摘要:

The primary objective of this study was to determine whether disc degeneration, as assessed through magnetic resonance imaging, is greater in smokers than in nonsmokers. To control for the maximum number of potentially confounding variables, pairs of identical twins highly discordant for cigarette smoking were selected as study subjects. Data analyses revealed 18% greater mean disc degeneration scores in the lumbar spines of smokers as compared with nonsmokers. The effect was present across the entire lumbar spine, implicating a mechanism acting systemically. This investigation demonstrates the efficiency of using carefully selected controls in studying conditions of multifactorial etiology, such as disc degeneration.

ISSN:0362-2436    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

An animal model of cauda equina syndrome was developed. Neurologic recovery was analyzed following immediate, early, and delayed decompression. Five experimental groups, each containing six dogs, were studied. Compression of the cauda equina was performed in all 30 dogs following an L6-7 laminectomy. The cauda equina was constricted by 75% in each group. The first group was constricted and immediately decompressed. The remaining groups were constricted for 1 hour, 6 hours, 24 hours, and 1 week, respectively, before being decompressed. Somatosensory evoked potentials were performed before and after surgery, before and immediately after decompression, and 6 weeks following decompression. Daily neurologic exams using the Tarlov grading scale were performed. At 6 weeks postdecompression, all dogs were killed, and the neural elements analyzed histologically. Following compression, all 30 dogs had significant lower extremity weakness, tail paralysis, and urinary incontinence. All dogs recovered significant motor function 6 weeks following decompression. The dogs with immediate decompression generally recovered neurologic function within 2-5 days. The dogs receiving 1-hour and 6-hour compression recovered within 5-7 days. The dogs receiving 24-hour compression remained paraparetic 5-7 days, with bladder dysfunction for 7-10 days and tail dysfunction persisting for 4 weeks. The dogs with compression for 1 week were paraparetic (Tarlov Grade 2 or 3) and incontinent during the duration of cauda equina compression. They recovered to walking by 1 week and Tarlov Grade 5 with bladder and tail control at the time of euthanasia. Immediately after compression, all five groups demonstrated at least 50% deterioration of the posterior tibial nerve evoked potential amplitudes. Six weeks after decompression, all five groups had a mean amplitude recovery of 20-30%. There were no statistical differences in recovery of somatosensory evoked potentials among the groups. Histologic analysis of the cauda equina in all groups demonstrated scattered wallerian degeneration and axonal regeneration. Areas of poor myelination, fibrosis, and macrophage activity were seen at the level of constriction. There were no significant differences in the histologic neuroanatomy of the five groups. It has been advocated that early decompression of cauda equina syndrome enhances neurologic recovery. This study does not support this premise. Although decompression allowed significant recovery in all 30 dogs, no significant differences were found in somatosensory evoked potentials, neurologic recovery, or histopathology in groups decompressed immediately, at 1 hour, 6 hours, 24 hours, or 1 week.

ISSN:0362-2436    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

Several types of collagen are known to exist in the intervertebral disc in addition to the fibrillar collagens, Types I and II. Although they constitute only a small percentage of the total collagen content, these minor collagens may have important functions. This study was designed to investigate the presence of Types I, II, III, IV, VI, and IX collagens in the intervertebral disc and cartilage end plate by immunohistochemistry, thereby establishing their location within the tissues. Types III and VI collagen have a pericellular distribution in animal and human tissue. No staining for Type IX collagen was present in normal human disc, but in rat and bovine intervertebral disc, it was also located pericellularly. These results show that cells of the intervertebral disc and cartilage end plate sit in fibrous capsules, forming chondrons similar to those described in articular cartilage. In pathologic tissue the amount and distribution of the collagen types, and the organization of the pericellular capsule, differ from that seen in control material.

ISSN:0362-2436    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

A prospective, blinded cohort study was performed to investigate the relationship between biomechanical variables measured during lumbar dynamometry and several psychological tests and measures of nonorganic pain behavior. Eighty-five men, aged 18-60 years, who had had low-back pain for longer than 5 weeks participated in the study. Nonorganic pain behavior was measured with the Waddell score, and lumbar function was measured with the Isostation B-200 Lumbar Dynamometer. Two brief psychological tests, the Coopersmith Self-Esteem Inventory and an analog self-rating of wellness, were also administered. Relationships between biomechanical variables and psychological tests were calculated with thet-test, the Pearsonrcorrelation, analysis of variance, and multiple step-wise logistic regression. Patients who exhibited excessive illness behavior (Waddell Scores 3-5) performed significantly worse (P< .01) on almost all biomechanical variables. The Coopersmith Self-Esteem Score and “feelings” score had a slightly weaker but still significant correlation with motor performance. The results suggest that poor performance on biomechanical testing in this population may be a form of abnormal illness behavior and thus may not accurately reflect organic alterations of neuromusculoskeletal function.

ISSN:0362-2436    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

Clinical features, contrast-enhanced lumbar tomographic findings, and biochemical plasma fibrinolytic parameters were critically assessed in 70 patients suffering severe, chronic postsurgical low-back and radicular pain to determine the cause of their persisting symptoms. Patients exhibited gross functional disability and significant impairment of plasma fibrinolytic activity, compared with 84 normal control subjects. This fibrinolytic defect appeared attributable to disproportionate increases in circulating plasminogen activator inhibitor-1 levels. Clinical features were slightly worse in patients with radiologic epidural fibrosis, whereas the frequency of radiologic abnormalities, including epidural fibrosis, was higher in patients with fibrinolytic abnormalities. The results, however, demonstrated no significant associations between patients' symptoms and signs and their biochemical and radiologic abnormalities.

ISSN:0362-2436    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

The erythrocyte sedimentation rate and total white cell count were measured in 110 patients who underwent lumbar spine surgery. Measurements were made before surgery; at 2 and 4 days; and at 1,2,6, and 16 weeks after surgery. A rapid increase of erythrocyte sedimentation rate was seen with peak value on the fourth postoperative day. After 2 weeks, the values were normalized for the majority of patients. Maximum mean peak value was seen 4 days after surgery for fusion (ESR= 102), which was higher than after disc surgery (ESR = 75). There was no corresponding change in total white cell count. No deep infection was noted in the study group. The erythrocyte sedimentation rate values and total white blood cell count at the time of diagnosis for five patients with postoperative deep infection were used for comparison. At the time of diagnosis, all patients with deep infection had an erythrocyte sedimentation rate value exceeding the corresponding mean value (+ 2 SD). Total white cell count was slightly elevated in one of the five infected patients; the remaining four had a normal count. Erythrocyte sedimentation rate determination shows a homogenous pattern with rapid increase and decline after lumbar spinal surgery in patients without postoperative infection, and patients with postoperative deep infection at the time of diagnosis show erythrocyte sedimentation rate elevation to a degree that usually makes the result diagnostic.

ISSN:0362-2436    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

This study selected 205 subjects aged 55 years who had shoulder and/or back pain complaints to determine the relationship of somatic and nonsomatic pain experience to body build, physical fitness, bone mineral content, serum levels of gamma-glutamyltransferase, occupational workload and intelligence test, educational level, life success, social support, stress at work, monotonous work, and job decision latitude. Men with a somatic back pain drawing experienced more stress at work and had higher serum levels of gamma-glutamyltransferase, indicating a higher intake of alcohol and/or painkillers, but were more satisfied with their jobs compared with men who had a nonsomatic pain drawing. Women with obvious shoulder signs and symptoms and/or a somatic back pain drawing tended heavier than women without symptoms, had higher serum levels of gamma-glutamyltransferase, and found their jobs more mentally demanding than did women with shoulder and/or back pain experience but without obvious shoulder signs and symptoms and/or a nonsomatic back pain drawing.

ISSN:0362-2436    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

The predictive value of psychosocial factors in the development of neck—shoulder and low-back symptoms was investigated in a life-long follow-up study of 154 subjects. Measurements taken in adolescence, such as intelligence, alexithymia (low verbal productivity in projective personality tests), social confidence, hobbies, and the socioeconomic status of the family, showed no consistent associations with neck—shoulder or low-back symptoms in adulthood. Of the variables recorded in adulthood, weak mental resources for promoting health (poor sense of coherence) were consistently associated with neck—shoulder pain, whereas low fundamental education predicted low-back symptoms. The results suggest that psychosocial factors in childhood have a minor role as direct predictors of later symptoms.

ISSN:0362-2436    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

Many of the individual biological, psychological, and social factors attributed to low-back disability have been tested previously for their ability to predict treatment outcomes. To test the assumption that disability exaggeration affects treatment outcomes, models were developed to quantify this complex characteristic and to test its predictive value. Two hundred fifty-eight patients with chronic back disability entering a program of functional restoration were initially evaluated with a battery of tests, including measurements of trunk flexibility, lifting capacity, cycling endurance, self-assessments of pain and disability, and psychological attributes. On the basis of these measurements, patients were characterized as disability exaggerators if by peer comparison their self-assessments of pain and disability were in the most severe range despite high levels of physical capacity. Program completion and work status 1 and 2 years after treatment were compared between disability exaggerators and their peers. Individual initial attributes associated with program completion included pain intensity and Million Visual Analogue scores, lifting capacity, trunk flexibility, some Minnesota Multiphasic Personality Inventory and Million Behavioral Health Inventory scales, and cigarette smoking. One-year re-employment was associated with Minnesota Multiphasic Personality Inventory Scale 8, Wechsler Adult Intelligence Score-Revised, and cycling endurance. There were no significant associations between any individual factor and 2-year work status. Only two of the 12 disability exaggeration models distinguished between program graduates and dropouts, and none of the models accurately predicted return to work following treatment. Prescription of intensive multidisciplinary treatment should not be denied on the basis of any individual patient attribute or of disability exaggeration, as measured in this study. Measurement of disability exaggeration may be improved by the use of taskspecific comparisons of self-perceived and observed physical capacities. Disability exaggeration may be more useful in predicting outcomes of treatments that neglect its psychosocial components.

ISSN:0362-2436    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

A comparative evaluation of eight psychometric instruments was made in 274 patients who were currently suffering or previously had suffered from low-back pain. The specificity and sensitivity values for detection of psychological disturbance were calculated and optimum cutoff scores determined for each test. The influence of current pain, social group, compensation, migrant status, and unemployment on the accuracy of each test were evaluated. The Pain Drawing, the Inappropriate Symptoms, the Inappropriate Signs, and the Illness Behavior Questionnaire were found to be least discriminating. The Modified Somatic Perception Questionnaire, the Hospital Anxiety Scale, the Hospital Depression Scale, and the Zung Depression Scale were the most accurate and least affected by the factors examined. The combination of the Modified Somatic Perception Questionnaire and the Zung Depression Scale yielded specificities and sensitivities of 91% and 84% for men and 96% and 85% for women, respectively. This combination is recommended for the assessment of psychological disturbance in patients with low-back pain.

ISSN:0362-2436    

出版商:OVID    

年代:1991

数据来源: OVID