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Neurosurgery Clinics of North America Jan 2020Adult spinal deformity is a major contributor to pain and disability. It is a degenerative disease with a rigid spine. Spinopelvic parameters have been identified that... (Review)
Review
Adult spinal deformity is a major contributor to pain and disability. It is a degenerative disease with a rigid spine. Spinopelvic parameters have been identified that outline goals of operative intervention, as they have shown to significantly improve patient outcomes. Previously, this was accomplished with large, open fusions. Unfortunately, the adult spinal deformity population is often elderly with significant comorbidities. These extensive fusions have a high rate of morbidity and mortality. Technological advances have allowed minimally invasive approaches to be developed. These techniques have decreased operative morbidity without increasing health care spending.
Topics: Humans; Lordosis; Minimally Invasive Surgical Procedures; Neurosurgical Procedures; Pelvis; Scoliosis; Spine
PubMed: 31739921
DOI: 10.1016/j.nec.2019.08.013 -
American Journal of Obstetrics and... Mar 2024It seems puzzling why humans have evolved such a small and rigid birth canal that entails a relatively complex process of labor compared with the birth canal of our... (Review)
Review
It seems puzzling why humans have evolved such a small and rigid birth canal that entails a relatively complex process of labor compared with the birth canal of our closest relatives, the great apes. This study reviewed insights into the evolution of the human birth canal from recent theoretical and empirical studies and discussed connections to obstetrics, gynecology, and orthopedics. Originating from the evolution of bipedality and the large human brain million years ago, the evolution of the human birth canal has been characterized by complex trade-off dynamics among multiple biological, environmental, and sociocultural factors. The long-held notion that a wider pelvis has not evolved because it would be disadvantageous for bipedal locomotion has not yet been empirically verified. However, recent clinical and biomechanical studies suggest that a larger birth canal would compromise pelvic floor stability and increase the risk of incontinence and pelvic organ prolapse. Several mammals have neonates that are equally large or even larger than human neonates compared to the size of the maternal birth canal. In these species, the pubic symphysis opens widely to allow successful delivery. Biomechanical and developmental constraints imposed by bipedality have hindered this evolutionary solution in humans and led to the comparatively rigid pelvic girdle in pregnant women. Mathematical models have shown why the evolutionary compromise to these antagonistic selective factors inevitably involves a certain rate of fetopelvic disproportion. In addition, these models predict that cesarean deliveries have disrupted the evolutionary equilibrium and led to new and ongoing evolutionary changes. Different forms of assisted birth have existed since the stone age and have become an integral part of human reproduction. Paradoxically, by buffering selection, they may also have hindered the evolution of a larger birth canal. Many of the biological, environmental, and sociocultural factors that have influenced the evolution of the human birth canal vary globally and are subject to ongoing transitions. These differences may have contributed to the global variation in the form of the birth canal and the difficulty of labor, and they likely continue to change human reproductive anatomy.
Topics: Animals; Infant, Newborn; Humans; Pregnancy; Female; Biological Evolution; Hominidae; Pelvis; Cesarean Section; Labor, Obstetric; Pelvic Floor; Mammals
PubMed: 38462258
DOI: 10.1016/j.ajog.2022.09.010 -
Radiographics : a Review Publication of... Oct 2022US and MRI-guided therapeutic US (TUS) can aid in the treatment of prostate, liver, and pancreatic cancer, as well as uterine fibroids and osseous metastases, and...
US and MRI-guided therapeutic US (TUS) can aid in the treatment of prostate, liver, and pancreatic cancer, as well as uterine fibroids and osseous metastases, and understanding the selection and optimization of treatment strategies is essential to furthering TUS advances and innovations.
Topics: Abdomen; Abdominal Cavity; Humans; Pelvis
PubMed: 36190852
DOI: 10.1148/rg.220044 -
The Journal of Emergency Medicine Aug 2019
Topics: Accidental Falls; Adult; Alcohol Drinking; Chest Tubes; Emergency Service, Hospital; Gynecological Examination; Hemorrhage; Humans; Male; Obesity; Pelvis; Pneumothorax; Radiography; Wounds, Nonpenetrating
PubMed: 31164234
DOI: 10.1016/j.jemermed.2019.04.002 -
Military Medicine Nov 2023Combat-related injuries from improvised explosive devices occur commonly to the lower extremity and spine. As the underbody blast impact loading traverses from the seat...
INTRODUCTION
Combat-related injuries from improvised explosive devices occur commonly to the lower extremity and spine. As the underbody blast impact loading traverses from the seat to pelvis to spine, energy transfer occurs through deformations of the combined pelvis-sacrum-lumbar spine complex, and the time factor plays a role in injury to any of these components. Previous studies have largely ignored the role of the time variable in injuries, injury mechanisms, and warfighter tolerance. The objective of this study is to relate the time or temporal factor using a multi-component, pelvis-sacrum-lumbar spinal column complex model.
MATERIALS AND METHODS
Intact pelvis-sacrum-spine specimens from pre-screened unembalmed human cadavers were prepared by fixing at the superior end of the lumbar spine, pelvis and abdominal contents were simulated, and a weight was added to the cranial end of the fixation to account for torso effective mass. Prepared specimens were placed on the platform of a custom vertical accelerator device and aligned in a seated soldier posture. An accelerometer was attached to the seat platen of the device to record the time duration to peak velocity. Radiographs and computed tomography images were used to document and associate injuries with time duration.
RESULTS
The mean age, stature, weight, body mass index, and bone density of 12 male specimens were as follows: 65 ± 11 years, 1.8 ± 0.01 m, 83 ± 13 kg, 27 ± 5.0 kg/m2, and 114 ± 21 mg/cc. They were equally divided into short, medium, and long time durations: 4.8 ± 0.5, 16.3 ± 7.3, and 34.5 ± 7.5 ms. Most severe injuries associated with the short time duration were to pelvis, although they were to spine for the long time duration.
CONCLUSIONS
With adequate time for the underbody blast loading to traverse the pelvis-sacrum-spine complex, distal structures are spared while proximal/spine structures sustain severe/unstable injuries. The time factor may have implications in seat and/or seat structure design in future military vehicles to advance warfighter safety.
Topics: Humans; Male; Middle Aged; Aged; Sacrum; Spinal Injuries; Explosions; Pelvis; Lumbar Vertebrae; Cadaver; Blast Injuries; Biomechanical Phenomena
PubMed: 37948210
DOI: 10.1093/milmed/usad168 -
The Journal of the American Academy of... Sep 2022Traumatic hemipelvectomy (THP) is a catastrophic injury associated with high-energy trauma and high mortality. THP has been defined as a complete dislocation of the...
Traumatic hemipelvectomy (THP) is a catastrophic injury associated with high-energy trauma and high mortality. THP has been defined as a complete dislocation of the hemipelvis, often with disruption through the symphysis pubis and sacroiliac joint with concurrent traumatic rupture of the iliac vessels. Despite recent advances in prehospital resuscitative techniques, the true incidence of THP is difficult to ascertain because many patients die before hospital arrival. The leading causes of death associated with THP include blood loss, infection, and multiple system organ failure. Recognition and immediate intervention for these injuries is imperative for survival. The initial assessment includes a thorough physical examination assessing for signs of arterial damage and other associated injuries. Hemorrhage control and vigorous resuscitation should be prioritized to combat impending exsanguination. Emergent amputation has been found to be a lifesaving operation in these patients. The basis of this approach is rooted in achieving complete hemostasis while reducing complication rates. Understanding the nature of these massive pelvic injuries, the role of early amputation, and the importance of subspecialty communication can improve survivability and optimize patient outcomes.
Topics: Amputation, Surgical; Hemipelvectomy; Hemorrhage; Humans; Joint Dislocations; Pelvis; Sacroiliac Joint
PubMed: 36166384
DOI: 10.5435/JAAOS-D-21-01018 -
Medical Physics Apr 2022Diffusion MRI has enormous potential and utility in the evaluation of various abdominal and pelvic disease processes including cancer and noncancer imaging of the liver,...
Diffusion MRI has enormous potential and utility in the evaluation of various abdominal and pelvic disease processes including cancer and noncancer imaging of the liver, prostate, and other organs. Quantitative diffusion MRI is based on acquisitions with multiple diffusion encodings followed by quantitative mapping of diffusion parameters that are sensitive to tissue microstructure. Compared to qualitative diffusion-weighted MRI, quantitative diffusion MRI can improve standardization of tissue characterization as needed for disease detection, staging, and treatment monitoring. However, similar to many other quantitative MRI methods, diffusion MRI faces multiple challenges including acquisition artifacts, signal modeling limitations, and biological variability. In abdominal and pelvic diffusion MRI, technical acquisition challenges include physiologic motion (respiratory, peristaltic, and pulsatile), image distortions, and low signal-to-noise ratio. If unaddressed, these challenges lead to poor technical performance (bias and precision) and clinical outcomes of quantitative diffusion MRI. Emerging and novel technical developments seek to address these challenges and may enable reliable quantitative diffusion MRI of the abdomen and pelvis. Through systematic validation in phantoms, volunteers, and patients, including multicenter studies to assess reproducibility, these emerging techniques may finally demonstrate the potential of quantitative diffusion MRI for abdominal and pelvic imaging applications.
Topics: Abdomen; Artifacts; Diffusion Magnetic Resonance Imaging; Humans; Male; Pelvis; Reproducibility of Results
PubMed: 34554579
DOI: 10.1002/mp.15246 -
Radiographics : a Review Publication of... 2022The pelvic venous system is complex, with the potential for numerous pathways of collateralization. Owing to stenosis or occlusion, both thrombotic and nonthrombotic... (Review)
Review
The pelvic venous system is complex, with the potential for numerous pathways of collateralization. Owing to stenosis or occlusion, both thrombotic and nonthrombotic entities in the pelvis may necessitate alternate routes of venous return. Although the pelvic venous anatomy and collateral pathways may demonstrate structural variability, a number of predictable paths often can be demonstrated on the basis of the given disease and the level of obstruction. Several general categories of collateral pathways have been described. These pathway categories include the deep pathway, which is composed of the lumbar and sacral veins and vertebral venous plexuses; the superficial pathway, which is composed of the circumflex and epigastric vessels; various iliofemoral collateral pathways; the intermediate pathway, which is composed of the gonadal veins and the ovarian and uterine plexuses; and portosystemic pathways. The pelvic venous anatomy has been described in detail in cadaveric and anatomic studies, with the aforementioned collateral pathways depicted on CT and MR images in several imaging studies. A comprehensive review of the native pelvic venous anatomy and collateralized pelvic venous anatomy based on angiographic features has yet to be provided. Knowledge of the diseases involving a number of specific pelvic veins is of clinical importance to interventional and diagnostic radiologists and surgeons. The ability to accurately identify common collateral patterns by using multiple imaging modalities, with accurate anatomic descriptions, may assist in delineating underlying obstructive hemodynamics and diagnosing specific occlusive disease entities. RSNA, 2022.
Topics: Abdomen; Collateral Circulation; Humans; Pelvis; Phlebography; Vascular Diseases; Veins
PubMed: 35867595
DOI: 10.1148/rg.220012 -
Radiation Protection Dosimetry Feb 2024Projection radiography is the most common radiological modality, and radiation safety of it concerns both radiation workers and the public. We measured and generated a...
Projection radiography is the most common radiological modality, and radiation safety of it concerns both radiation workers and the public. We measured and generated a series of scattered radiation maps for projection radiography and estimated effective doses of the supporting person during exposure. Measured adult patient protocols included chest posterior-anterior, chest lateral, pelvis anterior-posterior (AP), abdomen AP and bedside chest AP. Maps concretise spatial distribution and the scattered radiation dose rates in different imaging protocols. Highest and lowest rates were measured in abdomen AP and bedside chest AP protocols, respectively. The effective dose of supporting person in abdomen AP examination at distance of 0.5 m was 300 nSv and in bedside supine chest AP examination at distance of 0.7 m was 0.5 nSv. The estimated annual effective dose of emergency unit radiographer was 0.11 mSv. The obtained effective dose values are small compared to annual dose limits of radiation workers and the public.
Topics: Adult; Humans; X-Rays; Radiation Dosage; Radiography; Pelvis; Physical Examination; Radiography, Thoracic
PubMed: 37939724
DOI: 10.1093/rpd/ncad275 -
American Journal of Physical... Sep 2020Obstetric demands have long been considered in the evolution of the pelvis, yet consideration of the interaction of pregnancy, the pelvis, and the gastrointestinal tract...
OBJECTIVES
Obstetric demands have long been considered in the evolution of the pelvis, yet consideration of the interaction of pregnancy, the pelvis, and the gastrointestinal tract (gut) is lacking. Here, we explore sex differences in the relationship of gut volume with body size and pelvic dimensions.
MATERIALS AND METHODS
Computed tomography (CT) scans of living adult Homo sapiens (46 females and 42 males) were obtained to measure in vivo gut volume (GV) and to extract 3D models of the pelvis. We collected 19 3D landmarks from each pelvis model to acquire pelvic measurements. We used ordinary least squares regression to explore relationships between GV and body weight, stature, and linear pelvic dimensions.
RESULTS
The gut-pelvis relationship differs between males and females. Females do not exhibit significant statistical correlations between GV and any variable tested. GV correlates with body size and pelvic outlet size in males. GV scales with negative allometry relative to body weight, stature, maximum bi-iliac breadth, inferior transverse outlet breadth, and bispinous distance in males.
DISCUSSION
The lack of association between GV and body size in females may be due to limits imposed by the anticipation of accommodating a gravid uterus and/or the increased plasticity of the pelvis. The pattern of relationship between GV and the pelvic outlet suggests the role of the bony pelvis in supporting the adominal viscera in females may be small relative to its role in childbirth. We conclude that gut size inference in fossil hominins from skeletal proxies is limited and confounded by sexual dimorphism.
Topics: Adult; Anatomic Landmarks; Anthropology, Physical; Anthropometry; Female; Gastrointestinal Tract; Humans; Male; Pelvis; Pregnancy; Sex Characteristics
PubMed: 32519366
DOI: 10.1002/ajpa.24084