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Query: UMLS:C0729233 (Thoracic)
 6,478 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A biomechanical model of the human thorax was constructed to investigate how asymmetric growth of the thorax might initiate spinal lateral curvature and axial rotation as seen in scoliosis deformities. Geometric data specifying nodal points of the model were taken from stereo-radiographs of an adolescent subject. An initially symmetrical geometry was created by 'mirroring' measurements of a hemi-thorax and spine. Published data provided cross-sectional measurements of the ribs, material properties of tissues and global flexibilities of the intervertebral motion segments. The ribs, sternum, intervertebral motion segments and intercostal ligaments were represented by elastic elements. Model deformations were calculated by the direct stiffness finite element method, with growth represented by an initial strain term in the constitutive law. Non-linear behavior was accommodated by running the model recursively, with updated node locations at each step. Both stress relaxation and stress modulation of growth in the component tissues were simulated. Thoracic growth of 20% with asymmetric growth of the ribs was simulated to give rib length asymmetries of 11%. similar to that observed in a previous study of patients with idiopathic scoliosis. This resulted in the model having a small thoracic scoliosis curvature convex toward the side of the longer ribs. Variations of the model which permitted free motion at the costo-vertebral joints or produced changes in the curvature of the posterior parts of the ribs resulted in axial rotation of the vertebrae similar to that observed clinically. The model supports the idea that growth asymmetry could initiate a small scoliosis during adolescence.
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PMID:Three-dimensional osseo-ligamentous model of the thorax representing initiation of scoliosis by asymmetric growth. 234 20

The natural history of scoliosis, or lateral curvature of the spine, was followed up in 135 patients (111 girls, 24 boys) for a total average period of 52.4 months. We observed patients with a curvature of between 5 degrees and 30 degrees none of whom had been treated specifically as orthotics or with electrical stimulation or by surgery. Two groups of patients with progressive curvature were differentiated: 1) in 62.2% of the patients the curvature progressed by more than 5 degrees during the entire observation period; 2) in 36% of the patients we found an increase in curvature by more than 5 degrees within one year. Another result of our study was that idiopathic scoliosis is particularly dangerous in young patients with a "0" Risser sign. Thoracic curvatures and double major curvatures were more liable to progress than lumbar and thoracolumbar curvatures. Even a small angle of curvature in young patients must be taken seriously.
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PMID:[The progression of untreated idiopathic scoliosis in the x-ray image]. 255 24

Significant spinal abnormalities were found in eight patients (average age of 6 years, 5 months) with camptomelic dysplasia. The late ossification of the midthoracic pedicles served as a clear diagnostic criterion for the syndrome. Scoliosis averaging 63 degrees was found in all seven nonquadriplegic cases. Thoracic hyperkyphosis averaging 126 degrees was seen in six (75%) of the patients, while cervical kyphosis averaging 66 degrees was noted in three (38%). Vertebral body hypoplasia appeared to be a major cause of deformity. This study clarifies that patients with camptomelic dysplasia are surviving longer than previously expected and therefore should have their spinal deformities treated aggressively.
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PMID:Spinal abnormalities in camptomelic dysplasia. 264 5

Limb-Body Wall Complex is a complicated fetal malformation with the essential features of neural-tube defects, body-wall disruption, and limb abnormalities. This complex should be distinguished from other body-wall defects including omphalocele and gastroschisis since the prognosis for limb-body wall complex is uniformly poor. For 13 cases of this unusual fetal anomaly, sonographic, radiologic, and pathologic findings were correlated. Thoracic or abdominal body-wall defects, neural-tube abnormalities, severe scoliosis, positional deformities, and abnormalities of fetal membranes were consistently demonstrated on in utero sonograms. Results show that the diagnosis of limb-body wall complex can be made by prenatal sonography.
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PMID:Limb-body wall complex: in utero sonographic diagnosis of a complicated fetal malformation. 293 58

The authors reviewed 43 patients with the onset of idiopathic scoliosis between 4 and 9 years who were followed to skeletal maturity to document the natural history, effects of bracing, and factors associated with progression. Average age at onset was 7.1 years for female and 6.7 for male patients. Twelve were treated with observation only; six improved, five progressed, and one refused an orthosis and required surgery. Thirty-one patients wore an orthosis; five patients improved or were unchanged, and 26 progressed, including 13 who subsequently required surgery. All patients treated with observation had a rib vertebral angle difference (RVAD) of less than 10 degrees; whereas patients progressing despite orthosis and all but one patient requiring operation had an RVAD greater than 10 degrees. Thoracic hypokyphosis (less than 20 degrees) was present in 20% of observed patients, 64% of those treated with an orthosis, and 78% of those requiring operation.
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PMID:Juvenile idiopathic scoliosis followed to skeletal maturity. 320 64

Curve behavior of idiopathic scoliosis in an exclusively male population was investigated, since it has not been previously reported. Fifty males with idiopathic scoliosis satisfied entry requirements for this study: standing posteroanterior (PA) spine radiograph measuring a curve greater than 20 degrees, preoperative observation for greater than 1 year (mean, 4.4 years), and nonoperative patients with greater than 5 years of radiographic follow-up beyond skeletal maturity (mean, 10.7 years). Mean rate of curve progression from presentation to Risser 4 maturation was 3.0 degrees/year. Forty-four percent of the curves progressed 5 degrees or more between Risser 4 and 5. The rate of curve progression following Risser 5 was 0.18 degrees/year. Thoracic curves were associated with a higher degree of curve progression than other curve types (P less than 0.05). There was no statistically significant association between curve progression and family history, vertebral rotation, Risser sign, or curve magnitude. Curve progression secondary to growth usually terminates at Risser 4 in females with idiopathic scoliosis. This study indicated that scoliotic male curves demonstrated clinically significant progression until Risser 5 rather than Risser 4. Thus, the authors conclude that males with idiopathic scoliosis curves greater than 20 degrees should be followed radiographically until Risser 5. In females, scoliosis beyond Risser 4 can be considered as an adult curve; however, in males, scoliosis can be evaluated as an adult curve only after Risser 5. Beyond Risser 5, male curves demonstrate minimal progression.
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PMID:Idiopathic scoliosis in males. A natural history study. 320 65

Thoracic computed tomography was performed in 32 patients who had undergone thoracoplasty as part of their treatment for pulmonary tuberculosis. Pleural thickening and the prevalence of bronchiectasis were more marked in the operated hemithorax. Bullae were more prevalent in the operated hemithorax but the difference was not statistically significant. In all but one patient, scoliosis was present. Illustrative examples are presented to demonstrate the range of appearances following this operation.
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PMID:Appearances on computed tomography following thoracoplasty for pulmonary tuberculosis. 326 11

The essential lesion in idiopathic scoliosis is a lordosis at the curve apex. For the rotational instability provided by a lordosis to progress, asymmetry must be present in another plane. A biomechanical analysis of spinal shape demonstrates a delicate balance between the median, transverse, and coronal planes. The normal cervical and lumbar lordosis which are inherently rotationally unstable are protected by: a) prismatic shaped vertebral bodies with their bases anterior, b) considerable available intersegmental flexion, and c) powerful posterior soft tissue support. In contrast, the thoracic vertebral bodies are shaped as prisms with their apices anterior. This rotationally unstable configuration is protected by a kyphosis with the axis of spinal rotation situated anteriorly. The thoracic vertebral prisms are asymmetric, their apices lying to the right of the median plane. In the presence of a lordosis the apices of the prisms will be directed toward the right producing a right-sided scoliosis. Any significant degree of left-sided coronal asymmetry can override the influence of the transverse plane and therefore left-sided curves are not uncommon. Thoracic idiopathic scoliosis is located at T8/T9 and the lordosis here is often an upward continuation of the normal lumbar lordosis such that the asymmetric thoracic prisms are no longer protected.
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PMID:The anatomy of spinal deformity: a biomechanical analysis. 361 84

A total of 187 random cases of untreated idiopathic scoliosis, seen from a minimum of 15 to a maximum of 47 years after the end of growth, were reviewed. All curves increased after skeletal maturity (average progression: 0.4 degrees per year). Thoracic curves tend to progress more than lumbar, lumbar more than thoracolumbar, and thoracolumbar more than double major curves. Pain was present in 114 cases (61%) and appeared more frequently in women, after pregnancies, and with fatigue. Cardiopulmonary symptoms were present in 42 patients (22%), especially those with thoracic and thoracolumbar curves greater than 40 degrees. Psychologic disturbances were found in 35 cases (19%), mostly female patients with thoracic curves greater than 40 degrees. The cosmetic appearance of these patients at long-term follow-up was better compared with that at the end of growth, even though the curves progressed. Patients with decompensation of the trunk at the end of growth seemed to improve with time. In an unselected group of patients with severe curves a mortality rate of 17% was found, twice as much as in the Italian general population.
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PMID:Natural history of untreated idiopathic scoliosis after skeletal maturity. 381 Feb 93

In an attempt to find prognostic factors for mild scoliosis, the first clinical and radiologic data of 159 subjects with idiopathic scoliosis less than 30 degrees were correlated with the annual speed of progression estimated graphically by further examinations. Thoracic and double major are more progressive than thoracolumbar and lumbar. The correlation with rate of progression is better for supine angle than for standing angle. Curves with low supine angles are those that have great relative collapse and low risk of progression. Only the rib hump of thoracic and thoracolumbar are correlated with evolutivity. Predictive equations give less approximation for individual prognosis than a previous graphic method, so they are not used. Approximately 73% of scoliosis have evolutivities less than 6 degrees per year and required nocturn corrective treatment.
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PMID:Scoliosis at less than 30 degrees. Properties of the evolutivity (risk of progression). 404 8


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