Search Results
Results 451 - 500 of 810
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Callaghan J P - - 2001
OBJECTIVE: To determine whether repeated motion with low magnitude joint forces, and flexion/extension moments consistently produce herniation in a non-degenerated, controlled porcine spine motion segment. DESIGN: Combined loading (flexion/extension motions and compressive forces) was applied to in vitro porcine functional spinal units. Biomechanical and radiographic characteristics were documented. BACKGROUND: While ...
Sances A A - - 2001
The anthropometric hybrid III dummy test device is the most widely used physical model to assess the injury severity during automotive crashes. The dummy was designed to replicate the human neck in flexion and frontal impacts. Various investigators have compared the dummy neck with living human and cadaveric responses in ...
Lee J - - 2001
To assess the stability of the human lumbar cadaveric spinal motion segment before and after treatment with intradiscal electrothermal therapy (IDET). An in vitro biomechanic analysis of 5 human cadaveric spinal motion segments by using nondestructive biomechanic testing in flexion/extension, lateral bending, and axial rotation with loads of 0N, 600N, ...
Fujiwara A - - 2000
STUDY DESIGN: A biomechanical and imaging study of human cadaveric spinal motion segments. OBJECTIVE: To investigate the effect of both disc degeneration and facet joint osteoarthritis on lumbar segmental motion. SUMMARY OF BACKGROUND DATA: Spinal degeneration includes the osteoarthritic changes of the facet joint as well as disc degeneration. Disc ...
Cripton P A - - 2000
Presently, there is little consensus about how, or even if, axial preload should be incorporated in spine flexibility tests in order to simulate the compressive loads naturally present in vivo. Some preload application methods are suspected of producing unwanted "artefact" forces as the specimen rotates and, in doing so, influencing ...
Aita I - - 2000
BACKGROUND: The curvature and range of motion of the cervical spine decrease after laminaplasty. However, to our knowledge these changes have not been studied prospectively. Also, the effect of laminaplasty on the mobility of the occipito-atlanto-axial joints has not been studied in detail. The purpose of our study was to ...
Lev-Tov A - - 2000
The ability of mammalian spinal cords to generate rhythmic motor patterns has been traditionally studied in hindlimb innervating segments of the spinal cord. The rhythmogenic capacity of these segments decreases substantially in the rostrocaudal direction so that the caudal lumbar segments are virtually incapable of producing the rhythm. Our recent ...
Panjabi M M - - 2000
STUDY DESIGN: An in vitro biomechanical study of lumbar spine segments. OBJECTIVE: To study the characteristics of the stiffness test protocol. SUMMARY OF BACKGROUND DATA: In an in vitro study using a flexibility protocol, forces are applied and motions are measured; no center of rotation needs to be specified. In ...
Luan F - - 2000
OBJECTIVE: To analyze neck kinematics and loading patterns during rear-end impacts. DESIGN: The motion of each cervical vertebra was captured using a 250 frame/s X-ray system during a whole body rear-end impact. These data were analyzed in order to understand different phases of neck loading during rear-end impact. BACKGROUND: The ...
Dvir Z - - 2000
OBJECTIVE: To report instrument validity of CMS 70P, a new ultrasonography-based system for spatial kinematic analysis of the spine and its application in studying the reproducibility of cervical motion findings in healthy subjects. BACKGROUND: Reproducibility of cervical motion has been investigated using various instruments and consisting in most cases of ...
Lee R Y - - 2000
OBJECTIVE: To determine the effects of the dissection of spinal tissues on the mechanical behavior of motion segments under the application of posteroanterior forces. DESIGN: A cadaveric motion segment study. SETTING: A tissue mechanics research laboratory. PROCEDURE: Anterior shear and extension moment were applied to 10 motion segments to simulate ...
Keller T S - - 2000
OBJECTIVE: The objective of this study was to quantify the mobility characteristics (dynamic stiffness and mechanical impedance) of the normal human thoracolumbar spine with a transient vibration analysis technique. DESIGN: This study is a prospective clinical investigation to obtain normative biomechanical data from the human male and female spine in ...
Mannion A F - - 2000
Range of motion tests are often employed in the quantification of musculoskeletal impairment and in the assessment of the efficacy of therapeutic interventions. The aim of the present study was to compare the absolute values for, and the day-to-day reliability of, measures of cervical spinal mobility made with two computerised ...
Vogt L - - 2000
Lumbar corsets have been recommended for low back pain patients as a way of stabilizing the lumbar region, facilitating flexion movements, and reducing pain. However, little is known about how these devices affect lumbar motion. To determine the degree of changes in the lumbar region, our approach was to quantify ...
van Poppel M N - - 2000
STUDY DESIGN: A systematic review and meta-analysis of studies on the putative mechanisms of action of lumbar supports in lifting activities. OBJECTIVE: To summarize the evidence bearing on the putative mechanisms of action of lumbar supports. SUMMARY OF BACKGROUND DATA: A restriction of trunk motion and a reduction in required ...
Harada M - - 2000
STUDY DESIGN: Motion characteristics of the lumbar spine in the sagittal plane were investigated in vivo using cineradiography. OBJECTIVES: To evaluate the differences in motion characteristics of the normal lumbar spine between forward and backward flexion. SUMMARY OF BACKGROUND DATA: Despite previous lumbar kinematic studies, differences in motion characteristics of ...
Wang J L - - 2000
STUDY DESIGN: The role of bone graft force in stabilizing an instrumented cervical spine was evaluated for one-level and three-level corpectomy models using in vitro experiments. OBJECTIVES: To investigate the role of bone graft force in enhancing stability of anterior cervical plate, and to study effects of fatigue loading. SUMMARY ...
Harrison D E - - 2000
OBJECTIVE: To determine cervical coupling during the posture of lateral head translation relative to a fixed thoracic cage. DESIGN: Digitized measurements from anteroposterior cervical radiographs of 20 volunteers were obtained in neutral, left, and right lateral translation posture of the head compared to a fixed thorax. BACKGROUND DATA: Clinically, lateral ...
Adams M A - - 2000
STUDY DESIGN: Mechanical testing of cadaveric lumbar motion segments. OBJECTIVES: To test the hypothesis that minor damage to a vertebral body can lead to progressive disruption of the adjacent intervertebral disc. SUMMARY OF BACKGROUND DATA: Disc degeneration involves gross structural disruption as well as cell-mediated changes in matrix composition, but ...
Granata K P - - 2000
STUDY DESIGN: Low back kinematics, including relative lumbar and pelvic motions, were quantified during controlled lifting tasks. OBJECTIVES: To evaluate the influence of load and lifting velocity on lumbar-pelvic (LP) coordination. SUMMARY OF BACKGROUND DATA: Sagittal trunk extension is achieved through the coordinated motion of the pelvis and lumbar spine. ...
Lengsfeld M - - 2000
OBJECTIVE: To measure load and moment changes acting on the lumbar spine during rotatory sitting. BACKGROUND: A new chair concept generating dynamic stimuli by alternating rotations in the horizontal plane of the chair's seat was recently developed. METHODS: Load and moment changes were measured telemetrically with a spinal fixator device ...
Petersen C M - - 2000
Cervical range of motion (ROM) is evaluated in both clinical and research settings. This study's purpose was to determine if ROM data obtained with the OSI CA 6000 Spine Motion Analyser (SMA) from asymptomatic and symptomatic cervical subjects were reliable within and between testers. Cervical ROM was measured in all ...
Mannion A F - - 2000
STUDY DESIGN: A cross-sectional study of spinal loading in healthy volunteers. OBJECTIVES: To measure the bending and compressive forces acting on the lumbar spine, in a range of postures, when unknown loads are delivered unexpectedly to the hands. SUMMARY OF BACKGROUND DATA: Epidemiologic studies suggest that sudden and unexpected loading ...
Lennarson P J - - 2000
OBJECT: The purpose of this study was to establish a cadaveric model for evaluating cervical spine motion in both the intact and injured states and to examine the efficacy of commonly used stabilization techniques in limiting that motion. METHODS: Intubation was performed in fresh human cadavers with intact cervical spines, ...
Miyasaka K - - 2000
STUDY DESIGN: This in vivo study was performed to examine active lumbar motion without any support. OBJECTIVES: To establish the behavior of segmental flexibility according to the degree of whole lumbar motion and to clarify the correlation between bony characteristics of the lumbosacral junction and stability in the segment. SUMMARY ...
Adams M A - - 2000
STUDY DESIGN: Mechanical testing of cadaveric motion segments. OBJECTIVES: To test the hypothesis that backward bending of the lumbar spine can reduce compressive stresses within lumbar intervertebral discs. SUMMARY OF BACKGROUND DATA: Lumbar extension affects the distribution of compressive stress inside normal cadaveric discs, but little is known about its ...
van Deursen D L - - 2000
Changes in spinal length were used to evaluate a new concept for an office chair. This so-called dynamic chair imparts passive forced motion to the seated subject. The passive forced motion is a rotary movement about an axis, perpendicular to the seat with amplitude of 0.6 degrees and a frequency ...
Tousignant M - - 2000
STUDY DESIGN: This study used a validity protocol. OBJECTIVE: To estimate the criterion validity of the Cervical Range of Motion goniometer using a healthy population. SUMMARY OF BACKGROUND DATA: The results of the 1994 study by Mayo et al show that there are no validated tools currently available for clinically ...
Solinger A B - - 2000
OBJECT: Develop an analytical theory describing the dynamics of small impulses applied to vertebrae, such as in chiropractic adjustments or spinal manipulative therapy. DESIGN: Data were compared with damped harmonic oscillator models of vertebrae. BACKGROUND: Evidence accumulates that chiropractic adjustments are effective in addressing a variety of health problems. However, ...
Ransone J - - 2000
OBJECTIVE: To determine the effectiveness of the Rapid Form Cervical Vacuum Immobilizer in controlling the cervical spine movements of a football player wearing shoulder pads and a helmet. DESIGN AND SETTING: We used a 1-group, repeated-measures experimental design to radiographically assess cervical spine range of motion with and without the ...
Miller W L - - 2000
Timing of oscillatory activity along the longitudinal body axis is critical for locomotion in the lamprey and other elongated animals. In the lamprey spinal locomotor central pattern generator (CPG), intersegmental coordination is thought to arise from the pattern of extensive connections made by propriospinal interneurons. However, the mechanisms responsible for ...
Nussbaum M A - - 1999
Although often suggested as a control measure to alleviate musculoskeletal stresses, the use of mechanical assistance devices (i.e. manipulators) in load transfers has not been extensively studied. Without data describing the biomechanical effects of such devices, justification for decisions regarding implementation of such tools is difficult. An experimental study of ...
Martin-Hirsch P - - 1999
BACKGROUND: Few randomised controlled trials have sufficient power to show clear advantages of different designs of cervical-smear collection devices. We studied by systematic review whether the design of cervical-smear devices affects rates of inadequate smears and detection of disease and whether the presence of endocervical cells in the smear affects ...
Panjabi M M - - 1999
STUDY DESIGN: An in vitro biomechanical study of one-level and three-level corpectomy and anterior cervical plate models. OBJECTIVE: To investigate the failure of the screw-vertebra interfaces in one- and three-level corpectomy models. SUMMARY AND BACKGROUND DATA: Although there are several biomechanical studies of strength and stability of anterior cervical plating, ...
Scifert J L - - 1999
STUDY DESIGN: An in vitro test of calf spine lumbar segments to compare biomechanical stabilization of a rigid versus a dynamic posterior fixation device. OBJECTIVES: To compare flexibility of a dynamic pedicle screw fixation device with an equivalent rigid device. SUMMARY OF BACKGROUND DATA: Dynamic pedicle screw device studies are ...
Mannion A - - 1999
OBJECTIVE. The aim of the study was to compare lumbar range of motion determined using two computerised dynamic motion analysis devices. BACKGROUND: Measures of spinal motion are currently used in biomechanical, epidemiological and clinical studies of the low back. It is essential that the various devices used to measure mobility ...
Yamabe Y - - 1999
Several studies have examined the functional relationship between mandibular movement and head or body posture, but head and body motion during jaw movement have not been extensively investigated. Ten healthy participants performed repetitive jaw tapping movement. Piezoelectric accelerometers were attached on the surfaces of the participant's forehead, mentum, and over ...
Isomi T - - 1999
STUDY DESIGN: An in vitro investigation of three-dimensional kinematics of cervical spine models of one- and three-level corpectomy with anterior plate fixation. OBJECTIVES: To evaluate the capability of an anterior plate to stabilize the reconstructed cervical spine under simulated physiologic motions, and to study the effects of fatigue loading. SUMMARY ...
Harrison D D - - 1999
OBJECTIVE: To develop a new sitting spinal model and an optimal driver's seat by using review of the literature of seated positions of the head. spine, pelvis, and lower extremities. DATA SELECTION: Searches included MEDLINE for scientific journals, engineering standards, and textbooks. Key terms included sitting ergonomics, sitting posture, spine ...
Oda I - - 1999
STUDY DESIGN: In an in vivo sheep model, the effects of spinal fusion and kyphotic deformity on the neighboring motion segments were analyzed. OBJECTIVES: To investigate the effects of spinal fusion and kyphotic deformity on the adjacent motion segment. SUMMARY OF BACKGROUND DATA: The in vivo effects of kyphotic deformity ...
Vicenzino B - - 1999
OBJECTIVE: To investigate the specificity of linear and angular displacement, peak velocity and frequency of oscillation of the frontal plane motion produced by the lateral glide treatment technique of the cervical spine. DESIGN: A within-subjects design was used. BACKGROUND: The lateral glide treatment technique of the cervical spine has previously ...
Sahni I K - - 1999
STUDY DESIGN: Direct measurement of intervertebral motion was compared to motion determined by measuring the position of the exposed ends of the external fixation pins. OBJECTIVES: To verify the accuracy of this technique, so that this protocol can be used to study intervertebral motion in the clinical setting. SUMMARY OF ...
Natarajan R N - - 1999
STUDY DESIGN: The influence of lumbar disc height and cross-sectional area on the mechanical response of the disc to physiologic loading was determined using a finite element model. OBJECTIVES: To identify which geometric characteristics are potentially related to motion segment mechanical response to applied load, such as flexibility, fiber stress, ...
Feipel V - - 1999
OBJECTIVE: Establishment of a normal database and clinical reference of active global cervical spine motion ranges and patterns using a commercial electrogoniometer. DESIGN: Three-dimensional cervical motion ranges and patterns were analyzed in 250 asymptomatic volunteers. BACKGROUND: In vivo out-of-plane motion patterns of the cervical spine have not yet been reported ...
Madson T J - - 1999
STUDY DESIGN: Single-group repeated measures for single rater reliability. OBJECTIVES: To describe the intratester reliability for measurements of active lumbar spine mobility and pelvic inclination during standing obtained with the back range-of-motion (BROM) device. BACKGROUND: The BROM device has often been used to quantify lumbar spine active range of motion. ...
Pickar J G - - 1999
This paper describes a method for applying controlled loads to a lumbar vertebra while recording in vivo from primary afferents innervating the lumbar paraspinal tissues. Unlike the appendicular skeleton, the vertebral column poses a unique challenge for neurophysiological investigations. Distances between paraspinal tissues and the spinal cord are short. In ...
Gatton M L - - 1999
OBJECTIVES: This study investigated the sequence of intervertebral joint movements and range of motion during three tasks involving lumbar flexion. DESIGN: Position sensors were used to measure position and rotation of lumbar vertebrae during unconstrained flexion. BACKGROUND: In the development of mathematical models, numerous assumptions need to be made. Few ...
McGorry R W - - 1999
STUDY DESIGN: Relative phase angle was used to study segmental motion patterns during a lifting and lowering task. OBJECTIVES: To investigate the effect of back belts, breathing technique, and their interaction on lumbar and pelvic motion patterns. SUMMARY OF BACKGROUND DATA: Trunk and pelvic coordination has been investigated in healthy ...
Lantz C A - - 1999
STUDY DESIGN: A study of inter- and intra-examiner reliability and clinical validity using two instruments for assessment of spinal range of motion in healthy individuals. OBJECTIVE: To assess the clinical validity, stability, and normative values for active and passive cervical range of motion as measured by the CA-6000 (Orthopedic Systems ...
Macy N B - - 1999
To determine the effect that ventral intervertebral disk fenestration has on the sagittal range of motion about the C5-C6 intervertebral space. A repeated measures in vitro mechanical study of spinal range of motion under controlled loading conditions before and after fenestration. A total of 10 canine cervical vertebral specimens (C4-C7) ...
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