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Problem: Recurrent pregnancy loss (RPL) affects 2-4% of couples, and remains largely unexplained. Recent studies have examined the role of cytokines in the maintenance of normal pregnancy, which is linked with an increased expression of Th2 cytokines. Overexpression of Th1 cytokines is associated with RPL. Knowing that functional polymorphisms exist for certain cytokines, it has therefore been suggested that women with RPL may have a genetic predisposition to overexpress Th1 cytokines., Method of Study: The genes for interleukin-1 beta (IL-1beta) and tumor necrosis factor alpha (TNF-alpha) carry functional gene polymorphisms. In both cases these are biallelic polymorphisms that can be detected by polymerase chain reaction followed by restriction fragment length polymorphism. The aim of this pilot study was to assess whether carriage of the rarer alleles (TNF*2 and IL-1B*2) could act as independent risk factors in recurrent miscarriage., Results: We found an increased incidence in the carriage of TNF*2, more pronounced in those women with two or more miscarriages. Carriage of the IL-1B*2 either alone or in association with TNF*2 was not associated with recurrent miscarriage., Conclusion: There may be a role for these cytokine gene polymorphisms in RPL.

The year under review has seen the first molecular characterisation, with proof of functionality, of Golgi membrane-bound glycosyltransferase enzymes catalysing the synthesis of non-cellulosic plant cell-wall polysaccharides.

Pregnancy-related increase in ligament laxity may cause joint instability. The purpose of this study was two-fold: 1) to assess knee laxity changes during pregnancy and 2) to evaluate the effect of exercise on knee laxity due to a typical prenatal fitness program. The subjects were healthy pregnant women. One group (N = 27) participated in exercise classes designed according to national guidelines. The second group (N = 38) was more sedentary. A clinical arthrometer, KT-1000, was used, and anterior and posterior drawer tests were performed. The results were added and averaged for the two knees. Laxity was constant in the second half of pregnancy and had significantly decreased by 14% 4 months after birth. No influence of parity or exercise was detected. The exercise program employing minimal to moderate weight bearing did not result in any measurable increases in knee laxity and, therefore, appears to be appropriate with regard to knee stability. These results should not, however, be extended to different types of exercise programs without additional research.

Unlabelled: Research has shown that diagnostic quality images for most teleradiology applications requires a sophisticated telemedicine system and access to a large amount of bandwidth. While the ideal standards have been set by those involved in evaluating teleradiology, these standards are impractical for many small rural health centers which deliver routine trauma care. While there is no disagreement about the ultimate need for this level of teleradiology support, the purpose of this research was to determine whether Orthopedists would be able to read plain radiographs of orthopedic trauma injuries using a desktop teleradiology system in support of rural trauma care., Method: Two radiology residents and two orthopedic residents viewed forty radiographs, twenty through a desktop teleradiology system and twenty in person. Diagnostic findings and certainty of diagnosis were recorded., Findings: There was no statistically significant difference between modalities in orthopedic residents' ability to correctly diagnose orthopedic trauma injuries. Further, for those instances when the diagnosis was imprecise, the residents were aware of their inability to make an accurate diagnosis., Conclusion: Although the study was relatively limited and further research needs to be done, the use of desktop teleradiology in support of rural orthopedic trauma consultation is a promising alternative to the more expensive forms of telemedicine technology.

This study used computed tomography (CT) imaging to determine in vivo mass, center of mass (CM), and moments of inertia (Icm) about the CM of discrete segments of the human torso. Four subjects, two males and two females, underwent serial transverse CT scans that were collected at 1-cm intervals for the full length of the trunk. The pixel intensity values of transverse images were correlated to tissue densities, thereby allowing trunk section mass properties to be calculated. The percentage of body mass observed by vertebral levels ranged from 1.1% at T1 to 2.6% at L5. The masses of the upper, middle, and lower trunk segments as percentages of body mass were estimated to be 18.5, 12.2, and 10.7%, respectively. The whole trunk mass was estimated to comprise 41.6% of the total body mass. Transverse vertebral CM values were found to lie anterior to their respective vertebral centroids by up to 5.0 cm in the lower thoracic region. For the upper, middle, and lower trunk segments, the average CM positions were found to be 25.9, 62.5, and 86.9% of the distance from the superior to inferior ends of the trunk. The upper and middle trunk CMs corresponded to approximately 4.0 cm anterior to T7/T8 vertebral centroid levels and 1.0 cm anterior to L3/L4 vertebral centroid levels, respectively. For the whole trunk, the CM was 52.7% of the distance from the xiphoid process and approximately 2.0 cm anterior to L1/L2 vertebral centroid levels. Variations in CM and Icm values were observed between subject, but these were within the range of previous reports of body segment parameters. Differences from previous studies were attributable to variations in boundary definitions, measurement techniques, population groups, and body states (live versus cadaver) examined. The disparity between previous findings and findings of this study emphasizes the need to better define the segmental properties of the trunk so that improved biomechanical representation of the body can be achieved.

The purpose of this study was to evaluate the segmental parameters of the human trunk of males in vivo using magnetic resonance imaging (MRI). In addition, the efficacy of volumetric estimation and existing prediction formulas to produce segmental properties similar to those produced by MRI was evaluated. As opposed to finding one representative normal value for these parameters, a range of normal values was defined. For instance, the average trunk mass was 42.2% +/- 3.5% (x +/- SD) of body mass, but values ranged from 35.8% to 48.0%. To account for segment parameters more accurately, specific anthropometric measures need to be considered in addition to overall measures of body height and mass. These specific measures included segment length, circumference, width, and depth. Studies reporting general percentages based on height and/or mass were found to be inadequate predictors of segmental parameters of the trunk compared with MRI estimates. Volume-based estimates, which assume a uniform density distribution within a segment, were found to correspond closely to MRI values except for the thorax. However, the use of density values reflective of the living in vivo state would likely alleviate this disparity, thus indicating that the volumetric technique may be effective for deriving segmental parameters for large segments of the trunk. Future research should adopt noninvasive techniques such as MRI and/or volumetric estimation to enhance the predictability of segmental parameters of the body for specific population groups characterized by gender, developmental age, body type, and fitness level. Further efforts should be made to establish standardized boundary definitions for trunk segments to avoid unnecessary confusion, from which substantial errors may be introduced into biomechanical linked-segment analyses of human movement.

The purpose of this study was to develop a reliable and specific polymerase chain reaction (PCR) for the detection of hepatitis C virus-ribonucleic acid (HCV-RNA) in the plasma of blood donors who attend the Yorkshire Regional Transfusion Centre. These donors had previously had a positive or indeterminate recombinant immunoblot assay (RIBA) result. For increased sensitivity of reaction and greater specificity of product, a 'nested-primer' PCR was used. One hundred and ninety-two samples were examined, of which 18 were RIBA-positive and HCV-RNA was detected in 15 (83%) of them. Of the 174 RIBA indeterminates only one (0.6%) had detectable HCV-RNA. The rate of HCV-RNA detection in fresh and archive samples was compared and found to be greater with the fresh samples.

The history of the techniques used to assess body segment parameters for biomechanical analysis has been reviewed. Three time periods of research were defined, based on the predominant instrumentation used, leading up to the modern era of computed tomography and magnetic resonance imagery. Organised in this manner, the significant techniques and findings were discussed. Current databases are deficient in several aspects: the small number of study participants used for development of standards, the potential inaccuracy of cadaver data compared with that of living humans, and the relative lack of study of diverse populations. Future efforts should be directed towards addressing these weaknesses in body segment parameter information, in order to improve biomechanical investigation in the clinica, ergonomic and sport environments.

Magnetic resonance images from fifteen physically active and asymptomatic male volunteers were collected to present morphometric parameters on the psoas and its moment arms, which are important in the study of spinal mechanics and models for the investigation of low back pain. The mean age of the subjects was 21.5 +/- 1.8 years. Data were obtained from nine vertebral and/or intervertebral levels (L2, L2/L3, L3, L3/L4, L4, L4/L5, L5, L5/S1, S1). In general, the psoas increased in size as it descended the trunk, moving anteriorly and slightly laterally in relation to the vertebral column. Maximum cross-sectional areas for the psoas (M = 16.3cm2) were observed at the L4/L5 level. Right-left symmetry was apparent in the aforementioned dimension, but not with respect to the mediolateral (X) diameter of the muscle. The length of the X moment arm was significantly (p < .05) greater for the right versus the left psoas from L3 to S1, with the length increasing as the psoas descended the trunk. However, this trend was not noted for the anteroposterior (Y) moment arm where observed values remained relatively small throughout the course of the muscle. These results will contribute to the study of low back pain onset and the design of appropriate rehabilitation interventions by providing accurate morphometric parameters for biomechanical models to predict of the loading conditions of the spine in vivo.

The premise behind most noninvasive techniques for the measurement of scoliotic conditions of the spine is that the lateral distortion of the spine relates directly to transverse rib cage deformity within the transverse plane. The focus of this study was to examine this assumption by comparing different noninvasive methods for the assessment of scoliotic curves. The three techniques examined were (1) use of the Scoliometer (SCOL), (2) use of the back-contour device (BCD), and (3) use of moiré topographic imaging (MTI). Fourteen subjects (10 female, 4 male) with idiopathic adolescent scoliosis were measured. Posterior-anterior radiographs were obtained for the clinical assessment of all subjects and were subsequently used to determine Cobb angles. Significant correlations between axial trunk rotation and Cobb-angle measurements were observed in the thoracic region (MTI, r = .80, df = 10, P less than .005; BCD, r = .70, df = 10, P less than .025; SCOL, r = .59, df = 10, P less than .025) but were not found within the lumbar region (MTI, r = .42; BCD, r = .17; SCOL, r = .20). Factors other than trunk deformity, such as the posture assumed by the subject during measurement, may have influenced axial trunk rotation. Hence, the techniques appear to provide valid estimations of lateral curvature of the spine in the thoracic region of the trunk but not the lumbar region. The results suggest that the measurement techniques cannot be used interchangeably in clinical recording.

The purpose of this study was to investigate the sagittal thoracolumbar spine posture as represented by the vertebral centroids and to identify their relative position to the whole body's line of gravity. A non-invasive method was used to calculate the thoracolumbar centroid curve within the sagittal plane from back skin profiles. Twenty-eight male and fifteen female adolescents, of 14 and 15 years of age, were evaluated. The vertebral centroid postures were varied but the females' curve was found to be significantly more posterior of the line of gravity than the males' curve (P < 0.05). Also, the degree of kyphotic curvature was significantly greater in the males than the females (P < 0.05). The posture assumed by the spine, as indicated by the kyphotic and lordotic curvatures, was found to have a significant correlation (r(2) from 0.71 and 0.51 respectively) with the cumulative centroid displacement of the line of gravity and with gender, as well as with height, mass and spine depth., (Copyright © 1992. Published by Elsevier Ltd.)

The present study examined the relative accuracy and precision of MR and CT procedures for determining the CSA of individual muscles from the human thigh. Serial AN, CT and MR cross-sections were obtained from three cadaveric lower limbs. The MR measurements provided accurate and precise values for the CSAs of most thigh muscles, generally within +/- 7.5% of the AN standard. In contrast, CT tended systematically to overestimate the AN CSA by 10-20%. Retest procedures indicated that highly reliable measurements could be obtained from both MR and CT images. However, subjective interpretations of boundaries between closely apposed muscle bellies, particularly for muscles with more than one head, were necessary for resolving entities in the imaging records and this decreased the relative accuracy of MR and CT measures. Interestingly, MR records demonstrated an incomplete septum between vastus lateralis and vastus intermedius more prominently than AN cross-sections. The novel cross-validation procedures used in this study also highlighted several system-based errors in the MR records that, if undetected and left uncorrected, would have seriously biased the morphometric data obtained with this technique. In general, MR provides high resolution images of the human thigh muscles which may be used to obtain valid measures of the CSA of these structures.

The lumbar compressive and shear forces were determined using a computer model, BIOMECH6, during the performance of the longlaying, hooklaying and bench curl-ups. The lumbar spine curvature and iliopsoas tension were determined for each position and supplied to BIOMECH6 to determine these forces. The lumbar forces were maximized during the initial position of the longlaying curl-up. During the initial position of the hooklaying curl-up, the compressive forces were only reduced by 5% (male) and 4% (female) while the shear forces were reduced by 46% (male) and 39% (female) The bench curl-up minimized these forces; the compressive forces were reduced by 17% (male) and 18% (female) while the shear forces were reduced by 87% (male) and 97% (female). The lumbar forces were reduced for the 45° curl-up position in all three variations when compared to the initial position, except for the bench curl-up where the shear forces increased slightly. These results indicated that to minimize the lumbar spine forces, the bench curl-up was the most beneficial method., (Copyright © 1991. Published by Elsevier Ltd.)

This longitudinal study examined the postural changes that occur during pregnancy and their association with low-back pain. The lordotic curvature, kyphotic curvature and position of the line of gravity were measured. The degree of low-back pain was assessed using a daily pain diary. Each measurement was recorded in 30 healthy pregnant women on a monthly basis until term and once post partum. The results reveal many different postural behaviours, but the majority of women experienced a flattening of the lumbar spine during pregnancy. The changes in kyphotic curvature were not so well defined. In the majority of women the position of the line of gravity was unaffected during pregnancy. Most women experienced some degree of low-back pain but in most cases it was mild. Although Pearson product-moment correlations revealed few significant correlations, the most interesting finding was that in the early stages of pregnancy, the changes in lordosis and lowback pain were inversely related., (Copyright © 1990. Published by Elsevier Ltd.)

The purpose of this study was to make a kinetic comparison of backward and forward giant swings on the horizontal bar. Six Canadian gymnasts of national calibre were filmed using a high speed camera during the performance of giant swings on a horizontal bar which was equipped with strain and torque gauges. Prior to filming, the horizontal bar was calibrated by force application at various angles. During the performances, voltage outputs representing force and torque were amplified and recorded on tape. The force/torque data were then subjected to computer analysis. Forces were plotted circularly against the angle at which the forces acted on the bar using an x-y plotter. Maximum forces and torques for both forward and backward giant swings were compared. Polar force plots were then normalized by dividing force by body weight. A superposition of curves for 11 backward giant swings and 12 forward giant swings has produced two models representing good performance of giant swings by national gymnasts. Deviations from the models may be useful in correction of errors in execution of the swings. This method could provide instantaneous feedback on performance technique without requiring film analysis.

Following surgery and regional radiotherapy for operable carcinoma of the breast in premenopausal women, ovarian irradiation (2000 rad in five daily fractions) plus prednisone (7.5 mg per day) results in delayed recurrence and prolonged survival.

The menisci of the knee are important structures for maintaining a healthy joint since they absorb shock and prevent rotatory instability. The shapes of the menisci and the orientations of their collagen fibres are naturally suited for bearing weight of the joint. Their shape also allows the tibial plateau contact area to be three times greater, thereby decreasing the stress by up to seven times. The medial and lateral menisci are able to move to different extents as a result of the variable laxities of the adjoining ligaments. Often a meniscus becomes injured and must be surgically removed by either a partial or total meniscectomy. Many meniscal injuries occur during sports activities and are caused predominantly by a twisting motion. A meniscectomy has been shown to have detrimental effects including increased joint laxity, osteoarthritis, and other structural changes. Approximately 25% of those who have had a total meniscectomy must stop or restrict their sports activities.

The purpose of this study was to determine the center of mass of the trunk in living subjects by using computed tomography (CT), thus providing more accurate data to aid scientists in their effort to describe human motion quantitatively. This advanced x-ray was used to analyze the trunk segment of four subjects, two men and two women, ranging in age from 46 to 68 years. Scans were taken at 1 cm intervals, from the level of the superior surface of the pubic symphysis to the suprasternal notch. Data were processed by an on-line computer, with the object represented on photographic film as a gradient image of gray levels. The intensity of the gray scale in each cross-sectional scan corresponded to a particular density of human body tissue. The computer program was capable of interpreting this information, thereby providing values for the center of mass, tissue density, segmental mass, and volume. The study's conclusions are based on data obtained from living subjects which may be representative of the general adult population. We found that the mean center of mass of the trunk segment was 49.35% of the total length as measured from the line joining the greater trochanters across the superior surface of the pubic symphysis to the suprasternal notch. Furthermore, the segmental mass of the trunk segment was found to be 52.58% of total body weight. These data differ from trunk cadaveric studies already published.

The purpose of this study was to investigate the roles of specific muscles in supporting the elbow joint in full extension during a static weighted situation. Various forearm positions from pronation through supination were used to determine carrying efficiency by monitoring muscle activity. Fine-wire electrodes were inserted into the biceps brachii, brachialis, brachioradialis, and medial head of the triceps in order to record the action potentials of these muscles. The forearm was studied in four different positions: (1) prone, (2) relaxed or natural, (3) semiprone, and (4) supine. These positions were monitored by an elgon potentiometer. The loads for the subjects were from 2-20 kilograms. Reliability coefficients of repeated trials were significantly positive. It was concluded that the muscles played an important role in supporting the elbow in full extension during a detracting force and that there was no significant difference between the muscular activity of males and females. Of the four positions studied, the supine position required the most activity suggesting an inefficient carrying position. The triceps was significantly more active when the arm was in the prone position. The roles of muscle groups in supporting the fully extended elbow joint during a detracting force changed as the forearm moved between supination and pronation. The elbow flexors were most active in the supine position, while the elbow extensor muscle was most active in the prone position.

Evidence is presented from a study of 680 patients followed over a period of 21 years that conservative treatment of breast cancer by local excision of the primary tumor followed by breast irradiation yields results equivalent to the traditional radical approach, with the added benefit of an excellent cosmetic result and improved quality of life. The relative survivals were 8.3% at 5 years and 71% at 10 years. There was no difference in survival when radiation was given. Breast irradiation significantly reduced relapse in the breast, but axillary irradiation did not influence relapse at this site. Relapse in the breast alone was not detrimental to survival if treated appropriately. Axillary relapse indicated a much poorer prognosis as might be expected.

A prospective, stratified, randomized study of 190 postoperative ovarian patients with Stages IB, II, and III (asymptomatic) presentations is reported. The median time of follow-up was 52 months. Patients in whom bilateral salpingo-oophorectomy and hysterectomy (BSOH) could not be completed because of extensive pelvic tumor had a poor prognosis which did not differ for any of the therapied tested. When BSOH was completed, pelvic plus abdominopelvic irradiation (P + AB) with no diaphragmatic shielding significnatly improved patient survival rate and long-term control of occult upper abdominal disease in approximately 25% more patients than pelvic irradiation alone or followed by adjuvant daily chlorambucil therapy. The effectiveness of P + AB in BSOH-completed patients was independent of stage or tumor grade and was most clearly appreciated in patients with all gross tumor removed. Chlorambucil added to pelvic irradiation delayed the time to treatment failure without reducing the number of treatment failures.

The effectiveness of contingent restraint in reducing stereotyped body rocking of profoundly retarded subjects was investigated to determine (a) whether restraint reduced stereotyped body rocking and (b) the degree to which the effectiveness of restraint depended upon where in the behavioral sequence it was administered. Results showed that restraint, in comparison to no restraint, reduced the amount of body rocking. Also, restraint was judged to be generally more effective if it were applied when the subject was bent over in the middle of the response sequence rather than administered while the subject was sitting upright at the end of the response sequence. The results were interpreted in terms of response chaining and postural feedback. Implications for the utilization of physical restraint as a behavioral intervention were discussed.

The purpose of this study was to determine the forces and torques on the horizontal bar during the kip. Six Canadian male gymnasts were filmed using a high speed camera during a short gymnastic routine including a kip on a horizontal bar which was wired with strain and torque gauges. During the performance, voltage outputs representing force and torque were amplified and recorded on tape. The force-torque data were then subjected to computer analysis. Maximum forces and torques were determined and force-angle plots were normalized by dividing force by body weight. The range of maximum forces was 1344-1563 N with a mean of 1444 N, which was approximately 2.3 times the body weight. The maximum forces were obtained when the center of mass was almost directly below the bar with the timing of maximum force application ranging +/- 0.1 sec from either side of 180 degrees. Maximum torques ranged from 10.0-21.0 N X m (Mean 17.3 N X m).

An investigation of the absolute strength of the human muscle was carried out on the in vivo erector spinae muscle using magnetic resonance tomography coupled with dynamic muscular testing. The absolute strength of the erector spinae was calculated to be 48 N/cm2. The area of the rectus abdominis was 15.1 cm2, and the area of the erector spinae was 54.5 cm2. The internal moment arm for the rectus abdominis and erector spinae muscles was 7.04 and 5.64 cm, respectively. The static force measures showed the trunk extensor moment to be only 30% greater than the flexor moment. The difference is discussed in terms of the absolute strength of muscle, and other anatomic factors.

Mathematical modeling of human joints requires accurate information concerning anthropometric parameters such as muscle cross-sectional areas and muscle moment arms. The purpose of this study was to calculate the average crosssectional area, average volume, and length of the muscle moment arms about the spinal column for the rectus abdominis (RA) and the erector spinae (ES) for those portions of the muscles that are involved in spinal flexion and extension. Materials for this study came from archival computed tomography scans of 28 living subjects. The muscle outlines were digitized and the moment arms calculated as a percentage of anteroposterior trunk depth. The average cross-sectional area of the RA was 10.5 cm2, and 31.75 cm2 for the ES. The average volumes for the RA and ES were 356.16 cm3 and 843.46 cm3, respectively. The muscle moment arm ratio was 0.29 for the ES, while the males and females had ratios of 0.50 and 0.40, respectively, for the RA. Computed tomography scanning is a method that allows the accurate calculation of internal anthropometric parameters that will be of use in mathematical modeling. J Orthop Sports Phys Ther 1985;6(5):278-280.

Patch tests in 1000 cases of contact allergic dermatitis observed between 1972 and 1978 are recorded in detail, and compared in general with patch tests in a previously recorded 1000 cases of contact allergic dermatitis between 1964 adn 1972. The routine use, since 1974, of patch tests as advised by the International Contact Dermatitis Research Group has increased the detection of dermatitis caused by nickel, paraphenylene-diamine and related dyes, formaldehyde and perfumes (balsam of Peru), which indicates that aimed patch tests alone may be inadequate. The number of cases of dermatitis caused by antifungal agents and topical antihistamines decreased after Commonwealth and State legislation prohibiting their use was passed.

Following mastectomy, patients with operable breast cancer underwent postoperative irradiation of the chest wall and regional lymph nodes. They were then assigned at random to receive no further therapy, ovarian irradiation (2000 rads in 5 days) or ovarian irradiation in the same dosage plus prednisone, 7.5 mg daily. A total of 705 patients received the randomly assigned treatment and were followed for up to 10 years. In premenopausal patients who received ovarian irradiation the recurrence of breast cancer was delayed and survival prolonged, but not significantly. In premenopausal women aged 45 years or more ovarian irradiation plus prednisone therapy significantly delayed the recurrence of breast cancer (P = 0.02) and prolonged survival (P = 0.02); the survival expectancy of these patients was similar to that of the general population of the same age from the third year after the cancer operation. No value was demonstrated for ovarian irradiation with or without prednisone therapy in postmenopausal patients.