Pelvic radiograph (PXR) is essential for detecting proximal femur and pelvis injuries in trauma patients, which is also the key component for trauma survey. None of the currently available algorithms ...can accurately detect all kinds of trauma-related radiographic findings on PXRs. Here, we show a universal algorithm can detect most types of trauma-related radiographic findings on PXRs. We develop a multiscale deep learning algorithm called PelviXNet trained with 5204 PXRs with weakly supervised point annotation. PelviXNet yields an area under the receiver operating characteristic curve (AUROC) of 0.973 (95% CI, 0.960-0.983) and an area under the precision-recall curve (AUPRC) of 0.963 (95% CI, 0.948-0.974) in the clinical population test set of 1888 PXRs. The accuracy, sensitivity, and specificity at the cutoff value are 0.924 (95% CI, 0.912-0.936), 0.908 (95% CI, 0.885-0.908), and 0.932 (95% CI, 0.919-0.946), respectively. PelviXNet demonstrates comparable performance with radiologists and orthopedics in detecting pelvic and hip fractures.
Introduction
Standing in an erect position is a human property. The pelvis anatomy and position, defined by the pelvis incidence, interact with the spinal organization in shape and position to ...regulate the sagittal balance between both the spine and pelvis. Sagittal balance of the human body may be defined by a setting of different parameters such as (a) pelvic parameters: pelvic incidence (PI), pelvic tilt (PT) and sacral slope (SS); (b) C7 positioning: spino-pelvic angle (SSA) and C7 plumb line; (c) shape of the spine: lumbar lordosis.
Biomechanical adaptation of the spine in pathology
In case of pathological kyphosis, different mechanical compensations may be activated. When the spine remains flexible, the hyperextension of the spine below or above compensates the kyphosis. When the spine is rigid, the only way is rotating backward the pelvis (retroversion). This mechanism is limited by the value of PI. Hip extension is a limitation factor of big retroversion when PI is high. Flexion of the knees may occur when hip extension is overpassed. The quantity of global kyphosis may be calculated by the SSA. The more SSA decreases, the more the severity of kyphosis increases. We used Roussouly’s classification of lumbar lordosis into four types to define the shape of the spine. The forces acting on a spinal unit are combined in a contact force (CF). CF is the addition of gravity and muscle forces. In case of unbalance, CF is tremendously increased. Distribution of CF depends on the vertebral plate orientation. In an average tilt (45°), the two resultants, parallel to the plate (sliding force) or perpendicular (pressure), are equivalent. If the tilt increases, the sliding force is predominant. On the contrary, with a horizontal plate, the pressure increases. Importance of curvature is another factor of CF distribution. In a flat or kyphosis spine, CF acts more on the vertebral bodies and disc. In the case of important extension curvature, it is on the posterior elements that CF acts more. According to the shape of the spine, we may expect different degenerative evolution: (a) Type 1 is a long thoraco-lumbar kyphosis and a short hyperlordosis: discopathies in the TL area and arthritis of the posterior facets in the distal lumbar spine. In younger patients, L4 S1 hyperextension may induce a nutcracker L5 spondylolysis. (b) Type 2 is a flat lordosis: Stress is at its maximum on the discs with a high risk of early disc herniation than later with multilevel discopathies. (c) Type 3 has an average shape without characteristics for a specific degeneration of the spine. (d) Type 4 is a long and curved lumbar spine: this is the spine for L5 isthmic lysis by shear forces. When the patient keeps the lordosis curvature, a posterior arthritis may occur and later a degenerative L4 L5 spondylolisthesis. Older patients may lose the lordosis curvature, SSA decreases and pelvis tilt increases. A widely retroverted pelvis with a high pelvic incidence is certainly a previous Type 4 and a restoration of a big lordosis is needed in case of arthrodesis.
Conclusion
The genuine shape of the spine is probably one of the main mechanical factors of degenerative evolution. This shape is oriented by a shape pelvis parameter, the pelvis incidence. In case of pathology, this constant parameter is the only signature to determine the original spine shape we have to restore the balance of the patient.
Introduction
Aging spine is characterized by facet joints arthritis, degenerative disc disease, bone remodeling and atrophy of extensor muscles resulting in a progressive kyphosis of the lumbar ...spine.
Objective
The aim of this paper is to describe the different compensatory mechanisms for patients with severe degenerative lumbar spine.
Material and methods
According to the severity of the imbalance, three stages are observed: balanced, balanced with compensatory mechanisms and imbalanced. For the two last stages, the compensatory mechanisms permit to limit the consequences of loss of lumbar lordosis on global sagittal alignment and therefore contribute to keep the sagittal balance of the spine.
Results
The basic concept is to extend adjacent segments of the kyphotic spine allowing for compensation of the sagittal unbalance but potentially inducing adverse effects.
Conclusion
Finally, we propose a three-step algorithm to analyze the global balance status and take into consideration the presence of the compensatory mechanisms in the spinal, pelvic and lower limb areas.
Purpose
Upper-tract urothelial carcinoma (UTUC) is a relatively uncommon disease with limited available evidence on specific topics. The purpose of this article was to review the previous literature ...to summarize the current knowledge about UTUC epidemiology, diagnosis, preoperative evaluation and prognostic assessment.
Methods
Using MEDLINE, a non-systematic review was performed including articles between January 2000 and February 2016. English language original articles, reviews and editorials were selected based on their clinical relevance.
Results
UTUC accounts for 5–10 % of all urothelial cancers, with an increasing incidence. UTUC and bladder cancer share some common risk factors, even if they are two different entities regarding practical, biological and clinical characteristics. Aristolochic acid plays an important role in UTUC pathogenesis in certain regions. It is further estimated that approximately 10 % of UTUC are part of the hereditary non-polyposis colorectal cancer spectrum disease. UTUC diagnosis remains mainly based on imaging and endoscopy, but development of new technologies is rapidly changing the diagnosis algorithm. To help the decision-making process regarding surgical treatment, extent of lymphadenectomy and selection of neoadjuvant systemic therapies, predictive tools based on preoperative patient and tumor characteristics have been developed.
Conclusions
Awareness regarding epidemiology, diagnosis, preoperative evaluation and prognostic assessment changes is essential to correctly diagnose and manage UTUC patients, thereby potentially improving their outcomes.
•Penetrating trauma covers gunshot wounds and stab and puncture wounds.•Firearm related injuries make up the bulk of the mortality in penetrating trauma.•Nonoperative management acceptable in select ...patients.•CT is accurate in predicting the need for laparotomy in penetrating abdominal trauma.•Specific CT findings can indicate need for laparotomy or endovascular therapy.
Penetrating abdominal trauma comprises a wide variety of injuries that will manifest themselves at imaging depending on the distinct mechanism of injury. The use of computed tomography (CT) for hemodynamically stable victims of penetrating torso trauma continues to increase in clinical practice allowing more patients to undergo initial selective non-surgical management. High diagnostic accuracy in this setting helps patients avoid unnecessary surgical intervention and ultimately reduce morbidity, mortality and associated medical costs. This review will present the evidence and the controversies surrounding the imaging of patients with penetrating abdominopelvic injuries. Available protocols, current MDCT technique controversies, organ-specific injuries, and key MDCT findings requiring intervention in patients with penetrating abdominal and pelvic trauma are presented. In the hemodynamically stable patient, the radiologist will play a key role in the triage of these patients to operative or nonoperative management.
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