Association of polymorphism at the type I collagen (COL1A1) locus with reduced bone mineral density, increased fracture risk, and increased collagen turnover.
OBJECTIVE: To examine the relationship between a common polymorphism within intron 1 of the COL1A1 gene and osteoporosis in a nested case-control study. METHODS: We studied 185 healthy women (mean +/- SD age 54.3+/-4.6 years). Bone mineral density (BMD) was measured using dual x-ray absorptiometry, and fractures were determined radiographically. The COL1A1 genotype was assessed using the polymerase chain reaction and Bal I endonuclease digestion. RESULTS: Genotype frequencies were similar to those previously observed and in Hardy-Weinberg equilibrium: SS 61.1%, Ss 36.2%, and ss 2.7%. Carriage of at least one copy of the "s" allele was associated with a significant reduction in lumbar spine BMD (P = 0.02) and an increased risk of total fracture (P = 0.04). Urinary pyridinoline levels were significantly elevated in those with the risk allele (P < 0.05). CONCLUSION: These data support the findings that the COL1A1 gene polymorphism is associated with low BMD and fracture risk, and suggest a possible physiologic effect on total body turnover of type I collagen. (+info)
Intraoperative ultrasonography evaluation of posterior vertebral wall displacement in thoracolumbar fractures.
Intraoperative ultrasonography (IOUS) was used to evaluate the location and compressive effects of intraspinal fragments in thoracolumbar fractures and the efficacy of reduction maneuvers in patients operated on for isolated or attached intraspinal fragments or for global posterior wall disruption. Dynamic IOUS was used to evaluate the effects of traction and lordosis. Fifty-eight patients were evaluated using a 7.5 MHz ultrasound probe, including 27 treated by impaction, 19 by removal of apparently isolated fragments, and 12 by traction followed by lordosis for global posterior wall disruption. IOUS had limitations and problems caused by split fragments and residual pedicular attachments that can compromise intraoperative maneuvers. The risk of secondary displacement of isolated fragments treated by impaction was very high. In particular, the pinching effect produced by T-shaped fractures was commonly responsible for secondary displacement. IOUS evaluation of canal clearance after fragment removal was satisfactory, but did not provide quantitative data. IOUS was easier to perform and apparently more reliable than intraoperative myelography. The dynamic IOUS data suggest that, except for severely tilted fragments that are completely free or remain attached to a pedicle, residual discal attachments significantly influence the likelihood of successful reduction. (+info)
Pathological fracture of a lumbar vertebra caused by rheumatoid arthritis--a case report.
We describe a case of rheumatoid arthritis (RA) with collapse of the L3 lumbar vertebra for which surgery was performed. The pathogenesis of lumbar lesions affected by RA is discussed and the literature reviewed. (+info)
Exposure of medical personnel to methylmethacrylate vapor during percutaneous vertebroplasty.
The occupational exposure to methylmethacrylate (MMA) vapor during percutaneous vertebroplasty was determined. During five vertebroplasty procedures, air-sampling pumps were attached to medical personnel. MMA vapor levels in the samples were then quantified using gas chromatography. The samples collected yielded MMA vapor levels of less than five parts per million (ppm). The MMA vapor concentrations measured were well below the recommended maximum exposure of 100 ppm over the course of an 8-hour workday. (+info)
A high incidence of vertebral fracture in women with breast cancer.
Because treatment for breast cancer may adversely affect skeletal metabolism, we investigated vertebral fracture risk in women with non-metastatic breast cancer. The prevalence of vertebral fracture was similar in women at the time of first diagnosis to that in an age-matched sample of the general population. The incidence of vertebral fracture, however, was nearly five times greater than normal in women from the time of first diagnosis [odds ratio (OR), 4.7; 95% confidence interval (95% CI), 2.3-9.9], and 20-fold higher in women with soft-tissue metastases without evidence of skeletal metastases (OR, 22.7; 95% CI, 9.1-57.1). We conclude that vertebral fracture risk is markedly increased in women with breast cancer. (+info)
Effect of calcitonin on vertebral and other fractures.
We examined the incidence of vertebral and non-vertebral fractures in published randomised clinical trials using calcitonin by parenteral injection or intranasal spray. Trials were reviewed that compared calcitonin with placebo, no therapy, or calcium with or without vitamin D, and that mentioned fracture as an outcome. Studies that compared the effect of calcitonin with other active treatments were excluded. Fourteen trials with 1309 men and women were identified. In the calcitonin and the control groups, vertebral and non-vertebral fractures were summed and divided by the number of individuals originally allocated to the treatment groups. The relative risk of any fracture for individuals taking calcitonin versus those not taking calcitonin was 0.43 (95% CI 0.38-0.50). The effect was apparent for both vertebral fracture (RR 0.45; 95% CI 0.39-0.53) and non-vertebral fractures (RR 0.34; 95% CI 0.17-0.68). When studies identifying patients with fracture, rather than numbers of fractures were pooled, the magnitude of effect was less (RR 0.74; 95% CI 0.60-0.93), and the separate effects on vertebral and non-vertebral fractures was of borderline significance. We conclude that, within the limitations of this study, treatment with calcitonin is associated with a significant decrease in the number of vertebral and non-vertebral fractures. (+info)
Reducing the cervical flexion tear-drop fracture with a posterior approach and plating technique: an original method.
Flexion tear-drop fractures (FTDF) in the cervical spine constitute a highly unstable condition with a high incidence of neurological complications due to posterior displacement of the fractured vertebra in the spinal canal. The widely accepted surgical management for this condition includes complete excision and grafting of the vertebral body through an anterior approach. Thorough radiological and CT analysis of FTDF shows that the vertebral body is often separated into two parts by a sagittal plane fracture, but remains continuous through the pedicle and anterior arch of the vertebral foramen with the lateral mass and the articular processes. We therefore hypothesized that reduction would be possible by acting on the articular process through a posterior approach with a particular plating technique. Eight patients with FTDF were operated on with the technique we describe. Three had complete tetraplegia, four had incomplete tetraplegia and one was normal. A preoperative CT scan was made in all patients. Local kyphosis, posterior displacement of the vertebral body, and general lordosis in the cervical spine were recorded. In all cases, a satisfactory reduction was achieved on the postoperative radiographs and at the mean follow-up of 18.6+/-12.1 months, with residual posterior displacement being less than 1 mm. No complication occurred. Out of seven neurologically impaired patients, five showed some motor recovery at the latest follow-up. The posterior technique is described, and the rationale and pros and cons are discussed. The study showed that posterior reduction and fixation of flexion tear-drop fracture is not only possible, but permits an accurate restoration of the anatomy of the fractured cervical spine. (+info)
MR imaging for early complications of transpedicular screw fixation.
This series comprises ten patients treated with transpedicular screw fixation, who suffered early postoperative problems such as radicular pain or motor weakness. Besides plain radiographs, all patients were also evaluated with MR imaging. Three patients were reoperated for either repositioning or removal of the screws. MR images, especially T1-weighted ones, were very helpful for visualizing the problem and verifying the positions of the screws. In cases of wide areas of signal void around the screws, the neighboring axial MR images at either side, which have fewer artifacts, gave more information about the screws and the vertebrae. (+info)