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The execution technique of hanging, introduced by the Angle, Saxon, and Jute Germanic tribes during their invasions of the Roman Empire and Britain in the 5th century, has remained largely unchanged over time. The earliest form of a gallows was a tree on which prisoners were hanged. Despite the introduction of several modifications such as a trap door, the main mechanism of death remained asphyxiation. This created the opportunity for attempted revival after the execution, and indeed several well-known cases of survival following judicial hanging have been reported. It was not until the introduction of the standard drop by Dr. Samuel Haughton in 1866, and the so-called long drop by William Marwood in 1872 that hanging became a standard, humane means to achieve instantaneous death. Hangmen, however, fearing knot slippage, started substituting the subaural knot for the traditional submental knot. Subaural knots were not as effective, and cases of decapitation were recorded. Standardization of the long drop was further propagated by John Berry, an executioner who used mathematical calculations to estimate the correct drop length for each individual to be hanged. A British committee on capital sentences, led by Lord Aberdare, studied the execution method, and advocated for the submental knot. However, it was not until Frederic Wood-Jones published his seminal work in 1913 that cervical fractures were identified as the main mechanism of death following hanging in which the long drop and a submental knot were used. Schneider introduced the term "hangman's fracture" in 1965, and reported on the biomechanics and other similarities of the cervical fractures seen following judicial hangings and those caused by motor vehicle accidents.

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Seven millennia of anthropological artifacts and historical tales reference human spinal deformity, its diagnosis, and treatment-many of the latter of which turned out to be worse than the deformity itself. From Hippocrates to Harrington to the 21st century, the literature base has expanded in exponential fashion to yield an imperfect but constantly improving body of evidence, experience, and understanding of this challenging disease phenomenon. This review details the pre-1990 innovations, whose failures and successes have equally contributed to the advancement and dissemination of the increasingly evidence-based field of spinal deformity.

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Medical historians generally consider anatomic science, as we know it today, to have been established through the pioneering work of Vesalius during the Renaissance. Although this is largely true, detailed assessment of the scientific advances made in the late Middle Ages, though not as spectacular as those made during the Renaissance period, did pave the way and form a foundation for subsequent progress. During the two centuries of AD 1300 to 1500, several worthwhile advances occurred. Many universities, centers of learning excellence, were established throughout Europe, most notably in Italy. King Frederick II, the Holy Roman Emperor, established guidelines for medical education and practice that seem to parallel current regulations. Human cadaveric dissection was performed, after a hiatus of over 1700 years, as the foundation for the study of anatomy. Observation of human dissection became a requirement for medical students. A manual for anatomic dissection was written, printed, and published for the first time in history by Mondino de Liuzzi. His student, Guido da Vigevano, who also had an engineering background, established two "firsts" of his own: providing illustrations of anatomy and designing the first automobile in history. The authors believe that the contributions of these two key anatomists in the late Middle Ages should not be forgotten.

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The artery of Adamkiewicz is an important radiculomedullary artery supplying the spinal cord, especially the lumbar enlargement. Anatomical knowledge of this artery is important for avoiding serious neurological complications during surgery performed in this region--for neurosurgeons and interventional radiologists treating intramedullary tumors and spinal arteriovenous malformations, traumatologists performing spinal fusions, thoracic surgeons treating aortic aneurysms, and urologists and pediatric surgeons conducting retroperitoneal dissections. However, the biography of the talented Polish pathologist Albert Adamkiewicz, after whom the landmark artery is named, has not been described adequately in the existing neurosurgical literature. The authors bring to light the historical perspective of the eponymic artery and provide a recapitulation of other significant contributions made by Adamkiewicz, mostly involving the nervous system. His research papers on the histology of neuronal tissues and neurodegenerative diseases had high scientific merit, but the discovery of the anticancer antitoxin "cancroin" and his postulation of a cancer-causing parasite he named "Coccidium sarcolytus" met with harsh criticism and eventually led to his ill fame. The biography is supplemented with a brief overview of the important surgical implications of the artery of Adamkiewicz.

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From prehistoric times, man has been aware that injury to the spine may result in paralysis of the limbs; this is reflected in bas-relief figures found at Nineweh in ancient Mesopotamia, in a hunting scene that depicts a lioness wounded by King Ashurbanipal. The Edwin Smith papyrus gives many case illustrations of spinal cord injury resulting in paralysis, yet early physicians were unaware of the anatomy of the spinal cord. Galen performed prospective studies in animals by sectioning the spinal cord at varying levels and observing the commensurate paralysis and sensory loss. Real advances in the understanding of spinal cord anatomy did not occur until human cadaveric dissections were undertaken; even then, the knowledge of the anatomy of the spinal cord lagged behind that of other body structures. Johann Jacob Huber appears to be the first anatomist to focus on the spinal cord almost exclusively. His descriptions, and especially his illustrations that depict spinal cord surface anatomy, are impressive with regard to their accuracy and their sense of photorealism. Indeed, his illustrations seem to compare well with the anatomic drawings in contemporary anatomic texts. Yet, we were unable to find a single article in the entire English-language literature depicting his illustrations. We conclude that the description and anatomic illustrations by Johann Jacob Huber remain a hidden gem in the history of human spinal anatomy.

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Thomas Willis established neurology as a distinct discipline and made significant original contributions to many related fields including anatomy, pathology, cardiology, endocrinology, and gastroenterology. He is most remembered for his work in elucidating the function and anatomy of the circle of Willis. Willis' accomplishments and research methods can be credited in large part to his unconventional medical education which did not include traditional teachings, but rather emphasized learning through clinical practice. Although Willis was not the first to describe the arterial circle, he was the first to describe its function and provide a complete, undisputed illustration through his own innovative use of dye studies. The Willis classification of cranial nerves was still in use over 100 years after its original description. He has also described several disease entities and named many brain structures. Willis' accomplishments in comparative anatomy and understanding the pathophysiology of various diseases through original multidisciplinary experimental work in a clinical setting reveal that he was a true pioneer in translational research.

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The discovery of the Bell-Magendie Law, which states that the ventral spinal roots transmit motor impulses and the posterior roots sensory impulses, established a major landmark in the history of neuroscience. It led to further elucidation of brain function and served as a starting point for virtually all of electrophysiology. During the past two centuries, there has been an intense debate as to which of the two scientists deserves the credit for the discovery itself and the prominent claim to the discovery. Extensive literature exists in this regard, and the goal of the authors is not to dwell on it further but rather to summarize the arguments. The major objective of this work, however, is to elaborate on the two medicosocial issues that were brought into focus by the discovery of the Bell-Magendie Law, namely, the provision of adequate numbers of cadavers for the sound anatomic education of medical students, so that the despicable practice of "body-snatching" could be abolished, and the prevention of cruelty to the experimental animals used for biomedical research. Public opinion prevailing at the time of the postulation of the Bell-Magendie Law promoted the establishment of the Royal Society for the Prevention of Cruelty to Animals, and other similar societies were established worldwide. The authors summarize the current status of these two issues.

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Brown-Sequard is known eponymously for the syndrome of hemisection of the spinal cord, but most clinicians are not familiar with his colorful, quixotic, and eccentric life history. His contributions to medicine and neuroscience reached much further than his discovery of the spinal hemisection syndrome. He lived in five countries on three continents and crossed the Atlantic 60 times, spending a total of almost 6 years on the sea. He contributed more than 500 papers in his lifetime, was even the editor of many prestigious journals, and spent his last years as Professeur au Collége de France, a most coveted position for a French neuroscientist. Many are not aware of his contributions to endocrinology and hormone replacement therapy, even those who consider him the father of modern endocrinology. Brown-Séquard was a skillful experimentalist. He pioneered the concept of the advancement of neuroscience through experimental physiological observation. He was devoted to science. He was not interested in monetary gains through his inventions or patient care. Although he may be criticized for arriving at some incorrect conclusions from his experiments, his visionary ideas and prescient statements have stood the test of time; he truly was an eccentric genius. This article highlights Brown-Séquard's life history, specifically his time in France and North America, and his contributions to neuroscience and endocrinology.

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Sir Robert Boyle is one of the foremost English scientists in history. He received his inspiration from the scientific approaches initiated by Galileo and his disciple, Torricelli. Through rigorous experimentation, Boyle established the fundamental gas laws as we know them today. Although not a physician himself, he contributed enormously to the practice of medical sciences. His voluminous observations and writings represent a landmark in the history of human thought. This article summarizes the scientific contributions of Robert Boyle, with particular emphasis on his contributions to medicine. Boyle wrote a unique case report describing in detail a patient with depressed cranial fracture who underwent successful surgery. Although on only a single case report, it provides us with a unique and rare opportunity to look at the practice of neurosurgery in the mid-17th century. Also presented in this article is Boyle's accurate description of a horse with holoprosencephaly, which was perhaps the first in history. The oft-quoted axiom in clinical medicine "First, do no harm (primum non nocere)" attributed to Sydenham, may be partially credited to Robert Boyle as well.

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OBJECTIVE: To compare the biomechanical stability imparted to the C1 and C2 vertebrae by either transarticular screw fixation (TSF) or screw and rod fixation (SRF) techniques in a cadaver model. METHODS: Ten fresh ligamentous human cervical spine specimens were harvested from cadavers. The specimens were tested sequentially in the intact state, after injury and stabilization (unilateral left side and bilateral), and after fatiguing to 5000 cycles (0.5 Hz) at +/-1.0 N.m of flexion and extension. The specimens were stabilized by use of TSF in 5 spines or SRF in the other 5 spines. The data were converted to angular displacements, and the stabilized cases were compared with intact states for evaluating the efficacies of the two techniques in stabilizing the C1-C2 segments. RESULTS: In the TSF group, the unilateral fixation using one screw imparted a significant stability in only the axial rotation mode. The unilateral procedure in the SRF group was effective in stabilization in all modes except in extension. The bilateral procedure in both of the groups was effective across the C1-C2 segment. However, the SRF group afforded higher stability than the corresponding TSF group in the flexion and extension modes. The degree of stability did not change after fatigue compared with the prefatigue data. CONCLUSION: In general, a surgeon should undertake a bilateral fixation to achieve sufficient stability across the atlantoaxial complex, and either technique will provide satisfactory results, although the SRF technique may be better in the flexion and extension modes. One should use the SRF procedure while trying to achieve stability with a unilateral system.

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Internal disc disruption associated with axial back pain but not radicular pain is a disease entity that was recognized about two decades ago as a disorder that could potentially be treated by spinal fusion. In this article the authors describe the clinical syndrome, magnetic resonance imaging and discography findings of pathophysiological pain generation, and the available surgical options. Based on the current understanding of this disease entity, the optimum surgical procedure entails radical discectomy, anterior column support, adequate amounts of auto- or allograft bone, bone extenders and enhancers, and rigid stabilization of the motion segment.

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In this article the authors discuss the syndrome of isthmic spondylolisthesis occurring at the lumbosacral junction in adults, providing a description of the clinical syndrome, altered biomechanics, and imaging characteristics. The authors pose arguments in favor of reduction and instrument-assisted fusion. Their surgical technique is detailed. They describe transsacral interbody fusion in which fibular allograft and in situ fixation are used, which they consider the second-best alternative technique when attempts at reduction fail.

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Bone is a tissue that constantly undergoes deposition, resorption of stromal matrix, and remodeling. These processes may be altered by a variety of chemical, mechanical, cellular, and pathological mechanisms. Understanding the physiology of bone healing and the mechanisms affecting this process is important not only when evaluating normal skeletal development but also when initiating fracture repair. Because the ultimate success of spinal fusions involves creation of an osseous union, we focus this review on the anatomy and physiology of bone under physiological conditions, normal bone healing and mechanisms that alter it, and available adjuvant therapies that may enhance healing potential in a clinical setting.

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The cellular and molecular events governing bone formation in the embryo, healing of a fractured bone, and induced bone fusion follow a similar pattern. Discovery, purification, and recombinant synthesis of bone morphogenetic proteins (BMPs) constitute a major milestone in the understanding of bone physiology. In this review the author discusses the mechanism of action, clinical applications, dosage, and optimum carriers for BMPs. The roles played by other growth factors are also discussed.

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