A 53-year-old male presented with a rare dorsally sequestrated thoracic disc herniation manifesting as acute low back pain and weakness. He had no history of trauma. Magnetic resonance (MR) imaging demonstrated a mass at T10-11 intervertebral level connected with the T-10 disc. Axial MR imaging showed the mass had surrounded and compressed the dural sac from the lateral and dorsal sites. MR imaging with gadolinium-diethylenetriaminepenta-acetic acid showed slight rim enhancement of the lesion. Computed tomography detected no abnormal calcification. The diagnosis was thoracic disc herniation. Laminectomy resulted in rapid and satisfactory recovery. The histological diagnosis was thoracic disc herniation. MR imaging was very effective for the diagnosis based on the connection between the mass and the disc space. The differential diagnosis includes metastatic epidural tumor, epidural hematoma, and epidural abscess. (+info)
Stage-specific homeotic vertebral transformations in mouse fetuses induced by maternal hyperthermia during somitogenesis.
(26/1662)
To investigate the heat shock effects upon somitogenesis and specification of the vertebral identity, pregnant ICR mice were briefly exposed to 42 degrees C or 43 degrees C at E7.5, E8.5, or E9.5 (noon of the plug day = E0.5). Heat treatment induced embryonic day-specific vertebral transformations whose frequency and severity were dependent on the temperature elevation. Following a heat treatment at E8.5, the vertebral identity of T6 through S1 was shifted anteriorly by one or two segments (posterior transformations). Such shifts were found in more than one-third of the fetuses heat-stressed at 42 degrees C, and in over 90% of those exposed to 43 degrees C. When heated at E7.5, the anterior boundary of vertebral transformations was shifted cranially to cervical levels (C1-C7), and when heated at E9.5, it was shifted caudally to the lower thoracic and lumbar levels (T13-L4). Examination of Hox gene expression domains by in situ hybridization showed that the anterior boundaries of Hoxa-5, Hoxa-7, Hoxc-8, and Hoxc-9 expression domains in the paraxial mesoderm were shifted cranially by one somite segment in embryos heated at E7.5, as compared with the corresponding levels of their expression in control embryos. Such cranial shifts were found for Hoxa-7, Hoxc-8 and Hoxc-9, but not for Hoxa-5, in embryos heated at E8.0. In embryos heated at E8.5, only the expression domains for Hoxc-8 and Hoxc-9 were found to be shifted. The observed stage-specific vertebral transformations and shifts of the Hox gene expression domains were consistent with the temporal colinearity and posterior predominance of Hox gene expression during development. Further histological and cytochemical analyses revealed that heat-induced vertebral transformations may not be a result of induced cell death, but heat-induced transient arrest of cell proliferation and somitogenesis could result in altered expression of Hox genes and subsequently produce vertebral transformations. (+info)
Evolution of chronic recurrent multifocal osteitis toward spondylarthropathy over the long term.
(27/1662)
OBJECTIVE: To retrospectively assess, with a sufficiently long followup (mean 11.6 years; median 9 years), the long-term outcome of chronic recurrent multifocal osteitis (CRMO), a multifocal, inflammatory bone disease. METHODS: Patients included were 8 children/adolescents and 7 adults with no family history of rheumatic disease who had been diagnosed as having CRMO between 1979 and 1995. Ten patients had undergone at least 1 bone biopsy of the lesions, with histologic examination and multiple cultures. In 1996, in addition to an in-depth interview, 12 patients underwent an extensive physical examination, laboratory evaluation, HLA-A, B, C, and DR typing, bone radiography and scintigraphy, and computed tomography scan of the sternoclavicular and sacroiliac joints. RESULTS: Remission was observed in 3 patients. The other 12 patients developed various associations of vertebral (n = 10), sacroiliac (n = 6), anterior thoracic (n = 7), peripheral articular (n = 2), enthesopathic (n = 4), or dermatologic (palmoplantar pustulosis in 3 cases and psoriasis in 2) involvements. Spine involvement was the most common and occurred the earliest (median time to appearance after the onset of osteitis 5.63 years). Clinical sacroiliitis was always unilateral. No patients carried the HLA-B27 haplotype. CRMO responded well to nonsteroidal antiinflammatory drugs. Twelve patients met the European Spondylarthropathy Study Group criteria for spondylarthopathy. CONCLUSION: After 10 years, CRMO had usually evolved to spondylarthropathy, but with certain features not usually seen in the latter: predominantly, unilateral sacroiliitis, no familial form, and no link with HLA-B27. (+info)
Possible intraspinal metastasis of a canine spinal cord nephroblastoma.
(28/1662)
A 2-year-old Basset Hound was admitted to the University of Florida Veterinary Medical Teaching Hospital with progressive spastic paraparesis. At necropsy, intradural extramedullary tumors produced areas of spinal cord swelling and softening in spinal cord segments T11-T12 and L4-L6. Histologic examination of the masses revealed sheets of polygonal blastemal cells, epithelial cells forming tubules and rosettes, and embryonal glomeruloid-like structures in the thoracic mass. Cells in the lumbar mass were less differentiated, forming rare tubules and no glomeruloid-like structures. The occurrence of two tumors in the spinal cord along with the less differentiated appearance of the lumbar tumor raises the possibility that the lumbar mass arose as a result of intraspinal metastasis. To our knowledge, this is the first report of multifocal or metastatic canine spinal nephroblastoma. In addition, the vimentin and cytokeratin immunohistochemical staining characteristics of these spinal cord nephroblastomas are described. (+info)
The prevalence of vertebral fractures in mild ankylosing spondylitis and their relationship to bone mineral density.
(29/1662)
OBJECTIVE: To determine bone mineral density (BMD) in patients with mild ankylosing spondylitis (AS), to establish the prevalence of vertebral fractures and fracture risk in these patients, and to determine the relationship between BMD and vertebral fractures. METHODS: Sixty-six men with mild AS were studied. BMD of the lumbar spine and femoral neck was measured by dual X-ray absorptiometry (DXA) and radiographs of the thoracic and lumbar spine were obtained in all subjects. From the radiographs, vertebral fractures were characterized by a morphometric technique using established criteria. Thirty-nine healthy male subjects aged 50-60 yr, recruited from primary care registers, had spinal radiographs performed and served as controls for vertebral fractures. RESULTS: In patients with AS, BMD was reduced in both the lumbar spine 0.97 (0.1) g/cm(2) [T score -1.10 (1.3), 95% confidence interval (CI) -0.50, +0.14] and femoral neck 0.82 (0.1) g/cm(2) [T score -1.40 (1.2), 95% CI -0.51, +0.09]. There was no correlation between BMD of either the lumbar spine or femoral neck and duration of disease in patients with AS. Eleven of 66 (16.7%) patients with AS had a vertebral fracture, compared with one of 39 (2.6%) controls; odds ratio 5.92 (95% CI 1.4, 23.8). AS patients with fractures were not significantly older (mean age 41.4 vs 37.8 yr, P=0.17), but had significantly longer disease duration (12.4 vs 9.3 yr, P<0.05) than patients without fractures. No significant difference was found in the visual analogue scores for pain in AS patients with fractures compared with those without. No significant correlation was observed between BMD of the lumbar spine or femoral neck and vertebral fractures in patients with AS. In addition, there was no significant difference in the lumbar spine or femoral neck BMD in AS patients with fractures compared with those without. CONCLUSIONS: Spinal and hip osteopenia and vertebral fractures are a feature of mild AS. However, there was no correlation between BMD and vertebral fractures in these patients. AS patients with mild disease had a higher risk of fractures compared with the normal population and this increased with the duration of disease. (+info)
Sagittal static imbalance in myelomeningocele patients: improvement in sitting ability by partial and total gibbus resection.
(30/1662)
The progression of kyphosis in myelomeningocele is independent of skeletal growth and requires early operative correction and stabilization to prevent a loss of sitting ability. In severe cases, only vertebrectomy makes it possible to achieve correction, stability and skin-closure without tension. In 14 patients with myelomeningocele gibbus, kyphectomy was performed, removing two vertebral bodies on average. The average kyphosis angle decreased from 128 degrees to 81 degrees, enabling most of the patients to participate again in social life by restoring wheelchair mobility. Nevertheless, a significantly higher complication rate was found compared to other correctional operations, lengthening the average hospital stay to 41 days. Special problems arose from trophic disorders of the skin and soft tissue and from the dystrophic muscles below the level of neural malfunction. In three cases, kyphosis reappeared cranial to the fused segments, requiring ventral stabilization. With respect to increasing kyphosis angle, an early intervention should be aimed at. A secondary operation can be necessary, if surgery is performed without taking care of the growth potential. (+info)
Recombinant bone morphogenetic protein-7 as an intracorporal bone growth stimulator in unstable thoracolumbar burst fractures in humans: preliminary results.
(31/1662)
The study presented here is a pilot study in five patients with unstable thoracolumbar spine fractures treated with transpedicular OP-1 transplantation, short segment instrumentation and posterolateral fusion. Recombinant bone morphogenetic protein-7 in combination with a collagen carrier, also referred to as OP-1, has demonstrated ability to induce healing in long-bone segmental defects in dogs, rabbits and monkeys and to induce successful posterolateral spinal fusion in dogs without need for autogenous bone graft. Furthermore OP-1 has been demonstrated to be effective as a bone graft substitute when performing the PLIF maneuver in a sheep model. Five patients with single-level unstable burst fracture and no neurological impairment were treated with intracorporal OP-1 transplantation, posterior fixation (USS) and posterolateral fusion. One patient with osteomalacia and an L2 burst fracture had an additional intracorporal transplantation performed proximal to the instrumented segment, i.e. OP-1 into T 12 and autogenous bone into T 11. Follow-up time was 12-18 months. On serial radiographs, Cobb and kyphotic angles, as well as anterior, middle and posterior column heights, were measured. Serial CT scans were performed to determine the bone mineral density at fracture level. In one case, radiographic and CT evaluation after 3 and 6 months showed severe resorption at the site of transplantation, but after 12 months, new bone had started to fill in at the area of resorption. In all cases there was loss of correction with regard to anterior and middle column height and sagittal balance at the latest follow-up. These preliminary results regarding OP-1 as a bone graft substitute and stimulator of new bone formation have been disappointing, as the OP-1 device in this study was not capable of inducing an early sufficient structural bone support. There are indications to suggest that OP-1 application to a fracture site in humans might result in detrimental enhanced bone resorption as a primary event. (+info)
Short segment fixation of thoracolumbar burst fractures without fusion.
(32/1662)
There continues to be controversy surrounding the management of thoracolumbar burst fractures. Numerous methods of fixation have been described for this injury, but to our knowledge, spinal fusion has always been part of the stabilising procedure, whether this involves an anterior or a posterior approach. Apart from an earlier publication from this centre, there have been no reports on the use of internal fixation without fusion for this type of fracture. The aim of the study was to determine the outcome of patients with thoracolumbar burst fractures who were treated with short segment pedicle screw fixation without fusion. This is a retrospective review of 28 consecutive patients who had short segment pedicle screw fixation of thoracolumbar burst fractures without fusion performed between 1990 and 1993. All patients underwent a clinical and radiological assessment by an independent observer. Outcome was measured using the Low Back Outcome Score. The minimum follow-up period was 2 years (mean 3.1 years). Fifty percent of patients achieved an excellent result with the Low Back Outcome Score, while 12% were assessed as good, 20% fair and 16% obtained a poor result. The only significant factor affecting outcome was the influence of a compensation claim (P < 0.05). The implant failure rate (14% of patients) and the clinical outcome was similar to that from series where fusion had been performed in addition to pedicle screw fixation. The results of this study support the view that posterolateral bone grafting is not necessary when managing patients with thoracolumbar burst fractures by short segment pedicle screw fixation. (+info)