摘要:

It has been proposed that pain treatment evaluation is hindered by heterogencous properties of patient samples. Therefore, to facilitate pain treatment evaluation in this psychological study, a heterogeneous group of chronic low back pain patients was classified into more homogeneous subgroups. Two designs wera used to compare the outcome by the “functioning activation” and the “spa resort” type of rehabilitation. In the first design, the outcome was compared in groups, clinlcally homogenized by sociodemographic variables and in respect to contraindications for heavy physical training. In the second design, the pain patient subgroups, homogenized by cluster analysis technique in accordance with the psychological profiles of functioning, were compared in their response to treatments. The results indicated that the outcome evaluation was facilitated by the letter design releasing more specific information about the effects of the program quality, the patient characteristics, and their interaction on the improvement by rehabilitation. It was concluded that in treatment outcome analysis, the subgroup's homogeneity must be considered.

ISSN:0362-2436    

出版商:OVID    

年代:1992

数据来源: OVID

摘要:

Spinal burst fractures are produced by rapid compressive loading, and may result in spinal cord injury from bone fragments forced from the vertebral body into the spinal canal. This fractura is one of the most difficult injuries of the spine to successfully treat, in part because the biomechanies of reduction and the exact mechanism by which the distraction forces are transmitted to the intracanal fragments of the burst fracture have not been adequately investigated. The authors developed a reproducible technique for creating these fracturesin vitro.The fractures produced were identical to those observed in clinical practice, and were used for investigating the mechanics of this fracture and its reduction. This work describes the pathologic anatomy of the burst fracture both on the gross structure and also on microtome sections of the vertebrae, and examines the biomechanics of fracture reduction. The margins of the vertebral bone fragment, which was forced posteriorly into the spinal canal during fracture, were noted to extend far laterally beyond the pedicles. The authors also found extensive damage not only to the disc above the injured level, but also to that below, explaining the clinical observation that disc degeneration frequently occurs at both levels. Examination of anatomic data provided by microtome section supported the hypothosis that the fibers that actually reduce the intracanal fragment originate in the anulus of the superior vertebra in the midportion of the endplate and insert into the lateral margins of the intracanal fragment. Investigations using magnetic resonance imaging confirmed that these obliquely directed fibers account for the indirect reduction of the fragment. The authors' studies demonstrate that the posterior longitudinal ligament provides only a minor contribution in the reduction of the fracture in comparison to the attachments of the posterior portion of the anulus fibrosus. The forces required to reduce this fragment were studied. Distraction was found to be the predominant force required for indirect posterior reduction. This was confirmed by a series of tests using devices that provided segmental fixation. The application of uniform distraction forces was most effective in the posterior reduction of the intracanal fragment.

ISSN:0362-2436    

出版商:OVID    

年代:1992

数据来源: OVID

摘要:

In a prospective study 122 patients with a slipped lumbar disc and no previous surgery were preoperalively examined for fibrinolytie activity. Surgical results for these patients were evaluated 12 months postoperatively by clinical overall assessment. In a multiple linear regression analysis fibrinolytic variables, euglobulia clot lysis time and plasminogen activator inhibitor 1, were shown to have predictive value regarding outcome of surgery; that is, normal fibrinolytic activity favors a satisfactory outcome and vice versa. Background variables and lipid profile were also recorded preoperatively. Body mass index, P-glutamyl transpeptidase, triglycerides and smoking were of statistical significance in relation to euglobulin clot lysis time and plasminogen activator inhibitor 1. Postoperative fibrinolytic re-examination of 20 patients seem to contirm that patients at risk of surgical failure have a prolonged depression of fibrinolytic activity.

ISSN:0362-2436    

出版商:OVID    

年代:1992

数据来源: OVID

摘要:

An unselected sample of outpatient subjects (n = 330) with localized nonspecific low back pain (LBP) was studied. Investigation consisted of clinical assessment, physical examination, and psychiatric interview based on the DSM-III classification.A psychiatric disorder, according to the DSM-III criteria (axis I) was found in 41% of the subjects. Multiple correspondence analysis and cluster analysis were used to objectively identify clinical subtypes without preconceived theoretical models. Correspondence analyses suggested the existence of a 'psychological pain' syndrome consisting of several of the following symptoms: diffuse back pain, impossibility to assess intensity of pain on a pain seale, aggravation of pain by changing climate, by domestic activities or by psychological factors and dysesthesias in the back. Cluster analysis provided support for a four-group classification of low back pain, which may be interpreted through the relationships between psychological disturbances and the LBP clinical features.The results call for further investigation of the complex relationship between psychological disturbances and back pain. However, clinicians must be aware of the interest of a minimal psychiatric assessment in low back pain patients: psychiatric disorders frequently appear in these patients and an appropriate treatment of the psychiatric syndrome may reduce back pain.

ISSN:0362-2436    

出版商:OVID    

年代:1992

数据来源: OVID

摘要:

A classification study was conducted in an unselected sample of outpatient subjects with localized nonspecific low back pain. The heterogeneity of a subgroup of patientswithouta psychiatric disorder according to the DSM-III classification (axis I), and whose low back pain may be labeled as ‘purely organic’ (see part 1 of the study in the companion paper), led to further evaluation of this group by correspondence and cluster analysis.A seven-cluster population structure emerged from the cluster analysis. Comprehensive description of these clusters suggests at least four well-differentiated clinical entities or ‘syndromes.’ Although no satisfactory correlation with pre-existing ‘pathoanatomic’ classification or hypotheses was found, this variable clinical presentation suggests different etiolgical or physiopathologic patterns for low back pain (and possibly more specific management of this condition). More comprehensive descriptions and evaluations of clinical symptoms and syndromes appear necessary in order to elaborate a clinical classification of LBP.

ISSN:0362-2436    

出版商:OVID    

年代:1992

数据来源: OVID

摘要:

This study was undertaken to follow up an incidence rate study of spinal injuries carried out from a cross-sectional random sample consisting of 2,342 workers who were compensated at least once in the year 1981 by the Cuebec Worker's Compensation Board (QWCB) for an absence from Work. These workers were followed for 3 years using the QWCB information system to record any recurrence of compensated absence from work. A total of 850 (36.3%) had at least one recurrence, and had longer episodes of absence than those without a recurrence (P < 0.0001). Of these 850 workers. 824 (96.9%) had less than five recurrences and showed a systematic trend of gradual increasing duration of absence on each subsequent recurrence (P < 0.05 in a repeated measures analysis of variance). A positive relationship was found between the duration of the initial episode of absence from work and the subsequent history of absence from work, both in terms of risk of recurrence (P < 0.001) and of cumulated absence from work (P < 0.0001), after controlling for age, sex, and site of symptams. The computed instantaneous risk of entering a recurrence in a 31 year-old man experiencing lumbar symptoms, was 19.9% (95% confidence interval = 19.8–19.9) in the year following an initial episode of one day duration, and 26.7% (95% confidence interval = 24.3–29.3) after an initial episode of 6 months.

ISSN:0362-2436    

出版商:OVID    

年代:1992

数据来源: OVID

摘要:

The prevalence of self-reported low back symptoms was investigated by a postal questionnaire in a group of 234 urban bus drivers exposed to whole-body vibration and postural stress and in a control group of 125 maintenance workers employed at the same bus municipal company. The average vertical whole-body vibration magnitude measured on the seat pan of the buses was 0.4 m/s2. After controlling for potential confourders, the prevalence odds ratios for the bus drivers compared to the controls significantly exceeded 1 for several types of low back symptoms (leg pain, acute low back pain, low back pain). The occurrence of low back symptoms increased with increasing whole-body vibration exposure expressed in terms of total (lifetime) vibration dose (years m2/s4), equivalent vibration magnitude (m/s2), and duration of exposure (years of service). The highest prevalence of disc protrusion was found among the bus drivers with more severe whole-body vibration exposure. Frequent awkward postures at work were also related to some types of low back symptoms. It is concluded that bus driving is associated with an increased risk for low back troubles. This excess risk may be due to both whole-body vibration exposure and prolonged sitting in a constrained posture. The findings of this study also indicated that among the bus drivers low back symptoms occurred at whole-body vibration exposure levels that were lower than the health-based exposure limits proposed by the International Standard ISO 2631/1.

ISSN:0362-2436    

出版商:OVID    

年代:1992

数据来源: OVID

摘要:

Most patients with chronic low back pain associate strenuous physical activities with increased pain. This association can cause avoidance of those activities believed to cause intulerable discomfort. This study explored the relationship of parformance of physical activities with self-reported pain measures in 40 consecutive patients with disabling low back pain (mean duration 17 months) during a functional restoration rehabilitation program (mean treatment period 7 weeks). Evaluations were performed at initial presentation and at program completion. Measures included quantification of performance on eight physical tests assessing flexibility, lifting capacity and endurance. Before physical testing patients were asked to complete a pain analog scale, a quantified pain drawing, and a rating of the pain anticipated to result from the performance of each physical test. Results showed that pain measures did not generally correlate with measured physical performance. At completion of treatment, significant improvement in porformance on all physical tests was found, but these were not associated with consistent changes in pain measures. These results demonstrate that subjects with chronic low back pain can increase their physical performance abilities within their same pain experiences. Medical recommendations for subjects' involvement in physical activities should not be based solely on the reported association of pain with those activities.

ISSN:0362-2436    

出版商:OVID    

年代:1992

数据来源: OVID

摘要:

The association between manual materials handling and occupational low back injuries has generated a wide variety of devices and protocols for testing lifting capacity. The validity of these tests depends critically on the subject's effort during the evatuation. This study compares the accuracy of several physiologic effort indices in identifying maximal and submaximal lifting efforts. Twenty-one men and twenty-three women free from back pain underwent isometric, isokinetic, and isoinertial tests of lifting capacity applying 50 and 100% efforts in random order. Effort indices included isokinetic force/distance curve variation, isolnertial puak force: weight ratios and peak force—weight differences, and heart rates and peak force variances for all three modes. Differences between 50 and 100% effort means were significant at P < 0.01 for isokinetic force/distance curve variation, isoinertial peak force: weight ratios, and peak force—weight differences, and for heart rates in all three modes using analysis of variance. Differences were not significant (P > 0.05) for peak force variances in any mode using Wilcoxon Signed Rank Tests. According to a discriminant analysis model with optimal cutoff values, the only effort indices with better than 60% accuracy in identifying maximal and submaximal efforts were isokinetic force/distance curve variation (74%) and isoinertial peak force: weight ratios (69%), peak force—weight differences (62%) and heart rates (65%). For each index, subjects were divided into three groups according to whether their lifting outputs during 50% effort bouts were greater than, equal to, or less than one half their outputs in the 100% effort bouts. For all efforts indices, differences between 50 and 100% efforts were similar in magnitude among these three subject groups, demonstrating that these indices do depend on effort rather than output. The accuracy of previously reported indices of effort is limited and variable. Practitioners using lifting tests in rehabilitation and occupational feasibility evaluations most consider these operational characteristics to avoid inaccurate diagnosis of submaximal test performance.

ISSN:0362-2436    

出版商:OVID    

年代:1992

数据来源: OVID

摘要:

The authors prospectively followed the natural evolution of lumbar disc herniation in 48 patients treated by conservative measures. The initial computed tomographic sean was obtained during the acute phase of the disc herniation and the second was performed 1–48 months after healing. The initial computed tomographic scan allowed classification of the herniations according to size: 13 were considered small, 20 medium and 15 large. Comparison with follow-up computed tomographic scans showed that 9 of the herniations decreased by at least 25%, 8 decreased between 50 and 75% and 31 decreased between 75 and 100%. In the later group, a few had disappeared even though the second computed tomographic scan was performed as early as the month immediately after successful treatment. The largest herniations were those which had the greatest tendency to decrease in size. It is postulated that this could be secondary to the herniation breaking through the outer fibers of the anulus and entering the epidural space.

ISSN:0362-2436    

出版商:OVID    

年代:1992

数据来源: OVID