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PubMed2001

Control of microtubule dynamics by Stu2p is essential for spindle orientation and metaphase chromosome alignment in yeast.

Stu2p is a member of a conserved family of microtubule-binding proteins and an essential protein in yeast. Here, we report the first in vivo analysis of microtubule dynamics in cells lacking a member of this protein family. For these studies, we have used a conditional Stu2p depletion strain expressing alpha-tubulin fused to green fluorescent protein. Depletion of Stu2p leads to fewer and less dynamic cytoplasmic microtubules in both G1 and preanaphase cells. The reduction in cytoplasmic microtubule dynamics is due primarily to decreases in both the catastrophe and rescue frequencies and an increase in the fraction of time microtubules spend pausing. These changes have significant consequences for the cell because they impede the ability of cytoplasmic microtubules to orient the spindle. In addition, recovery of fluorescence after photobleaching indicates that kinetochore microtubules are no longer dynamic in the absence of Stu2p. This deficiency is correlated with a failure to properly align chromosomes at metaphase. Overall, we provide evidence that Stu2p promotes the dynamics of microtubule plus-ends in vivo and that these dynamics are critical for microtubule interactions with kinetochores and cortical sites in the cytoplasm.

Animals↗
PubMed2003

Yeast kinetochores do not stabilize Stu2p-dependent spindle microtubule dynamics.

The interaction of kinetochores with dynamic microtubules during mitosis is essential for proper centromere motility, congression to the metaphase plate, and subsequent anaphase chromosome segregation. Budding yeast has been critical in the discovery of proteins necessary for this interaction. However, the molecular mechanism for microtubule-kinetochore interactions remains poorly understood. Using live cell imaging and mutations affecting microtubule binding proteins and kinetochore function, we identify a regulatory mechanism for spindle microtubule dynamics involving Stu2p and the core kinetochore component, Ndc10p. Depleting cells of the microtubule binding protein Stu2p reduces kinetochore microtubule dynamics. Centromeres remain under tension but lack motility. Thus, normal microtubule dynamics are not required to maintain tension at the centromere. Loss of the kinetochore (ndc10-1, ndc10-2, and ctf13-30) does not drastically affect spindle microtubule turnover, indicating that Stu2p, not the kinetochore, is the foremost governor of microtubule dynamics. Disruption of kinetochore function with ndc10-1 does not affect the decrease in microtubule turnover in stu2 mutants, suggesting that the kinetochore is not required for microtubule stabilization. Remarkably, a partial kinetochore defect (ndc10-2) suppresses the decreased spindle microtubule turnover in the absence of Stu2p. These results indicate that Stu2p and Ndc10p differentially function in controlling kinetochore microtubule dynamics necessary for centromere movements.

Benomyl↗
PubMed2005

Induction of cytokinesis is independent of precisely regulated microtubule dynamics.

Astral microtubules (MTs) emanating from the mitotic apparatus (MA) during anaphase are required for stimulation of cytokinesis in eggs. We have used green fluorescent protein-labeled EB1 to observe MT dynamics during mitosis and cytokinesis in normal sea urchin eggs. Analysis of astral MT growth rates during anaphase shows that MTs contact the polar cortex earlier than the equatorial cortex after anaphase onset but that a normal cleavage furrow is not induced until contact with MTs has been achieved throughout the cortex. To assess the role of MT dynamics in initiation of cytokinesis, we used a collection of small molecule drugs to affect dynamics. Hexylene glycol resulted in rapid astral elongation due to decreased MT catastrophe and precocious furrowing. Taxol suppressed MT dynamics but did not inhibit furrow induction when the MA was manipulated toward the cortex. Urethane resulted in short, highly dynamic astral MTs with increased catastrophe that also stimulated furrowing upon being brought into proximity to the cortex. Our findings indicate that astral MT contact with the cortex is necessary for furrow initiation but that the dynamic state of astral MTs does not affect their competency to stimulate furrowing.

Anaphase↗
PubMed2006

TESD: a transposable element dynamics simulation environment.

UNLABELLED: Various mathematical models have been used to explore the dynamics of transposable elements (TEs) within their host genomes. However, numerous factors can influence their dynamics, and we know only little about the dynamics of TEs when they first began to invade populations. In addition, the influence of population structuring has only recently been investigated. Transposable Element Simulator Dynamics, a population genomics simulation environment, has therefore been developed to provide a simple tool for analyzing the dynamics of TEs in a community based on (i) various TE parameters, such as the transposition and excision rates, the recombination rate and the coefficient of selection against TE insertions; and (ii) population parameters, such as population size and migration rates. The simulations can be used to illustrate the dynamic fate of TEs in structured populations, can be extended by using more specific molecular or demographic models, and can be useful for teaching population genetics and genomics. AVAILABILITY: TESD is distributed under GPL from the Pôle Bioinformatique Lyonnais (PBIL) web server at http://pbil.univ-lyon1.fr/software/TESD

Algorithms↗
PubMed2004

Dynamic computed tomography and color Doppler ultrasound of renal parenchymal neoplasms: correlations with histopathological findings.

BACKGROUND: We evaluated whether color Doppler ultrasound (US) had diagnostic accuracy equal to dynamic computed tomography (CT) and whether performing dynamic CT and Doppler US together would be more informative in preoperative diagnosis of renal solid tumors. METHODS: A total of 110 renal solid tumors smaller than 7 cm were evaluated with dynamic CT and Doppler US. We compared the enhancement and the color flow patterns with the histopathological subtypes. RESULTS: Eighty-seven (95.6%) of 91 clear cell carcinomas showed rich enhancement in the cortical nephrographic phase (CNP) and 82 (90.1%) of them had color flow in the Doppler US. Of the total of 110 tumors, nine (8.1%) did not show color flow in spite of rich enhancement in the CNP. Conversely, eight (7.2%) of the 110 tumors showed color flow in spite of poor enhancement, including two chromophobe cell carcinomas and two metastatic renal tumors. CONCLUSIONS: The enhancement pattern in dynamic CT and the color flow pattern in Doppler US were different among the subtypes of RCC. Color Doppler US had diagnostic accuracy equal to dynamic CT in most patients with renal solid tumors. Although Doppler US may play a unique role in the diagnosis of some renal parenchymal solid tumors, it is sufficient to perform dynamic CT alone for diagnosis of clear cell carcinoma.

Adenocarcinoma, Clear Cell↗
PubMed2004

Dynamic testing in schizophrenia: does training change the construct validity of a test?

Dynamic testing typically involves specific interventions for a test to assess the extent to which test performance can be modified, beyond level of baseline (static) performance. This study used a dynamic version of the Wisconsin Card Sorting Test (WCST) that is based on cognitive remediation techniques within a test-training-test procedure. From results of previous studies with schizophrenia patients, we concluded that the dynamic and static versions of the WCST should have different construct validity. This hypothesis was tested by examining the patterns of correlations with measures of executive functioning, secondary verbal memory, and verbal intelligence. Results demonstrated a specific construct validity of WCST dynamic (i.e., posttest) scores as an index of problem solving (Tower of Hanoi) and secondary verbal memory and learning (Auditory Verbal Learning Test), whereas the impact of general verbal capacity and selective attention (Verbal IQ, Stroop Test) was reduced. It is concluded that the construct validity of the test changes with dynamic administration and that this difference helps to explain why the dynamic version of the WCST predicts functional outcome better than the static version.

Cognition Disorders↗
PubMed1998

Dynamic exercise therapy in rheumatoid arthritis: a systematic review.

The aim of this systematic review was to determine the effectiveness of dynamic exercise therapy in improving joint mobility, muscle strength, aerobic capacity and daily functioning in patients with rheumatoid arthritis (RA). In addition, possible unwanted effects such as an increase in pain, disease activity and radiological progression were studied. A computer-aided search of the MEDLINE, Embase and SCISEARCH databases was performed to identify controlled trials on the effect of exercise therapy. Randomized trials were selected on the effect of dynamic exercise therapy in RA patients with an exercise programme fulfilling the following criteria: (a) intensity level such that heart rates exceeded 60% of maximal heart rate during at least 20 min; (b) exercise frequency > or = 2 a week; and (c) duration of intervention > or = 6 weeks. Two blinded reviewers independently selected eligible studies, rated the methodological quality and extracted data. Six out of 30 identified controlled trials met the inclusion criteria. Four of the six included studies fulfilled > or = 7/10 methodological criteria. Because of heterogeneity in outcome measures, data could not be pooled. The results suggest that dynamic exercise therapy is effective in increasing aerobic capacity and muscle strength. No detrimental effects on disease activity and pain were observed. The effects of dynamic exercise therapy on functional ability and radiological progression are unclear. It is concluded that dynamic exercise therapy has a positive effect on physical capacity. Research on the long-term effect of dynamic exercise therapy on radiological progression and functional ability is needed.

Activities of Daily Living↗
PubMed2002

Short-term light and leaf photosynthetic dynamics affect estimates of daily understory photosynthesis in four tree species.

Instantaneous measurements of photosynthesis are often implicitly or explicitly scaled to longer time frames to provide an understanding of plant performance in a given environment. For plants growing in a forest understory, results from photosynthetic light response curves in conjunction with diurnal light data are frequently extrapolated to daily photosynthesis (A(day)), ignoring dynamic photosynthetic responses to light. In this study, we evaluated the importance of two factors on A(day) estimates: dynamic physiological responses to photosynthetic photon flux density (PPFD); and time-resolution of the PPFD data used for modeling. We used a dynamic photosynthesis model to investigate how these factors interact with species-specific photosynthetic traits, forest type, and sky conditions to affect the accuracy of A(day) predictions. Increasing time-averaging of PPFD significantly increased the relative overestimation of A(day) similarly for all study species because of the nonlinear response of photosynthesis to PPFD (15% with 5-min PPFD means). Depending on the light environment characteristics and species-specific dynamic responses to PPFD, understory tree A(day) can be overestimated by 6-42% for the study species by ignoring these dynamics. Although these overestimates decrease under cloudy conditions where direct sunlight and consequently understory sunfleck radiation is reduced, they are still significant. Within a species, overestimation of A(day) as a result of ignoring dynamic responses was highly dependent on daily sunfleck PPFD and the frequency and irradiance of sunflecks. Overall, large overestimates of A(day) in understory trees may cause misleading inferences concerning species growth and competition in forest understories with < 2% full sunlight. We conclude that comparisons of A(day) among co-occurring understory species in deep shade will be enhanced by consideration of sunflecks by using high-resolution PPFD data and understanding the physiological responses to sunfleck variation.

Acer↗
PubMed1999

Dynamic cerebral autoregulation during sevoflurane anesthesia: a comparison with isoflurane.

UNLABELLED: We investigated dynamic cerebral pressure autoregulation awake and during 1.5 minimum alveolar anesthetic concentration (MAC) sevoflurane or isoflurane anesthesia in 16 patients undergoing nonintracranial neurosurgical procedures. All patients received a standardized anesthetic, and their lungs were ventilated with 1.5 MAC volatile anesthetic in 100% oxygen to normocapnia. Routine monitors included electrocardiogram, pulse oximetry, end-tidal capnography, and continuous noninvasive blood pressure. In addition, middle cerebral artery blood velocity (Vmca) was measured continuously using transcranial Doppler ultrasonography. Dynamic cerebral autoregulation was tested by inducing a rapid transient decrease in mean arterial pressure by deflation of large thigh cuffs, which were placed around both thighs and inflated to 100 mm Hg above systolic pressure. The Vmca response to the decrease in blood pressure was fitted to a series of curves to determine the rate of dynamic cerebral autoregulation (dRoR). Awake dRoR values were similar in the isoflurane and sevoflurane groups, 32 +/- 2%/s and 29 +/- 2%/s, respectively. dRoR decreased to 5 +/- 1%/s during isoflurane anesthesia but to only 24 +/- 2%/s during sevoflurane anesthesia. We conclude that dynamic cerebral autoregulation is better preserved during sevoflurane than isoflurane anesthesia in humans. IMPLICATIONS: We investigated the effect of sevoflurane and isoflurane on dynamic cerebral pressure autoregulation using transcranial Doppler ultrasonography. At 1.5 minimum alveolar anesthetic concentration, dynamic autoregulation was better preserved during sevoflurane than isoflurane anesthesia.

Adult↗
PubMed2002

Dynamic glenohumeral stability provided by three heads of the deltoid muscle.

The deltoid is a large bulky muscle, comprising approximately 20% of the shoulder muscles. Therefore, the function of the deltoid as a stabilizer is thought to be significant. The current authors quantified dynamic glenohumeral stability provided by three heads of the deltoid by a new biomechanical parameter, the dynamic stability index. The dynamic stability index considers not only the force vectors generated by individual shoulder muscle, but also the concavity compression mechanism. The higher the dynamic stability index, the greater the dynamic stability. The deltoid generated significant shear force and compressive force in the position of anterior shoulder instability. The deltoid provided dynamic stability with the arm in the scapular plane and only decreased the stability of the shoulder with the arm in the coronal plane. The mid and posterior heads should be strengthened vigorously in anterior shoulder instability in conservative and operative treatment, because they provide more stability generating higher compressive force and lower shear force than the anterior head. Scapular muscles should be balanced to avoid the vulnerable glenohumeral position where the arm is extended beyond the scapular plane. Anatomic reattachment of the detached labrum onto the glenoid rim in the anterior instability is important to enhance the effect of compressive force component generated by the muscles.

Aged↗
PubMed1990

Effects of dynamization after interlocking tibial nailing: an experimental study in dogs.

Dynamization of statically locked tibial nails was studied in a canine model. Reamed static interlocking nails were inserted in 16 canine tibiae with unstable osteotomies. At 8 weeks, half were dynamized. At 20 weeks, the tibiae were harvested and studied radiographically, biomechanically, and histologically. Apparent clinical union was present in all tibiae. Complete radiographic bony union was achieved in 13 of 16, with residual radiolucent lines in two tibiae in the static and one in the dynamic group. Biomechanically, dynamization improved stiffness at the fracture site. Histological patterns were similar, but there were trends toward a denser trabecular callus pattern in the dynamized group. The results of this animal study indicate that although dynamization may have a beneficial effect on the quality of early bony healing, static interlocking does not decrease the rate of bony union.

Animals↗
PubMed2000

Post-synchronization of dynamic images of periodically moving organs.

The motion of periodically moving organs can be studied by acquisition of dynamic image series. When time is short, it is necessary either to find a sync signal to sum synchronous images in real time or to acquire a regular time series and to synchronize a posteriori. Dynamic acquisitions were performed (gastric and lung studies). The activity in each pixel of the moving organ can be expressed as h(t)=a0 + a1 cos(omegao0t - phi). The time-activity curve u(t) over a region of interest (ROI) of the considered organ was computed. When the ROI is well chosen, the power spectrum of u(t) exhibits a sharp peak near the characteristic frequency of the periodic motion. The DC component, amplitude and phase in each pixel can be then estimated by minimizing the following function: J=sigma[h(t) - g(t)]2, where g(t) is a noisy measurement of h(t). It is then easy to reconstruct an a posteriori gated time series by computing h(t) for various times over a single period. This approach was successful in characterizing lung and gastric motions. Dynamic series were acquired as for gastric emptying studies. The characteristic frequency of antral motility was easily and unambiguously estimated and DC, amplitude and phase images were computed. Dynamic pulmonary functional imaging was performed with 81Krm. The characteristic frequency was also easily estimated from the time-activity curve power spectrum using a ROI drawn over the lower part of the lungs. The DC, amplitude and phase images were then computed from the dynamic series and the characteristic frequency. In conclusion, a posteriori gating of dynamic series of periodically moving organs can be achieved in a simple fashion. This approach overcomes the difficulty of direct analysis of time-activity curves and provides amplitude and phase images.

Algorithms↗
PubMed1995

Isometric and dynamic performances of the trunk and associated factors.

STUDY DESIGN: Static and dynamic performances of the trunk were measured on an isoinertial device and data were collected regarding the working conditions and the anthropometric and psychosocial characteristics of the workers. OBJECTIVES: To describe the difference in static and dynamic performances of the trunk between workers with and without low back pain and to investigate the anthropometric, personal, and occupational factors associated with these performances. SUMMARY OF BACKGROUND DATA: The isometric torque and the parameters of displacement, velocity, and torque during dynamic tests were chosen to describe the isoinertial performances of the trunk. Dynamic characteristics in particular were investigated because it has been suggested in the literature that these discriminate best between workers with and without low back pain. METHODS: The protocol included a 52-item questionnaire, a clinical examination with a series of anthropometric measurements, and the isometric and dynamic tests (against 25% and 50% of the isometric values) on the isostation. RESULTS: The variables significantly associated with the trunk performances were weight, height, muscularity, sports, and leisure activities as positive factors, and linearity, health problems, and vehicle driving as negative factors. When these covariates were taken into consideration, the significant differences between subjects with and without low back pain were related only to the velocities during dynamic tests, which were reduced by 5.9%. CONCLUSIONS: The performances of the trunk are associated mainly with the anthropometric characteristics of the subjects but also with factors such as lumbar status, health, working conditions, and leisure activities.

Adult↗
PubMed2001

Influence of different types of progressive idiopathic scoliosis on static and dynamic postural control.

STUDY DESIGN: Balance control assessment of static and dynamic conditions was performed to study the effects of progressive idiopathic scoliosis on postural control in 102 adolescents. OBJECTIVE: To determine how the type and location of idiopathic scoliosis may affect global balance control. SUMMARY OF BACKGROUND DATA: Idiopathic scoliosis may impair postural control components, but the repercussions for global balance are relatively mild. METHODS: The following four different types of idiopathic scoliosis were compared: thoracic (n = 36), thoracolumbar (n = 22), lumbar (n = 23), and double major (n = 21) curves. Center of foot pressure displacements and electromyographic responses were recorded using static and dynamic posturographic tests (single and fast upward tilt, slow sinusoidal oscillations). RESULTS: The major criteria of postural control were better in the double major group for all the tests. In the static test, the patients with high major curves performed better than those with low major curves. In the fast dynamic test, similar latency values were observed in all the groups. In the slow dynamic test, better results were observed for the patients with low major curves. CONCLUSIONS: These data demonstrate that idiopathic scoliosis indeed alters balance control, with different hierarchies, from the best to the worst as follows: double major, thoracic, thoracolumbar, and lumbar curves in the static test and double major, lumbar, thoracolumbar, and thoracic curves in the slow dynamic test. The location of the major curve appeared to be important, with an effect on lateral disequilibrium and vestibular symmetry. The absence of anomaly in the fast dynamic test suggests that the type of scoliosis does not impair proprioception.

Adolescent↗
PubMed2001

Dynamic cervical plates: biomechanical evaluation of load sharing and stiffness.

STUDY DESIGN: An in vitro biomechanical study using a simulated cervical corpectomy model to compare the load-sharing properties and stiffnesses of two static and two dynamic cervical plates. OBJECTIVES: To evaluate the load-sharing properties of the instrumentation with a full-length graft and with 10% graft subsidence and to measure the stiffness of the instrumentation systems about the axes of flexion-extension, lateral bending, and axial torsion under these same conditions. SUMMARY OF BACKGROUND DATA: No published reports comparing conventional and dynamic cervical plates exist. METHODS: Six specimens of each of the four plate types were mounted on ultra-high molecular weight polyethylene-simulated vertebral bodies. A custom four-axis spine simulator applied pure flexion-extension, lateral bending, and axial torsion moments under a constant 50 N axial compressive load. Load sharing was calculated through a range of applied axial loads up to 120 N. The stiffness of each construct was calculated in response to +/-2.5 Nm moments about each axis of rotation with a full-length graft, a 10% shortened graft, and no graft. ANOVA and Fisher's post hoc test were used to determine statistical significance (alpha < or = 0.05). RESULTS: The two locked cervical plates (CSLP and Orion) and the ABC dynamic plate were similar in flexion-extension, lateral bending, and torsional stiffness. The DOC dynamic plate was consistently less stiff. The Orion plate load shared significantly less than the other three plates with a full graft. Both the ABC and the DOC plates were able to load share with a shortened graft, whereas the conventional plates were not. CONCLUSIONS: All plates tested effectively load share with a full-length graft, whereas the two dynamic cervical plates tested load share more effectively than the locked plates with simulated graft subsidence. The effect of dynamization on stiffness is dependent on plate design.

Bone Plates↗
PubMed2004

Prediction of fall risk reduction as measured by dynamic gait index in individuals with unilateral vestibular hypofunction.

OBJECTIVE: To determine the effect of vestibular rehabilitation on reduction of fall risk in individuals with unilateral vestibular hypofunction and to identify those factors that predict fall risk reduction. STUDY DESIGN: Retrospective chart review. SETTING: Tertiary referral center. PATIENTS: Forty-seven patients with unilateral vestibular hypofunction, aged 28 to 86 years, who were at risk for falls on initial assessment. INTERVENTION: All patients underwent vestibular rehabilitation including adaptation exercises, designed to improve gaze stability, and gait and balance exercises. MAIN OUTCOME MEASURES: Fall risk (Dynamic Gait Index), visual acuity during head movements (Dynamic Visual Acuity), and subjective complaints were measured initially, at 2-week intervals, and at completion of physical therapy. RESULTS: As a group, the patients had significantly reduced risk for falls (p <0.001) after rehabilitation. Time from onset of symptoms did not affect the efficacy of vestibular rehabilitation. Both older (> or = 65 yr) and younger (< 65 yr) adults showed significant reductions in fall risk with vestibular rehabilitation (p <0.001). However, a significantly greater proportion (Chi2= 0.016) of older adults remained at risk for falls at discharge compared with young adults (45% versus 11%). Initial Dynamic Gait Index and Dynamic Visual Acuity scores predicted fall risk reduction in patients with unilateral vestibular hypofunction. A model was developed using initial Dynamic Gait Index and Dynamic Visual Acuity scores to predict fall risk reduction. CONCLUSIONS: Vestibular rehabilitation is effective in significantly reducing fall risk in individuals with unilateral vestibular deficit. The model predicts fall risk reduction with good sensitivity (77%) and specificity (90%).

Accidental Falls↗
PubMed2003

Effects of immobilization and dynamic compression on intervertebral disc cell gene expression in vivo.

STUDY DESIGN: An in vivo analysis of the intervertebral disc's cellular response to dynamic compression and immobilization was performed using a rat-tail model. OBJECTIVE: To assess the effects of immobilization and short-term dynamic compression on intervertebral disc cell expression of anabolic and catabolic genes. SUMMARY OF BACKGROUND DATA: Static compressive loads applied in vivo alter the composition of the disc matrix and cell viability in a dose-dependent manner. The effects of in vivo dynamic compression, which is a more physiologic load, and reported risk factor for low back pain have not been investigated. METHODS: An Ilizarov-type device was implanted on the rat tail and used to determine the effects from 72 hours of immobilization (n = 6), 2 hours of dynamic compression (1 MPa/0.2 Hz) (n = 8), and the coupled effect of immobilization followed by compression (n = 8). Real-time reverse transcription-polymerase chain reaction was used to measure changes in anabolic and catabolic gene levels relative to both internal control subjects and a sham-operated group (n = 7). RESULTS: Immobilization and dynamic compression affect anabolic and catabolic genes, with an overall downregulation of types 1 and 2 collagen and upregulation of aggrecanase, collagenase, and stromelysin in the anulus. The effects of immobilization and compression appear to be additive for collagen types 1 and 2 in the anulus, but not in the nucleus, and not for catabolic genes. CONCLUSIONS: Short-duration dynamic compression and immobilization alter gene expression in the rat disc. In studying the response of the disc to loading, it is necessary to look at both anabolic and catabolic pathways, and to consider strain history.

Aggrecans↗
PubMed2003

Dynamic contrast-enhanced magnetic resonance imaging of osteoporotic vertebral fracture.

STUDY DESIGN: This was a retrospective study of the relation between the blood perfusion of bone marrow in injured vertebrae and the degree of subsequent vertebral collapse in patients with osteoporotic vertebral fractures. OBJECTIVE: The objective was to evaluate blood perfusion of bone marrow in injured vertebrae using dynamic magnetic resonance imaging and study the possibility of predicting the progression of vertebral collapse. SUMMARY OF BACKGROUND DATA: Avascular necrosis of the vertebra is considered to be a cause of delayed vertebral collapse following osteoporotic vertebral fractures, but studies on the relation with the degree of progression of vertebral collapse by evaluation of vertebral blood perfusion have not been reported. METHODS: The subjects were 15 vertebrae in 14 patients with osteoporotic vertebral fractures, including 11 women and three men with a median age of 79 years. All patients underwent dynamic magnetic resonance imaging soon after the fracture and the area rate of the noncontrast region of the injured vertebrae in dynamic magnetic resonance imaging was measured. The correlation with the degree of progression of vertebral collapse obtained from plain radiograph imaging was studied. RESULTS: The vertebral collapse rate (percentage loss in vertebral body height) on initial examination was 17 +/- 10% (mean +/- SD) and that at the final examination was 33 +/- 19%, showing a progression of 16 +/- 11%. The noncontrast area rate in dynamic magnetic resonance imaging was 18 +/- 12%. A significant correlation was found between the degree of progression of vertebral collapse and the noncontrast area rate (Spearman r = 0.97, P < 0.001). CONCLUSIONS: The subsequent progression of vertebral collapse tended to increase the greater the noncontrast area in the injured vertebrae in dynamic magnetic resonance imaging. Dynamic magnetic resonance imaging appears to be useful in predicting the progression of collapse of fractured vertebrae.

Aged↗