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PubMed1997

X-ray of trunk rotation.

OBJECTIVE: To establish the mechanism of the thoracolumbar spine during trunk rotation and its restriction. DESIGN: Patients with one-sided rotation restriction were examined seated on a chair with the pelvis fixed in neutral position, at maximum right and left trunk rotations, before and after mobilization of movement restriction; anteroposterior X-rays were taken with a horizontal beam on a vertical X-ray cassette. SETTING: University neurology clinic. MAIN OUTCOME CRITERIA: Assessment of rotation and side bending of the thoracolumbar spine (a) on the normal and the restricted side and (b) after mobilization. RESULTS: In all cases, there was both (coupled) rotation and side flexion during side bending, except that the thoracolumbar junction was frequently near midline; in such cases, the thoracic spine above was bent in the opposite direction. Both rotation and side-bending started at L5 and continued gradually in a cranial direction without a noticeable maximum at any level. CONCLUSIONS: Although it is generally assumed that the configuration of the lumbar zygapophyseal joints precludes axial rotation in the lumbar spine, I find that, during trunk rotation, a coupled movement of side bending and rotation takes place in the lumbar spine and continues without a noticeable break into the thoracic spine. The site of movement restriction, which usually seems to be located at the thoracolumbar junction, cannot be visualized on X-rays.

Adult↗
PubMed1998

[Reduction of apomorphine-induced rotation in rats with additional destruction of the pedunculopontine nucleus contralateral to the unilateral nigrostriatal lesion].

Pedunculopontine nucleus (PPN) has been proposed to be one of the responsible sites for dopamine agonist induced contraversive rotation in rats with unilateral dopaminergic denervation. However, previous experiments have not confirmed possible participation of PPN in this rotational behavior. To determine whether contralateral side of the PPN plays a vital role in this rotation, we investigated apomorphine induced rotation in rats with further destruction of unilateral PPN contralateral to the nigrostriatal lesion. First, rats with unilateral PPN lesioned with N-methyl-D aspartic acid (NMDA) showed contralateral rotation when they were injected with apomorphine 0.5 mg/kg s.c. Second, rats with right substantia nigra previously lesioned with 6-hydroxydopamine were microinjected with NMDA (PPN lesion group) or vehicle (sham lesion group) into the contralateral (left)side of the PPN. Contraversive rotation induced by apomorphine 0.05 mg/kg s.c. did not show any significant change in PPN lesion group as compared with sham lesion group. Whereas such rotation induced by apomorphine 0.5 mg/kg s.c. significantly reduced to 61% in PPN lesion group as compared with that in sham lesion group. These results could be interpreted as a partial cancellation of rotational activity to the contralateral side (left) by the potential rotational activity toward the opposite side (right) in rats with additional contralateral PPN lesion. Although PPN might not serve as an output route for the dopaminergic neurotransmission in the basal ganglia, PPN itself could rather induce some movement affecting the basal ganglia.

Animals↗
PubMed1992

Fluoroscopic comparison of kinematic patterns in massive rotator cuff tears. A suspension bridge model.

Twelve shoulders with known massive rotator cuff tears were imaged fluoroscopically. The observed kinematic patterns were correlated with the known locations of the rotator cuff tears. Three kinematic patterns emerged: Type I, stable fulcrum kinematics associated with tears of the superior rotator cuff (supraspinatus and a portion of the infraspinatus); Type II, unstable fulcrum kinematics associated with tears that involved virtually all of the superior and posterior rotator cuff; and Type III, captured fulcrum kinematics associated with massive tears that involved the supraspinatus, a major portion of the posterior rotator cuff, and a major portion of the subscapularis. In Type III, an "awning effect" of the acromion was observed to influence active motion. Based on the recorded kinematic patterns, a biomechanical model was developed comparing the rotator cuff tear to a suspension bridge (loaded cable). A biomechanical analysis of forces acting on the rotator cuff according to this model yielded data that supported the contention that certain rotator cuff tears in older individuals may be adequately treated with debridement and decompression, without repair.

Fluoroscopy↗
PubMed2005

Effect of job rotation on need for recovery, musculoskeletal complaints, and sick leave due to musculoskeletal complaints: a prospective study among refuse collectors.

BACKGROUND: Job rotation might be an effective preventive measure to reduce the prevalence of musculoskeletal complaints, although its effect has not been yet established. The aim of the present study is to evaluate the effect of job rotation in refuse collecting on need for recovery, prevalence of musculoskeletal complaints, and sick leave due to musculoskeletal complaints. METHODS: A 1-year prospective study among refuse collectors was performed, using standardized questionnaires. Job rotation was performed between collecting two-wheeled containers and driving a refuse truck. The experimental groups of rotating refuse collectors at t(0) and t(1) (group R-R) and non-rotating refuse collectors at t(0) and rotating refuse collectors at t(1) (group NR-R) were compared with a reference group of non-rotating refuse collectors at t(0) and t(1) (group NR-NR). RESULTS: The adjusted need for recovery of group R-R was marginally significantly lower than need for recovery of the reference group. Groups R-R and NR-R had a more than two times higher risk for complaints of the low back than the reference group. No other significant results were found. CONCLUSIONS: Job rotation seemed to coincide with a reduced need for recovery and was associated with an increased risk of low back complaints. No effects were found on sick leave due to musculoskeletal complaints. The results might be influenced by the healthy worker selection effect in the reference group and its inverse in the rotating groups.

Adult↗
PubMed2004

Randomized study of the safety and clinical utility of rotational angiography versus standard angiography in the diagnosis of coronary artery disease.

This study evaluates the safety and clinical utility of rotational angiography in the diagnosis of coronary artery disease. High-speed rotational angiography is a newly available angiographic modality that gives a dynamic multiple-angle perspective of the coronary tree during a single contrast injection. We prospectively randomized 56 patients referred for diagnostic coronary angiography to either standard or rotational angiography. Contrast and radiation utilization were compared between the two groups. The number of additional cine acquisitions needed was used to determine adequacy of the diagnostic study protocol. Rotational angiography was successfully completed in all subjects. There was a 33% reduction in contrast utilization in the rotational group as compared to the standard group (35.6 +/- 12.6 vs. 52.8 +/- 10.7 ml, respectively; P < 0.0001). Additionally, there was a 28% reduction in total radiation exposure in the rotational group as compared to the standard group (39.0 +/- 18.5 vs. 53.9 +/- 23.4 Gycm(2), respectively; P = 0.01). Total whole-body radiation exposure to the primary operator was 144 mrem with rotational angiography and 170 mrem with standard angiography. Procedure time tended to be shorter for rotational angiography (353.9 +/- 146.7 vs. 396.8 +/- 165.8 s; P = 0.3). Rotational coronary angiography can be rapidly performed in any patient and provides a significant reduction in contrast and radiation utilization while at the same time providing adequate angiographic data to complement or replace standard coronary angiography in the evaluation of coronary artery disease.

Adult↗
PubMed1986

Optic fibers follow aberrant pathways from rotated eyes in Xenopus laevis.

The rotated eye paradigm has been a major experimental test of the neuronal specificity model for the development of ordered retinotectal connections in amphibians. In most studies, however, no optic fiber pathways were traced from rotated eyes and correlated with visuotectal projections. As an initial approach to this question, optic fibers from eyes rotated at different embryonic stages were traced with 3H-proline autoradiography. Three experimental series were prepared: in situ eye rotations, isochronic transplants of eyes rotated between embryos at the same stage, and heterochronic transplants of eyes rotated between embryos at different stages. Single or multiple optic fiber pathways developing from rotated eyes are identified by their sites of entry and trajectory in the brain. These include a normal chiasmatic (CH) pathway, and three aberrant pathways, identified as trigeminal (TR), diencephalic (DI), and oculomotor (OC). The latter three enter the brain ipsilaterally, some crossing contralaterally via commissural pathways. Depending on stage and type of operation, TR pathways develop in 50-100% of the animals, while CH pathways are more common after rotation at stage 21/22. The surgical procedure affects the initial trajectory of fibers from the retina, perturbs guidance cues in the surrounding orbit, and determines the patterns of optic pathways that develop. In most cases, optic fibers follow motor (oculomotor) or sensory (trigeminal) nerves, usually the first fibers encountered near the orbit by axonal pioneers exiting the retina. Evidently, optic fibers exhibit no pathway selectivity; any axon serves as a guidance cue. Tecta are innervated in about 50% of the cases, usually by fibers following abnormal trajectories from CH and OC pathways. The results suggest that the development of ordered visuotectal projections from rotated eyes is a complex process that may be independent of the trajectory of fiber arrival. Unless pathways and visuotectal maps are directly compared in each animal, however, the question remains open because we still do not know which anomalous pathways, if any, correlate with ordered projections.

Animals↗
PubMed1988

Frequency and velocity of rotational head perturbations during locomotion.

We used the magnetic search coil technique to record horizontal (yaw) and vertical (pitch) head rotations of 20 normal subjects during (1) walking in place, (2) running in place, (3) vigorous, voluntary, horizontal head rotation and (4) vigorous, voluntary, vertical head rotation. During walking or running, the predominant frequency of pitch rotations was at least twice that of yaw rotations. During running, the median, predominant pitch frequency from all subjects was 3.2 Hz, but significant harmonics were present up to 15-20 Hz in several subjects. Group median maximal head velocity during walking or running did not exceed 90 degrees/second. During vigorous, voluntary head rotations median frequency for yaw and pitch was similar and did not exceed 2.6 Hz. However, group median maximal head velocity during vigorous voluntary yaw rotation was 780 degrees/second. Thus, (1) during locomotion, the head is stabilized in space incompletely but adequately so that the vestibulo-ocular reflex (VOR) is not saturated, (2) during vigorous, voluntary head rotations, the maximum head velocity exceeds the range where the VOR can stabilize gaze, (3) the frequencies of head rotations that occur during locomotion greatly exceed frequencies conventionally used in the laboratory for testing the VOR.

Adult↗
PubMed1976

Drug-induced rotation in rats without lesions: behavioral and neurochemical indices of a normal asymmetry in nigro-striatal function.

Normal unoperated rats were tested for rotation (i.e., circling behavior) in a spherical "rotometer" and dose-response relationships were generated using d-amphetamine, apomorphine, L-Dopa, haloperidol, and scopolamine. The rotation induced by amphetamine was significantly antagonized by alpha-methyl-p-tyrosine and haloperidol, but not by diethyldithiocarbamate. The rotation elicited by apomorphine was unaffected by alpha-methyl-p-tyrosine. Rotation was not necessarily in the same direction with high and low doses of amphetamine, or amphetamine and apomorphine administered a week apart from each other. Dopaminergic-cholinergic interactions were evident, since pilocarpine antagonized amphetamine-induced rotation whereas scopolamine did not; scopolamine elicited rotation in the same direction as that induced by amphetamine. Left and right striatal dopamine and tel-diencephalic norepinephrine levels were determined in rats injected with various doses of amphetamine and tested for rotation. There were significant bilateral differences in striatal dopamine which were related to the direction of rotation. Since amphetamine was found to be equally distributed to the two sides of the brain, the difference in striatal dopamine appeared to be the neurochemical substrate for rotation in normal rats. These results suggest that normal rats have asymmetrical levels of striatal dopamine as well as an asymmetrical complement of striatal dopamine receptors.

Animals↗
PubMed1995

The muscarine antagonist methscopolamine and the NMDA antagonist AP-5 injected unilaterally into the nucleus accumbens cause mice to rotate in opposite directions.

Previously, we have reported that the NMDA antagonist AP-5, injected unilaterally into the nucleus accumbens of mice, induces ipsilateral rotation in monoaminergically intact mice, but contralateral rotation in monoamine-depleted animals. In this paper we report that the muscarine antagonist methscopolamine, injected unilaterally into the nucleus accumbens, induced predominantly contralateral rotation in monoaminergically intact mice. In monoamine-depleted animals intra-accumbens methscopolamine induced only a weak stimulation of rotational behaviour (not significant), but the direction of the rotation was exclusively contralateral, and the animals showed contralateral body deviation. Moreover, when these animals received additional treatment with the alpha-adrenergic agonist clonidine, which potentiates the motor effects of cholinergic antagonists in monoamine-depleted mice (Carlsson et al., 1991), a clear-cut contralateral rotation was induced. The observed behavioural effects are discussed in relation to the positive and negative feedback circuits, which link the nucleus accumbens with the cerebral cortex and thalamus. In previous papers, we have suggested that the ipsilateral rotation induced by AP-5 is mediated primarily by the positive feedback circuit, whereas the AP-5-induced contralateral rotation is due to interference with primarily the negative feedback circuit. Applying this reasoning to the rotational effects of methscopolamine, it seems that methscopolamine interferes primarily with the negative feedback circuit.

2-Amino-5-phosphonovalerate↗
PubMed2000

The coracoacromial ligament: anatomical and biomechanical properties with respect to age and rotator cuff disease.

The coracoacromial ligament (CAL) plays an important role in the pathoetiology of the subacromial impingement syndrome especially in those patients who do not have bony abnormalities. A total of 40 shoulders were dissected to determine the anatomical and biomechanical properties of the CAL in shoulders with either intact rotator cuffs or rotator cuff disease, taken from cadavers of persons who were of various ages at death. The specimens from cadavers with rotator cuff degeneration had a shorter lateral and medial band of the CAL than those of the specimens taken from shoulders with intact rotator cuffs. The cross-sectional area of the lateral band was also enlarged in older specimens with rotator cuff degeneration. Analysis of the structural properties showed a higher load to failure and a higher stiffness in the younger than in older specimens. In material properties, there was a higher failure stress in specimens with normal rotator cuffs than in the specimens with rotator cuff disease but only in older specimens. The decreased material properties in older specimens with rotator cuff disease may be caused by the previously reported histological differences with tissue disorganization and a lack of parallel bundle orientation associated with rotator cuff disease.

Adult↗
PubMed2003

Vergence-mediated changes in the axis of eye rotation during the human vestibulo-ocular reflex can occur independent of eye position.

The aim of this study was to determine whether vergence-mediated changes in the axis of eye rotation in the human vestibulo-ocular reflex (VOR) would obey Listing's Law (normally associated with saccadic eye movements) independent of the initial eye position. We devised a paradigm for disassociating the saccadic velocity axis from eye position by presenting near and far targets that were centered with respect to one eye. We measured binocular 3-dimensional eye movements using search coils in ten normal subjects and 3-dimensional linear head acceleration using Optotrak in seven normal subjects. The stimuli consisted of passive, unpredictable, pitch head rotations with peak acceleration of approximately 2000 degrees /s(2 )and amplitude of approximately 20 degrees. During the pitch head rotation, each subject fixated straight ahead with one eye, whereas the other eye was adducted 4 degrees during far viewing (94 cm) and 25 degrees during near viewing (15 cm). Our data showed expected compensatory pitch rotations in both eyes, and a vergence-mediated horizontal rotation only in the adducting eye. In addition, during near viewing we observed torsional eye rotations not only in the adducting eye but also in the eye looking straight ahead. In the straight-ahead eye, the change in torsional eye velocity between near and far viewing, which began approximately 40 ms after the start of head rotation, was 10+/-6 degrees /s (mean +/- SD). This change in torsional eye velocity resulted in a 2.4+/-1.5 degrees axis tilt toward Listing's plane in that eye. In the adducting eye, the change in torsional eye velocity between near and far viewing was 16+/-6 degrees /s (mean +/- SD) and resulted in a 4.1+/-1.4 degrees axis tilt. The torsional eye velocities were conjugate and both eyes partially obeyed Listing's Law. The axis of eye rotation tilted in the direction of the line of sight by approximately one-third of the angle between the line of sight and a line orthogonal to Listing's plane. This tilt was higher than predicted by the one-quarter rule. The translational acceleration component of the pitch head rotation measured 0.5 g and may have contributed to the increased torsional component observed during near viewing. Our data show that vergence-mediated eye movements obey a VOR/Listing's Law compromise strategy independent of the initial eye position.

Adult↗
PubMed2006

Rasterstereographic analysis of axial back surface rotation in standing versus forward bending posture in idiopathic scoliosis.

The forward bending test according to Adams and rib hump quantification by scoliometer are common clinical examination techniques in idiopathic scoliosis, although precise data about the change of axial surface rotation in forward bending posture are not available. In a pilot study the influence of leg length inequalities on the back shape of five normal subjects was clarified. Then 91 patients with idiopathic scoliosis with Cobb-angles between 20 degrees and 82 degrees were examined by rasterstereography, a 3D back surface analysis system. The axial back surface rotation in standing posture was compared with that in forward bending posture and additionally with a scoliometer measurement in forward bending posture. The changes of back shape in forward bending posture were correlated with the Cobb-angle, the level of the apex of the scoliotic primary curve and the age of the patient. Averaged over all patients, the back surface rotation amplitude increased from 23.1 degrees in standing to 26.3 degrees in forward bending posture. The standard deviation of this difference was high (6.1 degrees ). The correlation of back surface rotation amplitude in standing with that in forward bending posture was poor (R (2)=0.41) as was the correlation of back surface rotation in standing posture with the scoliometer in forward bending posture measured rotation (R (2)=0.35). No significant correlation could be found between the change of back shape in forward bending and the degree of deformity (R (2)=0.07), likewise no correlation with the height of the apex of the scoliosis (R (2)=0.005) and the age of the patient (R (2)=0.001). Before forward bending test leg length inequalities have to be compensated accurately. Compared to the standing posture, forward bending changes back surface rotation. However, this change varies greatly between patients, and is independent of the type and degree of scoliosis. Furthermore remarkable differences were found between scoliometer measurement of the rib hump and rasterstereographic measurement of the vertebral rotation. Therefore the forward bending test and the identification of idiopathic scoliosis rotation by scoliometer can be markedly different compared to rasterstereographic surface measurement in the standing posture.

Back↗
PubMedDate not supplied

Neck extension and rotation in sudden infant death syndrome and other natural infant deaths.

It has been hypothesized that some cases of sudden infant death syndrome (SIDS) are a result of neck extension and/or rotation that causes vertebral artery (VA) compression and brain stem ischemia. There is a paucity of relevant literature on this topic. Therefore, our aim was to compare neck rotation and extension in SIDS and other natural infant deaths. Cases of SIDS and other natural infant deaths within the San Diego SIDS Research Project database were analyzed retrospectively with respect to neck and body position as reported by the trained, experienced scene investigators and/or the caretakers who discovered the infants. Information was used from 246 SIDS cases and 56 cases of other natural deaths. Simultaneous neck extension and rotation was not reported in either group. When data regarding neutral/flexed/extended position and rotation of the neck were combined, no significant differences were found between the two groups (P = 0.94); 40% of the SIDS cases and 41% of the other natural death cases were found with the neck either extended or rotated (odds ratio [OR] 0.97, [reference group = neck either neutral or flexed, and not rotated], 95% confidence interval [CI] 0.45, 2.11). There were also no significant differences between the groups when neck rotation and neck extension were analyzed independent of one another. Neck rotation among cases found in the prone position was common and was not significantly different between the two groups (49% of 146 SIDS cases, 58% of 24 other natural death cases, P = 0.38, OR 0.68, 95% CI 0.28, 1.62). Neck rotation among infants found in the supine position occurred one-third as often in the SIDS group (9% of 33 cases) as in the other natural death group (29% of 14 cases); however, the difference was not significant (P = 0.17; OR 0.25, 95% CI 0.05, 1.31). Although our analysis does not exclude VA compression and brain stem ischemia in some cases of SIDS, we found no evidence to affirm its importance. This study demonstrates the importance of meticulous scene descriptions, including neck position.

Female↗
PubMed2006

A simple derivation of the luminescence anisotropy decay from randomly distributed cylinders rotating about a single axis.

A simple derivation is given of the expression describing the anisotropy decay of luminescence for a solution of molecules that can only undergo rotational diffusion about a single cylindrical axis. The usual derivations of the anisotropy decay for this cylindrical model have simply taken limiting cases of the equations resulting from the general treatment of the anisotropy decay of a completely anisotropic rotator or the rotation of an ellipsoid. The arguments presented here can be understood without the mathematical sophistication required to follow the general derivations for the rotational diffusion of a completely anisotropic rotator or ellipsoids. The underlying physical mechanisms leading to a multiple exponential decay of the fluorescence anisotropy signal from a single axis rotating cylinder are clearly shown by following this derivation. The resulting expression for the anisotropy decay is not new. However, the derivation is easily understood, and this article is meant as an introduction to the more advanced treatments of anisotropy decay by rotational diffusion. After presenting the derivation of the rotating cylinder, the corresponding steps of these general treatments and this simple model are indicated. The model is of special interest for describing the anisotropy decay resulting from rotations of proteins within membranes.

Journal Article↗
PubMed1995

Effect on blood flow of rotation and position of the internal mammary artery pedicle.

The internal mammary artery is the preferred conduit for coronary artery bypass grafts. The effect on flow through the artery of both rotation and position of the artery pedicle was tested in an in-vitro setting on 20 arteries using a perfusate closely approximately the normothermic viscosity of blood. It was found that the effect of rotation on blood flow was highly significant (p < 0.0004) and that this occurs after a degree of rotation that is dependent on the pedicle length. The critical degree of rotation required to significantly affect blood flow is 30 degrees for each centimeter of pedicle length. The degree of rotation required to stop flow altogether is 45 degrees per unit length. Flow through the arteries was found to be inversely proportional to the length of the artery but was not affected by changes in the position of the artery provided there was not a rotational component. Tension of the pedicle did not influence flow in either a linear or rotated position. These results were verified in a clinical setting. This study supports that a 180-degree rotation of the internal mammary artery pedicle in any clinical setting will not alter blood flow. For rotations of 360 degrees or greater, however, the effect on flow becomes significant when this is 12 cm or less. Although flow is independent of linear pedicle deformity, as flow is inversely proportional to length, excess pedicle length is best avoided.

Blood Flow Velocity↗
PubMed1990

Rotation in response to selective dopamine receptor agonists in rats with electrolytic substantia nigra lesions.

Rats with unilateral, electrolytic substantia nigra (ESN) lesions were tested for rotation following systemic injections of the D1 dopamine receptor agonist SKF38393 or the D2 agonist quinpirole. Only quinpirole produced significant levels of rotation, which was ipsilateral in direction. This rotation was potentiated by coadministration of the D1 agonist, and was significantly reduced by injections of either a D1 or D2 receptor antagonist. Other groups of lesioned animals were treated with reserpine for 5 days and were then tested for rotation in response to the agonists. In this case, SKF38393 produced significant levels of contralateral rotation, while quinpirole-induced rotation remained ipsilateral; coadministration of the D1 and D2 agonists resulted in pronounced ipsilateral rotation. These results stress a role for D1 receptor mechanisms in producing rotation, and suggest that different striatal efferent pathways mediate rotation in response to selective agonists following ESN lesions.

2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-ben↗
PubMed1986

Differences in spontaneous and amphetamine-induced rotational behavior, and in sensitization to amphetamine, among Sprague-Dawley derived rats from different sources.

Nocturnal rotational behavior was found to vary severalfold among Sprague-Dawley derived rats obtained from seven different breeders; net rotations per night (18 hours) varied from 5.0 to 31.0 in males and from 6.2 to 42.4 in females. Rats from three sources were tested twice (a week between tests) for rotation induced by d-amphetamine. Rats from two sources showed evidence of sensitization to d-amphetamine, there being significantly greater rotation in response to the second dose than in response to the first dose; the d-amphetamine-induced rotational behavior of rats from the third source did not significantly change from one week to the next. However, the latter rats had a greater initial response to the first dose of d-amphetamine than did rats from the other two breeders. Further analysis revealed that, among rats from all three breeders, rats rotating weakly in response to d-amphetamine on the first test tended to rotate more on the second test whereas rats rotating strongly in response to d-amphetamine on the first test tended to rotate less on the second test. This relationship was found to apply to previously collected data as well and was discussed with reference to a proposed mechanism involving asymmetry in sensitization to d-amphetamine-induced release of striatal dopamine. Interindividual differences among seemingly similar experimental subjects appear to contribute importantly to reported differences in results among laboratories.

Animals↗
PubMed2007

Assessment of left ventricular rotation and torsion with two-dimensional speckle tracking echocardiography.

BACKGROUND: Speckle tracking echocardiography (STE) has a unique feature of angle independence and, thus, may provide a powerful means of assessing left ventricular (LV) torsion (LVtor). The aims of this study were to assess: (1) the feasibility of 2-dimensional STE in the measurement of LVtor; and (2) the relationship of LVtor with age and conventional echocardiographic parameters. METHODS: We consecutively recruited 160 healthy volunteers. After obtaining conventional echocardiographic parameters, apical and basal short-axis rotations were assessed with STE. LVtor was defined as the net difference between rotation angles in the two short-axis planes normalized for LV longitudinal length. RESULTS: Reliable LVtor measurement was possible only in 56 volunteers (35%). This low feasibility was largely a result of the failure to obtain reliable basal rotation values. In 56 volunteers who were finally enrolled in this study, a significant correlation was found between LV ejection fraction and LVtor (r = 0.56, P < .001) and this correlation was attributed to apical (r = 0.47, P < .001) but not basal (P = .14) rotation. There was no significant change in LVtor with aging. However, initial counterclockwise motion (r = -0.51, P = .001) and its interval (r = -0.44, P = .001) in the basal rotation gradually decreased with aging, and correlated with early transmitral inflow velocity (r = 0.44 and 0.49, respectively) and its deceleration time (r = -0.43 and -0.48, respectively) (all P < .001). In contrast, such correlations were not found for initial clockwise motion and its interval in the apical rotation. CONCLUSIONS: Currently, STE has limited feasibility in the measurement of LVtor. There was no significant age-related change in LVtor. In LV rotations, basal rotation was affected by the age-related changes in the LV early diastolic filling, whereas apical rotation was mainly related to LV systolic performance.

Adult↗