODEL: Twelve Holstein calves aged 4-6 months with L3 and adjacent discs removed to create a simulated lumbar corpectomy defect., Outcome Measures: Lumbar spine stability after corpectomy repair was quantified by biomechanical parameters. Strength of fusion was assessed by stiffness of ex vivo spine specimens in flexion-extension, lateral bending, and torsion obtained from biomechanical testing. Uniaxial strain at various positions on the surface of the anterior plate was measured during loading as an additional stability parameter. Loading tests were repeated after removal of the anterior instrumentation (plate and the screws)., Methods: The calves were randomly allocated to groups for corpectomy defect repair with 1) Allograft metatarsal bone and thoracolumbar spine locking plate, n=6; or 2) Expandable vertebral body replacement device, and thoracolumbar spine locking plate, n=6. After a 4-month postoperative period, anterior-posterior and lateral radiographs were taken of the spine, followed by animal sacrifice and harvesting of the lumbar spine for biomechanical and histological testing. For biomechanical testing, uniaxial strain gauges were applied to the thoracolumbar spine locking plate to measure plate deformation during loading in a custom built fixture for application of flexion-extension, lateral bending, and torsion moments in an Instron materials testing machine. These loading tests were repeated with the thoracolumbar spine locking plate removed, thereby loading solely the fused segment., Results: At 4 months postoperative, the stiffness of the calf spines repaired by the metatarsal allograft and thoracolumbar spine locking plate was significantly greater than that of the spines repaired by the expandable cage and thoracolumbar spine locking plate. This finding was true for all three directions of loading (flexion-extension, left-right lateral bending, and torsion). Concordantly, the neutral zone, elastic zone, and range of motion of the spines repaired with the allograft bone were less than that of the spines repaired with the expandable cage. Greater strain values were observed from the gauges on the thoracolumbar spine locking plate of the spines using the expandable cage than the spines using allograft bone. This finding held for all gauge positions (anterior edge, anterior face, posterior edge, and posterior face at the longitudinal midpoint of the plate). After thoracolumbar spine locking plate removal and a repeat of the loading tests, a decrease in stiffness of the construct and a rise in the motion parameters were observed for both the allograft and cage groups., Conclusions: The use of allograft bone for corpectomy defect repair in the lumbar spine appears to contribute to a stiffer and perhaps more stable spine segment compared with using the expandable cage device for such a repair after a 4-month healing period in this in vivo calf model. These findings thus far are based upon the biomechanical data gathered.

Objective: Malposition of the femoral Less Invasive Stabilization System (LISS) plate may alter its biomechanical behavior. This study compares the mechanical stability of "correctly" affixed LISS plates matching the slope of the lateral femoral condyle to "incorrectly" placed LISS plates fixed in external rotation relative to the distal femur., Methods: A fracture gap model was created to simulate a comminuted supracondylar femur fracture (AO/OTA33-A3). Fixation was achieved using two different plate positions: the LISS plate was either placed "correctly" by internally rotating the plate to match the slope of the lateral femoral condyle, or "incorrectly" by externally rotating the plate relative to the distal femur. Following fixation, the constructs were loaded in axial, torsional, and cyclical axial modes in a material testing machine., Main Outcome Measurement: Stiffness in axial and torsional loading; total deformation and irreversible (plastic) deformation in cyclical axial loading., Results: The mean axial stiffness for the correctly placed LISS constructs was 21.5% greater than the externally rotated LISS constructs (62.7 N/mm vs. 49.3 N/mm; P = 0.0007). No significant difference was found in torsional stiffness between the two groups. Cyclical axial loading caused significantly less (P < 0.0001) plastic deformation in the correct group (0.6 mm) compared with externally rotated group (1.3 mm). All the constructs in the incorrect group failed, where failure was defined as a complete closure of the medial fracture gap, prior to completion of the test cycles., Conclusion: Correct positioning of the LISS plate for fixation of distal femur fractures results in improved mechanical stability as reflected by an increased stiffness in axial loading and decreased plastic deformation at the bone-screw interface.

Background: Percutaneous Achilles tendon lengthening is frequently done to treat gastrocsoleus equinus contracture. To our knowledge, no study has documented the proximity of tendinous or neurovascular structures to the nearest edges of each hemisection in a percutaneous Achilles tendon lengthening, the complication rates related to injury of such structures, or the Achilles tendon rupture rates from inaccurate cuts. Thus, our goal was to document these distances and determine the accuracy of this procedure., Methods: We performed triple-hemisection percutaneous Achilles tendon lengthening (Hoke technique) in 15 cadaver specimens and documented the distance from each cut edge to various relevant anatomical structures. We also documented the accuracy of each cut (diameter of hemisection divided by total tendon diameter), with a reference goal of 50% transection at each level., Results: We found that percutaneous Achilles tendon lengthening is a relatively accurate procedure with hemisections averaging 50% for the middle cut and 60% at the most proximal cut, and 55% at the distal cut. Some tendinous and neurovascular structures are, on average, less than 1 cm from the nearest margin of a given hemisection and are, therefore, at risk. These included the flexor hallucis longus at the middle and proximal cuts (9.1 mm and 5.7 mm, respectively), the tibial nerve at the proximal cut (8.3 mm), and the sural nerve at the middle-lateral cut (7.9 mm)., Conclusion: In cadavers, reasonably accurate cuts can be made, with some vital structures less than 1 cm from the cut tendon.

We hypothesized that recently formed, incompletely mineralized, and thus, relatively deformable osteons in the equine third metacarpus enhance in vitro load-controlled fatigue life in two ways. Macroscopically, there is a compliance effect, because reduced tissue elastic modulus diminishes the stress required to reach a given strain. Microscopically, there is a cement line effect, in which new osteons and their cement lines more effectively serve as barriers to crack propagation. We studied 18 4 x 10 x 100 mm beams from the medial, lateral, and dorsal cortices of metacarpal bones from 6 thoroughbred racehorses. Following load-controlled fatigue testing to fracture in 4 point bending, a transverse, 100 microm thick, basic fuchsin-stained cross-section was taken from the load-bearing region. The number and diameter of all intact (and thus recently formed/compliant) secondary osteons in a 3.8 x 3.8 mm region in the center of the section were determined. The associated area fraction and cement line length of intact osteons were calculated, and the relationships between these variables, elastic modulus (E), and the logarithm of fatigue life (logN(F)) were analyzed. As expected, logN(F) was negatively correlated with E, which was in turn negatively correlated with intact osteon area fraction and density. (LogN(F))/E increased in proportion to intact osteon density and nonlinearly with cement line density (mm/mm(2)). These results support the hypothesis that remodeling extends load-controlled fatigue life both through the creation of osteonal barriers to microdamage propagation and modulus reduction.