Proximal humerus fractures are the third most common fracture type in adults, with their incidence increasing over time. There are varied approaches to both the classification and treatment of proximal humerus fractures. Optimal treatments for this fracture type are still widely open to debate. This review summarizes the current and historical treatment modalities for proximal humerus fractures. In this paper, we provide updates on the advances and trends in the epidemiology, classification, and operative and nonoperative treatments of proximal humerus fractures.

Proximal humeral fractures (PHFs) are a common type of fracture, particularly in older adults, accounting for approximately 5-6% of all fractures. This article provides a comprehensive review of PHFs, focusing on epidemiology, injury mechanism, clinical and radiographic assessment, classification systems, and treatment options. The incidence of PHFs varies across regions, with rates ranging from 45.7 to 60.1 per 100,000 person-years. Females are more susceptible to PHFs than males, and the incidence is highest in women over the age of 85. The injury mechanism of PHFs is typically bimodal, with high-energy injuries predominant in younger individuals and low-energy injuries in the elderly. Clinical assessment of PHFs involves obtaining a thorough history, physical examination, and evaluation of associated injuries, particularly neurovascular injuries. Radiographic imaging helps assess fracture displacement and plan for treatment. The Neer classification system is the most commonly used classification for PHFs, although other systems, such as AO/OTA, Codman-Hertel, and Resch classifications, also exist. The choice of treatment depends on factors such as patient age, activity level, fracture pattern, and surgeon expertise. Nonoperative management is typically preferred for elderly patients with minimal displacement, while operative fixation is considered for more complex fractures. Nonoperative treatment involves sling immobilization followed by physiotherapy, with good outcomes reported for certain fracture patterns. Operative management options include closed reduction and percutaneous pinning (CRPP), open reduction and internal fixation (ORIF), or arthroplasty. CRPP is suitable for specific fracture patterns, but the quality of reduction is crucial for favorable outcomes. ORIF is used when CRPP is not feasible, and various surgical approaches are available, each with its advantages and potential complications. PHFs are a significant clinical challenge due to their prevalence and complexity. Treatment decisions should be patient centered based on patient factors and fracture severity.

Introduction: Quantitative myocardial blood flow (MBF) analysis using stress cardiac magnetic resonance (CMR) has been shown to detect obstructive coronary artery disease (CAD) and coronary microvascular dysfunction (CMD) in several mostly small, single-center studies. The AQUA-MBF ( A ssessment of QUA ntitative MBF ) study is a multicenter initiative involving 16 centers. Hypothesis: The goal of this sub-study is to determine if MBF can differentiate CAD, CMD, and normal volunteers in this multicenter setting. Methods: We present data from 53 subjects (15 with CAD, 20 at risk for CMD and 18 controls) who underwent vasodilator stress CMR (Figure) using 1.5T and 3.0T MR scanners (General Electric). At risk for CMD was defined as having diabetes and 2 other risk factors in absence of ≥50% stenosis based on coronary CT. CAD was defined as the presence of stenosis ≥70% based on invasive coronary angiography. Stress perfusion images were acquired using the dual sequence technique. Stress MBF was measured in each of the 16 AHA segments using Fermi deconvolution (Circle Cvi42). In the CAD group, each segment was further classified as having late gadolinium enhancement (LGE), supplied by CAD, or a normal remote territory. The means of the 5 groups were compared using one-way analysis of variance. Results: The segmental stress MBF (ml/g/min) for the 5 groups are shown in figure. Compared to the normal group, segmental stress MBF in 4 disease groups were significantly lower (p<0.001). Segmental MBF in those at risk for CMD was lower than normal segments and greater than CAD segments (p<0.001). LGE and CAD segments had the lowest stress MBF but similar to each other (p=0.9). Conclusions: In this multicenter study, we show that quantification of MBF using the dual sequence stress perfusion CMR technique can differentiate diseased from healthy myocardium and also between obstructive CAD and those at risk for CMD.

Funding Acknowledgements Type of funding sources: None. Background Phase-sensitive inversion recovery improves tissue contrast by correcting for imperfect choice of inversion recovery time, however it is challenging to combine with a free-breathing acquisition. Deep learning (DL) algorithms have growing applications in cardiac MRI to improve image quality during image reconstruction. Purpose Here, we introduce a single-shot phase-sensitive myocardial delayed enhancement sequence with respiratory triggering (SShPSMDE-RT) (Figure 1). This novel sequence allows faster free-breathing acquisition of late gadolinium enhancement (LGE) images with reduced motion artifact (Figure 2.a). We combined this with a DL noise reduction algorithm to further improve image quality as compared to a standard segmented breath-hold (BH) PSMDE sequence. Methods 61 subjects (29 male, age 51±15) underwent cardiac MRI with the SShPSMDE-RT sequence and a standard BH sequence. The DL algorithm was applied at increasing levels (DL25, DL50, DL75, DL100) (Figure 2.b). Qualitative metrics were image quality, artifact severity, and diagnostic confidence, graded on a 5-point Likert scale. Quantitative metrics were sharpness of the left ventricle septum border and the LGE region (distance in mm for signal intensity to drop from 80% to 20%), blood-myocardium contrast-to-noise ratio (CNR), LGE-myocardium CNR, LGE signal-to-noise ratio (SNR), and LGE burden. 324 slices were included in the analysis. The sequences were compared via paired T-test. Results 27 subjects had positive LGE as determined by CMR experts. The average time to acquire a slice for SShPSMDE-RT is 4–7 seconds versus ∼30–40 seconds for the BH scan. The single-shot sequence had significantly better image quality (SShPSMDE-RT 2.1±0.8 vs. BH 1.5±0.6, p&lt;0.001), less artifact (1.2±0.5 vs. 2.6±1.1, p&lt;0.001), and better diagnostic confidence (3.4±0.7 vs. 2.6±0.8, p&lt;0.001). Septum sharpness was slightly worse in SShPSMDE-RT images (4.1±1.7 mm vs. 3.8±1.6 mm, p = 0.008), but the DL algorithm improved sharpness of SShPSMDE-RT images such that there was no significant difference compared to BH images (p&gt;0.5). There was no significant difference in LGE sharpness between the sequences. The SShPSMDE-RT images had superior blood-myocardium CNR (17.2±6.9 vs. 16.4±6.0, p = 0.040), LGE-myocardium CNR (12.1±7.2 vs. 10.4±6.6, p = 0.054), and LGE SNR (59.8±26.8 vs. 31.2±24.1, p&lt;0.001); these metrics all improved with application of the DL algorithm. There was no significant difference in measured LGE burden (p = 0.12). Conclusions Our novel SShPSMDE-RT sequence significantly reduces scan time and motion artifact. This free-breathing sequence combined with a DL noise reduction algorithm provides better or similar image quality on both qualitative and quantitative metrics as compared to a standard BH PSMDE sequence. This technique can be used to obtain LGE imaging in patients who are unable to breath-hold or tolerate longer scan times.