The Experts below are selected from a list of 6483 Experts worldwide ranked by ideXlab platform
S Young - One of the best experts on this subject based on the ideXlab platform.
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the clinical relevance of sound changes produced during cementless hip arthroplasty a correctly sized femoral broach creates a distinctive pattern of Audio Frequencies directly related to bone geometry
2018Co-Authors: J Mcconnell, P R J Saunders, S YoungAbstract:Aims Cementless femoral stems must be correctly sized and well-seated to obtain satisfactory biological fixation. The change in sound that occurs during impaction of the femoral broach is said to i...
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good vibrations a correctly sized femoral broach creates a distinctive pattern of Audio Frequencies directly related to bone geometry
2018Co-Authors: J Mcconnell, S YoungAbstract:When inserting a femoral stem, surgeons make use of many visual and tactile cues to be sure that the implant is correctly sized and well-seated. One such cue is the change of pitch that can be hear...
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good vibrations a correctly sized femoral broach creates a distinctive pattern of Audio Frequencies directly related to bone geometry
2017Co-Authors: J Mcconnell, S YoungAbstract:When inserting a femoral stem, surgeons make use of many visual and tactile cues to be sure that the implant is correctly sized and well-seated. One such cue is the change of pitch that can be heard when the final femoral broach is inserted. This is known to be important, but has not been widely studied. We set out to analyse the sounds produced during femoral broaching and implant fixation, and to discover whether the absence of these sounds could predict a poor fixation. We recorded the sound of femoral broaching and definitive implant insertion, for twenty un-cemented Corail total hip replacements. Procedures were performed by the same surgeon, in the same theatre. The recordings were visualised using Audio editing software, and a Fast Fourier Transform was used to identify the dominant Audio Frequencies. In 19 of the 20 cases, the final strikes of the final femoral broach displayed a distinctive pattern, with the most prominent Frequencies being harmonics (multiples of a fundamental frequency) which had a wavelength directly related to the length of the femoral canal. This contrasts with initial strikes, where multiple unrelated Frequencies were present. Postoperative radiographs were examined by two surgeons independently, to assess implant sizing and positioning. The one case, in which the harmonic pattern was not observed, was found on radiographs to be an undersized, varus malpositioned implant. We demonstrate that a characteristic frequency pattern is present when impacting cancellous bone with a well-sized and well-placed femoral broach. When the pattern was absent, the broach and implant were undersized and malpositioned. We hypothesise that this pattern arises when broach and femur are vibrating as one, indicating adequate contact with, and compression of, cancellous bone.
J Mcconnell - One of the best experts on this subject based on the ideXlab platform.
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the clinical relevance of sound changes produced during cementless hip arthroplasty a correctly sized femoral broach creates a distinctive pattern of Audio Frequencies directly related to bone geometry
2018Co-Authors: J Mcconnell, P R J Saunders, S YoungAbstract:Aims Cementless femoral stems must be correctly sized and well-seated to obtain satisfactory biological fixation. The change in sound that occurs during impaction of the femoral broach is said to i...
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good vibrations a correctly sized femoral broach creates a distinctive pattern of Audio Frequencies directly related to bone geometry
2018Co-Authors: J Mcconnell, S YoungAbstract:When inserting a femoral stem, surgeons make use of many visual and tactile cues to be sure that the implant is correctly sized and well-seated. One such cue is the change of pitch that can be hear...
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good vibrations a correctly sized femoral broach creates a distinctive pattern of Audio Frequencies directly related to bone geometry
2017Co-Authors: J Mcconnell, S YoungAbstract:When inserting a femoral stem, surgeons make use of many visual and tactile cues to be sure that the implant is correctly sized and well-seated. One such cue is the change of pitch that can be heard when the final femoral broach is inserted. This is known to be important, but has not been widely studied. We set out to analyse the sounds produced during femoral broaching and implant fixation, and to discover whether the absence of these sounds could predict a poor fixation. We recorded the sound of femoral broaching and definitive implant insertion, for twenty un-cemented Corail total hip replacements. Procedures were performed by the same surgeon, in the same theatre. The recordings were visualised using Audio editing software, and a Fast Fourier Transform was used to identify the dominant Audio Frequencies. In 19 of the 20 cases, the final strikes of the final femoral broach displayed a distinctive pattern, with the most prominent Frequencies being harmonics (multiples of a fundamental frequency) which had a wavelength directly related to the length of the femoral canal. This contrasts with initial strikes, where multiple unrelated Frequencies were present. Postoperative radiographs were examined by two surgeons independently, to assess implant sizing and positioning. The one case, in which the harmonic pattern was not observed, was found on radiographs to be an undersized, varus malpositioned implant. We demonstrate that a characteristic frequency pattern is present when impacting cancellous bone with a well-sized and well-placed femoral broach. When the pattern was absent, the broach and implant were undersized and malpositioned. We hypothesise that this pattern arises when broach and femur are vibrating as one, indicating adequate contact with, and compression of, cancellous bone.
Ingo R. Titze - One of the best experts on this subject based on the ideXlab platform.
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viscoelastic properties of three vocal fold injectable biomaterials at low Audio Frequencies
2004Co-Authors: Sarah A. Klemuk, Ingo R. TitzeAbstract:Objectives: Previous measurements of viscoelastic properties of Zyderm were to be extended to low Audio Frequencies, and properties of two other biomaterials not previously measured, thiolated hyaluronic acid (HA-DTPH) and Cymetra, were obtained. Study Design: Rheologic investigation. Methods: Oscillatory shear stress was applied to each sample using a controlled stress rheometer at Frequencies between 0.01 and 100 Hz with a parallel plate apparatus. Versuscoelastic moduli were recorded at each frequency. The calculated resonance frequency of the machine and sample were then used to determine the maximum frequency at which reliable data existed. Extrapolation functions were fit to viscoelastic parameters, which predicted the properties up to 1,000 Hz. Results: Frequency trends of Zyderm were similar to those previously reported, whereas magnitudes were different. The elastic moduli logarithmically increased with frequency, whereas dynamic viscosity demonstrated shear thinning, a condition of primary importance for humans to vocalize over a broad frequency range. Previous measurements were extended from 15 Hz up to 74 Hz. Differences in magnitude between a previous study and the present study were attributed to particulate orientation during testing. Cymetra was found to have nearly identical viscoelastic properties to those of bovine collagen, both in magnitude and frequency trend, with reliable measures extending up to 81 Hz. Rheologic properties of the hyaluronic acid gel were the closest match to cadaveric vocal fold mucosa in magnitude and frequency trend. Conclusions: Viscoelastic properties of Cymetra and Zyderm are nearly the same and are significantly greater than those of vocal fold mucosa. HA-DTPH possesses a good viscoelastic match to vocal fold mucosa and may be useful in future lamina propria repair.
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Methodology for rheological testing of engineered biomaterials at low Audio Frequencies.
2004Co-Authors: Ingo R. Titze, Sarah A. Klemuk, Steven D. GrayAbstract:A commercial rheometer (Bohlin CVO120) was used to mechanically test materials that approximate vocal-fold tissues. Application is to Frequencies in the low Audio range (20–150 Hz). Because commercial rheometers are not specifically designed for this frequency range, a primary problem is maintaining accuracy up to (and beyond) the mechanical resonance frequency of the rotating shaft assembly. A standard viscoelastic material (NIST SRM 2490) has been used to calibrate the rheometric system for an expanded frequency range. Mathematically predicted response curves are compared to measured response curves, and an error analysis is conducted to determine the accuracy to which the elastic modulus and the shear modulus can be determined in the 20–150-Hz region. Results indicate that the inertia of the rotating assembly and the gap between the plates need to be known (or determined empirically) to a high precision when the measurement frequency exceeds the resonant frequency. In addition, a phase correction is needed to account for the magnetic inertia (inductance) of the drag cup motor. Uncorrected, the measured phase can go below the theoretical limit of −π. This can produce large errors in the viscous modulus near and above the resonance frequency. With appropriate inertia and phase corrections, ±10% accuracy can be obtained up to twice the resonance frequency.
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methodology for straining engineered vocal fold tissues at Audio Frequencies
2001Co-Authors: Sarah A. Klemuk, Ingo R. Titze, Steven D. GrayAbstract:Engineered vocal fold tissues will be grown under conditions of shear strain, the magnitude of which is determined by known strains during human vocal fold oscillation. A cup and plate system is used with the Bohlin CVO 120 rheometer to apply a shear strain of approximately 0.4 radians at Frequencies of 20–60 Hz. Baseline viscoelastic measurements are recorded for the synthetic scaffolding material into which different cell lines will be injected and grown to form their own matrix. The methodology allows duration and repetitions of strain exposure to seeded scaffolding to be varied and for subsequent viscoelastic measurements to be compared. [Work supported by NIDCD.]
Sarah A. Klemuk - One of the best experts on this subject based on the ideXlab platform.
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viscoelastic properties of three vocal fold injectable biomaterials at low Audio Frequencies
2004Co-Authors: Sarah A. Klemuk, Ingo R. TitzeAbstract:Objectives: Previous measurements of viscoelastic properties of Zyderm were to be extended to low Audio Frequencies, and properties of two other biomaterials not previously measured, thiolated hyaluronic acid (HA-DTPH) and Cymetra, were obtained. Study Design: Rheologic investigation. Methods: Oscillatory shear stress was applied to each sample using a controlled stress rheometer at Frequencies between 0.01 and 100 Hz with a parallel plate apparatus. Versuscoelastic moduli were recorded at each frequency. The calculated resonance frequency of the machine and sample were then used to determine the maximum frequency at which reliable data existed. Extrapolation functions were fit to viscoelastic parameters, which predicted the properties up to 1,000 Hz. Results: Frequency trends of Zyderm were similar to those previously reported, whereas magnitudes were different. The elastic moduli logarithmically increased with frequency, whereas dynamic viscosity demonstrated shear thinning, a condition of primary importance for humans to vocalize over a broad frequency range. Previous measurements were extended from 15 Hz up to 74 Hz. Differences in magnitude between a previous study and the present study were attributed to particulate orientation during testing. Cymetra was found to have nearly identical viscoelastic properties to those of bovine collagen, both in magnitude and frequency trend, with reliable measures extending up to 81 Hz. Rheologic properties of the hyaluronic acid gel were the closest match to cadaveric vocal fold mucosa in magnitude and frequency trend. Conclusions: Viscoelastic properties of Cymetra and Zyderm are nearly the same and are significantly greater than those of vocal fold mucosa. HA-DTPH possesses a good viscoelastic match to vocal fold mucosa and may be useful in future lamina propria repair.
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Methodology for rheological testing of engineered biomaterials at low Audio Frequencies.
2004Co-Authors: Ingo R. Titze, Sarah A. Klemuk, Steven D. GrayAbstract:A commercial rheometer (Bohlin CVO120) was used to mechanically test materials that approximate vocal-fold tissues. Application is to Frequencies in the low Audio range (20–150 Hz). Because commercial rheometers are not specifically designed for this frequency range, a primary problem is maintaining accuracy up to (and beyond) the mechanical resonance frequency of the rotating shaft assembly. A standard viscoelastic material (NIST SRM 2490) has been used to calibrate the rheometric system for an expanded frequency range. Mathematically predicted response curves are compared to measured response curves, and an error analysis is conducted to determine the accuracy to which the elastic modulus and the shear modulus can be determined in the 20–150-Hz region. Results indicate that the inertia of the rotating assembly and the gap between the plates need to be known (or determined empirically) to a high precision when the measurement frequency exceeds the resonant frequency. In addition, a phase correction is needed to account for the magnetic inertia (inductance) of the drag cup motor. Uncorrected, the measured phase can go below the theoretical limit of −π. This can produce large errors in the viscous modulus near and above the resonance frequency. With appropriate inertia and phase corrections, ±10% accuracy can be obtained up to twice the resonance frequency.
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methodology for straining engineered vocal fold tissues at Audio Frequencies
2001Co-Authors: Sarah A. Klemuk, Ingo R. Titze, Steven D. GrayAbstract:Engineered vocal fold tissues will be grown under conditions of shear strain, the magnitude of which is determined by known strains during human vocal fold oscillation. A cup and plate system is used with the Bohlin CVO 120 rheometer to apply a shear strain of approximately 0.4 radians at Frequencies of 20–60 Hz. Baseline viscoelastic measurements are recorded for the synthetic scaffolding material into which different cell lines will be injected and grown to form their own matrix. The methodology allows duration and repetitions of strain exposure to seeded scaffolding to be varied and for subsequent viscoelastic measurements to be compared. [Work supported by NIDCD.]
Paul J Remington - One of the best experts on this subject based on the ideXlab platform.
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structure borne sound structural vibrations and sound radiation at Audio Frequencies 3rd edition
2005Co-Authors: Paul J RemingtonAbstract:This article reviews Structure-Borne Sound: Structural Vibrations and Sound Radiation at Audio Frequencies (3rd Edition) by L. Cremer, M. Heckl, B. A. T. Petersson , Berlin, 2005. 607 pp. Price: $199.00 (hardcover), ISBN: 3540226966.
