Accuracy, readability, and understandability of large language models for prostate cancer information to the public

BACKGROUND

Generative Pretrained Model (GPT) chatbots have gained popularity since the public release of ChatGPT. Studies have evaluated the ability of different GPT models to provide information about medical conditions. To date, no study has assessed the quality of ChatGPT outputs to prostate cancer related questions from both the physician and public perspective while optimizing outputs for patient consumption.

METHODS

Nine prostate cancer-related questions, identified through Google Trends (Global), were categorized into diagnosis, treatment, and postoperative follow-up. These questions were processed using ChatGPT 3.5, and the responses were recorded. Subsequently, these responses were re-inputted into ChatGPT to create simplified summaries understandable at a sixth-grade level. Readability of both the original ChatGPT responses and the layperson summaries was evaluated using validated readability tools. A survey was conducted among urology providers (urologists and urologists in training) to rate the original ChatGPT responses for accuracy, completeness, and clarity using a 5-point Likert scale. Furthermore, two independent reviewers evaluated the layperson summaries on correctness trifecta: accuracy, completeness, and decision-making sufficiency. Public assessment of the simplified summaries' clarity and understandability was carried out through Amazon Mechanical Turk (MTurk). Participants rated the clarity and demonstrated their understanding through a multiple-choice question.

RESULTS

GPT-generated output was deemed correct by 71.7% to 94.3% of raters (36 urologists, 17 urology residents) across 9 scenarios. GPT-generated simplified layperson summaries of this output was rated as accurate in 8 of 9 (88.9%) scenarios and sufficient for a patient to make a decision in 8 of 9 (88.9%) scenarios. Mean readability of layperson summaries was higher than original GPT outputs ([original ChatGPT v. simplified ChatGPT, mean (SD), p-value] Flesch Reading Ease: 36.5(9.1) v. 70.2(11.2), <0.0001; Gunning Fog: 15.8(1.7) v. 9.5(2.0), p < 0.0001; Flesch Grade Level: 12.8(1.2) v. 7.4(1.7), p < 0.0001; Coleman Liau: 13.7(2.1) v. 8.6(2.4), 0.0002; Smog index: 11.8(1.2) v. 6.7(1.8), <0.0001; Automated Readability Index: 13.1(1.4) v. 7.5(2.1), p < 0.0001). MTurk workers (n = 514) rated the layperson summaries as correct (89.5-95.7%) and correctly understood the content (63.0-87.4%).

CONCLUSION

GPT shows promise for correct patient education for prostate cancer-related contents, but the technology is not designed for delivering patients information. Prompting the model to respond with accuracy, completeness, clarity and readability may enhance its utility when used for GPT-powered medical chatbots.

The 3D muscle morphology and intramuscular innervation of the digital bellies of flexor digitorum profundus: Clinical implications for botulinum toxin injection sites

Spasticity of flexor digitorum profundus is frequently managed with botulinum toxin injections. Knowledge of the 3D morphology and intramuscular innervation of the digital bellies of flexor digitorum profundus is necessary to optimize the injections. The purpose of this study was to digitize and model in 3D the contractile and connective tissue elements of flexor digitorum profundus to determine muscle morphology, model and map the intramuscular innervation and propose sites for botulinum toxin injection. Fiber bundles (FBs)/aponeuroses and intramuscular nerve branches were dissected and digitized in 12 formalin embalmed cadaveric specimens. Cartesian coordinate data were reconstructed into 3D models as in situ to visualize and compare the muscle morphology and intramuscular innervation patterns of the bellies of flexor digitorum profundus. The 3rd, 4th and 5th digital bellies were superficial to the 2nd digital belly and located adjacent to each other in all specimens. Each digital belly had distinct intramuscular innervation patterns. The 2nd digital belly received intramuscular branches from the anterior interosseus nerve (AIN). The superior half of the 3rd digital belly was innervated intramuscularly by the ulnar nerve (n = 4) or by both the anterior interosseus and ulnar nerves (n = 1). The inferior half of the belly received dual innervation from the anterior interosseus and ulnar nerves in 2 specimens, or exclusively from the AIN (n = 2) or the ulnar nerve (n = 1). The 4th digital belly was innervated by intramuscular branches of the ulnar nerve. One main branch, after coursing through the 4th digital belly, entered the lateral aspect of the 5th digital belly and arborized intramuscularly. The morphology of the FBs, aponeuroses and intramuscular innervation of the digital bellies of FDP were mapped and modelled volumetrically in 3D as in situ. Previous studies were not volumetric nor identified the course of the intramuscular nerve branches within each digital belly. Based on the intramuscular innervation of each of the digital bellies, one possible optimized botulinum toxin injection location was proposed. This injection location, at the junction of the superior and middle thirds of the forearm, would be located in dense nerve terminal zones of the anterior interosseus and ulnar nerves. Future anatomical and clinical investigations are necessary to evaluate the efficacy of these anatomical findings in the management of spasticity.

Quantification of needle angles for lumbar medial branch denervation targeting the posterior half of the superior articular process: an osteological study

BACKGROUND

Lumbar medial branch radiofrequency ablation (RFA) is a common intervention to manage chronic axial low back pain originating from the facet joints. A more parasagittal approach targeting the posterior half of the lateral neck of superior articular process (SAP) was previously proposed. However, specific needle angles to achieve parallel placement at this target site have not been investigated.

OBJECTIVE

To quantify and compare the needle angles, on posterior and lateral views, to achieve parallel placement of electrodes along the medial branch at the posterior half of the lateral neck of SAP at each lumbar vertebral level (L1-L5) and sacrum.

DESIGN

Osteological Study.

METHODS

Twelve disarticulated lumbosacral spines (n = 72 individual bones) were used in this study. Needles were placed along the periosteum of the posterior half of the lateral neck of SAP, bilaterally and photographed. Mean needle angles for each vertebral level (L1-L5) and sacrum were quantified, and statistical differences were analyzed.

RESULTS

The posterior view provided the degrees of lateral displacement from the parasagittal plane (abduction angle), while the lateral view provided the degrees of declination (cranial-to-caudal angle) of the needle. Mean needle angles at each level varied, ranging from 5.63 ± 5.76° to 14.50 ± 14.24° (abduction angle, posterior view) and 40.17 ± 7.32° to 64.10 ± 9.73° (cranial-to-caudal angle, lateral view). In posterior view, a < 10-degree needle angle interval was most frequently identified (57.0% of needle placements). In lateral view, the 40-50-degree (L1-L2), 50-60-degree (L3-L5), and 60-70-degree (sacrum) needle angle intervals occurred most frequently (54.2%, 50.0%, and 41.7% of needle placements, respectively).

CONCLUSIONS

Targeting the posterior half of the lateral neck of SAP required <10-degree angulation from parasagittal plane in majority of cases. However, variability of needle angles suggests a standard "one-size-fits-all" approach may not be the optimal technique.

Parasagittal needle placement approach for lumbar medial branch denervation: a brief technical report

Radiofrequency denervation of lumbar medial branches is a viable treatment option to manage chronic facetogenic low back pain. Traditionally, lumbar medial branch denervation involves placement of the electrode's active tip at a 20-degree angulation away from the parasagittal plane. However, more recent anatomical studies have provided evidence supporting the feasibility of an alternative parasagittal approach targeting the posterior half of the lateral neck of the superior articular process to capture the lumbar medial branches. Currently, there is a lack of clinical data on the effectiveness of the alternative parasagittal needle placement technique. Therefore, in this brief technical report, the parasagittal needle placement technique and the pain relief outcomes in four consecutive patients following treatment with the parasagittal approach are described.

Innervation of thumb carpometacarpal joint: implications for diagnostic block and denervation procedures

INTRODUCTION

Osteoarthritis (OA) of the thumb carpometacarpal (CMC) joint is a common disorder that negatively impacts hand function. Denervation of the thumb CMC joint has emerged as a viable treatment option. However, the innervation pattern of the thumb CMC joint is controversial. Therefore, the objective of this study was to identify the articular branches supplying the thumb CMC joint and to document their relationship to anatomical landmarks to provide the foundation for image-guided diagnostic block and denervation procedures.

METHODS

In 10 formalin-embalmed upper limb specimens articular branches supplying the thumb CMC joint were dissected from their origin to termination. A frequency map documenting the number of articular branches was generated. The frequency map enabled visualization and comparison of the relative area of innervation of the thumb CMC joint by each articular branch.

RESULTS

The thumb CMC joint received innervation from six nerves. These were the deep branch of ulnar nerve (DBUN), dorsal articular nerve (DAN) of the first interosseus space, thenar branch of median nerve (TBMN), palmar cutaneous branch of median nerve (PCBMN), lateral antebrachial cutaneous nerve (LACN) and superficial branch of the radial nerve (SBRN) and/or their branches. Each nerve was found to innervate different aspects of the joint. The DBUN and DAN were found to innervate the posteromedial aspect of the thumb CMC joint, the TBMN and PCBMN anterior/anteromedial aspects, LACN posterolateral/lateral/anterior aspects and SBRN posterolateral/anterolateral aspects.

CONCLUSIONS

The thumb CMC joint was innervated by articular branches originating from the SBRN, DAN, LACN, PCBMN, TBMN and DBUN. The documented anatomical relationships provide the foundation to inform selective diagnostic block and denervation of the thumb CMC joint. Further investigations are needed to assess the clinical implications of the current study.

Duty-related trauma and PTSD symptoms in US urban firefighters

BACKGROUND

Little is known about the multi-dimensional nature of traumatic duty-related events encountered by firefighters in relation to their post-traumatic stress disorder (PTSD) risk.

AIMS

To describe the types of duty-related events encountered by career firefighters and explore if years in the fire service or total event load moderated the association of trauma exposure to PTSD symptoms.

METHODS

Participants included 755 career, male firefighters (19% of the department's firefighters and 76% of those who accessed the electronic anonymous survey). The Duty-Related Incident Stressors scale was used to assess exposure to 25 potentially traumatic events (event load) and self-appraisal of the stress associated with these events, grouped by type of event (indirect, direct and colleague-related). The Post-Traumatic Stress Disorder Checklist was used to assess PTSD symptoms.

RESULTS

Firefighters rated colleague-related events as the most stressful, followed by indirect and direct events. Event load (r = 0.25) and indirect, direct and colleague-related events stress (r = 0.32-0.35) were positively associated with PTSD symptoms. Results of moderation analyses indicated that event load served as a risk factor in the relation of indirect events stress to PTSD symptoms, and as a buffer in the relation of direct events stress to PTSD symptoms. Years in the fire service were not associated with PTSD symptoms nor moderated the relation of event stress to PTSD symptoms.

CONCLUSIONS

Findings underscored the importance of considering the differential effects that types of duty-related traumatic events and cumulative exposure to trauma may have on firefighters' PTSD symptoms.

Oral histories document community mobilisation to participate in decision-making regarding a hazardous waste thermal treatment facility

Colfax, Louisiana hosts a commercial hazardous waste thermal treatment (TT) facility, which treats fireworks, explosives, and military ordnances by open-burn/open-detonation one mile from the edge of the nearest community. Seventy-one percent of Colfax's residents are Black, and forty-six percent live below poverty, indicating the community's structural vulnerability. This community-based study originated at the behest of Colfax community members. We hypothesized that the close relationships among members of this enclave may have enhanced the community's ability to mobilize in opposition to the TT facility. We conducted semi-structured oral history interviews with nineteen community members and examined the social and interorganizational networks used by the Colfax community to claim its role in decision-making regarding the TT facility after years of exclusion from this process. Interview transcripts were analyzed through the lens of community capacity theory to gain insight into how interactions among community members about the environmental hazards led to social mobilization and improved participation in the decision-making process using codes for communication, organization, and outcome. Additionally, we reviewed Louisiana Department of Environmental Quality records for complaints about the facility to gauge public participation. One notable theme across several interviews was exclusion from the initial decision-making process related to the facility. However, interviewees noted a sustained effort was made among community members to educate themselves about the facility, organize a response through neighbor-to-neighbor contact, and take action by submitting formal complaints and participating in public hearings. Through the lens of environmental justice, this study illustrates an evolving condition of procedural justice.

Dissection, digitization, and three-dimensional modelling: a high-fidelity anatomical visualization and imaging technology

Technological advances have enabled the development of a novel technique of dissection, digitization and three-dimensional modelling of skeletal muscle and other tissues including neurovascular structures as in situ over the last 25 years. Meticulous serial dissection followed by digitization is used to collect Cartesian coordinate data of the contractile and connective tissue elements throughout the entire muscle volume. The Cartesian coordinate can then be used to construct high-fidelity three-dimensional models that capture the spatial arrangement of the contractile and connective tissue elements as in situ enabling detailed studies of the arrangement of the fiber bundles and their attachment sites to aponeuroses, tendon, and bone. In the laboratory, we have concurrently developed a computational methodology to quantify architectural parameters, including fiber bundle length, pennation angle, volume, physiological cross-sectional area in three-dimensional space. In this paper, a flexor digitorum superficialis specimen will be used to demonstrate the high-fidelity outcomes of dissection, digitization, and three-dimensional modelling. This three-step methodology provides a unique opportunity to study muscle architecture in three dimensions, as in situ. Knowledge translation from the anatomy laboratory to the clinical setting has been highly successful.

Quantification of Needle Angles for Traditional Lumbar Medial Branch Radiofrequency Ablation: An Osteological Study

BACKGROUND

Clinical outcomes following lumbar medial branch radiofrequency ablation (RFA) have been inconsistent. One possible reason is less-than-optimal placement of the electrode along the medial branch at the lateral neck of superior articular process (SAP). Needle angles that define optimal placement (i.e., parallel to the medial branch) may be helpful for consistent technical performance of RFA. Despite its importance, there is a lack of anatomical studies that quantify RFA needle placement angles.

OBJECTIVE

To quantify and compare needle angles to achieve parallel placement along the medial branch as it courses on the middle two-quarters of the lateral neck of the SAP at the L1-L5 vertebrae.

DESIGN

Osteological Study.

METHODS

Ten lumbar vertebral columns were used in this study. Needles were placed along the periosteum of the middle two-quarters of the lateral neck of SAP. Mean needle angles for L1-L5 were quantified and compared using posterior (n = 100) and lateral (n = 100) photographs.

RESULTS

Mean needle angles varied ranging from 29.29 ± 17.82° to 47.22 ± 16.27° lateral to the parasagittal plane (posterior view) and 33.53 ± 10.23° to 49.19 ± 10.69° caudal to the superior vertebral endplate (lateral view). Significant differences in mean angles were found between: L1/L3 (P = .008), L1/L4 (P = .003), and L1/L5 (P = .040) in the posterior view and L1/L3 (P = .042), L1/L4 (P < .001), L1/L5 (P < .001), L2/L4 (P = .004), and L2/L5 (P = .004) in lateral view.

CONCLUSIONS

Variability of needle angles suggest a standard "one-size-fits-all" approach may not be the optimal technique. Future research is necessary to determine optimal patient-specific needle angles from a more detailed and granular analysis of fluoroscopic landmarks.

Intramuscular aponeuroses and fiber bundle morphology of the five bellies of flexor digitorum superficialis: A three-dimensional modeling study

Restoring balanced function of the five bellies of flexor digitorum superficialis (FDS) following injury requires knowledge of the muscle architecture and the arrangement of the contractile and connective tissue elements. No three-dimensional (3D) studies of FDS architecture were found in the literature. The purpose was to (1) digitize/model in 3D the contractile/connective tissue elements of FDS, (2) quantify/compare architectural parameters of the bellies and (3) assess functional implications. The fiber bundles (FBs)/aponeuroses of the bellies of FDS were dissected and digitized (MicroScribe® Digitizer) in 10 embalmed specimens. Data were used to construct 3D models of FDS to determine/compare the morphology of each digital belly and quantify architectural parameters to assess functional implications. FDS consists of five morphologically and architecturally distinct bellies, a proximal belly, and four digital bellies. FBs of each belly have unique attachment sites to one or more of the three aponeuroses (proximal/distal/median). The proximal belly is connected through the median aponeurosis to the bellies of the second and fifth digits. The third belly exhibited the longest mean FB length (72.84 ± 16.26 mm) and the proximal belly the shortest (30.49 ± 6.45 mm). The third belly also had the greatest mean physiological cross-sectional area, followed by proximal/second/fourth/fifth. Each belly was found to have distinct excursion and force-generating capabilities based on their 3D morphology and architectural parameters. Results of this study provide the basis for the development of in vivo ultrasound protocols to study activation patterns of FDS during functional activities in normal and pathologic states.

Anatomical study of the medial branches of the lumbar dorsal rami: implications for image-guided intervention

INTRODUCTION

Fluoroscopic-guided radiofrequency ablation of the lumbar medial branches is commonly performed to manage chronic low back pain originating from the facet joints. A detailed understanding of the course of medial branches in relation to bony and soft tissue landmarks is paramount to optimizing lumbar denervation procedures, particularly parallel placement of the radiofrequency electrode. The objectives of this study were to investigate the relationship of medial branches to anatomical landmarks and discuss the implications for lumbar denervation.

METHODS

Ten cadaveric specimens were meticulously dissected. The origin, course, and relationship of lumbar medial branches to bony and soft tissue landmarks were documented.

RESULTS

The medial branches followed the lateral neck of superior articular process deep to the intertransversarii mediales muscle at each lumbar vertebral level. In all specimens, the medial branches coursed laterally on the anterior half of the neck and transitioned from parasagittal-to-medial on the posterior half to reach the mamillo-accessory notch. The mamillo-accessory ligament was found to not occlude the nerve on the posterior quarter of the lateral neck but rather at the mamillo-accessory notch located at the posterior margin of the superior articular process.

DISCUSSION

A detailed understanding of the relationship of medial branches to anatomical landmarks is essential to optimizing needle placement for lumbar denervation procedures. The current study suggests that a parasagittal placement, with increased cranial-to-caudal angulation of the electrode, may improve parallel tip alignment with the targeted medial branch and represent a potential alternative to the traditional technique.

Overview of the Innervation of Ankle Joint

In this article, the literature describing the origin, course, and termination of the nerves innervating the ankle joint is reviewed and discussed. The anterior aspect of the joint capsule receives innervation from articular branches from the saphenous, superficial, and deep fibular nerves; laterally from the sural and superficial fibular nerves; and medially and posteriorly from the saphenous and tibial nerves. Comprehensive mapping of the trajectory, spatial relationships, and termination of the articular branches innervating the ankle joint capsule will aid in developing new and improving existing image-guided nerve block and radiofrequency ablation protocols to treat chronic joint pain.

Overview of Innervation of Knee Joint

Image-guided diagnostic block and radiofrequency ablation of the knee joint to manage pain require detailed understanding of joint innervation in relation to soft tissue and bony landmarks. In this article, the origin, course, and relationship to anatomic landmarks of articular nerves supplying the knee joint are discussed. The innervation pattern of the anterior and posterior aspects of the knee joint capsule is relatively consistent, with some variation in supply by the saphenous, anterior division of obturator, and common fibular nerves. To improve nerve capture rates for diagnostic block and radiofrequency ablation, multiple target sites could be beneficial.

Overview of Innervation of Shoulder and Acromioclavicular Joints

Detailed understanding of the course and location of articular nerves supplying the shoulder joint is paramount to the successful utilization of image-guided radiofrequency ablation to manage chronic shoulder pain. In this article, the origin, course, and relationship to anatomic landmarks of articular nerves supplying the shoulder and acromioclavicular joints are discussed. The shoulder joint capsule was consistently reported to receive innervation from multiple sources including the suprascapular, axillary, subscapular, and lateral pectoral nerves. The acromioclavicular joint received innervation from suprascapular and lateral pectoral nerves. The consistent relationship of articular branches to anatomic landmarks provides the basis for specific image-guided targeting.

Swelling-Assisted Sequential Infiltration Synthesis of Nanoporous ZnO Films with Highly Accessible Pores and Their Sensing Potential for Ethanol

Here, we report a swelling-assisted sequential infiltration synthesis (SIS) approach for the design of highly porous zinc oxide (ZnO) films by infiltration of block copolymer templates such as polystyrene-block-polyvinyl pyridine with inorganic precursors followed by UV ozone-assisted removal of the polymer template. We show that porous ZnO coatings with the thickness in the range between 140 and 420 nm can be obtained using only five cycles of SIS. The pores in ZnO fabricated via swelling-assisted SIS are highly accessible, and up to 98% of pores are available for solvent penetration. The XPS data indicate that the surface of nanoporous ZnO films is terminated with -OH groups. Density functional theory calculations show a lower energy barrier for ethanol-induced release of the oxygen restricted depletion layer in the case of the presence of -OH groups at the ZnO surface, and hence, it can lead to higher sensitivity in sensing of ethanol. We monitored the response of ZnO porous coatings with different thicknesses and porosities to ethanol vapors using combined mass-based and chemiresistive approaches at room temperature and 90 °C. The porous ZnO conformal coatings reveal a promising sensitivity toward detection of ethanol at low temperatures. Our results suggest the excellent potential of the SIS approach for the design of conformal ZnO coatings with controlled porosity, thickness, and composition that can be adapted for sensing applications.

Ultrasound-guided diagnostic IPACK as a valuable tool in the management of a patient with soleal sling syndrome: a doubly rare case report

This article describes the use of an infiltration between the popliteal artery and capsule of the knee joint (IPACK) to diagnose an entrapment neuropathy of the tibial nerve (TN) in a patient presenting with chronic neuropathic pain in the medial posterior compartment of the left knee, with a previous electromyography showing no evidence of tibial or common peroneal nerve neuropathy. After a positive sciatic nerve block, the patient was evaluated for a TN block, cancelled due to the presence of an abnormal leash of vessels wrapping around the nerve. For this reason, the patient was submitted to a diagnostic IPACK. A negative IPACK suggested that a compression of the TN at the popliteal fossa was the most likely source of the symptoms. After surgical decompression of the TN nerve at the popliteal fossa, the patient's symptoms decreased substantially.

Revisiting the Genicular Nerve Block: An Up-to-Date Guide Utilizing Ultrasound Guidance and Peripheral Nerve Stimulation - Anatomy Description and Technique Standardization

BACKGROUND

Over the last decade, several authors have reported that percutaneous peripheral nerve stimulation (PNS) can be used to assist in verifying the position of the procedure needle tip in relation to nerve structures, and that the combined technique using both ultrasound (US) guidance and PNS may serve as a reliable method for confirmation of the correct position of the procedure needle tip. It has also been reported that, when combined with US guidance, PNS may increase the success rate of pain management interventions.

OBJECTIVES

The aim of this technical report was to standardize an effective and easy to learn illustrated step-by-step technical approach to nerve identification during US-guided genicular nerve blocks, using percutaneous PNS as a verification instrument for procedure needle tip location.

STUDY DESIGN

This technical protocol was developed based on the results of the authors' most recent cadaveric study on the innervation of the knee joint capsule. The technique was developed and tested by 4 different interventionists with different levels of expertise in US-guided procedures.

SETTING

The cadaveric study of the knee joint capsule innervation was performed at the laboratory of the Division of Anatomy of one institution. The technical protocol using US and PNS was later developed at the medical simulation center of a different institution.

METHODS

A team of anatomists from a division of anatomy of one institution performed the cadaveric study on the innervation of the knee joint capsule. A team of physicians then developed the step-by-step approach to this technical protocol at the medical simulation center of  a different institution. Finally, the illustrated step-by-step approach was tested by 4 different interventionists with different levels of expertise in US-guided procedures (1 beginner-level user; 1 intermediate-level user; 2 expert-level users), using a portable percutaneous PNS and 2 different US transducers at 2 different institutions.

RESULTS

This technical protocol was successfully developed based on the results of the cadaveric study on the innervation of the knee joint capsule. Additionally, it was later successfully tested by interventionists with various levels of expertise utilizing different US equipment at separate institutions.

LIMITATIONS

By combining US and nerve stimulation, this protocol requires the availability of both US equipment and necessary equipment for nerve stimulation that must all be made available in the sterile field. Another potential disadvantage is that nerve stimulation controls and the US image screen are generally located on 2 separate display panels, which could cause difficulty with visualization and simultaneous calibration for 2 individual devices.

CONCLUSIONS

Our illustrated step-by-step technical protocol can be effectively and safely utilized as a reliable method of training, by which physicians with little to moderate US experience can improve their skills in accurately identifying the genicular nerves while performing US-guided examinations with the intent of executing a peripheral nerve block.

Diagnostic block and radiofrequency ablation of the acromial branches of the lateral pectoral and suprascapular nerves for shoulder pain: a 3D cadaveric study

BACKGROUND AND OBJECTIVES

Acromial branches of the lateral pectoral and suprascapular nerves have been proposed as targets for diagnostic block and radiofrequency ablation to treat superior shoulder pain; however, the nerve capture rates of these procedures have not been investigated. The objectives of this study were to use dissection and 3D modeling technology to determine the course of these acromial branches, relative to anatomical landmarks, and to evaluate nerve capture rates using ultrasound-guided dye injection and lesion simulation.

METHODS

Ultrasound-guided dye injections, targeting the superior surface of coracoid process and floor of supraspinous fossa, were performed (n=5). Furthermore, needles targeting the superior and posterior surfaces of the coracoid process were placed under ultrasound guidance to simulate needle electrode position (n=5). Specimens were dissected, digitized, and modeled to determine capture rates of acromial branches of lateral pectoral and suprascapular nerves.

RESULTS

The course of acromial branches of lateral pectoral and suprascapular nerves were documented. Dye spread capture rates: acromial branches of lateral pectoral and suprascapular nerves were captured in all specimens. Lesion simulation capture rates: (1) when targeting superior surface of coracoid process, the entire acromial branch of lateral pectoral nerve was captured in all specimens and (2) when targeting posterior surface of coracoid process, the acromioclavicular and bursal branches of acromial branch of suprascapular nerve were captured in all specimens; coracoclavicular branch was captured in 3/5 specimens.

CONCLUSIONS

This study supports the anatomical feasibility of ultrasound-guided targeting of the acromial branches of lateral pectoral and suprascapular nerves. Further clinical investigation is required.

Cardiometabolic disease, comorbidities and risk of death: findings using data from large-scale electronic health records

Background

Myocardial infarction (MI), stroke and diabetes are separately associated with increased risk of mortality but it is uncertain if their combined effects are proportional, amplified or less than the expected risk of each disease individually. In addition, patients with these conditions tend to also have other long-term comorbidities. How the relationship between cardiometabolic disease and risk of death is modified by the presence of comorbidity is unclear.

Purpose

We investigated the separate and combined effects of MI, stroke and diabetes on all-cause mortality, and examined the impact of comorbidity on these associations.

Methods

We selected a patient cohort of 2,007,731 (51% women) aged ≥16 years at registration with their general practice, using large-scale UK primary care electronic health records that were linked to the national death registry. We identified patients with a recorded diagnosis of MI, stroke, diabetes or none before 2005 (baseline), and classified the patient cohort into mutually exclusive categories of their baseline disease status. For each group, we also extracted information on another major 53 long-term conditions prior to baseline. The cohort was followed until death, deregistration from the practice or censored at the end of study (31 Dec 2014). We used Cox regression, and tested for departure from additivity and multiplicativity to assess interaction.

Results

At baseline, the mean age of the cohort was 51 (SD=18) years and 7% (N=145,910) had a cardiometabolic disease. Over an average follow-up of 7 (SD=3) years, 270,036 died (mean age of death=79 years). After adjusting for baseline age and sex, the hazard ratio (HR) (95% confidence interval [CI]), relative to those without cardiometabolic disease, were as follows: diabetes=1.53 (1.51 to 1.55), MI=1.54 (1.51 to 1.56), stroke=1.87 (1.84 to 1.90), diabetes and MI=2.16 (2.09 to 2.23), MI and stroke=2.39 (2.28 to 2.49), diabetes and stroke=2.56 (2.47 to 2.65), and all three=3.17 (2.95 to 3.41). After adjusting for the 53 comorbidities, the HR (95% CI) were attenuated: diabetes=1.37 (1.35 to 1.39), MI=1.25 (1.23 to 1.27), stroke=1.49 (1.46 to 1.52), diabetes and MI=1.60 (1.55 to 1.65), MI and stroke=1.52 (1.45 to 1.59), diabetes and stroke=1.91 (1.84 to 1.98), and all three=1.77 (1.64 to 1.91). The results did not materially changed with adjustment for smoking and deprivation level. Test for interaction revealed some minor synergistic effects when cardiometabolic disease co-occurred but excess risks were lower than expected for two combined vs individual disease effects; no significant interaction was seen for all three vs individual disease effects.

Conclusion

MI, stroke and diabetes are associated with excess mortality, which was partly due to associated chronic conditions. We found no evidence that the co-occurrence of these three conditions contribute to a higher excess mortality than expected from each of them separately.

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): NIHR Oxford Biomedical Research Centre; Oxford Martin School, University of Oxford

Association between comorbidities and blood pressure trajectories in patients with hypertension

Background

Our knowledge of how to better manage elevated blood pressure in presence of comorbidities is limited; in part due to exclusion or underrepresentation of multimorbid patients from major clinical trials.

Purpose

To investigate the burden and types of comorbidities in patients with hypertension, to assess how such comorbidities and other variables affect blood pressure levels over time.

Methods

The study was conducted using linked electronic health records from the UK Clinical Practice Research Datalink study from its inception on 1 January 1985 to 30 September 2015. Using linked electronic health records, we compared systolic blood pressure levels among 295,487 patients with diagnosed hypertension by type and numbers of major comorbidities from at least 5 years before to up to 10 years after hypertension diagnosis. We used a multiple landmark cohort design in order to investigate associations prospectively with time-updated information that takes advantage of the dynamic nature of electronic health records.

Results

Time-updated multivariable linear regression analyses showed that the presence of more comorbidities was independently associated with lower blood pressure during follow-up. This negative association was not specific to particular types of comorbidities; although associations were stronger in those with pre-existing cardiovascular disease. Tracking patients backwards to years prior to hypertension diagnosis revealed that the association between comorbidities and blood pressure were even more pronounced in years before hypertension diagnosis. Despite substantial declines in blood pressure in the first year after diagnosis, subsequent changes were modest, with no evidence of a more rapid decline in those with more or specific types of comorbidities.

Conclusions

Blood pressure levels at which patients were diagnosed with hypertension varied substantially and were lower when patients had more comorbidities. This early selection bias was a key determinant of long-term differences in blood pressure by comorbidity status and provides an additional explanation for the lower blood pressure in multimorbid patients.

Mean SBP (mmHg) over time

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): National Institute for Health Research Oxford Biomedical Research Centre, Rhodes Trust and Clarendon Fund

Evaluation of nerve capture using classical landmarks for genicular nerve radiofrequency ablation: 3D cadaveric study

Background and objectives

Radiofrequency (RF) denervation of the superolateral genicular nerve (SLGN), superomedial genicular nerve (SMGN) and inferomedial genicular nerve (IMGN) is commonly used to manage chronic knee joint pain. However, knowledge of articular branches captured, using classical landmarking techniques, remains unclear. In order to enhance and propose new RF procedures that conceivably capture a greater number of articular branches, more detailed cadaveric investigation is required. The objectives were to (1) determine which articular branches are captured or spared using classical landmarking techniques, and (2) evaluate the anatomical feasibility of classical landmarking techniques using three-dimensional (3D) modeling technology.

Methods

Ultrasound-guided classical superolateral/superomedial/inferomedial landmarking techniques were used to position RF cannulae in five specimens. The articular branches, bony and soft tissue landmarks, and cannula tip position, were meticulously dissected, digitized and modeled in 3D. Simulated lesions were positioned at the cannula tip, on the 3D models, to determine which articular branches were captured or spared. Capture rates of articular branches were compared.

Results

In all specimens, classical superolateral/superomedial techniques captured the transverse deep branches of SLGN and SMGN, and articular branches of lateral and medial nerve to vastus intermedius, while sparing distal branches of SLGN/SMGN. The inferomedial technique captured anterior branches of IMGN while sparing the posterior and inferior branches.

Conclusions

This study provides anatomical evidence supporting the effectiveness of classical landmarking for genicular nerve ablation; however, each technique resulted in sparing of articular branches. The extensive innervation of the knee joint suggests the use of supplementary landmarks to improve capture rates and potentially patient outcomes.

Association between traumatic brain injuries and ketamine infusion side effects following combat injury

INTRODUCTION

Ketamine is a vital component for acute pain management in emergency trauma care for both civilian and military hospitals. This preliminary analysis examined whether combat-injured US service members sustaining traumatic brain injuries (TBI) experienced increased odds of ketamine side effects compared with those without TBI.

METHODS

This preliminary analysis included combat-injured service members, ages ≥18 years with documented pain scores during the 24 hours before and 48 hours after receiving an intravenous ketamine infusion at Walter Reed National Military Medical Center (WRNMMC) between 2007 and 2014. Logistic regression modeling examined the association between TBI and ketamine side effects (eg, hallucinations, nightmares, dysphoria, nausea, decreased oxygen saturation) during hospitalisation.

RESULTS

Of the 77 patients, 62% presented with a documented TBI. Side effects were documented for 18.8% of those without TBI and 24.4% of those with TBI. Analyses were unable to find evidence against the null hypothesis with the current sample size, even when adjusting for injury characteristics and preinfusion opioid doses (adjusted OR=0.90 (95% CI 0.26 to 3.34), p=0.87).

CONCLUSION

In this small sample of combat-injured service members, we were unable to detect a difference in ketamine-related side effects by documented TBI status. These hypothesis-generating findings support the need for future studies to examine the use of intravenous ketamine infusions for pain management, and subsequent care outcomes in patients who experience polytraumatic trauma inclusive of TBI.

PTSD symptoms and suicidal ideation in US female firefighters

BACKGROUND

Little is known regarding the mental health of women firefighters.

AIMS

To identify demographic, work-related and mental health characteristics associated with post-traumatic stress disorder (PTSD) symptoms and lifetime suicidal ideation in female firefighters compared with male colleagues.

METHODS

Participants were firefighters (75 women and 2564 men) employed in a large urban fire department in the USA. Chi-square, correlations, t-tests and analyses of variance were conducted to examine the predictors of PTSD symptoms and lifetime suicide ideation in men and women.

RESULTS

Approximately 20% of women scored positively for PTSD and 30% reported lifetime suicidal ideation. Women with PTSD symptoms were more likely to be in their mid-career years (11-20) than in their first 10 years (87% versus 44%; χ2 = 8.77, P < 0.05) and to have received counselling (53% versus 14%; χ2 = 8.11, P < 0.01). Being single (73% versus 58%; χ2 = 6.02, P < 0.05), having a second job (68% versus 38%; χ2 = 5.79, P < 0.05) and having received counselling (41% versus 11%; χ2 = 8.51, P < 0.01) predicted suicide ideation. Depression and general stress positively predicted PTSD symptoms and suicide ideation. PTSD also predicted suicide ideation.

CONCLUSIONS

Compared to male firefighters, women were at high risk for PTSD symptoms and suicide ideation. Particularly for women, few socio-demographic and work-related variables were associated with these outcomes. Mental health variables predicted depression and suicide ideation for both gender groups. Therefore, in screening and intervention efforts, it may be most fruitful to focus on mental health risk correlates of PTSD and suicide ideation.

Parent and Provider Perspectives on Recently Incarcerated Youths' Access to Healthcare During Community Reentry

Incarcerated youth have numerous healthcare needs, yet access to healthcare following community reentry is limited. Healthcare and juvenile justice providers, along with parents, strongly influence access to care for youth undergoing reentry. However, their perspectives are often missing from the literature. We examined parent and provider perspectives on youths' access to healthcare during community reentry. We conducted 72 longitudinal interviews with parents of youth undergoing reentry (n= 34 parents) and cross-sectional interviews with health and juvenile justice providers (n=20 providers). We performed inductive analysis of interview transcripts to identify the major themes related to access to healthcare during reentry. Respondents identified key leverage points that influence access to healthcare along the spectrum of individual, community, and policy-level factors. Parent and provider perspectives demonstrated substantial overlap, strongly concurring on the essential role of parents in linking youth to care and the external factors that limit parents' ability to connect youth to care. However, providers discussed parents not buying-in to treatment plans as a barrier to care, and parents uniquely described feeling powerless when their children were not motivated to receive care. Parents and providers agreed on priority solutions for improving care access during reentry. Immediate solutions centered on: 1) increasing reliability and continuity of providers, 2) providing free or low-cost transportation to healthcare visits, and 3) eliminating gaps in Medicaid coverage post-incarceration. Findings also signal the broader need to pursue strategies that increase family engagement in healthcare during reentry. In doing so, health and juvenile justice providers can partner with parents to overcome barriers to healthcare for youth during reentry.

Key Population Health Outcomes for Children with Medical Complexity: A Systematic Review

INTRODUCTION

Despite the significant healthcare policy and program implications, a summary measure of health for children with medical complexity (CMC) has not been identified. It is unclear whether existing population health approaches apply to CMC. We conducted a systematic review of the existing peer-reviewed research literature on CMC to describe the health outcomes currently measured for CMC.

METHODS

We searched MEDLINE and PsycINFO by linking combinations of key words from three groups of concepts: (1) pediatric, (2) medical complexity, and (3) chronicity or severity. Study eligibility criteria were research studies including CMC with any outcome reported. Data on the outcomes were systematically extracted. Iterative content analysis organized outcomes into conceptual domains and sub-domains.

RESULTS

Our search yielded 3853 articles. After exclusion criteria were applied, 517 articles remained for data extraction. Five distinct outcome domains and twenty-four sub-domains emerged. Specifically, 50% of the articles studied healthcare access and use; 43% family well-being; 39% child health and well-being; 38% healthcare quality; and 25% adaptive functioning. Notably lacking were articles examining routine child health promotion as well as child mental health and outcomes related to family functioning.

CONCLUSIONS

Key health domains for CMC exist. Adaptations of existing sets of metrics and additional tools are needed to fully represent and measure population health for CMC. This approach may guide policies and programs to improve care for CMC.

Evaluation of the proximal adductor canal block injectate spread: a cadaveric study

BACKGROUND AND OBJECTIVES

Quadriceps sparing adductor canal block has emerged as a viable intervention to manage pain after total knee arthroplasty. Recent studies have defined ultrasound (US) landmarks to localize the proximal and distal adductor canal. US-guided proximal adductor canal injection has not been investigated using these sonographic landmarks. The objectives of this cadaveric study were to evaluate dye injectate spread and quantify the capture rates of nerves supplying articular branches to the knee joint capsule using a proximal adductor canal injection technique.

METHODS

A US-guided proximal adductor canal injection with 10 mL of dye was performed in seven lightly embalmed specimens. Following injection, specimens were dissected to document dye spread and frequency of nerve staining.

RESULTS

Following proximal adductor canal injection, dye spread consistently stained the deep surface of sartorius, vastoadductor membrane, aponeurosis of the vastus medialis obliquus, and adductor canal. The saphenous nerve, posteromedial branch of nerve to vastus medialis, superior medial genicular nerve and genicular branch of obturator nerve were captured in all specimens at the proximal adductor canal. There was minimal to no dye spread to the distal femoral triangle, anterior division of the obturator nerve and anterior branches of nerve to vastus medialis.

CONCLUSIONS

This anatomical study provides some insights into the mechanism of analgesia to the knee following a proximal adductor canal injection and its motor sparing properties. Further clinical investigation is required to confirm cadaveric findings.

P1548Long-term past, current and usual systolic blood pressure and incident cardiovascular disease: risk prediction using large-scale, routinely recorded clinical data

Background

The impact of long-term exposure to elevated systolic blood pressure (SBP) on future cardiovascular disease (CVD) in “real-world” settings, and its relevance to risk prediction, are less investigated.

Purpose

To examine the risk of incident CVD in relation to long-term past, current, and usual SBP, and compare their predictive performance, using evidence from large-scale electronic health records (EHR).

Methods

Using data extracted from UK primary care linked EHR, we applied a landmark cohort study design, by including patients aged 40 (N≈64,000), 50 (N≈80,000) and 60 (N≈67,000) years (y) at study entry who had recorded SBP and with no prior CVD or previous antihypertensive or lipid-lowering prescriptions at baseline. We estimated past SBP (mean, time-weighted mean, and variability recorded up to 10 years prior to baseline) and usual SBP (correcting current values for past time-dependent SBP variability). We used Cox regression to estimate hazard ratio (HR), and applied Bayesian analysis within a machine learning framework in developing and validating models. To evaluate predictive performance of the models, we used discrimination (area under the curve [AUC]) and calibration metrics. The outcome was incident CVD (first hospitalisation for or death from coronary heart disease or stroke/transient ischaemic attack). Analyses were conducted separately for each age cohort.

Results

After a mean follow-up of 8 years, the numbers of patients who developed incident CVD were over 1000 (40y), 3000 (50y) and 5000 (60y). Higher past, current and usual SBP values were separately and independently associated with increased incident CVD risk. Per 20-mmHg rise in SBP, the HR (95% credible interval [CI]) for current SBP for ages 40, 50 and 60 years were 1.18 (1.08 to 1.26), 1.22 (1.18 to 1.30) and 1.22 (1.19 to 1.24); the corresponding HR were stronger in magnitude for past SBP (mean and time-weighted mean) and usual SBP (HR ranged from: 40y=1.31 to 1.41, 50y=1.39 to 1.45 and 60y=1.32 to 1.48). For each age cohort, the AUC (95% CI) for the model that included current SBP, sex, smoking, deprivation, diabetes and lipid profile in the validation sample were: 40y=0.739 (0.730 to 0.746), 50y=0.750 (0.716 to 0.810), and 60y=0.647 (0.642 to 0.658). Adding past SBP mean, time-weighted mean or variability to this model were associated with modest increases in the AUC and all models showed good calibration. Small improvements in the AUC were similarly observed when evaluating models separately for men and women within each age cohort.

Conclusion

Using multiple SBP recordings from patients' EHR showed stronger associations with incident CVD than a single SBP measurement, but their addition to multivariate risk prediction models had negligible effects on model performance.

Acknowledgement/Funding

Oxford Martin School and National Institute for Health Research Oxford Biomedical Research Centre

Evaluation of suprascapular nerve radiofrequency ablation protocols: 3D cadaveric needle placement study

BACKGROUND AND OBJECTIVES

Image-guided intervention of the suprascapular nerve is a reported treatment to manage chronic shoulder joint pain. The suprascapular nerve is conventionally targeted at the suprascapular notch; however, targeting of its branches, the medial and lateral trunks, which are given off just posterior to the notch has not been considered. Since the lateral trunk supplies the posterior supraspinatus and articular branches to the glenohumeral joint capsule, while the medial trunk provides motor innervation to the anterior region, it may be possible to preserve some supraspinatus activation if the medial trunk is spared. The main objective was to investigate whether midpoint between suprascapular and spinoglenoid notches is the optimal target to capture articular branches of lateral trunk while sparing medial trunk.

METHODS

In 10 specimens, using ultrasound guidance, one 17 G needle was placed at the suprascapular notch and a second at midpoint between suprascapular and spinoglenoid notches. The trunks and needles were exposed in the supraspinous fossa, digitized and modeled in 3D. Lesion volumes were added to the models to asses medial and lateral trunk capture rates. Mean distance of needle tips to origin of medial trunk was compared.

RESULTS

Conventional notch technique captured both lateral and medial trunks, whereas a midpoint technique captured only lateral trunk. Mean distance of needles from the origin of medial trunk was 5.10±1.41 mm (notch technique) and 14.99±5.53 mm (midpoint technique).

CONCLUSIONS

The findings suggest that the midpoint technique could spare medial trunk of suprascapular nerve, while capturing lateral trunk and articular branches. Further clinical investigation is required.

Evaluation of the iPACK block injectate spread: a cadaveric study

BACKGROUND AND OBJECTIVES

Ultrasound-guided infiltration of the interspace between the popliteal artery and capsule of the knee (iPACK) block, a new regional analgesic technique, is believed to relieve posterior knee pain, after total knee arthroplasty, by targeting the articular branches innervating posterior aspect of the joint. The extent of injectate spread and the number of articular branches affected is currently unknown. This cadaveric study aimed to compare the area of dye spread and frequency of articular branches staining following a proximal versus distal injection technique.

METHODS

An ultrasound-guided iPACK injection (10 mL of methylene blue dye solution) was performed in 14 lightly embalmed specimens: 7 injected using a proximal injection technique (1 fingerbreadth above base of patella) and 7 using a distal injection technique (at the superior border of the femoral condyles). Following injection, dissection, digitization, and 3D modeling were performed to map the area of dye spread and determine the frequency of nerve staining.

RESULTS

Both injection techniques achieved a similar mean area of injectate spread. Of the four articular branches supplying the posterior knee joint capsule, the genicular branch of posterior division of obturator nerve was stained in all specimens. The proximal injection resulted in staining of superior medial genicular nerve, due to dye spread through the adductor hiatus, whereas superior lateral genicular nerve and anterior branch of common fibular nerve were consistently stained following distal injection. Other articular branches were stained with variable frequency.

CONCLUSIONS

Both proximal and distal iPACK injection techniques provided a similar area of dye spread in the popliteal region and extensive staining of the articular branches supplying the posterior capsule. The proximal injection technique promoted greater anteromedial dye spread, while the distal injection had more anterolateral spread. Further clinical study is required to confirm our cadaveric findings. .

Oral health behaviours of older Australian men: the Concord Health and Ageing in Men Project

BACKGROUND

The Concord Health and Ageing in Men Project (CHAMP) is a cohort study of the health of a representative sample of older Australian men. The aim of this paper is to describe the oral health behaviours and dental service use of CHAMP participants and explore associations between oral health behaviours with and general health status.

METHOD

Information collected related to socio-demographics, general health, oral health service-use and oral health behaviours. Key general health conditions were ascertained from the health questionnaire and included physical capacity and cognitive status.

RESULTS

Fifty-seven percent of the men reported visiting a dental provider at least once or more a year and 56.7% did so for a "dental check-up". Of those with some natural teeth, 59.3% claimed to brush their teeth at least twice or more a day. Most men (96%) used a standard fluoride toothpaste. Few participants used dental floss, tooth picks or mouth-rinses to supplement oral hygiene. Cognitive status and self-rated general health were associated with dental visiting patterns and toothbrushing behaviour.

CONCLUSIONS

Most older men in CHAMP perform favourable oral health behaviours. Smoking behaviour is associated with less favourable dental visiting patterns, and cognitive status with toothbrushing behaviour.