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PubMed1993

Regional wall motion analysis predicts survival and functional outcome after subendocardial resection in patients with prior anterior myocardial infarction.

BACKGROUND: Subendocardial resection is an established surgical technique for the treatment of ventricular tachycardia associated with prior myocardial infarction. Preoperative factors predictive of survival and functional outcome after surgery have not been completely characterized. We hypothesized that a quantitative assessment of regional wall motion would be a sensitive predictor of both survival and functional outcome after subendocardial resection. This was retrospectively tested in a group of 80 patients with prior anterior myocardial infarction who had undergone subendocardial resection for sustained ventricular tachycardia at out institution. METHODS AND RESULTS: Centerline chord motion analysis was used to derive a wall motion score from the preoperative contrast right anterior oblique ventriculogram. Multivariate analysis revealed wall motion score to be a significant independent predictor of both long-term survival (p < 0.01) and New York Heart Association (NYHA) functional class I or II status at 6 months (p < 0.01) and at 24 months (p < 0.001) after surgery. Patients with a wall motion score of > 16%, compared with patients with a wall motion score of < or = 16%, had a better 5-year actuarial survival (74% versus 45%, p = 0.02) and were more likely to be NYHA class I or II at 6 months (87% versus 58%, p < 0.01) and at 24 months (82% versus 34%, p < 0.0001) after subendocardial resection. CONCLUSIONS: A wall motion score derived from centerline chord motion analysis is a sensitive predictor of survival and functional outcome after subendocardial resection. Patients with a wall motion score of > 16% have an excellent prognosis after subendocardial resection. In contrast, patients with a wall motion score of < or = 16% have a poorer outcome and should be considered candidates only if other forms of therapy have failed or are unavailable.

Cardiac Pacing, Artificial↗
PubMed1997

In vivo skeletal responses to porous-surfaced implants subjected to small induced motions.

Cylindrical porous-coated implants were placed in the distal femoral metaphyses of twenty dogs and were subjected to zero, twenty, forty, or 150 micrometers of oscillatory motion for eight hours each day for six weeks with use of a specially designed loading apparatus. The in vivo skeletal responses to the different magnitudes of relative motion were evaluated. Histological analysis demonstrated growth of bone into the porous coatings of all of the implants, including those that had been subjected to 150 micrometers of motion. However, the ingrown bone was in continuity with the surrounding bone only in the groups of implants that had not been subjected to motion or that had been subjected to twenty micrometers of motion; in contrast, the implants that had been subjected to forty micrometers of motion were surrounded in part by trabecular bone but also in part by fibrocartilage and fibrous tissue, and those that had been subjected to 150 micrometers of motion were surrounded by dense fibrous tissue. Trabecular microfractures were identified around three of the five implants that had been subjected to forty micrometers of motion and around four of the five that had been subjected to 150 micrometers of motion, suggesting that the ingrown bone had failed at the interface because of the large movements. The architecture of the surrounding trabecular bone also was altered by the micromotion of the implant. The implants that had stable ingrowth of bone were surrounded by a zone of trabecular atrophy, whereas those that had unstable ingrowth of bone were surrounded by a zone of trabecular hypertrophy. The trabeculae surrounding the fibrocartilage or fibrous tissue that had formed around the implants that had been subjected to forty or 150 micrometers of motion had been organized into a shell of dense bone tangential to the implant (that is, a neocortex outside the non-osseous tissue).

Animals↗
PubMed2004

Normal diaphragmatic motion and the effects of body composition: determination with M-mode sonography.

OBJECTIVE: To evaluate the quantitative measurement of diaphragmatic motion in healthy subjects and to investigate the effects of different variables such as body mass index and waist circumference on the diaphragmatic motion. METHODS: The study included 164 healthy subjects. The subjects were grouped according to age, sex, body mass index, and waist circumference. Measurements of diaphragmatic motion were made by a 3.5-MHz sonographic unit in the M-mode of the system. The posterior diaphragm on both sides was identified, and measurements were performed during deep inspiration. RESULTS: The mean diaphragmatic motion measurements +/- SD were 49.23 +/- 10.98 and 50.17 +/- 11.73 mm on right and left sides, respectively. Female subjects had statistically significantly (P < .05) decreased diaphragmatic motion (right, 46.93 +/- 10.37 mm; left, 47.57 +/- 10.36 mm) than male subjects. The mean diaphragmatic motion (right, 40.90 +/- 8.89 mm; left, 39.37 +/- 9.15 mm) was less in subjects who were underweight (P < .05) when compared with subjects who were of normal weight, overweight, and obese. Subjects who had a waist circumference of less than 70 cm showed a statistically significant decrease (P < .05) in diaphragmatic motion (right, 42.55 +/- 9.12 mm; left, 42.24 +/- 9.73 mm) when compared with subjects who had a waist circumference of 70 to 85, 85 to 100, and greater than 100 cm. Also, subjects younger than 30 years had statistically significantly (P < .05) decreased diaphragmatic motion (right, 44.57 +/- 10.57 mm; left, 44.44 +/- 11.37 mm). CONCLUSIONS: Sex, body mass index, waist circumference, and age may affect the diaphragmatic motion to some extent. Healthy persons of younger age with a smaller body mass index and waist circumference may show a decreased amount of diaphragmatic motion.

Adolescent↗
PubMed1999

MR imaging of cerebrospinal fluid flow and spinal cord motion in neurologic disorders of the spine.

In summary, MR imaging of CSF and cord motion helps to evaluate diseases affecting cord and CSF motion and to identify the specific pathophysiology involved. A number of significant points have been made. First, MR imaging flow studies can be useful in evaluating CSF spaces and cystic diseases. Second, longitudinal and transverse motions occur in the spinal cord and CSF. Traveling wave motion occurs along the length of the spinal cord. Third, spinal cord tethering is associated with decreased cord velocity and loss of cord displacement at tethering site. Decreased transverse velocities occur with lateral cord tethering to the spinal canal. Fourth, in spinal dysraphism, longitudinal cord velocity is decreased by tethering, and is normal in asymptomatic patients with low conus. Normal cord motion helps to rule out possible tethering in symptomatic dysraphism with hydromyelia. Fifth, in acquired and nonmyelodysplastic symptomatic tethering, spinal cord motion is decreased. Sixth, in symptomatic cord compression, CSF flow and cord motion decrease, but recover after surgical decompression and after compensatory atrophy. Seventh, in asymptomatic spinal stenosis, cord motion is normal or increased. Diffuse spinal stenosis with cord atrophy leads to diffuse cord acceleration and prolonged cord caudal velocity, possibly related to the loss of the transverse mobility of the cord. Finally, focal spinal stenosis leads to focal dynamic cord deformation and can be associated with prominent intramedullary deformations. When compression is severe or symptomatic, cord motion is significantly decreased. Postoperative cases demonstrate good recovery of cord and CSF motion, unless compression or obstruction is still present.

Cerebrospinal Fluid↗
PubMed2000

Correlation between interventricular septal motion and left ventricular systolic-diastolic function in patients with left bundle branch block.

The echocardiographic correlation between abnormal interventricular septal motion including systolic paradoxical, flat motion and early diastolic notch and ejection fraction, mean ventricular circumferential fiber shortening and early diastolic mitral filling velocity was studied in 46 patients with complete left bundle branch block. Systolic normal interventricular septal motion was used as the control. Ejection fraction was significantly smaller in the paradoxical(0.44 +/- 0.13, p < 0.02) and flat motion groups(0.38 +/- 0.09, p < 0.001) than in the normal group(0.54 +/- 0.1). Mean ventricular circumferential fiber shortening was significantly smaller in the flat motion group than in the normal group(0.72 +/- 0.19 vs 0.99 +/- 0.23 circ/sec, p < 0.002). The size of the notch was significantly smaller in the flat motion group than in the normal group (2.3 +/- 0.2 vs 4.8 +/- 0.8 mm, p < 0.0001). The deceleration rate of the notch was significantly slower in the paradoxical and flat motion groups than in the normal group(37.3 +/- 12.2, 31.3 +/- 8.1 vs 69.1 +/- 2.5 cm/sec, p < 0.0001). Early diastolic mitral filling velocity was slower in the flat motion group than in the other 2 groups. In conclusion, systolic flat interventricular septal motion showed more severe disturbances of left ventricular systolic and diastolic function than paradoxical interventricular septal motion in patients with complete left bundle branch block.

Aged↗
PubMed2002

Incremental value of assessment of regional wall motion for detection of multivessel coronary artery disease in exercise (201)Tl gated myocardial perfusion imaging.

UNLABELLED: Assessment of reversible perfusion defects in exercise (201)Tl perfusion SPECT has low sensitivity and high specificity for detection of multivessel coronary artery disease (CAD). The goal of this study was to evaluate whether worsening of left ventricular regional wall motion assessed by an automated algorithm in exercise (201)Tl electrocardiography-gated SPECT had incremental diagnostic value over perfusion data for detection of multivessel CAD. METHODS: Two hundred one patients underwent exercise (201)Tl gated SPECT. Software that automatically analyzes left ventricular function was used to assess exercise and rest regional wall motion. Regional wall motion on initial images was compared with that on rest images, that is, delayed images for patients without reinjection images and reinjection images for patients with reinjection images. The left ventricle was divided into 9 segments, with individual segments assigned to 3 coronary territories. Worsening of wall motion was defined as worsening in any segment on initial images compared with rest images. RESULTS: Of 73 patients with multivessel CAD, 20 (27.4%) had reversible perfusion defects in multiple coronary territories, 26 (35.6%) exhibited worsening of regional wall motion in multiple territories, and 37 (50.7%) had reversible perfusion defects or worsening of regional wall motion in multiple territories. The sensitivity of the combination of reversible perfusion defect and worsening of regional wall motion was significantly higher than that of reversible perfusion defect alone for detection of multivessel CAD (50.7% vs. 27.4%, P < 0.05). The specificity of the combination of reversible perfusion defect and worsening of regional wall motion for detecting multivessel CAD did not differ from that of reversible perfusion defect alone and that of worsening of regional wall motion alone (94.5% vs. 99.2% and 97.7%, respectively, P = not statistically significant). CONCLUSION: Combined assessment of worsening of left ventricular regional wall motion by exercise and perfusion data in exercise (201)Tl gated myocardial SPECT was more sensitive, with acceptable specificity, than was assessment with perfusion data alone for detection of multivessel CAD.

Coronary Angiography↗
PubMed2004

Real-time dobutamine stress myocardial contrast echocardiography for detecting coronary artery disease: correlating abnormal wall motion and disturbed perfusion.

BACKGROUND: Real-time myocardial contrast echocardiography (MCE) makes possible the simultaneous visualization of changes in perfusion imaging and wall motion. OBJECTIVES: To assess the accuracy of real-time MCE for detecting the presence and extent of coronary artery disease (CAD), and to evaluate the correlation between wall motion and myocardial perfusion by visual examination. METHODS: A total of 140 consecutive patients without resting wall motion abnormalities were screened to undergo dobutamine stress MCE with power modulation and coronary angiography. Significant coronary disease was defined by the quantification of over 50% stenosis in a major epicardial vessel. The visual identification of wall motion and myocardial perfusion abnormalities was determined by blind review. RESULTS: Eight patients were excluded due to suboptimal images (feasibility 94.3%). Myocardial contrast enhancement analysis and wall motion analysis were similar in terms of sensitivity (81.2% versus 83.5%, respectively) and specificity (76.5% versus 80.9%, respectively) in detecting the presence of CAD. Myocardial contrast enhancement analysis tended to have a greater sensitivity than wall motion analysis in detecting the ischemic extent over multiple vascular territories among patients with multiple-vessel disease (sensitivity 83.8% versus 71.4% [P=0.09], and abnormal segment length 54.7+/-21.1% versus 48.9+/-24.7% [P=0.03] for myocardial contrast enhancement and wall motion analysis, respectively). There was good concordance between the presence of myocardial ischemia and wall motion abnormality for the segment-by-segment analysis (89.7% agreement, kappa = 0.745). The correlation of the wall motion score and perfusion score at peak stress was also good (r=0.793, P=0.015). CONCLUSIONS: Dobutamine stress MCE with power modulation is similar in sensitivity and specificity to wall motion analysis for detecting the presence of CAD. However, it provides greater sensitivity in evaluating the extent of ischemia in patients with multiple-vessel disease.

Adult↗
PubMed1998

Immediate and residual changes in dorsiflexion range of motion using an ultrasound heat and stretch routine.

OBJECTIVE: With respect to increasing ankle dorsiflexion range of motion, our objective was to examine the influence, if any, of preheating the triceps surae with ultrasound before stretching. DESIGN AND SETTING: Subjects were assigned to either group A (ultrasound and stretch) or group B (stretch alone). Group A received 3-MHz ultrasound (1.5 W/cm(2), 4 times effective radiating area) for 7 minutes to the musculotendinous junction of the triceps surae before stretching. Group B rested for 7 minutes before stretching. Both groups then performed identical calf stretches for 4 minutes. Treatment for both groups was conducted at the Brigham Young University Sports Injury Research Laboratory twice daily for 5 days with at least 3 hours between procedures. We analyzed the data with a 2 x 3 x 10 factorial analysis of variance with repeated measures. A Tukey post hoc test was used to identify significant differences in range of motion. SUBJECTS: Forty college students (male = 18, female = 22, age = 20.4 +/- 2.5 years) volunteered for the study. MEASUREMENTS: Maximal ankle dorsiflexion range of motion was measured using an inclinometer before and after each treatment. RESULTS: Immediate effects were that ultrasound and stretch increased mean dorsiflexion range of motion in all sessions significantly more than stretch alone in three treatment sessions. Residual effects were that dorsiflexion range of motion increased 3 degrees in both groups after nine treatment sessions; however, neither group significantly outperformed the other. CONCLUSION: As studied, an ultrasound and stretch routine may increase immediate range of motion more than stretch alone, possibly enhancing performance in practice and competition. This increased range of motion, however, is not maintained over the long term and is not more than the range of motion gained from stretching alone. A similar study using subjects with decreased range of motion after immobilization or injury should be conducted to see if the ultrasound and stretch regimen would produce lasting range-of-motion increases.

Journal Article↗
PubMed1985

Normal and paradoxical ventricular septal motion in the dog.

Normal and paradoxical ventricular septal motions were studied in dogs, using M-mode and 2-dimensional echocardiography. Normal ventricular septal motion was evaluated, using 35 clinically healthy dogs (group I), and was compared with characteristics of septal motion measured in 12 dogs with right ventricular overload (group II) and 14 dogs with left-sided heart disease (group III). Normal ventricular septal motion consisted of a series of active and passive anterior (right cranial) and posterior (left caudal) movements that were subjectively evaluated and quantitated during segments of the cardiac cycle. Maximum excursion of the ventricular septum occurred during systole, was directed toward the left ventricle, and was related to body size. Determination of a normalized radius of septal curvature from analysis of 2-dimensional echocardiogram indicated that the septal arc formed part of a generally circular left ventricle in group I dogs. In contrast to these findings, group II dogs with right ventricular pressure and volume overloads exhibited reduced systolic septal excursion, diminished or flat septal motion, and paradoxical systolic septal motion. Normalized radius of septal curvature was significantly greater in group II dogs than in group I or group III dogs. Septal motion and radius of septal curvature in dogs comprising group III were not significantly different from normal during most phases of the cardiac cycle. Results of this study support the concept that septal motion is a reflection of overall left ventricular shape and that abnormalities in ventricular septal motion, namely flat or paradoxical septal motion, should cause the clinician to suspect right ventricular volume or pressure overload.

Animals↗
PubMed1981

[Regional wall motion of the left ventricle in congestive cardiomyopathy: in comparison with progressive muscular dystrophy of Duchenne type (author's transl)].

The features of regional wall motion abnormalities of the left ventricle were analysed in 11 patients of congestive cardiomyopathy (CCM) in comparison with 22 patients of progressive muscular dystrophy (DMD) of Duchenne type who showed an abnormal motion of the left ventricle by echocardiography. Real time two-dimensional echocardiographic study demonstrated the following results: I) In CCM, (1) only 2 or less of 11 cases preserved a normal motion in each left ventricular segment, and the depression of wall motion of the left ventricle were thought to be generalized; (2) there were 9 cases with segmental wall motion abnormalities and 3 of them demonstrated ventricular aneurysms, and (3) the localizations of the segmental abnormalities varied in each case, and there was no apparent accumulation to any segments. II) In DMD, (1) all the cases showed depressed motions and 8 of them demonstrated a ventricular aneurysm in the posterior wall of the left ventricle (LVPW), (2) while, there was no case showing ventricular aneurysm in the segments other than LVPW, and about one third of all cases showed normal motion in those segments. From these results, we concluded as follows: 1) Although the depression of a wall motion of the left ventricle was generalized in CCM, this was not always uniform and the segmental abnormalities of a wall motion were frequently observed. The localization of the most severely disturbed segment varied in each case. 2) On the other hand, in DMD, the wall motion was disturbed more frequently and more severely in LVPW than in other ventricular segments.

Adolescent↗
PubMed1980

The biological effect of continuous passive motion on the healing of full-thickness defects in articular cartilage. An experimental investigation in the rabbit.

A new concept, continuous passive motion of a synovial joint in vivo, was investigated to determine its biological effect on the healing of full-thickness articular cartilage defects that penetrate the subchondral bone of knee joints of adolescent and adult rabbits. The effect of continuous passive motion was compared with the effects of immobilization and of intermittent active motion. This investigation included assessment of 480 defects in the knees of 120 adolescent rabbits and assessment of 108 defects in the knees of twenty-seven adult rabbits. The continuous passive motion was well tolerated by these animals, whose general well-being was undisturbed. The healing of the defects at weekly intervals up to four weeks was assessed by gross examination and by an analysis of two indices of healing determined by light microscopy: (1) the nature of the reparative tissue, and (2) the degree of metachromasia of the matrix as demonstrated by toluidine-blue staining. At three weeks this assessment revealed that in the adolescent rabbits, healing of the defects by hyaline articular cartilage was present in 8 per cent of forty defects in ten animals whose knees were immobilized, in 9 per cent of forty defects in ten animals whose knees were permitted intermittent active motion, and in 52 per cent of forty defects in ten animals whose knees were managed immediately after operation by continuous passive motion. At three weeks, in the adult animals, healing of the defects by hyaline articular cartilage was present in 3 per cent of thirty-six defects in nine animals whose knees were immobilized, in 5 per cent of thirty-six defects in nine animals whose knees were permitted intermittent active motion, and in 44 per cent of thirty-six defects in nine animals whose knees were managed immediately after operation by continuous passive motion. Thus, the metaplasia of the healing tissue within the defects from undifferentiated mesenchymal tissue to hyaline articular cartilage was not only much more rapid but also much more complete with continuous passive motion than with either immobilization or intermittent active motion.

Age Factors↗
PubMed1995

Preventing patient motion during tomographic myocardial perfusion imaging.

UNLABELLED: We evaluated whether use of a device that positions and supports the upper extremities and back during tomographic myocardial perfusion imaging reduces the incidence and severity of patient motion and patient motion artifact. METHODS: We enrolled 190 patients referred for stress/redistribution myocardial perfusion imaging. All patients were imaged once with the patient support device (PSD) and once without it. Patients were randomly assigned to use the PSD either during poststress or redistribution imaging. The presence and severity of patient motion was determined by visual inspection and quantitative motion detection. The presence of reconstruction artifact due to motion was detected visually and confirmed by motion correction. RESULTS: Use of the PSD reduced the incidence of motion from 38% +/- 3.7% to 26% +/- 3.3% (p < 0.05) and reduced the amount of motion by 5.3 +/- 2.2 mm (p < 0.05). Patients who did move, moved less when using the PSD by both visual (p < 0.02) and quantitative criteria (p < 0.05). Use of the PSD reduced the incidence of reconstruction artifacts to one third of control (p < 0.05). CONCLUSION: The use of this positioning and support device during tomographic myocardial perfusion imaging reduces the incidence and severity of patient motion and motion artifact.

Artifacts↗
PubMed1994

Temporal image fractionation: rejection of motion artifacts in myocardial SPECT.

METHODS: We have developed a protocol, termed "temporal image fractionation," in which static myocardial perfusion SPECT studies are acquired as three-interval dynamic studies (three temporal frames, each consisting of a full projection set), utilizing continuous alternating detector rotation and a multi-detector camera. The frames are individually examined for motion by cine display, then summed together into a static SPECT file which is reconstructed with standard procedure. This approach offers three potential advantages in reducing or eliminating image artifacts resulting from patient or organ motion: (1) If severe motion occurs in one frame, only the remaining two are summed and reconstructed (motion-purging); (2) Alternating detector rotation reduces artifacts from mono-directional, drifting motion during acquisition (i.e., upward creep of the heart); and (3) Generally, with multiple rotations, motion is spread over a larger angular range and therefore has a lesser effect of the final reconstructed images. RESULTS: These advantages are demonstrated and quantified in this paper using clinical data (A) and simulated motion on phantom data (B and C). In the phantom experiments, fractionated images were found to be 48.9%, 35.8% and 35.9% "more similar" to the original images than nonfractionated images for simulated 1.67-cm upward creep, 1.1-cm nonreturning axial motion and 1.65-cm lateral motion, respectively. CONCLUSION: This protocol requires little extra processing and no final extra data storage compared to standard acquisition, and it has nearly eliminated instances in which a study had to be repeated due to patient motion. Step-and-shoot acquisition is not recommended in conjunction with this protocol, as it would lengthen the time necessary to obtain the same count statistics as in nonfractionated acquisition.

Artifacts↗
PubMedDate not supplied

Types of diaphragmatic motion during hepatic angiography.

To determine the types and causes of diaphragmatic motion during hepatic angiography, the authors used transarterial cut-film portography (TAP) to study movement of the diaphragm during breath-holding. Thirty-three TAP sequences were studied, and the patients' diaphragmatic motions were classified into four categories according to the distance their diaphragms moved. Results showed that the diaphragm was stationary in 33% of the TAP studies, while perpetual motion occurred in 15% of the studies, early-phase motion occurred in 12% and late-phase motion occurred in 40%. Ten sequences showed diaphragmatic motion of more than 10 mm, with eight sequences showing caudal motion and two showing cranial motion. This article discusses the cause of diaphragmatic motion during breath-holding for hepatic angiography and presents suggestions to reduce motion artifacts during the exam.

Adult↗
PubMed2006

Prospective real-time slice-by-slice motion correction for fMRI in freely moving subjects.

Subject motion is still the major source of data quality degradation in functional magnetic resonance imaging (fMRI) studies. Established methods correct motion between successive repetitions based on the acquired imaging volumes either retrospectively or prospectively. A fast, highly accurate, and prospective real-time correction method for fMRI using external optical motion tracking has been implemented. The head position is determined by means of an optical stereoscopic tracking system. The method corrects motion during the acquisition of an fMRI time series on a slice-by-slice basis by continuously updating the imaging volume position to follow the motion of the head. This method allows the measurement of fMRI data in the presence of significant motion during the acquisition of a single volume. Even without intentional motion, fMRI signal stability is maintained and higher sensitivity to detect activation is achieved without reducing specificity. With significant motion, only the proposed approach allowed detection of brain activation. The results show that the new method is superior to image-based correction methods, which fail in the case of fast or excessive motion.

Artifacts↗
PubMed2001

Role of autonomic nervous system for development and suppression of motion sickness in Suncus murinus.

To clarify the role of autonomic nervous function in motion sickness, the effect of agents that act on the autonomic nervous system on the motion stimuli-induced emesis was studied in two strains of Suncus murinus (Jic:SUN-Her and Jic:SUN-Ler) with congenitally different sensitivity to veratrine sulfate. We demonstrated significant differences between the two strains in sensitivity to motion stimuli. Isoproterenol (2.5 mg kg(-1), s.c.) significantly prolonged the latency to the first emetic episode induced by motion stimuli and significantly decreased the number of emetic episodes in Jic:SUN-Her suncus. Hexamethoium (2.0 mg kg(-1), s.c.) tended to shorten the latency in Jic:SUN-Ler. Acetylcholine (1.2 mg kg(-1), s.c.) enhanced the emetic response in Jic:SUN-Ler, but atropine (4.0 mg kg(-1), s.c.) suppressed motion stimuli-induced emetic response in Jic:SUN-Her. These results suggest that the predominance of parasympathetic nervous activity is relevant to the enhancement of motion stimuli-induced emetic response, whereas the predominance of sympathetic nervous activity suppresses motion stimuli-induced emetic response. Norepinephrine (0.8 mg kg(-1), s.c.) enhanced motion stimuli-induced emesis contrary to isoproterenol in Jic:SUN-Ler although both drugs are adrenergic agents. However, atropine pretreatment (4.0 mg kg(-1), s.c.) inhibits norepinephrine-induced emetic response. It was considered that norepinephrine-induced emetic response might be dependent on a secondary increase of parasympathetic nervous activity due to bororeflex. Moreover, the different emetic response in Jic:SUN-Her and Jic:SUN-Ler suncus to motion stimuli and drug administration mentioned above indicated that different participation of autonomic nervous activity and/or afferent information from the baroreceptor in the emetic response may exist between these animal groups.

Acetylcholine↗
PubMed2002

Motion palpation findings and self-reported low back pain in a population-based study sample.

BACKGROUND: Although the clinical usefulness of motion palpation has not been established, it is one of the most commonly used diagnostic methods by chiropractors. Notably, its sensitivity, specificity, and validity in general have not been adequately studied, and most study samples have consisted of student volunteers. OBJECTIVE: To determine the prevalence of positive motion-palpation findings (so-called fixations and spontaneous pain response) in relation to self-reported low back pain status and to determine the sensitivity and specificity of the motion-palpation technique carried out on the sacroiliac and lumbar joints. DESIGN: Study subjects were examined by 1 examiner (out of 7 possible), who was unaware of their low back pain status. Information on low back pain was then collected in a self-report questionnaire. SETTING: Research laboratory at the Odense University Hospital, Denmark. PARTICIPANTS: One hundred eighty-four twins, consisting of a subset of healthy twins taken from a panel of population-generated twins aged 19 to 42 years, made up the study sample. Examiners consisted of 7 biomechanics (chiropractic) students from the University of Southern Denmark who were proficient in motion palpation. MAIN OUTCOME MEASURES: The prevalence rates of motion palpation-determined fixations and of spontaneous pain reactions in response to motion palpation were studied in relation to anatomic area, self-reported low back pain status, and each other. RESULTS: The point period prevalence of low back pain was 14%. Fixations were found in 43% of the study sample, and 25% appeared to have a painful reaction to motion palpation. There was no logical pattern of fixations and spontaneous pain reactions in relation to the low back pain status. The sensitivity was generally low (always below 60%) for fixations and pain, whereas the specificity was higher, significantly so for pain in the mid lumbar area. There was no strong association between fixations and the examiners' interpretation of a spontaneous pain reaction in response to motion palpation. CONCLUSION: Motion palpation does not appear to be a good method to differentiate persons with or without low back pain. It is possible to dissociate the findings of fixations and those of pain reactions.

Adult↗
PubMed2002

Measurement of cadaver lumbar spine motion segment stiffness.

STUDY DESIGN: Prospective. OBJECTIVES: To measure lumbar spine motion segment stiffness and relate it to the degree of disc degeneration. SUMMARY OF BACKGROUND DATA: The association between the instability of the lumbar spine motion segment and disc degeneration remains unclear. The traditional method for determining motion segment instability at the time of decompressive surgery is a manual test performed by the surgeon. To quantify instability of the lumbar spine, a vertebrae distractor was developed in the authors' laboratory to measure motion segment stiffness by applying a defined load at a constant rate. METHODS: Lumbar stiffness was measured by subjecting cadaver lumbar spine motion segments to a constant rate flexion-traction load and recording the magnitude of the resistance to distraction versus the range of motion. Disc degeneration was measured by pressure-volume discography and by grading of disc morphology. RESULTS: Motion segment stiffness decreased with the initial stages of disc degeneration and then increased with severe disc degeneration. This measure of motion segment stiffness correlated well with a manual stiffness measure. CONCLUSIONS: The observed results follow an accepted hypothesis of motion segment instability associated with disc degeneration.

Adult↗