A predictive model for the critical shoulder angle based on a three-dimensional analysis of scapular angular and linear morphometrics.

BACKGROUND: The purpose of this study was to define the features of scapular morphology that are associated with changes in the critical shoulder angle (CSA) by developing the best predictive model for the CSA based on multiple potential explanatory variables, using a completely 3D assessment. METHODS: 3D meshes were created from CT DICOMs using InVesalius (Vers 3.1.1, RTI [Renato Archer Information Technology Centre], Brazil) and Meshmixer (3.4.35, Autodesk Inc., San Rafael, CA). The analysis included 17 potential angular, weighted linear and area measurements. The correlation of the explanatory variables with the CSA was investigated with the Pearson's correlation coefficient. Using multivariable linear regression, the approach for predictive model-building was leave-one-out cross-validation and best subset selection. RESULTS: Fifty-three meshes were analysed. Glenoid inclination (GI) and coronal plane angulation of the acromion (CPAA) [Pearson's r: 0.535; -0.502] correlated best with CSA. The best model (adjusted R-squared value 0.67) for CSA prediction contained 10 explanatory variables including glenoid, scapular spine and acromial factors. CPAA and GI were the most important based on their distribution, estimate of coefficients and loss in predictive power if removed. CONCLUSIONS: The relationship between scapular morphology and CSA is more complex than the concept of it being dictated solely by GI and acromial horizontal offset and includes glenoid, scapular spine and acromial factors of which CPAA and GI are most important. A further investigation in a closely defined cohort with rotator cuff tears is required before drawing any clinical conclusions about the role of surgical modification of scapular morphology. LEVEL OF EVIDENCE: Level 4 retrospective observational cohort study with no comparison group.

The Relationship Between Operative Volume and Peri-operative Mortality After Non-elective Aortic Aneurysm Repair in Australia.

OBJECTIVE: Hospital and surgeon operative caseload is thought to be associated with peri-operative mortality following the non-elective repair of aortic aneurysms; however, whether such an association exists within the Australian healthcare setting is unknown. METHODS: The Australasian Vascular Audit was interrogated to identify patients undergoing non-elective (emergency [EMG] or semi-urgent [URG]) aortic aneurysm repair between 2010 and 2016, as well as their treating surgeon and hospital. Hierarchal logistic regression modelling was used to assess the impact of caseload on outcomes after both endovascular (EVAR) and open surgical repair (OSR). RESULTS: Volume counts were determined from 14 262 patients (4 121 OSR and 10 141 EVAR). After exclusion of elective procedures and duplicates, 1 153 EVAR (570 EMG and 583 URG) and 1 245 OSR (946 EMG and 299 URG) non-elective cases remained for the analysis. Crude mortality was 24.0% following OSR (EMG 29.2%; URG 7.7%) and 7.5% following EVAR (EMG 12.6%; URG 2.4%). Univariable analysis demonstrated an association between OSR mortality and hospital volume (quintile [Q] 1: 25.3%, Q2: 27.8%, Q3: 23.9%, Q4: 27.0%, Q5: 16.2%; p = .030), but not surgeon (Q1: 25.2%, Q2: 27.4%, Q3: 26.0%, Q4: 21.4%, Q5: 19.5%, p = .32). Multivariable analysis confirmed this association (odds ratio (OR) [95% CI]; Q1 vs 5: 1.91 [1.13-3.21], Q2 vs. 5: 2.01[1.24-3.25], Q3 vs. 5: 1.41 [0.86-2.29], Q4 vs. 5: 1.92 [1.17-3.15]; p = .020). The difference was most pronounced in the EMG OSR group [Q1 - 3 vs. 4-5] (OR 1.63 [1.07-2.48]; p = .020). Mortality after EVAR was not associated with either hospital (Q1: 6.3%, Q2: 10%, Q3: 6.8%, Q4: 4.5%, Q5: 10%; p = .14) or surgeon volume (Q1: 9.3%, Q2: 5.7%, Q3: 8.1%, Q4: 7.0%, Q5: 7.3%; p = .67). CONCLUSION: There is an inverse correlation between hospital volume and peri-operative mortality following EMG open repair of aortic aneurysm. These data support restructuring Australian pathways of care to direct suspected ruptured aneurysm to institutions that reach a minimum volume threshold.

The Relationship Between Aortic Aneurysm Surgery Volume and Peri-Operative Mortality in Australia.

OBJECTIVES: Operative caseload is thought to be associated with peri-operative mortality following intact aortic aneurysm repair. The aim was to study that association in the Australian setting, which has a unique healthcare provision system and geographical population distribution. METHODS: The Australasian Vascular Audit database was used to capture volume measurements for both individual surgeon and hospital and to separate it into quintiles (1, lowest, to 5, highest) for endovascular (EVAR), open surgical repair (OSR), and subgroups of repair types between 2010 and 2016. Multivariable logistic regression modelling was used to assess the impact of caseload volumes on in hospital mortality after adjustment for confounders. RESULTS: Volume counts were determined from 14,262 aneurysm repair procedures (4121 OSR, 10,106 EVAR). After exclusions, 2181 OSR (161 complex, 2020 standard) and 7547 EVAR (6198 standard, 1135 complex, 214 thoracic (TEVAR)) elective cases were available for volume analysis. Unadjusted mortality after EVAR was unaffected by either surgeon (Quintile 1, 1.0%; Quintile 5, 0.9%; p = .28) or hospital volume (Quintile 1, 0.8%; Quintile 5, 1.3%; p = .47). However, univariable analysis of the TEVAR subgroup revealed a significant correlation with hospital volume (Quintiles 1-2 vs. Quintiles 3-5; p = .02). Univariable analysis for OSR demonstrated a marginal, non-significant value for surgeon (Quintile 1, 4.0%; Quintile 5, 3.6%; p = .06), but not hospital volume (Quintile 1, 4.7%; Quintile 5, 4.0%; p = .67). After adjustment for confounders hospital volume remained a significant predictor of peri-operative TEVAR mortality (Quintile 1-2 vs. 3-5; OR 5.62, 95% CI 1.27-24.83; p = .02) and surgeon volume a predictor following standard OSR (Quintile 1-2 vs. Quintile 3-5; OR 2.15, 95% CI 1.21-3.83; p = .01). CONCLUSIONS: There is an inverse correlation between both surgeon volume of open aortic aneurysm repair, hospital volume of thoracic endovascular aneurysm repair and in hospital mortality. These findings suggest that in Australia TEVAR should be performed by high volume hospitals and OSR by high volume surgeons.

The Art and Science of Securing an Anaesthesiology Training Job: A Survey of the Key Factors in Two Australian Tertiary Hospitals.

Background There is no specific formal guidance on what prospective trainees must focus on to secure an anaesthetic training position in Australia, and there is little in the literature to advise both applicants and their mentors. Method This study aims to ascertain the views of anaesthetic clinicians from two Australian tertiary referral hospitals on what they consider most important for selection. A paper-based survey was conducted at both hospitals across three groups, totalling 104 participants with a 100% response rate. Results The characteristics most agreed upon to be of at least some importance were clinical anaesthetic knowledge (98%, 102/104), teaching (95%, 99/104), basic science and courses (94%, 98/104), other critical care experience (93%, 97/104), and anaesthetic experience for more than six months (92%, 96/104). Of these, anaesthetic experience of greater than six months, non-anaesthetic critical care experience, and the completion of relevant courses were felt to be most important. Furthermore, good referee reports (95%, 99/104), especially those that come from anaesthetists (75%, 78/104) as well as having previous experience working in the institution applied to (88%, 92/104) were also seen as important factors. 'Non-technical' skills (40%, 42/104) were also regarded as an important factor, with immense competition for a few training positions (45%, 47/104) as the greatest barrier. When it came to selection, prevocational trainees consistently ranked the majority of criteria higher than accredited trainees or specialists. Conclusion This staff survey in two Australian hospitals has shed light on factors considered critical in securing an anaesthetic training position. It underscores the significance of clinical anaesthetic knowledge, basic science proficiency, and relevant critical care experience.

Lateral Acromioplasty With the Aim of Reducing the Critical Shoulder Angle Using Techniques Based on the Lateral Acromial Border Result in Larger-Than-Necessary Resections.

Purpose: To compare the axial plane orientation and width and length of the acromial resections required to reduce the critical shoulder angle (CSA) using lateral acromioplasty (LA) techniques that are based on the lateral acromial border with an ideal resection that is oriented parallel to the glenoid. Methods: This was a retrospective observational cohort study of symptomatic patients that were investigated for shoulder pain, instability, or fracture with high-quality computed tomography (CT). The CT scan data were used to create 3-dimensional meshes, and a series of LA resection planes were mapped. The orientation, width, and length of each resection based on the lateral acromial border (lateral, anterolateral, posterolateral, and image guided) to reduce the measured CSA to 35° or 30° was compared with an ideal resection that was oriented parallel to the glenoid. Results: 23 models had CSA 30.1° to 35°, and 13 had CSA >35°. In the models with CSA >35°, there was no angular difference between the resection planes of the lateral, anterolateral, or image-guided resections compared with the ideal technique; there were differences in the required width and length of the resections to reduce the CSA to 35° (additional width/length: lateral, 3.2/14.8 mm; anterolateral, 2.8/10.6 mm; posterolateral, 6.9/19.2 mm; image guided, 2.4/10.3 mm). Width and length differences were also present in the models with CSA >30° when the resections aimed to reduce the CSA to 30° (additional width/length: lateral, 2.5/12.5 mm; anterolateral, 1.9/8.8 mm; posterolateral, 7.4/19.0 mm; image guided, 1.6/8.8 mm). Conclusions: LA techniques based on the lateral acromial border did not replicate the ideal resection and may lead to excessive deltoid release which could adversely affect clinical results. Clinical relevance: Our findings do not support LA techniques based on the lateral acromial border.

Prognostic Value of Abdominal Aortic Calcification: A Systematic Review and Meta-Analysis of Observational Studies.

Background The prognostic importance of abdominal aortic calcification (AAC) viewed on noninvasive imaging modalities remains uncertain. Methods and Results We searched electronic databases (MEDLINE and Embase) until March 2018. Multiple reviewers identified prospective studies reporting AAC and incident cardiovascular events or all-cause mortality. Two independent reviewers assessed eligibility and risk of bias and extracted data. Summary risk ratios (RRs) were estimated using random-effects models comparing the higher AAC groups combined (any or more advanced AAC) to the lowest reported AAC group. We identified 52 studies (46 cohorts, 36 092 participants); only studies of patients with chronic kidney disease (57%) and the general older-elderly (median, 68 years; range, 60-80 years) populations (26%) had sufficient data to meta-analyze. People with any or more advanced AAC had higher risk of cardiovascular events (RR, 1.83; 95% CI, 1.40-2.39), fatal cardiovascular events (RR, 1.85; 95% CI, 1.44-2.39), and all-cause mortality (RR, 1.98; 95% CI, 1.55-2.53). Patients with chronic kidney disease with any or more advanced AAC had a higher risk of cardiovascular events (RR, 3.47; 95% CI, 2.21-5.45), fatal cardiovascular events (RR, 3.68; 95% CI, 2.32-5.84), and all-cause mortality (RR, 2.40; 95% CI, 1.95-2.97). Conclusions Higher-risk populations, such as the elderly and those with chronic kidney disease with AAC have substantially greater risk of future cardiovascular events and poorer prognosis. Providing information on AAC may help clinicians understand and manage patients' cardiovascular risk better.