Academic literature on the topic 'Proximal-SO'
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Journal articles on the topic "Proximal-SO"
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Haque, S. K., G. Ariceta, and D. Batlle. "Proximal renal tubular acidosis: a not so rare disorder of multiple etiologies." Nephrology Dialysis Transplantation 27, no. 12 (December 1, 2012): 4273–87. http://dx.doi.org/10.1093/ndt/gfs493.
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HERZBERG, G., D. FORISSIER, and C. FALAISE. "Coronal Fractures of the Proximal Scaphoid: The Proximal Ring Sign." Journal of Hand Surgery 28, no. 5 (October 2003): 500–501. http://dx.doi.org/10.1016/s0266-7681(03)00145-1.
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We present two coronal fractures of the proximal scaphoid which were both missed in the acute stage as interpretation of initial radiographs was difficult. In both cases, recognition of the so-called “Proximal Ring Sign” on the PA ulnar deviation radiographs may have helped diagnosis. CT scans were necessary to fully demonstrate the fractures. Open reduction and internal fixation, performed 2 and 4 months after the injury, resulted in union in both cases.
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Yokote, Akira, Kousuke Fukuhara, Jun Tsugawa, and Yoshio Tsuboi. "Juvenile Muscular Atrophy of the Proximal Upper Extremity as So-Called Proximal-Type Hirayama Disease: Case Report and Review of the Literature." Case Reports in Neurology 11, no. 1 (March 21, 2019): 106–11. http://dx.doi.org/10.1159/000495606.
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Hirayama disease is a distinct type of cervical myelopathy characterized by juvenile onset of unilateral muscular atrophy of a distal upper extremity. We report herein a case with Hirayama disease-like juvenile muscular atrophy involving proximal muscles in the upper extremities. In this case, in the flexion position of the neck, cervical magnetic resonance imaging revealed that the spinal cord was compressed by expansion of the posterior extradural space with forward displacement of the dura matter. These neuroimaging results are identical to those of Hirayama disease. However, the involved muscles in this case were the proximal muscles, unlike Hirayama disease. Five previous cases have displayed this rare subtype of Hirayama disease. The cause of the unique phenotype may be abnormal cervical column alignment, with upper cervical kyphosis producing a higher apex of the vertebral level in a cervical flexion position, resulting in mid-cervical segmental myelopathy.
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Suzuki, T., W. J. Dodds, S. K. Sarna, W. J. Hogan, R. A. Komorowski, and Z. Itoh. "Control mechanisms of sphincter of Oddi contraction rate in the opossum." American Journal of Physiology-Gastrointestinal and Liver Physiology 255, no. 5 (November 1, 1988): G619—G626. http://dx.doi.org/10.1152/ajpgi.1988.255.5.g619.
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Our aim in this study is to determine whether extrinsic autonomic nerves regulated spike-burst rate in the opossum sphincter of Oddi (SO) during fasting or after feeding. We implanted electrodes on the distal SO, proximal SO, gastric antrum, duodenum, and jejunum of 20 animals. A cut transection and reanastomosis was done at different levels of the SO to interrupt putative extrinsic or intrinsic nerves, or the SO was painted with phenol to impair extrinsic nerves. Like controls, animals with a cut and reanastomosis at the proximal SO or at the SO-duodenal junction showed a normal fasting pattern of cyclic changes in SO spike-burst rate. In contrast, animals treated by a distal SO cut or phenol treatment at the distal SO lost the normal cyclic pattern of SO spike bursts and had a constant rate of approximately 4/min. A cut through the middle SO uncoupled the spike bursts in the proximal and distal SO. After feeding, all animals developed an SO spike-burst rate of 5-6/min that lasted for several hours. We conclude that the normal fasting pattern of SO spike bursts is regulated by extrinsic nerves that ascend cephalad along the sphincter segment, whereas the sustained increase in SO spike-burst rate after feeding is at least in part hormonal.
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Braun, Fabian, Tobias B. Huber, and Victor G. Puelles. "Proximal tubular dysfunction in patients with COVID-19: what have we learnt so far?" Kidney International 98, no. 5 (November 2020): 1092–94. http://dx.doi.org/10.1016/j.kint.2020.09.002.
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Helm, J. F., W. J. Dodds, J. Christensen, and S. K. Sarna. "Intramural neural control of opossum sphincter of Oddi." American Journal of Physiology-Gastrointestinal and Liver Physiology 257, no. 6 (December 1, 1989): G925—G929. http://dx.doi.org/10.1152/ajpgi.1989.257.6.g925.
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We evaluated the intramural neural control of the opossum sphincter of Oddi (SO) in an in vitro preparation. Force transducers were used to record contractions at four sites along the sphincter segment. To stimulate intramural nerves, 10- to 120-s trains of pulses (4-10 V amplitude, 0.5 ms duration, and 5 Hz frequency) were delivered to one of three electrode pairs implanted along the SO. Electrical stimulation in the proximal, mid, or distal SO elicited phasic contractions that invariably originated in the proximal SO and propagated antegrade along the entire length of the sphincter segment. Stimulus-evoked contractions resembled spontaneous antegrade peristaltic contractions, but occurred at a higher rate (12-20/min). Atropine completely blocked this excitatory response to nerve stimulation. After atropine, nerve stimulation in the proximal, mid, or distal SO abolished spontaneous contractions at and distal to the site of stimulation for the duration of the stimulus. The inhibitory response to nerve stimulation was completely blocked by tetrodotoxin but was unaffected by phenoxybenzamine, tolazoline, or propranolol. We conclude that 1) the opossum SO is innervated by intramural cholinergic excitatory nerves and nonadrenergic noncholinergic inhibitory nerves; 2) cholinergic excitatory nerves are organized in ascending neural pathways, whereas nonadrenergic noncholinergic inhibitory nerves descend along the length of the SO; and 3) these neural pathways may modulate SO peristalsis in vivo and participate in ascending excitatory and descending inhibitory reflexes.
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Burkhart, Harold M., Jess L. Thompson, and Sabrina D. Phillips. "Proximal aortic aneurysms in patients with conotruncal anomalies: Size matters…but so do other things." Journal of Thoracic and Cardiovascular Surgery 154, no. 1 (July 2017): 210–11. http://dx.doi.org/10.1016/j.jtcvs.2017.02.004.
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Helm, J. F., W. J. Dodds, J. Christensen, and S. K. Sarna. "Control mechanism of spontaneous in vitro contractions of the opossum sphincter of Oddi." American Journal of Physiology-Gastrointestinal and Liver Physiology 249, no. 5 (November 1, 1985): G572—G579. http://dx.doi.org/10.1152/ajpgi.1985.249.5.g572.
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We evaluated the control mechanism of peristaltic contractions in the opossum sphincter of Oddi (SO) by means of an in vitro preparation. At each of four sites spaced uniformly along the sphincter segment, a force transducer recorded contractions while a monopolar electrode recorded myoelectric activity. Spontaneous myoelectric and contractile activity occurred in 15 of the 20 intact SO specimens studied. Electrical recordings showed characteristic control waves and response activity. Each control wave was invariably accompanied by a phasic contraction, irrespective of whether or not response activity was superimposed on the control wave. The predominant motor activity of the SO was antegrade peristalsis. Retrograde peristalsis occurred when antegrade peristalsis failed to traverse the entire sphincter. Spontaneous SO phasic contractions were not antagonized by tetrodotoxin. Muscle rings sectioned from the SO exhibited spontaneous phasic contractions with a proximal-to-distal gradient of intrinsic contraction frequencies. We conclude that a) the frequency of SO phasic contractions is determined by control wave frequency, b) spontaneous SO peristalsis is myogenic in origin and may be modeled by a linear array of bidirectionally coupled relaxation oscillators, c) the predominance of antegrade peristalsis may be explained by a high-frequency oscillator in the proximal SO that drives the slower, more distal oscillators, d) retrograde peristalsis is initiated by an ectopic oscillator in the distal SO when antegrade contractions fail to propagate the entire length of the SO, and e) ectopic SO contractions can propagate retrograde when the more proximal oscillators are not in their absolutely refractory state.
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Hedenborg White, Manon. "Proximal Authority." Aries 21, no. 1 (December 14, 2020): 69–93. http://dx.doi.org/10.1163/15700593-02101008.
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Abstract In 1920, the Swiss-American music teacher and occultist Leah Hirsig (1883–1975) was appointed ‘Scarlet Woman’ by the British occultist Aleister Crowley (1875–1947), founder of the religion Thelema. In this role, Hirsig was Crowley’s right-hand woman during a formative period in the Thelemic movement, but her position shifted when Crowley found a new Scarlet Woman in 1924. Hirsig’s importance in Thelema gradually declined, and she distanced herself from the movement in the late 1920s. The article analyses Hirsig’s changing status in Thelema 1919–1930, proposing the term proximal authority as an auxiliary category to Max Weber’s tripartite typology. Proximal authority is defined as authority ascribed to or enacted by a person based on their real or perceived relational closeness to a leader. The article briefly draws on two parallel cases so as to demonstrate the broader applicability of the term in highlighting how relational closeness to a leadership figure can entail considerable yet precarious power.
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Jun-Feng, Chai, and Wang Shu-Yan. "Particle Swarm Optimization-Proximal Point Algorithm for Nonlinear Complementarity Problems." Mathematical Problems in Engineering 2013 (2013): 1–5. http://dx.doi.org/10.1155/2013/808965.
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A new algorithm is presented for solving the nonlinear complementarity problem by combining the particle swarm and proximal point algorithm, which is called the particle swarm optimization-proximal point algorithm. The algorithm mainly transforms nonlinear complementarity problems into unconstrained optimization problems of smooth functions using the maximum entropy function and then optimizes the problem using the proximal point algorithm as the outer algorithm and particle swarm algorithm as the inner algorithm. The numerical results show that the algorithm has a fast convergence speed and good numerical stability, so it is an effective algorithm for solving nonlinear complementarity problems.
Dissertations / Theses on the topic "Proximal-SO"
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Woods, Charmaine Michelle, and charmaine woods@flinders edu au. "EXOGENOUS PURINES INDUCE DIFFERENTIAL RESPONSES IN THE PROXIMAL AND DISTAL REGIONS OF THE SPHINCTER OF ODDI: PARTIAL CHARACTERISATION OF THE PURINERGIC RECEPTOR SUB-TYPES INVOLVED." Flinders University. School of Medicine, 2006. http://catalogue.flinders.edu.au./local/adt/public/adt-SFU20061120.095902.
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The sphincter of Oddi (SO) is a neuromuscular structure located at the junction of the bile and pancreatic ducts with the duodenum. The primary functions of the SO are to regulate the delivery of bile and pancreatic juice into the duodenum, and to prevent reflux of duodenal contents into the biliary and pancreatic systems. Neural, hormonal or functional disturbances of biliary motility can lead to painful and sometimes life threatening clinical conditions, such as SO dysfunction and acute pancreatitis. Clearly understanding the regulation of biliary and duodenal motility patterns is necessary and may provide useful pharmacological sites for drug development to aid in the treatment of these diseases.
Spontaneous activity of the SO is regulated by complex interactions between the enteric nervous system, hormones, possibly interstitial cells of Cajal and other bioactive agents, together with modulation via neural reflexes between the duodenum, common bile duct/gallbladder, and stomach. Purines are one group of neurotransmitters/regulatory agents that have been shown to effect gastrointestinal motility, however their functions in the regulation of SO motility have not been elucidated.
The studies described in this thesis used in vitro organ bath techniques and in vivo preparations to determine the effects of exogenous purines on possum SO and duodenal motility. The possum SO has been extensively characterized and is an excellent model for motility studies. In vitro, exogenous adenosine was found to decrease spontaneous activity in both the SO and duodenum. In contrast exogenous ATP induced both excitatory and inhibitory responses in the SO and duodenum. Interestingly, the adenosine and ATP-induced effects were predominantly exhibited by the proximal portion of the SO (proximal-SO), with no or little effect observed in the distal portion of the SO (distal-SO). These data support the hypothesis that the SO is comprised of different functional components that can act differently in response to certain stimuli, and highlights the importance of studying each of the SO components.
Agonists and antagonists, together with immunohistochemical studies, were used in an attempt to identify the P1 and P2 receptor sub-types responsible for mediating the adenosine- and ATP-induced responses. In the duodenum the adenosine-induced decrease in spontaneous activity was likely to be mediated by A2A and A3 receptors, but the receptors mediating the proximal-SO response could not be identified. In the duodenum ATP induced a complex non-neural response consisting of a P2X1, and P2Y2 and/or P2Y4 mediated immediate inhibition. This was followed by a return to baseline activity or small excitation. The response concluded with a late inhibitory response, likely to be mediated by P2Y1 receptors, but the effects of other P2Y receptors could not be excluded. In contrast, ATP application to the proximal-SO evoked a partially neurally mediated early excitation, likely via P2X receptors, followed by an inhibition of activity, likely via activation of non-neural P2Y2 and/or P2Y4 receptors.
In vivo studies with exogenous application of adenosine and ATP to the SO activated neural pathways to produce increased motor activity. Characterisation of these neural pathways found ATP and/or adenosine to activate excitatory cholinergic motor neurons. ATP also activated an inhibitory nicotinic/nitrergic pathway.
This is the first comprehensive investigation of the possible involvement of purines in the regulation of SO motility. These studies demonstrate that exogenous purines influence SO and duodenal motility, inducing complex neural and non-neural responses, acting via multiple P1 and P2 receptors. It now remains to be determined if endogenously released purines induce similar responses, together with elucidation and location of the receptor sub-types involved.
Books on the topic "Proximal-SO"
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Bockenhauer, Detlef, and Robert Kleta. Approach to the patient with renal Fanconi syndrome, glycosuria, or aminoaciduria. Edited by Robert Unwin. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780199592548.003.0041_update_001.
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Up to 80% of filtered salt and water is returned back into the circulation in the proximal tubule. Several solutes, such as phosphate, glucose, low-molecular weight proteins, and amino acids are exclusively reabsorbed in this segment, so their appearance in urine is a sign of proximal tubular dysfunction. An entire orchestra of specialized apical and basolateral transporters, as well as paracellular molecules, mediate this reabsorption. Defects in proximal tubular function can be isolated (e.g. isolated renal glycosuria, aminoacidurias, or hypophosphataemic rickets) or generalized. In the latter case it is called the Fanconi–Debre–de Toni syndrome, based on the initial clinical descriptions. However, in clinical practice it is usually referred to as just the ‘renal Fanconi syndrome’. Severity of proximal tubular dysfunction can vary, and may coexist with some degree of loss of glomerular filtration capacity. Causes include a wide range of insults to proximal tubular cells, including a number of genetic conditions, drugs and poisons.
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Hughes, Jeremy. Proteinuria as a direct cause of progression. Edited by David J. Goldsmith. Oxford University Press, 2015. http://dx.doi.org/10.1093/med/9780199592548.003.0137.
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Proximal tubular cells reabsorb any filtered proteins during health via cell surface receptors such as megalin and cubulin so that very low levels of protein are present in the excreted urine. Significant proteinuria is a common finding in patients with many renal diseases. Proteinuria is a marker of glomerular damage and podocyte loss and injury in particular. The degree of proteinuria at presentation or during the course of the disease correlates with long-term outcome in many renal diseases. Proteinuria per se may be nephrotoxic and thus directly relevant to the progression of renal disease rather than simply acting as a marker of the severity of glomerular injury and podocytes loss. Seminal studies used the atypical renal anatomy of the axolotl to instill proteins directly into the tubular lumen without requiring passage through the glomerulus. This indicated that tubular protein could be cytotoxic and induce interstitial inflammation and fibrosis in the peritubular region. Cell culture studies demonstrate that exposure to proteins results in proximal tubular cell activation and the production of pro-inflammatory and pro-fibrotic mediators. Proximal tubular cell death occurred in some studies reinforcing the potential of protein to exert cytotoxic effects via oxidative stress or endoplasmic reticulum stress. Analysis of renal biopsy material from both experimental studies using models of proteinuric disease or patients with various proteinuric diseases provided evidence of activation of transcription factors and production of chemokines and pro-inflammatory mediators by proximal tubular cells. These data strongly suggest that although proteinuria is the result of glomerular disease it also represents an important cause of progression in patients with chronic kidney disease associated with proteinuria.
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Giddins, Grey. Nerve injuries. Oxford University Press, 2011. http://dx.doi.org/10.1093/med/9780199550647.003.012025.
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♦ Nerve injuries are common♦ The history is usually clear but the examination may be less so♦ Neurophysiology is only useful after 3 weeks♦ Imaging is of limited value as yet♦ Treatment is removal of the cause/repair as appropriate♦ Recovery is dependent upon many factors especially patient age, severity of the injury, how proximal the injury is and the type of nerve♦ Post operative therapy is crucial♦ Late reconstruction is primarily for motor function.
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Evangelista, Arturo, and T. González-Alujas. Diseases of the aorta. Oxford University Press, 2011. http://dx.doi.org/10.1093/med/9780199599639.003.0023.
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Evaluation of the aorta is a routine part of the standard echocardiographic examination, because echocardiography plays an important role both in the diagnosis and follow-up of aortic diseases. In particular, echocardiography is useful for assessing aorta size, biophysical properties, and atherosclerotic involvement of the thoracic aorta.Transthoracic echocardiography (TTE) permits adequate assessment of several aortic segments, particularly the aortic root and proximal ascending aorta. Transoesophageal echocardiography (TOE) overcomes the limitations of TTE in thoracic aorta assessment, so TTE and TOE should be used in a complementary manner.Although TOE is the technique of choice in the diagnosis of aortic dissection, TTE may be used as the initial modality in the emergency setting. Intimal flap in proximal ascending aorta, pericardial effusion/tamponade, and left ventricular function can be easily visualized by TTE. However, a negative TTE does not rule out aortic dissection and other imaging techniques must be considered. TOE should define entry tear location, mechanisms of aortic regurgitation, and true lumen compression.In addition, echocardiography is essential in selecting and monitoring surgical and endovascular treatment and in detecting possible complications. Although other imaging techniques have a greater field of view, echocardiography is portable, rapid, accurate, and cost-effective in the diagnosis and follow-up of most aortic diseases.
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Bernstein, Lori J. Ambiguous Figures Moving Forward. Oxford University Press, 2017. http://dx.doi.org/10.1093/acprof:oso/9780199794607.003.0095.
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There is inherent ambiguity in visual proximal stimuli, yet only under special circumstances is this obvious. There are many explanations for how we so effortlessly disambiguate inherently ambiguous shape information. An ambiguous figure is a type of optical illusion in that it can give rise to multistable interpretations. Some famous examples of these types of two-dimensional figures include the face/vase and the Necker wire cube. This chapter reviews evidence showing that direction of motion impacts this process. Specifically, a moving ambiguous figure is more likely to be “seen” as the object that faces in the direction of perceived motion. This “heading effect” appears to hold up even when the motion is nonoptimal and is far from biologically accurate, as the accompanying demonstration shows. Some possible explanations for this effect are presented and insights from basic neuroscience, neuropsychological cases, and other behavioral studies are discussed.
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Wagner, Carsten A., and Olivier Devuyst. Renal acid–base homeostasis. Edited by Robert Unwin. Oxford University Press, 2015. http://dx.doi.org/10.1093/med/9780199592548.003.0024.
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The kidney is central to acid–base homeostasis. Major processes are reabsorption of filtered bicarbonate, de novo synthesis of bicarbonate from ammoniagenesis, and net excretion of protons. The latter requires buffers such as ammonium, phosphate, citrate and other bases binding protons (so-called titratable acids). The proximal tubule is the major site of bicarbonate reabsorption and only site of ammoniagenesis. The thick ascending limb and the distal convoluted tubule handle ammonia/ammonium and complete bicarbonate reabsorption. The collecting duct system excretes protons and ammonium, but may switch to net bicarbonate secretion. The kidney displays a great plasticity to adapt acid or bicarbonate excretion. Angiotensin II, aldosterone and endothelin are involved in regulating these processes, and they induce morphological changes along the nephron. Inborn and acquired disorders of renal acid–base handling are caused by mutations in acid–base transport proteins or by dysregulation of adaptive mechanisms.
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Menon, Ashok, and Haris A. Khwaja. Complications of Jejunoileal Bypass. Edited by Tomasz Rogula, Philip Schauer, and Tammy Fouse. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780190608347.003.0035.
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Jejunoileal bypass (JIB) was a malabsorptive bariatric procedure developed in the 1950s based on pioneering work in canine models. All described variants involved anastomosis between the proximal jejunum and terminal ileum. Long-term weight loss and improvement in hyperlipidemia were found to be particularly impressive. However, it became clear by the 1980s that morbidity and mortality associated with JIB were unacceptably high. The procedure was abandoned, and many patients underwent reversal to normal intestinal continuity, or revision to other bariatric procedures. Two main mechanisms underlie the complications with JIB. Malabsorption caused excessive diarrhea, nutritional and metabolic failure, and hyperoxaluria, leading to urolithiasis. Bacterial overgrowth in the defunctioned small intestine was thought to lead to immune complex-mediated development of inflammatory arthritis, and the so-called bypass enteritis syndrome. A combination of these two mechanisms was thought to be responsible for hepatic dysfunction and failure after JIB.
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de Bie, Robertus M. A., and Susanne E. M. Ten Holter. “She Is So Fidgety”. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780190607555.003.0023.
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Chorea manifests as involuntary, often contnuous, unpredictable, and involuntary dance-like movements. Patients with chorea are often unaware that they have involuntary movements. Others may try to incorporate the movement into a semipurposeful action (parakinesia). Chorea is usually worse with mental activity or emotion. Physical activity may also exacerbate chorea. The presence of “motor impersistence” is typical of chorea. Sometimes patients can also make unintentional sounds referred to as hyperkinetic dysarthria. Chorea disappears during sleep. Ballism is considered a type of chorea with a more proximal distribution and larger movements. Athetosis is a term formally used for chorea with slow writing movements in the distal limbs, but it is not considered a specific entity of chorea anymore. The most important genetic cause of chorea in adulthood is Huntington’s disease, and genetic testing should be considered as a first step in all patients with adult-onset chorea if no secondary cause is found.
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Biswas, Santanu, and John J. Frank. Management of pericardial tamponade. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780199600830.003.0167.
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Cardiac tamponade is an emergency, and definitive therapy is fluid removal by pericardiocentesis. In certain conditions, fluid removal is still the optimal choice, but a conservative approach using haemodialysis may be employed. Factors that influence the management strategy include evaluating the cause, providing haemodynamic support, and choosing the technique. Fluid resuscitation to maintain venous pressure and circulation may be beneficial up to a point, after which, tamponade may be aggravated. While inotropes have theoretical benefit, studies involving humans are few. Fluid removal strategies are broadly grouped into percutaneous and surgical methods. In most cases, the percutaneous approach is favoured. However, surgery is typically the first choice in blunt trauma or in proximal aortic dissection. While the safety of percutaneous methods is well established, imaging guidance is needed to avoid common complications associated with a blind technique. The proper management strategy should also minimize effusion recurrence, common methods to do so include placement of a drainage catheter, infusion of a sclerosing agent, and a balloon pericardiotomy procedure. Surgical methods for removal of pericardial fluid include the creation pericardial window, insertion of a pericardioperitoneal shunt, and pericardiectomy. The creation of a pericardial window and pericardioperitoneal shunt are safe, but pericardiectomy is associated with increased morbidity. After fluid removal has been completed, the patient should be placed in a unit that is both familiar with the signs of tamponade and has the capacity to quickly treat a significant effusion if it recurs.
Book chapters on the topic "Proximal-SO"
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Diezma Iglesias, Belén. "Proximal vegetation sensors." In Manuali – Scienze Tecnologiche, 14. Florence: Firenze University Press, 2020. http://dx.doi.org/10.36253/978-88-5518-044-3.14.
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In this topic the basic principles of sensors to gather information about plant status are explained. Mainly optical sensors, but also systems based or other principles, vegetation sensors will be presented as well as their use to register information about crop health, physiological activity, possible pest infestation, water content, and so on. Information acquired by these sensors (normally optical signals) must be processed adequately and, in many cases, converted into vegetation indexes that will be presented for different cases of usage.
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Green, David J. "Scapula, clavicle, and proximal humerus." In Hominin Postcranial Remains from Sterkfontein, South Africa, 1936-1995, 37–48. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780197507667.003.0005.
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This chapter describes parts of four scapulae, two clavicles, and three proximal humeri, and provides information on the functional anatomy of the Sterkfontein hominin pectoral girdle and shoulder joint. The clavicle resembles that of other hominins, which indicates a more horizontal orientation than in apes. Comparative analysis of these scapulae, though, suggests that the glenohumeral joint of Australopithecus africanus is more cranially oriented than typical for humans, perhaps even more so than seen in East African early hominins. This morphology may also indicate features of dorsal scapular shape, which could impact potential areas of attachment as well as line of action of dorsal rotator cuff muscles. The glenohumeral joint morphology and orientation implies the possibility of more arboreality in the A. africanus locomotor repertoire.
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Emmett, Stevan R., Nicola Hill, and Federico Dajas-Bailador. "Renal medicine." In Clinical Pharmacology for Prescribing. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780199694938.003.0013.
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The kidneys are of fundamental importance in the regulation of fluid and electrolytes, maintaining permissive extracellular fluid composition (salts and water), pH, and volume, while also mediating the removal of waste products. Based on the anatomy of the nephron, three main processes occur in order to deliver this balance: glomerular filtration, tubular secretion, and tubular resorption. Drugs can act at different sites within this system, so that functional equilibrium can be restored in various disease states (e.g. hypertension, heart failure, liver failure, nephrotic syndrome). CKD is a long- term condition that lasts more than 3 months and affects the function of both kidneys. It results from any pathology that reduces renal functional capacity and produces a decrease in GFR to less than 60 mL/ min/ 1.73 m<sup>2</sup>. Prevalence within the UK is high, particularly in the elderly and affects 6– 8% of the population. The most common cause of CKD is idiopathic (unknown, usually with small kidneys), then diabetes mellitus. In both, glomerular damage and mesangial injury (causing metabolic and haemodynamic effects) occur. Mild- moderate essential hypertension does not cause CKD. Knowledge of the functional anatomy of the proximal tubule and loop of Henle is essential in understanding therapeutic targets and treatment of pathologies, as each region and transporter system has a key role. In brief, the journey of solutes from the blood to the production of urine occurs at five main anatomical sites— the glomerulus, the proximal tubule, the loop of Henle, the distal tubule (proximal part and distal part), and the collecting ducts (Figures 5.1 and 5.2). The glomerulus is a network of capillaries (like a ball of string), which merge with the nephron via Bowman’s capsule. It is the first site of filtration and the place where solutes, toxins, and small proteins are removed from the wider circulatory system, after delivery by the renal arteries (via an afferent arteriole). Blood and larger proteins remain in the arteriole and leave via an efferent branch, while the filtrate enters the proximal convoluted tubule. The afferent:efferent system ensures that a constant filtration pressure is maintained irrespective of variations in arterial pressure. The capillary bed is very large, so that permeability and filtration rates are high. A normal glomerular filtration rate (GFR) i.e. 90– 120 mL/ min/ 1.73 m<sup>2</sup>, depends on hydrostatic pressure, the colloid osmotic pressure and hydraulic per¬meability.
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Kakkori, Leena, and Rauno Huttunen. "Vygotsky, Heidegger, and Gadamer on Moral Development." In Contemporary Approaches to Activity Theory, 323–36. IGI Global, 2015. http://dx.doi.org/10.4018/978-1-4666-6603-0.ch019.
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The authors present a Heideggerian-Gadamerian interpretation of Vygotsky from the point of view of moral learning. In doing so, they introduce a new concept called Hermeneutic Zone of Proximal Development (HZPD). They also connect HZPD to the self-education of one's moral voice and lifelong moral learning. Adult self-education includes activities like reappraisal of moral choices, improving moral imagination, especially concerning fellow feeling, and dissimulating unproductive moral feelings in order to convert them into productive moral feelings. The purpose of critical self-reflection of one's moral voice is to transform “everyday morality” into “deliberative morality.”
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Drapeau, Michelle S. M., and Colin G. Menter. "Ulna and radius." In Hominin Postcranial Remains from Sterkfontein, South Africa, 1936-1995, 65–98. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780197507667.003.0007.
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Descriptions of all radial and ulnar fossils from Sterkfontein are presented. The relatively large sample of forelimb bones from Sterkfontein provide information about the elbow, wrist, and forearm of Australopithecus africanus. The proximal orientation of the olecranon process and anterior orientation of the trochlear notch suggest that the forelimb was used in flexed position, as in humans. The bones are small relative to other hominins, and have relatively straight diaphysis and small muscle attachment markings like other australopiths, suggesting the presence of reduced forearm muscularity relative to apes. Diaphyseal cross-sectional shape suggests a pattern of forearm muscle use that may be neither completely human-like nor ape-like but somewhat intermediate, perhaps reflecting a reduced use in locomotion and an increased use in manipulation. In contrast to the diaphysis, the proximal radius is more clearly ape-like, with beveled heads and constricted and relatively long necks comparable to the Hadar specimens, which underscores the unique morphology of the elbow (neither completely human-like nor ape-like) in these hominins. The distal ulna, with the well-marked tendon groove, deep fovea, and a head shape intermediate between apes and humans, like A. afarensis specimens, suggest that stability was required during loading and use of the hand and wrist, although possibly less so than in extant apes. The overall picture of the Sterkfontein forelimb is that of a taxon that had powerful arms, but less powerful than apes, and that they were using them for tasks such as manipulation and probably less so for locomotion.
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Ward, Thomas J., David G. Mobley, and Joshua Weintraub. "Nonvascular Interventions: The Gastrointestinal System." In Interventional Radiology, edited by Bradley B. Pua, Anne M. Covey, and David C. Madoff, 512–22. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780190276249.003.0039.
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The interventional radiologist has a diverse and expanding role to play in the management and treatment of patients with disorders of the gastrointestinal (GI) system. These patients generally fall into one of two broad categories. The first category includes patients who are unable to tolerate or achieve adequate nutrition by mouth. In these patients, the interventional radiologist may be consulted to obtain percutaneous enteral access so that nutrition or hydration may be administered. The second category includes patients with benign or malignant strictures or obstruction of a hollow viscus, be it the esophagus, stomach, or small or large bowel. In these patients, the goal is to treat the obstruction when possible, or else decompress proximal to the obstruction for palliation of symptoms.
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Kaur, Raminder. "Discipline and Deviance." In Kudankulam, 198–226. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780199498710.003.0007.
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Chapter 7 focuses on the attempt to collate data and create an evidence base to inform an anti-nuclear movement through a survey on radiation readings and proximal health problems. Such endeavours signal a tactic that emerged around the turn of the new millennium in the region—one that draws upon the relevance of data and calls upon a politics of transparency for all public authorities even while nuclear agencies see themselves as off-limits. We learn about what may be described as an ‘indigenous survey’, a statistical methodology that was pursued by local residents to produce data that might challenge state-sanctioned information regarding public health, radiation, and the environment in a region of high background radiation and atomic mineral sandmining. The survey organizers aimed to embolden a space of criticality with supportive facts so as to present themselves as knowledgeable and rational, and thereby enter more forcefully into debate with state officials.
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Friedman, Jeffrey D., and Eric S. Ruff. "Soleus Flap for Lower Leg Reconstruction." In Operative Plastic Surgery, edited by Gregory R. D. Evans, 873–80. Oxford University Press, 2019. http://dx.doi.org/10.1093/med/9780190499075.003.0086.
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Open wounds in the middle third of the lower leg often require soft tissue reconstruction to allow for primary wound healing. The soleus muscle flap is uniquely suited for this purpose and is used primarily as a muscle flap without the accompanying overlying skin. This muscle has a blood supply that is segmental in nature, arising from multiple perforators from the posterior tibial vessels. Given that that this blood supply is primarily located in the proximal third of the leg, the soleus muscle flap is generally based proximally to allow for coverage of middle-third defects. While the muscle has a clear intermuscular septum which separates the medial head from the lateral segment, the use of a so-called hemi-soleus flap is less reliable and thus used on an infrequent basis. The soleus muscle flap can also be based distally in the leg for small distal-third defects; however, this flap can often be unreliable due to a paucity of sufficient perforators located in this area.
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Fleeson, William, R. Michael Furr, Malek Mneimne, and Elizabeth Mayfield Arnold. "Using Basic Personality Process Models to Inform the Personality Disorders." In Using Basic Personality Research to Inform Personality Pathology, edited by Douglas B. Samuel and Donald R. Lynam, 73–93. Oxford University Press, 2019. http://dx.doi.org/10.1093/med-psych/9780190227074.003.0004.
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This chapter argues that models articulating the processes underlying normal personality traits, even more so than the structure of normal traits, may help to inform research on personality disorders (PDs). It first describes whole trait theory as a model of normal traits that focuses on process at the same time that it is based on normal personality structure. The chapter then shows how this model makes an easy translation to process models of borderline personality disorder, thereby forming a connection between normal personality and pathological personality at a process level. The resulting general model of borderline personality disorder suggests viewing PD symptoms as distinct, momentary events rather than as stable, enduring features of people. It argues that etiological theorizing should include the proximal mechanisms that lead to temporally bounded symptoms. For example, relationship instability is seen not as a feature of the person but as an event that flares up and then fades repeatedly, in response to events and interpretations of those events. Accumulating evidence in support of this model is described. A model connecting normal personality trait processes to pathological personality processes may strengthen the connection between normal personality and pathological personality more firmly.
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Shewring, David J. "Fractures of the hand and wrist." In Oxford Textbook of Plastic and Reconstructive Surgery, edited by Vivien Lees and James Haeney, 409–34. Oxford University Press, 2021. http://dx.doi.org/10.1093/med/9780199682874.003.0148.
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Fractures of the phalanges and metacarpals are the most common fractures of the upper limb and account for 10% of all fractures. Along with fractures of the carpal bones, they represent 55% of upper extremity fractures. Although over the last few decades there has been an increased tendency to treat hand fractures with internal fixation, the vast majority of these fractures are stable and can (and should) be treated non-operatively. If surgical fixation is considered, then it must be appreciated that some hand fractures, particularly those affecting the proximal phalangeal shaft and intra-articular fractures, can be unforgiving. Fractures treated poorly, using inappropriate equipment in inexperienced hands can lead to irretrievably poor outcomes. Good or perfect results can be obtained with surgical fixation, but these demand careful planning with consideration of all the various methods in the surgical repertoire. The best, and possibly the only opportunity to obtain a good result is at the first surgical intervention and so those fractures requiring fixation should not be treated by unsupervised inexperienced surgeons. It is preferable to delay fixation by a few days until the best expertise is available.
Conference papers on the topic "Proximal-SO"
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Nawathe, Shashank, Alissa Romens, Mary L. Bouxsein, and Tony M. Keaveny. "High-Risk Tissue Distribution in the Human Proximal Femur Under Sideways Fall Loading." In ASME 2012 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/sbc2012-80639.
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Despite the central role of femoral strength in the etiology of osteoporotic hip fractures [1], the associated micromechanical basis of femoral strength remains poorly understood. Cadaver studies [2] using biomechanical testing have established that both the cortical and trabecular bone contribute to the structural integrity of the proximal femur but these studies did not address mechanisms. Addressing mechanisms, theoretical and finite element continuum analyses have assessed cortical-trabecular load sharing and have described stress and strain distributions throughout the proximal femur [1,3]. However, the regions of the bone at highest risk of initial failure remain unclear, in part because the continuum nature and low spatial resolution of these previous analyses render them incapbable of capturing load transfer associated with the microstructure of the trabecular bone and the sometimes thin cortex. Overcoming this limitation, micro-CT-based finite element analysis has recently been applied to the entire proximal femur [4], but so far only two femurs have been analyzed and thus reported trends are difficult to generalize. To extend this recent work and provide further insight into the microstructural basis of femoral strength, we applied micro-CT based finite element analysis to investigate femoral micro-mechanics in a cohort of elderly human proximal femurs.
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Campos, Lucas, Francis Bourbonnais, Ilian A. Bonev, and Pascal Bigras. "Development of a Five-Bar Parallel Robot With Large Workspace." In ASME 2010 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/detc2010-28962.
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Five-bar planar parallel robots for pick and place operations are always designed so that their singularity loci are significantly reduced. In these robots, the length of the proximal links is different from the length of the distal links. As a consequence, the workspace of the robot is significantly limited, since there are holes in it. In contrast, we propose a design in which all four links have equal lengths. Since such a design leads to more parallel singularities, a strategy for avoiding them by switching working modes is proposed. As a result, the usable workspace of the robot is significantly increased. The idea has been implemented on an industrial-grade prototype and the latter is described in detail.
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Rawal, B. R., and Naresh Bhatnagar. "An Investigation on the Effect of Groove Dimensions and Inclination on Cementless Femoral Component in Hip Arthroplasty." In ASME 2012 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/sbc2012-80584.
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The optimal surface for a cementless femoral stem has been the subject of debate for the past several years. Several researchers have stressed the need for research on how an implant surface shape contributes to long-term stability, after implantation, in the field of orthopaedics. The introduction of optimized grooves on an implant surface may enhance long-term stability of an implant. This study thus analyzes the effect of different groove dimensions and angles with a transverse plane on stress transmission by a load at the proximal femur by using finite element analysis. Results suggest that the tendency of stress transmission differs depending on the size, position and angle of the grooves. So, optimized groove size and inclination plays a vital role for long-term stability of cementless femoral stems.
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Zaldivar-Colado, Ulises, Xiomara Zaldivar-Colado, Claudia Marmolejo-Rivas, Diego Murillo-Campos, Carlos Leo´n-Sa´nchez, Roberto Bernal-Guadiana, and Carolina Martinez-Tirado. "Optical-Mechanical Motion Capture System for Virtual Reality Applications." In ASME 2011 World Conference on Innovative Virtual Reality. ASMEDC, 2011. http://dx.doi.org/10.1115/winvr2011-5544.
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Actually, virtual reality is introduced in so many areas, such as medicine, automotive industry, robotics, entertainment, etc. A common interest of these areas is related with the user interaction, or with devices allowing users to interact with virtual reality. In this work we present the development of a prototype to capture the user’s fingers motion, obtaining the flexion angles of the fingers and representing them in a virtual assembly environment. The developed prototype is composed by a mechanical system which transmits the generated flexion movements of the medial and proximal phalanges. The movement is transmitted using a nylon cable, which is captured by the use of a webcam. The offset of the cable is measured, and this permits to obtain the angular variation of the generated flexion by the phalanges. The Lucas-Kanade algorithm is used to follow, in a high velocity, the cable displacement. Experimental results showed that angular resolution is very high and angular capture-rate is over 30fps. We present an implementation of our prototype in a virtual assembly environment.
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Fazel Bakhsheshi, Mohammad, Florian Vixege, and Dana Grecov. "Reduction of the Aortic Aneurysm Sac Pressure Using a Stent With Venturi Structure: A Numerical Study." In 2018 Design of Medical Devices Conference. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/dmd2018-6919.
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Aortic aneurysm is a common disorder which is due to weakening of the aortic wall [1]. Aneurysm rupture is a potentially life threatening complication [2]. The stent graft implantation is one of the potential alternatives for treating patients at high risk for an open surgical procedure. The short-term outcome for stent implantation is promising; however, as with any medical procedure, this has potential limitations such as side branch occlusion, device malfunctions, dilatation at the proximal portion and the so called ‘endoleak’. An endoleak is the persistent blood flow into and within the aneurysmal sac after endovascular repair (i.e. the blood leaks around the endograft which is supposed to have sealed off the entry of blood around it and can be classified into 5 categories[3]). Type I (inadequate seal) and III (graft mechanical failure) endoleaks, characterized by direct communication between systemic and aneurysm sac compartments, pose higher risk of aneurysm rupture and are therefore aggressively treated [4]. Despite advances in the treatment of aneurysm, we believe that there is a still great need for a medical device that can improve patient outcomes.
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Pavlin, B., G. Carabin, G. Pernigotto, A. Gasparella, and Renato Vidoni. "An Embedded Mechatronic Device for Real-Time Monitoring and Prediction of Occupants’ Thermal Comfort." In ASME 2018 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/imece2018-87632.
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It is well recognized in the literature that thermal sensation and comfort are dependent on both core and skin temperatures. In particular, some regions of the human skin, such as the forehead, have a higher density of thermal receptors, giving a higher sensitivity to the skin temperature. Some studies suggest that the forehead skin temperature and its rate ofchange alone could potentially be a good indicator of one’s overall thermal comfort. To validate this claim, an idea for a smart sensor which would be able to read the occupants’ forehead temperature and other environmental parameters in a proximal way is here considered. Moreover, with the aim of exploiting the system not only in lab or test facility environments but, considering the 4.0 revolution, also in the building automation context, a non-invasive solution has been searched so as the occupants are not disturbed while the measurement is performed. Therefore, in this study, a new cheap and smart mechatronic sensor device for a non-invasive measurement of the occupants’ thermal comfort is proposed. The main components consist of a central unit, i.e. microprocessor, a small infrared sensor for thermal imaging, i.e a Lepton infrared camera by FLIR, as well as other sensors for measuring distance, humidity and temperature. The setup was imagined as the sensor being placed on the top of each desk, so it is not easily obstructed by a laptop or a similar object that can be found on top of the working surface. After the conceptual hardware definition and software development, an accurate experimental calibration has been performed exploiting an ad-hoc developed set-up based on a hot plate with an emissivity factor similar to the one of the human skin and with adjustable temperature. Finally, a first design for embedding the whole smart mechatronic system in a unique box has been developed and built.
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Ayers, Jessica A., William C. Tang, and Zhongping Chen. "Paraffin Actuated Micromirror for Endoscopic OCT." In ASME 2009 4th Frontiers in Biomedical Devices Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/biomed2009-83051.
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Microelectromechanical systems (MEMS) have great potential for use in gastrointestinal (GI) imaging. Ultrasound and magnetic resonant imaging can provide useful information about the GI tract, but only optical coherence tomography (OCT) delivered endoscopically can be used to perform an optical biopsy of the GI tissue. In monitoring a condition such as Barrett’s esophagus, which typically requires regular random biopsies, the ability to achieve an optical biopsy is indispensible. While the existing method for obtaining an optical biopsy of the GI tract tissue produces functional images, there are drawbacks that could be improved upon. The gear-and-shaft assembly used to couple force from the motor at the proximal end to the distal imaging end requires a complex design [1]. By introducing a rotational MEMS device into the distal imaging end, a rotating optical coupling joint is no longer required at the proximal end, there is no need to precisely align the fixed fiber with the rotational drive shaft, and the metallic reinforcement sleeve can be eliminated leaving a simpler, more flexible delivery method [2]. In order to produce 3D OCT images, displacement in the z-direction needs to be coupled with rotation. A MEMS device that can achieve both vertical displacement and rotation further increases the simplicity of the device and decreases potential alignment and coupling errors. Our MEMS devices needs to be able to bend an OCT beam of light 90°, rotate that beam of light 360°, and simultaneously scan in the z-direction in order to produce 3D OCT images. Also, the device must fit inside the 1 mm diameter available in the endoscope. To accomplish this, we have designed, and are continuing to develop, a paraffin actuated micro mirror. The thermal expansion properties of paraffin wax have often been utilized in MEMS devices [3, 4]. We have made use of these properties in designing a piston like actuator. Heat is applied to a reservoir of paraffin enclosed by a parylene membrane. The paraffin expands and pushes the post above it upward with the developed force from its expansion. The amount of paraffin in each reservoir is controlled by the reservoir’s geometry and so by controlling the amount of heat applied, we can control how far the post above it moves in the vertical direction. Each device has three heaters, three reservoirs, and three posts. All three posts are attached to a single mirror. By appropriately cycling the applied heat to each reservoir, we expect to be able to move the mirror in a spiral like fashion. This will bend an applied beam of light 90° and rotate it 360° while achieving displacement in the z-direction.
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Poredoš, P., and V. Videčnik. "THE EFFECT OF HEPARIN ON THERAPEUTIC SUCCESS OF LOCAL STREPTOKINASE TREATMENT OF PERIPHERAL ARTERIAL OCCLUSIONS." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643005.
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In some cases the thrombolytic treatment is not successfull inspite the fact, that lysis of the thrombus occured. This could be the consequence of ascending thrombosis and early reocclusion due to prevailing thrombogenic potential (decreased floow endothelial damage, presence of intraarterial catheter). The aim of the present study was to established if simultaneous heparin administration improves local thrombolytic treatment of arterial occlusions. The study encompassed three groups of patients with acute and subacute arterial occlusions of the lower limbs. In the first group there were 31 patients treated with streptokinase only (SK group). The second group (33 patients) received heparin (450 IU/hour) simultaneously with SK through the proximal opening of the coaxial catheter. Heparin so poured over the distal part of the catheter (SK-H group). In patients of the third group (22 patients) treated as SK-H group, thrombi were before treatment enriched with 7,5 ug of plasminogen (SK-H-Plg group). Patients of all three groups received SK as continuous intraarterial infusion (3750 IU/hour) until recanalisation occured but at most for 3 days. The results of the treatment are shown in the table.Heparin significantly reduced the number of ascending thrombosis along the intraarterial catheter (p<0,05). Although the difference between the number of successfully and unsuccessfully treated patients of the three groups was not statistically significant (the reason for this were probably too small groups) the results suggested that heparin contributed to greater therapeutic success.
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Coemert, S., L. G. Wegener, B. Yalvac, J. Fuckner, and T. C. Lueth. "Experimental and FEM-Based Payload Analysis of Ti-6Al-4V Flexure Hinges." In ASME 2019 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/imece2019-10105.
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Abstract In this work, we investigated the effect of geometric parameters on the payload capacity of Ti-6Al-4V flexure hinges taking plastic deformation as a boundary failure criterion into account. Finite element and experimental analysis were performed in combination to increase the significance of the findings. For both simulations and experiments rectangular cross section flexure hinges were designed with varying thickness, length and width. While varying one of the parameters, the others were kept constant in order to see the individual influence of that particular parameter. The samples were fabricated using laser cutting of Ti-6Al-4V (Grade 5) metal sheets to ensure optimum dimensional accuracy. In the experimental procedure, the samples were fixed at the proximal end and exposed to gradually increasing vertical loads at the distal end by using weights. Simultaneously, they were exposed to a counteracting moment by pull-wire actuation attached on the tip to simulate the realistic actuation-loading behavior. For the sake of a uniform comparison of the samples with different dimensions, a state of equilibrium was defined such that the proximal and distal ends of the hinge were parallel. As soon as this state was achieved, the poses in each loading state were documented by a digital microscope for later postprocessing. On the other hand, the simulations were constructed in a way that permitted the experimental approach to be reflected in the simulation environment as realistically as possible. While performing a deformation-based simulation, the surface on which the payload was acting was blocked against rotation around the lateral axis so that the state of equilibrium could be maintained. The hinges were deflected with gradually increasing deformation in the vertical axis until 0.2% plastic strain occurred in the unloaded state. At this point the deformations in the vertical axis for both loaded and unloaded states were recorded to be compared with the experimental values. The forces leading to the deformation in the loaded state were calculated as output of the simulation and recorded as payload capacity. Consequently, the deformations obtained by analyzing the images captured during the experiments were compared and matched with the ones obtained from the simulations. The experimental loads leading to these deformations were recorded as experimental payload values. In the first step towards the evaluation of the results, payload values obtained from experiments and simulations were compared to check the consistency of the process. Subsequent to verifying the consistency, the effect of the geometric parameters on the payload progression was analyzed based on the simulation results. Nonlinear multidimensional regression was performed to come up with a design guideline which approximates the payload capacity based on the dimensional parameters. The proposed guideline estimates the payload value as proportional to width, inversely proportional to length and proportional to the 1.6th power of thickness.
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Kasra, M., and M. D. Grynpass. "Thorn Implant: A Novel Mechanism for Interamedullary Stem Fixation." In ASME 2002 International Mechanical Engineering Congress and Exposition. ASMEDC, 2002. http://dx.doi.org/10.1115/imece2002-33004.
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Existing non-cemented prostheses fixation mechanisms use press-fit techniques to obtain initial stability between bone and implant. For example, the primary fixation of non-cemented total hip stem prosthesis is achieved by carefully impacting the implant to the broached, contoured proximal femur. A successful primary fixation will be followed by the secondary fixation caused by bone ingrowth into the porous surface of implant. However, the primary postoperative fixation of the implants is usually far from ideal [1, 2]. Theoretically, for bone ingrowth to occur, a porous coated implant must be rigidly fixed with close apposition to the bone, without causing excessive stresses and stains at the bone-implant interface. However, this would require the medullar cavity to be prepared to very tight tolerances. In practice, this press fit technique requires interference fit between the prosthesis and the bone, thus creating large stresses and strains. In this case severe impacts for fitting the prosthesis may also fracture the bone. Therefore, it is important that the broaching and contouring of the femur be carried out carefully and exactly. This results in operations being lengthier and more complex. Furthermore, reaming and broaching damage bone vascular system delaying bone formation. The objective of this study was to introduce a novel fixation method, which can achieve immediate initial stability at the operation without having the mentioned problems of contemporary prosthetic designs. In this method, instead of waiting for the bone ingrowth to occur, pins from the inside of a hollow prosthesis stem are driven into the bone making a thorn implant. Therefore, fixation is achieved by so-called metal ingrowth into the bone instead of bone ingrowth into metal.