Pullout strength and load to failure properties of self-tapping cortical screws in synthetic and cadaveric environments representative of healthy and osteoporotic bone.
Equipment Design; Cadaver; Osteoporosis; Human; Stress; Biological; Models; Mechanical; Orthopedic Fixation Devices; Biomechanics; Bone Substitutes; Materials Testing – Methods
BACKGROUND: The parameters of self-tapping screw (STS) performance in normal and osteoporotic bone have been defined in representative environments, but the question remains as to the clinical application of such findings. The goal of this study was to analyze the biomechanical performance of STSs in cadaveric and synthetic environments representative of healthy and osteoporotic bone. METHODS: Ninety-six Synthes STSs were inserted into cadaveric and synthetic models representative of osteoporotic and healthy bone. Screws were inserted to depths of 1 mm short of the far cortex, flush and 1 mm and 2 mm beyond the far cortex. Screws were tested with an Instron 8511 material testing system utilizing axial pullout forces. A SAS procedure was used to conduct analysis of variance for unbalanced datasets. RESULTS: Substantial differences were appreciated with respect to screw performance between osteoporotic and healthy bone specimens. Although a similar pattern of increased pullout strength and loading energy with increasing depth of insertion was demonstrated, absolute values were lower in osteoporotic specimens. Although performance trends were similar in cadaveric and synthetic testing models for both osteoporotic and healthy bone, values obtained during testing were different. Incomplete insertion of STSs resulted in a 21.5% and 37% reduction of biomechanical properties in osteoporotic and normal bone, respectively. CONCLUSIONS: These results indicate that previously published findings on the performance of STSs in synthetic models cannot reasonably be applied to the clinical realm. Although trends may be similar, screw performance in synthetic, as compared with cadaveric, models is markedly different.
Schoenfeld A J; Battula S; Sahai V; Vrabec GA; Corman S; Burton L; Njus GO
Journal of Trauma
2008
2008-05
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.1097/ta.0b013e318169cd71" target="_blank" rel="noreferrer noopener">10.1097/ta.0b013e318169cd71</a>
Continuous emergency department monitoring of arterial saturation in adult patients with respiratory distress.
Adult; Humans; Middle Aged; Aged; Equipment Design; Evaluation Studies as Topic; Emergencies; Resuscitation; Oximetry/*instrumentation; Oxygen/*blood; 80 and over; Respiratory Distress Syndrome; Monitoring; Adult/*blood; Physiologic/instrumentation
Continuous measurement of arterial oxygen saturation (SaO2) using pulse oximetry has become a common monitoring and management technique in critically ill hospitalized patients. To determine the impact of SaO2 monitoring on emergency patient management, we conducted a prospective uncontrolled clinical trial on 40 adult patients presenting to the emergency department with acute respiratory illness, such as emphysema, asthma, or pulmonary edema. Recorded data included hemograms, arterial blood gases, subsequent therapy, and response to treatment. Additionally, the "early warning" capability of SaO2 monitoring was analyzed by recording the severity and outcome of hypoxemic events during treatment. Mean duration of usage for the 40 oximeters in the ED was 1.8 hours; all probes functioned reliably over a wide range of systolic pressures (80 to 206 mm Hg), heart rates (40 to 180 beats per minute), and hematocrits (20% to 58%). There was good correlation between simultaneous pulse oximeter values and both directly measured SaO2 (r = 0.95) and saturations derived from measured arterial PaO2 (r = 0.94). The device detected several otherwise unrecognized drops in arterial saturation that were confirmed by laboratory analysis. Other clinical situations in which the pulse oximeter was found useful in the ED are reviewed. We conclude that continuous measurement of SaO2 can improve the monitoring of ED patients, increase the precision of therapy, detect hypoxemia during intubation, suctioning, and other treatments, and detect clinically unsuspected changes in arterial oxygenation.
Jones J; Heiselman D; Cannon L; Gradisek R
Annals of emergency medicine
1988
1988-05
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.1016/s0196-0644(88)80237-3" target="_blank" rel="noreferrer noopener">10.1016/s0196-0644(88)80237-3</a>
A novel method for treatment of lumbar spinal stenosis in high-risk surgical candidates: pilot study experience with percutaneous remodeling of ligamentum flavum and lamina.
Adult; Female; Humans; Male; Middle Aged; Aged; Pilot Projects; Follow-Up Studies; Risk Factors; Prospective Studies; Pain Measurement; Equipment Design; Comorbidity; Disability Evaluation; Conscious Sedation; Fluoroscopy; Ligamentum Flavum/*surgery; Lumbar Vertebrae/*surgery; Minimally Invasive Surgical Procedures/*instrumentation; Postoperative Complications/diagnosis/*prevention & control; Spinal Stenosis/*surgery; Anesthesia; Human; Pilot Studies; Middle Age; 80 and over; Local; Ligaments; Decompression; Surgical/*instrumentation; 80 and Over; Spinal Stenosis – Surgery; Postoperative Complications – Diagnosis; Articular – Surgery; Lumbar Vertebrae – Surgery; Minimally Invasive Procedures – Equipment and Supplies; Postoperative Complications – Prevention and Control; Surgical – Equipment and Supplies
OBJECT: treatment of lumbar spinal stenosis (LSS) in chronically ill or debilitated patients is challenging. The percutaneous remodeling of ligamentum flavum and lamina (PRLL) technique is a novel method for decompression of the hypertrophic ligamentum flavum component of LSS that is performed using a fluoroscopically guided percutaneous approach, local anesthesia, and minimal sedation. METHODS: fourteen patients deemed to be at high risk for complications related to open spine surgery and general anesthesia were treated using the PRLL technique. Prospectively collected visual analog scale (VAS) and Oswestry Disability Index (ODI) data were analyzed at the most recent follow-up. The average follow-up duration was 23.5 weeks. RESULTS: a statistically significant improvement in VAS scores was observed, with a reduction in pain of 53% compared with preoperative levels. In contrast, the ODI scores failed to improve. CONCLUSIONS: this pilot series points to a potential new therapeutic option for LSS in high-risk surgical patients.
Chopko Bohdan Wolodymyr
Journal of neurosurgery. Spine
2011
2011-01
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.3171/2010.9.SPINE091012" target="_blank" rel="noreferrer noopener">10.3171/2010.9.SPINE091012</a>
External fixation: how to make it work.
Humans; Magnetic Resonance Imaging; Equipment Design; Prosthesis Design; Fracture Healing; *External Fixators; Fracture Fixation/*methods; *Orthopedic Fixation Devices; Fracture Fixation/*instrumentation; Minimally Invasive Surgical Procedures/instrumentation; Fractures; Bone/*surgery; Orthopedic Fixation Devices; Fracture Fixation – Methods
The external fixator has been in use for more than a century. Wutzer (1789-1863) used pins and an interconnecting rod-and-clamp system. Parkhill (1897) and Lambotte (1900) used devices that were unilateral with four pins and a bar-clamp system. By 1960, Vidal and Hoffmann had popularized the use of an external fixator to treat open fractures and infected pseudarthroses. The complications associated with the use of external fixation in the late 20th century were predominantly caused by a lack of understanding of the principles of application, the principles of fracture healing with external fixation, and old technology. Its use was reserved for the most severe injuries and for cases complicated by infection. Thus, pin problems, nonunions, and malunions were common. Better technology and understanding have since allowed for greater versatility and better outcomes. Simultaneous with developments in the Western world, Ilizarov developed the principles of external fixation with use of ring and wire fixation. It was not until the late 1980s and early 1990s, when more interaction and exchange between the West and East (Russia) became possible, and with the help of Italians who embraced the philosophy of external fixation, that the use of external fixation was proven to be successful. Several variations of external fixation have been developed, and its use is now widespread. However, in the United States, all but a minority of surgeons still have substantial apprehension about the use of external fixation.
Ziran Bruce H; Smith Wade R; Anglen Jeffrey O; Tornetta Iii Paul
Instructional course lectures
2008
1905-06
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.2106/00004623-200707000-00028" target="_blank" rel="noreferrer noopener">10.2106/00004623-200707000-00028</a>
Veno-venous ECMO: a synopsis of nine key potential challenges, considerations, and controversies.
Adult; Adult/*therapy; Cannulation; ECMO; Equipment Design; Extracorporeal Membrane Oxygenation/*adverse effects/instrumentation/*methods; Humans; Respiratory distress syndrome; Respiratory Distress Syndrome; Veno-venous
BACKGROUND: Following the 2009 H1N1 Influenza pandemic, extracorporeal membrane oxygenation (ECMO) emerged as a viable alternative in selected, severe cases of ARDS. Acute Respiratory Distress Syndrome (ARDS) is a major public health problem. Average medical costs for ARDS survivors on an annual basis are multiple times those dedicated to a healthy individual. Advances in medical and ventilatory management of severe lung injury and ARDS have improved outcomes in some patients, but these advances fail to consistently "rescue" a significant proportion of those affected. DISCUSSION: Here we present a synopsis of the challenges, considerations, and potential controversies regarding veno-venous ECMO that will be of benefit to anesthesiologists, surgeons, and intensivists, especially those newly confronted with care of the ECMO patient. We outline a number of points related to ECMO, particularly regarding cannulation, pump/oxygenator design, anticoagulation, and intravascular fluid management of patients. We then address these challenges/considerations/controversies in the context of their potential future implications on clinical approaches to ECMO patients, focusing on the development and advancement of standardized ECMO clinical practices. SUMMARY: Since the 2009 H1N1 pandemic ECMO has gained a wider acceptance. There are challenges that still must be overcome. Further investigations of the benefits and effects of ECMO need to be undertaken in order to facilitate the implementation of this technology on a larger scale.
Tulman David B; Stawicki Stanislaw P; Whitson Bryan A; Gupta Saarik C; Tripathi Ravi S; Firstenberg Michael S; Hayes Don Jr; Xu Xuzhong; Papadimos Thomas J
BMC anesthesiology
2014
2014
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.1186/1471-2253-14-65" target="_blank" rel="noreferrer noopener">10.1186/1471-2253-14-65</a>
Model demonstrating respiratory mechanics for high school students.
*Models; *Schools; *Teaching Materials; Adolescent; Biological; Educational; Equipment Design; Humans; Manometry; Respiratory Mechanics/*physiology
We wanted to develop educational materials appropriate for the high school student which would present physiological concepts in an innovative way. The impetus was in response to the lack of physiology educational materials appropriate for the high school level. To this end, we developed an exercise that presents the physiological basis for respiratory mechanics. The materials were designed to engage students in interactive learning and to stimulate interest for future science study. The emphasis of the exercise was the construction of a model that could be built by high school students to demonstrate respiratory mechanics. The use of models to present complex materials has been shown to be an effective medium for science learning. Our exercise contains directions for an inexpensive, easy-to-build model, as well as many supplemental teaching tools. Questions are interspersed throughout the text and at the end of the laboratory experience to facilitate the learning process. Answers are provided to the questions. Students and teachers alike are challenged to build, manipulate, and discuss their experience during the investigation of respiratory mechanics.
Chan V; Pisegna J; Rosian R; DiCarlo S E
The American journal of physiology
1996
1996-06
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.1152/advances.1996.270.6.S1" target="_blank" rel="noreferrer noopener">10.1152/advances.1996.270.6.S1</a>
Pullout strength and load to failure properties of self-tapping cortical screws in synthetic and cadaveric environments representative of healthy and osteoporotic bone.
*Bone Screws; *Bone Substitutes; *Models; *Osteoporosis; *Shear Strength; Biological; Biomechanical Phenomena; Cadaver; Equipment Design; Humans; Materials Testing/*methods; Mechanical; Stress
BACKGROUND: The parameters of self-tapping screw (STS) performance in normal and osteoporotic bone have been defined in representative environments, but the question remains as to the clinical application of such findings. The goal of this study was to analyze the biomechanical performance of STSs in cadaveric and synthetic environments representative of healthy and osteoporotic bone. METHODS: Ninety-six Synthes STSs were inserted into cadaveric and synthetic models representative of osteoporotic and healthy bone. Screws were inserted to depths of 1 mm short of the far cortex, flush and 1 mm and 2 mm beyond the far cortex. Screws were tested with an Instron 8511 material testing system utilizing axial pullout forces. A SAS procedure was used to conduct analysis of variance for unbalanced datasets. RESULTS: Substantial differences were appreciated with respect to screw performance between osteoporotic and healthy bone specimens. Although a similar pattern of increased pullout strength and loading energy with increasing depth of insertion was demonstrated, absolute values were lower in osteoporotic specimens. Although performance trends were similar in cadaveric and synthetic testing models for both osteoporotic and healthy bone, values obtained during testing were different. Incomplete insertion of STSs resulted in a 21.5% and 37% reduction of biomechanical properties in osteoporotic and normal bone, respectively. CONCLUSIONS: These results indicate that previously published findings on the performance of STSs in synthetic models cannot reasonably be applied to the clinical realm. Although trends may be similar, screw performance in synthetic, as compared with cadaveric, models is markedly different.
Schoenfeld Andrew J; Battula Suneel; Sahai Vivek; Vrabec Gregory A; Corman Steven; Burton Lyndsey; Njus Glen O
The Journal of trauma
2008
2008-05
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.1097/TA.0b013e318169cd71" target="_blank" rel="noreferrer noopener">10.1097/TA.0b013e318169cd71</a>
An operant-based detection method for inferring tinnitus in mice.
*Conditioning; *Disease Models; *Inferior colliculus; *Mouse model; *Noise-induced hearing loss; *Operant conditioning; *Sodium salicylate; *Tinnitus; Acoustic Stimulation; Analysis of Variance; Animal; Animals; Auditory; Avoidance Learning; Brain Stem/physiology; Electroshock; Equipment Design; Evoked Potentials; Female; Inbred C57BL; Inferior Colliculi/physiopathology; Male; Mice; Motor Activity; Neurons/physiology; Operant; Otoacoustic Emissions; Sodium Salicylate; Spontaneous/physiology; Tinnitus/*diagnosis/physiopathology; Tissue Culture Techniques; Voltage-Sensitive Dye Imaging
BACKGROUND: Subjective tinnitus is a hearing disorder in which a person perceives sound when no external sound is present. It can be acute or chronic. Because our current understanding of its pathology is incomplete, no effective cures have yet been established. Mouse models are useful for studying the pathophysiology of tinnitus as well as for developing therapeutic treatments. NEW METHOD: We have developed a new method for determining acute and chronic tinnitus in mice, called sound-based avoidance detection (SBAD). The SBAD method utilizes one paradigm to detect tinnitus and another paradigm to monitor possible confounding factors, such as motor impairment, loss of motivation, and deficits in learning and memory. RESULTS: The SBAD method has succeeded in monitoring both acute and chronic tinnitus in mice. Its detection ability is further validated by functional studies demonstrating an abnormal increase in neuronal activity in the inferior colliculus of mice that had previously been identified as having tinnitus by the SBAD method. COMPARISON WITH EXISTING METHODS: The SBAD method provides a new means by which investigators can detect tinnitus in a single mouse accurately and with more control over potential confounding factors than existing methods. CONCLUSION: This work establishes a new behavioral method for detecting tinnitus in mice. The detection outcome is consistent with functional validation. One key advantage of mouse models is they provide researchers the opportunity to utilize an extensive array of genetic tools. This new method could lead to a deeper understanding of the molecular pathways underlying tinnitus pathology.
Zuo Hongyan; Lei Debin; Sivaramakrishnan Shobhana; Howie Benjamin; Mulvany Jessica; Bao Jianxin
Journal of neuroscience methods
2017
2017-11
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.1016/j.jneumeth.2017.08.029" target="_blank" rel="noreferrer noopener">10.1016/j.jneumeth.2017.08.029</a>
Predictors of epinephrine autoinjector needle length inadequacy.
*Needles; Adolescence; Adolescent; Adult; Anaphylaxis – Drug Therapy; Anaphylaxis/*drug therapy; Body Mass Index; Cross Sectional Studies; Cross-Sectional Studies; Epinephrine – Administration and Dosage; Epinephrine/*administration & dosage; Equipment Design; Equipment Failure; Female; Human; Humans; Injections; Intramuscular – Equipment and Supplies; Intramuscular/instrumentation; Male; Middle Age; Middle Aged; Needles; Prospective Studies; Quadriceps Muscle/*anatomy & histology/diagnostic imaging; Quadriceps Muscles – Anatomy and Histology; Quadriceps Muscles – Ultrasonography; Sex Factors; Sympathomimetics – Administration and Dosage; Sympathomimetics/*administration & dosage; Ultrasonography; Young Adult
BACKGROUND: Self-administered epinephrine is the primary out-of-hospital treatment of anaphylaxis. Intramuscular injection of epinephrine results in higher peak plasma concentration than subcutaneous injection. With the prevalence of obesity, autoinjectors may not have an adequate needle length for intramuscular injection. OBJECTIVES: To measure muscle depth and evaluate predictors of autoinjector needle length inadequacy. METHODS: We performed a prospective cross-sectional study of a convenience sample of low acuity emergency department patients aged 18 to 55 years. We recorded demographic data, measured thigh circumference, and calculated body mass index (BMI). Using ultrasound, we took depth-to-muscle measurements of the vastus lateralus in a standing position, with and without gentle pressure to simulate muscle compression that occurs with correct autoinjector use. We conducted univariate analyses using chi(2) and t tests with P
Bhalla Mary Colleen; Gable Brad D; Frey Jennifer A; Reichenbach Matthew R; Wilber Scott T
The American journal of emergency medicine
2013
2013-12
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.1016/j.ajem.2013.09.001" target="_blank" rel="noreferrer noopener">10.1016/j.ajem.2013.09.001</a>