Slow stroke back massage: its effect on patients in a rehabilitation setting

A quasi-experimental design was used to determine the effects of three consecutive days of slow stroke back massage (SSBM) on adult patients in a rehabilitation setting. This study used the Huckstadt Touch Instrument to assess physiological and psychological responses to touch, as well as the recipients' perceptions of touch. The convenience sample comprised 24 adult patients in a rehabilitation hospital in southeastern North Carolina. Subjects' ages ranged between 52 and 88 years with a mean of 71.8 years. There was a significant decrease in systolic and diastolic blood pressure after SSBM on all 3 days. There was a statistically significant decrease in mean heart rate and mean respiratory rate on Days 1 and 3. There was no psychological change in any of the patients. Perception scores, however, indicate a positive response to SSBM. Patients perceived it as being comfortable, good, pleasant, and warm. On all occasions, their responses indicated that the intervention made them feel cared for, happy, physically relaxed, less anxious, calm, restful, and gave them a feeling of closeness with the nurse.

Reliability of lateral bending and axial rotation with validity of a new method to determine axial rotation on anteroposterior cervical radiographs

OBJECTIVE

To investigate the reliability of a new radiographic measurement of axial rotation and lateral bending on anterior-posterior cervical views by using a computer and sonic digitizer.

DESIGN

A blind, repeated-measure design was used. Anteroposterior cervicothoracic radiographs were presented to each of 3 examiners in random order. Each film was digitized, and 1 week later the films were randomized for a second run.

SETTING

Private, primary-care chiropractic clinic.

MAIN OUTCOME MEASURES

The interclass and intraclass correlation coefficients (ICC) for intraexaminer and interexaminer reliability were calculated from measurements on radiographs for determining axial rotations (Ry) and lateral bending (Rz) of C3 to T3.

RESULTS

When the new axial rotation method was applied to small rotations of a C3 plastic model, the average error was less than 1 degrees. For the calculations of axial rotation (Ry), the ICC values were in the good to excellent range. For axial rotation, the intraclass correlation coefficients were ICCs > or =0.78, and the interclass correlation coefficients were ICCs > or =0.67. For lateral flexions (Rz) of C3 to T3, all intraclass and interclass correlation coefficients were in the excellent range (ICCs > 0.87).

CONCLUSIONS

Methods of calculating axial rotations in the spine have been reported for large angles (5 degrees to 30 degrees ) but not for smaller angles. A new method for determining axial rotations of the cervical segments on AP views, based on the chord across the arc displaced by the spinous-lamina junction, had reliability (ICC values) in the good to excellent range. Compared with measured rotations of a C3 model (-5 degrees to +5 degrees ), the new method had an average error of less than 1 degrees and approximately 11.5%. The reliability for the axial rotation measurements was in the good to excellent range, and the lateral bending measurements were all in the excellent range.

Radiographic analysis of lumbar lordosis: centroid, Cobb, TRALL, and Harrison posterior tangent methods

STUDY DESIGN

Delayed, repeated measures, with three examiners each twice digitizing thirty lateral lumbar radiographs.

OBJECTIVES

To determine the reliability and clinical utility of the centroid, Cobb, tangential radiologic assessment of lumbar lordosis (TRALL), and Harrison posterior tangent line-drawing methods for analysis of lumbar lordosis.

BACKGROUND DATA

Cobb's method is commonly used for curvature analysis on lateral lumbar radiographs, whereas the centroid, TRALL, and Harrison posterior tangent methods are not widely used.

METHODS

Thirty lateral lumbar radiographs were digitized twice by each of three examiners. To evaluate reliability of determining global and segmental alignment, all four vertebral body corners of T12-S1 and the superior margin of the femur head were digitized. Angles created were segmental and global centroid, (two-line) Cobb angles, and intersections of posterior tangents. A global TRALL angle was determined. Means, standard deviations, mean absolute differences, interclass and intraclass correlation coefficients (ICC), and confidence intervals were calculated.

RESULTS

The interobserver and intraobserver reliabilities of measuring all segmental and global angles were in the high range (ICCs > 0.83). The mean absolute differences of observers' measurements were small (0.6 degrees -2.0 degrees ). Distal segmental (L4-S1) and global angles of lumbar curvature were dependent on the method of measurement.

CONCLUSIONS

All four radiographic methods had high reliability and low mean absolute differences of observers' measurements. Because it lacks a segmental analysis, the TRALL method is not recommended. The centroid, Cobb, and Harrison posterior tangent methods provide global and segmental angles. However, the centroid segmental method requires three segments and is less useful for a stability analysis.

Reliability of centroid, Cobb, and Harrison posterior tangent methods: which to choose for analysis of thoracic kyphosis

STUDY DESIGN

Thirty lateral thoracic radiographs were digitized twice by each of the three examiners.

OBJECTIVES

To determine the reliability of the centroid, Cobb, and Harrison posterior tangent methods when applied to analysis of thoracic kyphosis.

BACKGROUND DATA

Reliability studies on measurements of thoracic kyphosis are rare.

METHODS

Blind, repeated-measures design was used. Thirty lateral thoracic radiographs were digitized twice by each of three examiners. To evaluate reliability of determining global and segmental alignment, vertebral bodies of T1-T12 were digitized. Centroids at the intersection of vertebral body diagonals and tangents to posterior vertebral bodies were constructed by computer. Also the computer constructed global and segmental centroid angles, Cobb angles (two-line method), and posterior tangent intersection angles from T1 to T12. Interclass and Intraclass correlation coefficients for these data were calculated and interpreted.

RESULTS

From the points selected by examiners, all three methods have similar high ICC values for the global angles (> 0.94). For the segmental angles, the interobserver and intraobserver reliability is also very similar for all three methods, with ICCs in the good and excellent ranges (0.59-0.75 and 0.75-1.0, respectively). The mean absolute differences of observers' measurements are low, similar, and in the range of 0.9 degrees to 2.5 degrees.

CONCLUSIONS

The centroid, two-line Cobb, and Harrison posterior tangent methods, when applied to measurements of kyphosis, are all reliable and have similar small error ranges. The centroid method does not give an accurate segmental analysis, uses more points and more time in clinical applications, and results in smaller angles of total kyphosis than the Cobb or posterior tangent methods. The posterior tangents are the slopes along the curve.

A trial of recombinant human granulocyte colony stimulating factor for the treatment of very low birthweight infants with presumed sepsis and neutropenia

OBJECTIVES

The primary objective was to investigate the safety of recombinant human granulocyte colony stimulating factor (rhG-CSF) for the treatment of very low birthweight infants (VLBW) with sepsis and relative neutropenia, specifically with regard to worsening of respiratory distress and thrombocytopenia and all cause mortality. Secondary objectives were to evaluate duration of ventilation, intensive care, and antibiotic use as markers of efficacy.

DESIGN

Neonates (< or = 28 days) in intensive care, with birth weights of 500-1500 g, absolute neutrophil count (ANC) of < or = 5 x 10(9)/l, and clinical evidence of sepsis, were randomly assigned to receive either rhG-CSF (10 microg/kg/day) administered intravenously (n = 13), or placebo (n = 15) for a maximum of 14 days, in addition to standard treatment and antibiotics. All adverse events, oxygenation index, incidence of thrombocytopenia, all cause mortality, duration of ventilation, intensive care and antibiotic treatment, and ANC recovery were compared between the two groups.

RESULTS

Adverse events and oxygenation index were not increased by, and thrombocytopenia was not attributable to, treatment with rhG-CSF. At 6 and 12 months postmenstrual age, there were significantly fewer deaths in the group receiving rhG-CSF (1/13 v 7/15; p < or = 0.038). There was a non-significant trend towards a reduction in duration of ventilation, intensive care, and antibiotic use in the rhG-CSF group. There was a significantly more rapid increase in ANC in the rhG-CSF treated babies (p < 0.001).

CONCLUSIONS

In a small randomised placebo controlled trial in a highly selected group of neonates, adjuvant treatment with rhG-CSF increased ANC rapidly, and no treatment related adverse events were identified. Mortality at 6 and 12 months postmenstrual age was significantly lower in the treatment group. A large trial investigating efficacy in a similar group of neonates is warranted.

Emergence of domestically acquired ceftriaxone-resistant Salmonella infections associated with AmpC beta-lactamase

CONTEXT

Ceftriaxone, an expanded-spectrum cephalosporin, is an antimicrobial agent commonly used to treat severe Salmonella infections, especially in children. Ceftriaxone-resistant Salmonella infections have recently been reported in the United States, but the extent of the problem is unknown.

OBJECTIVES

To summarize national surveillance data for ceftriaxone-resistant Salmonella infections in the United States and to describe mechanisms of resistance.

DESIGN AND SETTING

Case series and laboratory evaluation of human isolates submitted to the Centers for Disease Control and Prevention from 17 state and community health departments participating in the National Antimicrobial Resistance Monitoring System (NARMS) for enteric bacteria between 1996 and 1998.

PATIENTS

Patients with ceftriaxone-resistant Salmonella infections between 1996 and 1998 were interviewed and isolates with decreased ceftriaxone susceptibility were further characterized.

MAIN OUTCOME MEASURES

Exposures and illness outcomes, mechanisms of resistance.

RESULTS

The prevalence of ceftriaxone-resistant Salmonella was 0.1% (1 of 1326) in 1996, 0.4% (5 of 1301) in 1997, and 0.5% (7 of 1466) in 1998. Ten (77%) of the 13 patients with ceftriaxone-resistant infections were aged 18 years or younger. The patients lived in 8 states (California, Colorado, Kansas, Massachusetts, Maryland, Minnesota, New York, and Oregon). Nine (82%) of 11 patients interviewed did not take antimicrobial agents and 10 (91%) did not travel outside the United States before illness onset. Twelve of the 15 Salmonella isolates with ceftriaxone minimum inhibitory concentrations of 16 microg/mL or higher were serotype Typhimurium but these isolates had different pulsed-field gel electrophoresis patterns. Thirteen of these 15 isolates collected between 1996 and 1998 were positive for a 631-base pair polymerase chain reaction product obtained by using primers specific for the ampC gene of Citrobacter freundii.

CONCLUSIONS

Domestically acquired ceftriaxone-resistant Salmonella has emerged in the United States. Most ceftriaxone-resistant Salmonella isolates had similar AmpC plasmid-mediated resistance.

Competition between the replication initiator DnaA and the sequestration factor SeqA for binding to the hemimethylated chromosomal origin of E. coli in vitro

BACKGROUND

Following replication initiation, the replication origin (oriC) in Escherichia coli enters a hemimethylated state at Dam methylation sites which are recognized by the SeqA protein. SeqA binds preferentially to hemimethylated GATC sequences of DNA in vitro. SeqA is essential for the synchronous initiation of chromosome replication from oriC copies in vivo.

RESULTS

We show that: (i) purified SeqA binds AT-rich and 13-mers regions and two DnaA boxes, R1 and M, of hemimethylated oriC. (ii) SeqA inhibits the in vitro replication of a hemimethylated oriC plasmid more efficiently than the fully methylated, (iii) SeqA inhibits competitive binding of DnaA protein to the regions of the hemimethylated oriC plasmid, explaining the mechanism of its inhibitory effect. The inhibition of DnaA binding by SeqA also occurs efficiently on a small hemimethylated oriC fragment containing both R1 and M DnaA boxes, but not the 13-mer region.

CONCLUSIONS

SeqA binds strongly the long region from the AT-rich region to the M DnaA box of the hemimethylated oriC DNA and releases DnaA molecules from the long region.

Chiropractic biophysics digitized radiographic mensuration analysis of the anteroposterior cervicothoracic view: a reliability study

OBJECTIVE

To investigate the reliability of a radiographic measurement procedure that uses a computer and sonic digitizer to determine projected spinal displacements from an ideal, normal position.

DESIGN

A blind, repeated-measure design was used. Anteroposterior cervicothoracic spine radiographs were presented in random order to each of 3 examiners. Each film was digitized, and the films were randomized for a second examination.

SETTING

Private, primary care chiropractic clinic.

MAIN OUTCOME MEASURES

Intraclass correlation coefficients for intraexaminer and interexaminer reliability for measures on radiographs comparing the perpendicular distance (T(x)) from a vertical axis line drawn through the center of T4 and the center of C2, the linear distance (vertebra(apex)) from the center of the vertebra most displaced from a line connecting the centers of C2 and T4, the angle (Rz) formed by the intersection of the vertical axis line and the upper thoracic line, and the angle of intersection (CDA) between the upper thoracic line and the cervical line.

RESULTS

Intraexaminer reliability for T(x) distance was 0.99 to 1.00, with confidence intervals from 0.98-1.00; for vertebra(apex) was 0.96 to 0.97, with confidence intervals from 0.92-0.98; for Rz was 0.94 to 0.98, with confidence intervals from 0. 89-0.99; and for CDA was 0.92 to 0.95, with confidence intervals from 0.84-0.97. Interexaminer reliabilities for the 3 examiners ranged from 0.97 to 0.99.

CONCLUSIONS

Measures similar to those described in this study are commonly used to quantify and categorize spinal displacements from true vertical alignment (i.e., scoliosis measurements). Intraclass correlation coefficient values >0.70 are considered accurate enough for use in clinical and research applications. The measures tested here would fit within these guidelines of reliability. Establishing reliability is an important first step in evaluating these measures so that future studies of validity may be undertaken.

Cobb method or Harrison posterior tangent method: which to choose for lateral cervical radiographic analysis

STUDY DESIGN

Thirty lateral cervical radiographs were digitized twice by three examiners to compare reliability of the Cobb and posterior tangent methods.

OBJECTIVES

To determine the reliability of the Cobb and Harrison posterior tangent methods and to compare and contrast these two methods.

SUMMARY OF BACKGROUND DATA

Cobb's method is commonly used on both anteroposterior and lateral radiographs, whereas the posterior tangent method is not widely used.

METHODS

A blind, repeated-measures design was used. Thirty lateral cervical radiographs were digitized twice by each of three examiners. To evaluate reliability of determining global and segmental alignment, vertebral bodies of C1-T1 were digitized. Angles created were two global two-line Cobb angles (C1-C7 and C2-C7), segmental Cobb angles from C2 to C7, and posterior tangents drawn at each posterior vertebral body margin. Cobb's method and the posterior tangent method are compared and contrasted with these data.

RESULTS

Of 34 intraclass and interclass correlation coefficients, 28 were in the high range (>0.7), and 6 were in the good range (0.6-0.7). The Cobb method at C1-C7 overestimated the cervical curvature (-54 degrees ) and, at C2-C7 it underestimated the cervical curve (-17 degrees ), whereas the posterior tangents were the slopes along the curve (-26 degrees from C2 to C7). The inferior vertebral endplates and posterior body margins did not meet at 90 degrees (C2: 105 degrees +/- 5.2 degrees, C3: 99.7 degrees +/- 5.2 degrees, C4: 99.9 degrees +/- 5.8 degrees, C5: 96.1 degrees +/- 4.5 degrees, C6: 97.0 degrees +/- 3.8 degrees, C7: 95.4 degrees +/- 4.1 degrees ), which caused the segmental Cobb angles to underestimate lordosis at C2-C3, C4-C5, and C6-C7.

CONCLUSIONS

Although both methods are reliable with the majority of correlation coefficients in the high range (ICC > 0.7), from the literature, the posterior tangent method has a smaller standard error of measurement than four-line Cobb methods. Global Cobb angles compare only the ends of the cervical curve and cannot delineate what happens to the curve internally. Posterior tangents are the slopes along the curve and can provide an analysis of any buckled areas of the cervical curve. The posterior tangent method is part of an engineering analysis (first derivative) and more accurately depicts cervical curvature than the Cobb method.

Retrospective analysis of viral load and SIV antibody responses in rhesus macaques infected with pathogenic SIV: predictive value for disease progression

The prognostic significance of SIV plasma viral load in macaques has not been well established, primarily owing to the small numbers of animals in experimental groups. In addition, many investigators have noted that animals that fail to develop an anti-SIV humoral response develop disease rapidly. To establish the prognostic significance of viral load and seroconversion, we retrospectively analyzed the plasma viral load and serology data from 74 rhesus macaques infected with SIVmac. Viral load was analyzed at three time points: in the peak (days 7-21), acute (days 30-55), and chronic (days 80-100) periods postinfection. High viral load in the peak and acute phases was associated with more rapid development of disease (p = 0.0086, p = 0.0004, respectively). We defined clinical outcome as rapid ( <1 year) or slow (> or =1 year) progression. When peak and acute viral loads were analyzed together, acute viral load was more strongly associated with rapid progression (p = 0.03). Slow progression was strongly associated with chronic viral loads below the median of 3.47 x 10(5) RNA copies/ml. Despite having preexisting anti-SIV antibodies, 7 of 23 vaccinated animals were rapid progressors. All unvaccinated animals that mounted a humoral response to SIV were slow progressors. Animals that received a formalin-fixed, microencapsulated SIV vaccine prior to infection had lower peak viral loads than unvaccinated animals (p = 0.0005), but developed disease at the same rate. Overall, in naive animals, viral load is an important prognostic indicator of the disease progression rate. We found that viral load measured during the chronic phase (days 80-100) of infection was most closely associated with disease progression. We also found that a formalin-fixed, microencapuslated SIV vaccine reduced viral load without affecting clinical outcome. This latter finding may have implications for the evaluation of HIV-1 human vaccine trials.

Borrelia burgdorferi-specific immune complexes in acute Lyme disease

CONTEXT

Diagnosis of infection with Borrelia burgdorferi, the cause of Lyme disease (LD), has been impeded by the lack of effective assays to detect active infection.

OBJECTIVE

To determine whether B. burgdorferi-specific immune complexes are detectable during active infection in LD.

DESIGN, SETTING, AND PATIENTS

Cross-sectional analysis of serum samples from 168 patients fulfilling Centers for Disease Control and Prevention surveillance criteria for LD and 145 healthy and other disease controls conducted over 8 years. Tests were performed blinded.

MAIN OUTCOME MEASURE

Detection of B. burgdorferi immune complexes by enzyme-linked immunosorbent assay and Western blot.

RESULTS

The B. burgdorferi immune complexes were found in 25 of 26 patients with early seronegative erythema migrans (EM) LD; 105 of 107 patients with seropositive EM LD; 6 of 10 samples that were seronegative [corrected] with culture-positive EM; 0 of 12 patients who were treated and recovered from LD; and 13 of 13 patients with neurologic LD without EM. Among 147 controls, B. burgdorferi immune complex was found in 0 of 50 healthy individuals; 0 of 40 patients with persistent fatigue; 0 of 7 individuals with frequent tick exposure; and 2 of 50 patients with other diseases.

CONCLUSION

These data suggest that B. burgdorferi immune complex formation is a common process in active LD. Analysis of the B. burgdorferi immune complexes by a simple technique has the potential to support or exclude a diagnosis of early as well as active LD infection.

Effect of human immunodeficiency virus infection on serum beta2-microglobulin levels in pregnant women

OBJECTIVE

To assess serum beta2-microglobulin levels in human immunodeficiency virus (HIV)-infected and uninfected pregnant women, variations of serum beta2-microglobulin levels during pregnancy and postpartum, factors that might influence beta2-microglobulin levels in pregnant women, and the association between beta2-microglobulin and perinatal HIV-1 transmission.

METHODS

We assayed 374 stored (-70C) serum samples from pregnant women enrolled in the Newark perinatal HIV-1-transmission study and 18 nonpregnant women for beta2-microglobulin using a microparticulate enzyme immunoassay. The Student t test, Wilcoxon rank test, binomial test, and Spearman correlation coefficient were used for statistical analysis, with P < .05 considered statistically significant. A linear regression model was used to assess the effect of independent variables on serum beta2-microglobulin levels.

RESULTS

There were no significant differences (P = .16) in serum beta2-microglobulin levels between pregnant and nonpregnant HIV-negative women (1.07+/-0.35 versus 0.99+/-0.18 mg/L). Beta2-Microglobulin levels did not vary throughout pregnancy and postpartum, irrespective of HIV serostatus. Substance abuse did not alter beta2-microglobulin levels. Human immunodeficiency virus infection caused significant increases of this surrogate marker, but it could not discriminate among disease stages. Beta2-Microglobulin levels at delivery were lower among women who delivered HIV-infected infants.

CONCLUSION

Human immunodeficiency virus infection was associated with increased serum beta2-microglobulin levels in pregnant women and was the most significant correlate of increases of that marker. Pregnancy and substance use during pregnancy did not influence levels of serum beta2-microglobulin significantly.

Chiropractic biophysics digitized radiographic mensuration analysis of the anteroposterior lumbopelvic view: a reliability study

OBJECTIVE

To investigate the reliability of a radiographic measurement procedure that uses a computer and sonic digitizer to determine projected spinal displacements from an ideal normal position.

DESIGN

A blind, repeated-measure design was used. Anteroposterior lumbopelvic radiographs were presented to each of 3 examiners in random order. Each film was digitized, and the films were randomized for a second run.

SETTING

Private, primary-care chiropractic clinic.

MAIN OUTCOME MEASURES

The angle of the sacral base in comparison to a true horizontal line (horizontal base angle), lumbodorsal angle, lumbosacral angle, and the thoracic translational displacement from true vertical determined as the perpendicular distance from the center of T12 to a vertical axis line drawn from the center of the S1 spinous process cephalad and parallel to the lateral edge of the x-ray film.

RESULTS

Intraexaminer reliability for the (a) horizontal base angle was .72 to .94, with confidence intervals included in the range of .52 to .97; (b) lumbodorsal angle was .90 to .96, with confidence intervals in the range of .82 to .98; (c) lumbosacral angle was .84 to .96, with confidence intervals in the range of .72 to .98, and (d) thoracic translational displacement from vertical was .95 to.97, with confidence intervals included in the range of .91 to .99. Interexaminer reliability for the three examiners ranged from .71 to .97.

CONCLUSIONS

Measures similar to those described in this study are commonly used to measure and categorize spinal displacements from true vertical alignment (ie, scoliosis measurements). Most patient assessment methods used in chiropractic have poor or unknown reliability. The one possible exception to this rule is spinal displacement analysis performed on radiographs. In chiropractic, intraclass correlation coefficients values greater than .70 are considered accurate enough for use in clinical and research applications. The measures tested here would fit within these guidelines of reliability. Establishing reliability is an important first step in evaluating these measures so that future studies of validity may be undertaken.

Mastery of fundamental motor skills among New South Wales school students: prevalence and sociodemographic distribution

Mastery of fundamental motor skills among children and adolescents is a potentially important contribution to satisfying participation in sports, games and other physical activities and may enhance the development of an active lifestyle. However, few attempts have been made to determine the prevalence of fundamental motor skill mastery among young Australians. The NSW Schools Fitness and Physical Activity Survey, 1997 (N = 5518) randomly selected schools proportionally from all three education sectors and selected students in Years 4, 6, 8 and 10. Performance on six fundamental motor skills (run, vertical jump, catch, overhand throw, forehand strike and kick) was assessed qualitatively. The prevalence of mastery and near mastery of each skill and mastery of each skill component is reported for boys and girls in each school year. The findings indicate that the prevalence of mastery and near mastery of each of the fundamental motor skills was generally low. There were no differences between students from urban or rural schools and the prevalence of skill mastery was directly associated with socioeconomic status more consistently among girls than among boys. Greater curriculum time and resourcing and training of teachers is required to increase the proportion of students who have mastered the skills fundamental to common sports, games and other physical activities.

Experimental removal of sexual selection reverses intersexual antagonistic coevolution and removes a reproductive load

Although sexual selection can provide benefits to both sexes, it also can be costly because of expanded opportunities for intersexual conflict. We evaluated the role of sexual selection in a naturally promiscuous species, Drosophila melanogaster. In two replicate populations, sexual selection was removed through enforced monogamous mating with random mate assignment or retained in promiscuous controls. Monogamous mating constrains the reproductive success of mates to be identical, thereby converting prior conflicts between mates into opportunities for mutualism. Random mate assignment removes the opportunity for females to choose beneficial qualities in their mate. The mating treatments were maintained for 47 generations, and evolution was allowed to proceed naturally within the parameters of the design. In the monogamous populations, males evolved to be less harmful to their mates, and females evolved to be less resistant to male-induced harm. The monogamous populations also evolved a greater net reproductive rate than their promiscuous controls. These results indicate a potentially widespread cost of sexual selection caused by conflicts inherent to promiscuity.

High-pressure, rapid-inflation pneumatic compression improves venous hemodynamics in healthy volunteers and patients who are post-thrombotic

PURPOSE

Deep vein thrombosis (DVT) is a preventable cause of morbidity and mortality in patients who are hospitalized. An important part of the mechanism of DVT prophylaxis with intermittent pneumatic compression (IPC) is reduced venous stasis with increased velocity of venous return. The conventional methods of IPC use low pressure and slow inflation of the air bladder on the leg to augment venous return. Recently, compression devices have been designed that produce high pressure and rapid inflation of air cuffs on the plantar plexus of the foot and the calf. The purpose of this study is to evaluate the venous velocity response to high-pressure, rapid-inflation compression devices versus standard, low-pressure, slow-inflation compression devices in healthy volunteers and patients with severe post-thrombotic venous disease.

METHOD

Twenty-two lower extremities from healthy volunteers and 11 lower extremities from patients with class 4 to class 6 post-thrombotic chronic venous insufficiency were studied. With duplex ultrasound scanning (ATL-Ultramark 9, Advanced Tech Laboratory, Bothell, Wash), acute DVT was excluded before subject evaluation. Venous velocities were monitored after the application of each of five IPC devices, with all the patients in the supine position. Three high-pressure, rapid-compression devices and two standard, low-pressure, slow-inflation compression devices were applied in a random sequence. Maximal venous velocities were obtained at the common femoral vein and the popliteal vein for all the devices and were recorded as the mean peak velocity of three compression cycles and compared with baseline velocities.

RESULTS

The baseline venous velocities were higher in the femoral veins than in the popliteal veins in both the volunteers and the post-thrombotic subjects. Standard and high-pressure, rapid-inflation compression significantly increased the popliteal and femoral vein velocities in healthy and post-thrombotic subjects. High-pressure, rapid-inflation compression produced significantly higher maximal venous velocities in the popliteal and femoral veins in both healthy volunteers and patients who were post-thrombotic as compared with standard compression. Compared with the healthy volunteers, the patients who were post-thrombotic had a significantly attenuated velocity response at both the popliteal and the femoral vein levels.

CONCLUSION

High-pressure, rapid-inflation pneumatic compression increases popliteal and femoral vein velocity as compared with standard, low-pressure, slow-inflation pneumatic compression. Patients with post-thrombotic venous disease have a compromised hemodynamic response to all IPC devices. However, an increased velocity response to the high-pressure, rapid-inflation compression device is preserved. High-pressure, rapid-inflation pneumatic compression may offer additional protection from thrombotic complications on the basis of an improved hemodynamic response, both in healthy volunteers and in patients who were post-thrombotic.

Elliptical modeling of the sagittal lumbar lordosis and segmental rotation angles as a method to discriminate between normal and low back pain subjects

Clinical significance of lumbar lordosis has not been agreed on. Our purpose is to compare lordotic measurements of normal and pain subjects and to test the validity of a new anthropometric model of lumbar curvatures. Digitized radiographic points (body corners) from standing lateral lumbar radiographs were modeled with ellipses in a least-squares method and were used to create segmental angles, a global angle at L1-L5, a Cobb angle from T12 to S1, Ferguson's sacral base angle, and an angle of pelvic tilt. Fifty normal subjects were matched in age, sex, weight, and height with 50 acute pain subjects, 50 chronic pain subjects, and 24 pain subjects with radiographic abnormalities. Of 11 angles, 2 distances, and 2 ratios, statistical analysis was significantly different across groups for 12 of these measurements, with the alternative hypotheses accepted for the other 3 measurements. The lordosis of both normal and low back pain subjects can be successfully modeled with a portion (approximately 86 degrees) of an ellipse, but with different major and minor axis ratios. The normal group's average elliptic lordosis has the smallest least-squares error, approximately 1 mm per digitized point, with (minor axis)/(major axis) ratio = 0.39, L1-L5 global angle = 40 degrees, and Cobb angle = 65 degrees. The chronic and radiographic abnormalities pain groups have an elongated ellipse with hypolordosis, reduced L1-L5 global angle = 29.6-35 degrees, reduced Cobb angle = 57-58 degrees, and elliptic axis ratio = 0.27-0.30. The acute pain group is hyperlordotic with the largest L1-L5 global angle, largest Cobb angle = 70 degrees, largest Ferguson's angle, and largest pelvic tilt angle.

Further analysis of the reliability of the posterior tangent lateral lumbar radiographic mensuration procedure: concurrent validity of computer-aided X-ray digitization

OBJECTIVE

To investigate the reliability of a specific method of radiographic analysis of the geometric configuration of the lumbopelvic spine in the sagittal plane, and to investigate the concurrent validity of a computer-aided digitization procedure designed to replace the more tedious and time-consuming manual measurement process.

DESIGN

A blind, repeated-measures design was used. The results of radiographic measures derived through the traditional manual marking method were compared with measures derived by computer-aided digitization of lateral lumbopelvic radiographs.

SETTING

Private chiropractic clinic.

MAIN OUTCOME MEASURES

Pearson's product-moment correlation coefficients, paired sample t tests and intraclass correlation co-efficients (ICC) were used to examine intraexaminer reliability, and repeated measures of analysis of variance were used to examine interexaminer reliability for relative rotation angles for T12-L1, L1-L2, L2-L3, L3-L4, L4-L5, L5-S1, overall lordosis measurement [absolute rotation angle (ARA)] from L1-L5 and Cobb angle of overall lordosis measured from the inferior surface of T12 to the superior surface of S1, Ferguson's sacral base angle to horizontal, angle of pelvic tilt (arcuate angle) to horizontal and anteroposterior thoracic translation (Sz) in millimeters.

RESULTS

ICC estimates for intraexaminer reliability were in the range of 0.96-0.98 for the L1-L5 ARA, a range of 0.87-0.99 for the arcuate angle measurement, 0.83-0.94 for the Ferguson's angle measurement, 0.88-0.95 for the Cobb angle measurement from the inferior surface of T12 compared with the superior surface of S1 and 0.98-1.00 for the translation measurement of the lower thoracic spine to S1 (Sz). The intersegmental measurement's (T12-L1, L1-L2, L2-L3, L3-L4, L4-L5, L5-S1) correlations ranged from a low of 0.55 to a high of 0.97. Examination of these findings suggests that the reliability for the three doctors is acceptable with only the T12-L1 intersegmental measure falling below 0.70 for the least experienced examiner. Average ICC of interexaminer reliability for manual and computer-aided digitizing examiners were the following: 0.96 for the L1-L5 ARA; 0.84 for the arcuate angle measurement; 0.82 for the Ferguson's angle measurement; 0.88 for the Cobb angle measurement; 1.00 for the Sz translation measurement; and values of 0.65, 0.73, 0.74, 0.75, 0.89 and 0.81 for relative rotation angle measurements T12-L1, L1-L2, L2-L3, L3-L4, L4-L5 and L5-S1, respectively.

CONCLUSION

The data tend to support the reliability of this method of radiographic analysis of the geometric configuration of the lumbopelvic spine as viewed on lateral lumbopelvic radiographs. The additional data presented here tend to support the concurrent validity of the computer-aided digitization method of analysis inasmuch as the measures determined by the digitizing examiners are essentially identical to those determined by the manual method plus or minus the average standard error of measure of each value.

Quantitative determination of surface antibody binding capacities of immune subsets present in peripheral blood of healthy adult donors

The objective of this study was to quantitate the antibody binding capacity (ABC) of CD3, CD4, CD8, CD16, and CD19 on lymphocytes and CD4 on monocytes from healthy adult donors. Peripheral blood was collected over three consecutive days and repeated in the same format two weeks later for comparison to initial measurements. Immune subsets were labeled by direct single or two-color staining in whole blood followed by lysis of erythrocytes. Fluorescence intensity measurements were made by carefully calibrating the flow cytometer and then measuring the intensity of monoclonal antibody staining on labeled cells and on Quantum Simply Cellular Microbeads. The effect of paraformaldehyde fixation on intensity measurements and coefficient of variation of thirty replicates for each phenotype were also studied. We found a small change in calculated ABC following overnight fixation with a greater change following 48 h of fixation prior to flow cytometric analysis. We found excellent precision could be achieved for measuring the ABC of most markers with some improvement desirable for expression of CD4 on monocytes and CD16+ lymphocytes. Between donors we found a high-low range of CD3+ = 134,349-45,905; CD4+ (lymphocytes) = 54,174-36,106; CD4+ (monocytes) = 9,246-3094; CD8+ = 268,868-190,622; CD3+CD8+ = 269,858-212,024; CD16+ = 38,307-336; and CD19+ = 25,252-11,689. For the total donor group, the observations at week 1 and week 2 were not significantly different (alpha = .05) for any of the immunophenotypes we studied. The data presented here continue to show that it is possible to perform quantitative intensity measurements of immune subsets when performing immunophenotyping studies.

Comparisons of lordotic cervical spine curvatures to a theoretical ideal model of the static sagittal cervical spine

STUDY DESIGN

Measurements from lateral cervical radiographs of randomly selected patients are compared with two proposed ideal models.

OBJECTIVES

To evaluate lordotic cervical curvatures from a large population base, to provide a geometric sagittal cervical spine model, and to test the validity of the model to predict measured angles and distances. Averages of ranges and normal values for cervical lordosis under conditions of static equilibrium are sought.

SUMMARY OF BACKGROUND DATA

Seven angles and three distances were taken from 400 randomly selected lateral cervical radiographs of patients at a private clinic.

METHODS

The radiographic measurements are compared with predicted values from our geometric sagittal cervical spine model and the Delmas ideal cervical model.

RESULTS

Values were predicted successfully by the geometric model with an average error of 5% compared with the radiographic measurements. The range of lordosis, measured at the posterior of C2 and C7, was 16.5-66 degrees, with a mean of 34 degrees. The average height-to-length ratio for the cervical spine was 0.97.

CONCLUSIONS

Predicted values from the geometric model were comparable with the measurements of the relative rotation angles at each vertebral interspace, absolute rotation angles from C2 to C7, and height-to-length ratios. A cervical lordosis of 34 degrees and a height-to-length ratio of 0.97 are suggested for clinical and theoretical outcomes.

Intra- and interexaminer reliability of the chiropractic biophysics lateral lumbar radiographic mensuration procedure

OBJECTIVE

To determine the intra- and interexaminer reliability of a specific method of mensuration commonly used to evaluate the positional configuration of the lumbopelvic spine viewed on lateral lumbar radiographs.

DESIGN

A blind, repeated-measures design was used. Lateral lumbopelvic radiographs were presented to each of three examiners in random order. Each film was marked and measurements were recorded. The films were cleaned of all markings and randomized again for a second run by each examiner. Each examiner's measurements were unavailable to the other examiners.

SETTING

Private, primary-care chiropractic clinic.

MAIN OUTCOME MEASURES

Anterior/posterior thoracic translation in millimeters, Ferguson's sacral-plane angle to horizontal, arcuate line angle to horizontal, L1 to L5 absolute rotation angle and four relative rotation angles for L1-L2, L2-L3, L3-L4 and L4-L5. Intra- and interrelibility of the three radiographic examiners were analyzed.

RESULTS

Intraexaminer reliability for (a) L1-L5 absolute rotation angle was .98, with confidence intervals included in the range of 0.95-0.99, (b) anterior/posterior thorax translation [+/- Sz] was .97-.99, with confidence intervals included in the range of 0.94-1.00, (c) arcuate angle (AA) .40-.81, with confidence intervals included in the range of 0.07-0.90, (d) Ferguson's angle (FA) was .91-.97, with confidence intervals included in the range of 0.82-0.98, (e) relative rotation angle reliability ranges were L1-L2, .84-.94; L2-L3, .80-.85; L3-L4, .78-.89; L4-L5, .87-.92. Interexaminer reliabilities for the three examiners ranged from .66-.98.

CONCLUSION

With the exception of the arcuate angle measurement, the reliabilities for all other measurements were at least .78. Those measurements with reliabilities approaching .80 or better would be considered accurate enough for use in future clinical studies. The arcuate angle measurement may have been least reliable because of the subjective nature of the method of affixing a best-fit line to a radiographic landmark that often takes on the appearance of a mild curvature. Establishing reliability is an important first step toward evaluating these and other similar radiographic measurements that have yet to be examined for their validity.