摘要:

A predictive risk model of low-back pain (LBP) disability was developed by a panel of six experts in the fields of chronic pain and disability. It comprised 28 factors organized into eight categories: job, psychosocial, injury, diagnostic, demographic, medical history, health behaviors, and anthropometric characteristics and was administered as a 15-minute written questionnaire. The model was tested prospectively on 250 patients (age range, 18–65 years) attending two secondary-care low-back clinics. Disability, as predicted by the model, was compared with 1) actual disability assessed 3 and 6 months later; 2) predictions of disability made by the attending physicians; and 3) predictions obtained from an empirically derived model. These results showed that 1) the expert-generated risk model had a predictive accuracy of 89% and did better in predicting disability than the physicians across all samples and 2) the empirically weighted model did best of all (91% predictive accuracy), suggesting that the expert model used appropriate factors but that the weights assigned to these factors by the panel of experts could be improved.

ISSN:0362-2436    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

Several factors were studied for their association with the prevalence of chronic low-back syndromes, sciatica, and unspecified low-back pain (LBP) in 2,946 women and 2,727 men (age range, 30–64 years) participating in the Mini-Finland Health Survey, a project aimed at comprehensive evaluation of the population's health. On the basis of a standardized clinical examination, a physician diagnosed sciatica in 5.1% and LBP in 11.6% of the subjects. Those with a previous traumatic back injury had 2.5-fold risk of having sciatica or LBP. The fractions of sciatica and LBP attributable to such back injuries were estimated to be 16.5% and 13.7%, respectively. Sum indices of both physical and mental stress at work were found to be directly proportional to the prevalence of sciatica and LBP. Smokers had an increased risk of LBP, and body height was related positively to the prevalence of sciatica. These associations, however, were inconsistent between sex and age subgroups. In the presence of osteoarthritis in the knee, hip, or hand, LBP was prevalent (adjusted odds ratio [OR], 5.3; 95% confidence interval [CI], 4.1–6.9), but sciatica was not (OR, 1.1; 95% CI, 0.7–1.7). Diabetics were found to have a significantly decreased prevalence of LBP (OR, 0.4; 95% CI, 0.3–0.8). Many factors, independent of each other, determine the occurrence of chronic low-back syndromes. The determinants of sciatica and LBP are different of some extent.

ISSN:0362-2436    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

The clinical course of 19 untreated patients with spinal stenosis (mean age, 60 years) was compared with that of 44 patients treated surgically (mean age, 65 years). The time of follow-up was 31 and 53 months, respectively. About 80% of the patients had neurogenic intermittent claudication. In the follow-up, one third of the treated and one half of the untreated patients still had neurogenic claudication. By visual analogue-scale estimation, 60% of those treated surgically and 33% of the untreated patients felt better. Fifty-eight percent of the untreated patients were unchanged. Neurophysiologic changes showed progression in almost all cases; it was more pronounced in the treated patients. No proof of severe deterioration was found in the untreated patients, and observation for 2–3 years seems to be a good alternative to surgery.

ISSN:0362-2436    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

In a prospective single-blind study, 60 patients surgically treated for lumbar disc herniation underwent clinical examination and computed tomography preoperatively and 3 months after surgery.At follow-up (58 patients; median, 31 months; range, 21–37 months), 29 patients had an excellent outcome (51%), 20 improved (33%), and 9 were unchanged or worse (16%).Dural or radicular scar tissue was present by computed tomography in 88% of the patients, but the findings could not be correlated with the clinical outcome. Recurrent or persistent disc hemiation was found in 9% of the patients. The clinical outcome of patients with abnormal computed tomography did not differ significantly from patients without this finding. A relation between facet joint degeneration and less successful clinical outcome was demonstrated. Computed tomography (without contrast) 3 months after surgery gave little information which could be correlated with the clinical outcome. Patients with an excellent outcome had all degree of intraspinal scar tissue.

ISSN:0362-2436    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

The role of thermography for diagnosing lumbar radiculopathy was evaluated by literature review and meta-analysis. From 81 relevant citations, 28 studies could be analyzed for diagnostic-accuracy data (sensitivity and specificity) and method. Diagnostic-accuracy data varied significantly between studies; therefore meaningful pooled summary statistics could not be reported. Twenty-seven studies had major methodologic flaws including biased test interpretations, faulty cohort assembly, poor clinical descriptions, and small sample size. The only study of reasonably high quality found no discriminant value for liquid-crystal thermography. The role of thermography remains unclear. Rigorous clinical research is required to establish its diagnostic accuracy and clinical utility. Thermography cannot be recommended currently for routine clinical use in evaluating low-back pain.

ISSN:0362-2436    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

Magnetic resonance imaging (MRI) findings of 89 autopsied intervertebral discs from 22 cadaveric lumbar spines were correlated with biochemical composition, conventional radiography, and histologic structure to study the nature of disc intensity changes seen in MRI. Discs with a low signal intensity on T2-weighted MRI were characterized by shortening of relaxation times, dehydration, and decreases in total proteoglycan content and chondroitin-keratan sulfate ratios in the nucleus pulposus. This corresponded well with previously published studies. In histologic structure, no obvious differences between MRI findings were found. In conclusion, a low signal intensity in a lumbar disc on T2-weighted MRI probably reflects a true biochemical disc degeneration, but its relation to structural degenerative changes is uncertain. Therefore, MRI seems to be a sensitive and a specific imaging modality for detecting pathologic biochemical disc changes in the spine of a young adult.

ISSN:0362-2436    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

Thein vivoandex vivomicroanatomic appearance of early disc degeneration were identified by magnetic resonance imaging and correlated with their respective histoipathologic findings. Five cadaver spines (18 discs) and 25 patient studies (122 discs) all imaged at 1.5 Tesla were studied. Two signs of early degenerative disc disease were found: infolding and the central dot. Infolding of the central fibers of the outer annulus coalesced into a central dot of low signal intensity that was seen on both theex vivoandin vivoimages. Infolding was seen 29 of 122 times, and the central dot was observed 15 of 122 times on thein vivoimages. A later form of degenerative disc disease was identified as a separation of the nucleus pulposus from the hyaline cartilage end-plate. This separation was seen as a linear area of either low or high signal intensity on theex vivoimages but only as a band of high signal intensity on thein vivospin-echo 2,500-msec/80-msec images. Only 7 of 122in vivodiscs showed this separation. Internal herniation of nucleus pulposus into the outer annulus was seen only on theex vivoimages. Early degenerative disc disease may exist before there is loss of disc height or signal intensity on the long time-to-repetition (TR)/time-to-echo (TE) magnetic resonance images.

ISSN:0362-2436    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

Partial discectomy was donein vitroon 15 human lumbar discs from donors 20–40 years of age. The change of disc height, radial disc bulge, and intradiscal pressure was measured in relation to the mass of central disc tissue excised. Disc height decreases and radial disc bulge increases approximately in proportion with the mass of the tissue excised. At the same time, intradiscal pressure decreases. On average, removal of 1 g of disc tissue results in a height decrease of 0.8 mm and a radial bulge increase of 0.2 mm. Removal of 3 g of central disc tissue lowers the intradiscal pressure to approximately 40% of its initial value. A mechanical model is presented which explains the observed relation between the volume of material removed and the subsequent change of height, bulge, and pressure. The experimental results and the model provide insight into the rationale of disc pressurization. A high intradiscal pressure is a prerequisite for the mechanical function of the disc under physiologic conditions.

ISSN:0362-2436    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

The effect of equivalent mineral density on pedicular screw fixation strength was investigated. The equivalent mineral density of human vertebral bodies was correlated highly with the pullout force of Kluger screws (r2= 0.61,P< 0.02). A moderate to high correlation existed between density and vertical force (r2= 0.42 for Kluger screws,r2= 0.55 for Steffee screws,P< 0.02). In calf vertebral bodies of higher density (146 ± 14 mg/cc), the forces were significantly higher than in the human vertebral bodies (P< 0.05). Human lumbosacral spines were instrumented with three different fixators: Steffee plates, AO fixateur interne, and Kluger fixateur interne. Of five specimens with a mean density of 88 ± 11 mg/cc, one, screw loosened. More than one screw loosened in six specimens with a mean density of 63 ± 12 mg/cc, and no screw loosened in four specimens with a mean density of 114 ± 38 mg/cc. Measurement of equivalent mineral density correlates with the fixation strength of the intrapedicular screws.in vitroand should be considered in patients with signs of osteopenia before using pedicular screws for spinal fusions. It is also concluded that calf spines are a good model for testing implants because they tend to focus failure processes in the implant rather than in the implant-bone interface.

ISSN:0362-2436    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

Although it is accepted that the intervertebral disc has a sensory component, it has not been previously shown by any specific method. Immunoreactivity of the physiologically active neuropeptide, calcitonin gene-related peptide (CGRP), was used as a specific marker of sensory nerve fibers and their endings in the intervertebral disc of the rat. In this study, positive fiber immunoreactivity was taken as an indication that those fibers were of sensory, and not sympathetic, origin. Immunoreactivity was found in the outer annulus fibrosus of all intervertebral discs studied. The CGRP-like immunoreactivity was also found in structures that resembled nerve endings. To the authors' knowledge, this is the first report presenting detailed positive evidence of sensory fibers and their endings in the lumbar intervertebral disc of any mammalian species.

ISSN:0362-2436    

出版商:OVID    

年代:1991

数据来源: OVID