1/351. Extension of phenotype associated with structural mutations in type I collagen: siblings with juvenile osteoporosis have an alpha2(I)Gly436 --> Arg substitution.Mutations in the type I collagen genes have been identified as the cause of all four types of osteogenesis imperfecta (OI). We now report a mutation that extends the phenotype associated with structural abnormalities in type I collagen. Two siblings presented with a history of back pain and were diagnosed with juvenile osteoporosis, based on clinical and radiological examination. Radiographs showed decreased lumbar bone density and multiple compression fractures throughout the thoracic and lumbar spines of both patients. One child has moderate short stature and mild neurosensory hearing loss. However, neither child has incurred the long bone fractures characteristic of OI. Protein studies demonstrated electrophoretically abnormal type I collagen in samples from both children. Enzymatic cleavage of rna:rna hybrids identified a mismatch in type I collagen alpha2 (COL1A2) mRNA. dna sequencing of COL1A2 cDNA subclones defined the mismatch as a single-base mutation (1715G --> A) in both children. This mutation predicts the substitution of arginine for glycine at position 436 (G436R) in the helical domain of the alpha2(I) chain. Analysis of genomic dna identified the mutation in the asymptomatic father, who is presumably a germ-line mosaic carrier. The presence of the same heterozygous mutation in two siblings strongly suggests that the probands display the full phenotype. Taken together, the clinical, biochemical, and molecular findings of this study extend the phenotype associated with type I collagen mutations to cases with only spine manifestations and variable short stature into adolescence.- - - - - - - - - - ranking = 1keywords = bone (Clic here for more details about this article) |
2/351. Eighteen fractures in a man with profound mental retardation.A 39-year-old man with generalized tonic clonic epilepsy and profound mental retardation sustained 18 fractures (15 in appendicular and 3 in axial bones) during 19 years. Both femoral necks were fractured, requiring surgical repair. Although he had been on antiepileptic drugs for 35 years, he had no radiographic or biochemical sign of osteomalacia. He had a very low bone mineral density, suggesting osteoporosis. This case illustrates an important medical problem affecting people with developmental disability and a management challenge for their caretakers.- - - - - - - - - - ranking = 1keywords = bone (Clic here for more details about this article) |
3/351. pregnancy-associated osteoporosis with elevated levels of circulating parathyroid hormone-related protein: a report of two cases.Two lactating women who had complained of back pain developed spontaneous vertebral fractures with low bone mineral density (BMD) several months postpartum. The back pain and biochemical abnormalities presented as hypercalcemia and elevated plasma levels of the parathyroid hormone-related protein (PTH-rP) that returned to normal indices with increasing BMD after weaning. The increased circulating PTH-rP might contribute to the pregnancy-associated osteoporosis in women who probably are already osteopenic.- - - - - - - - - - ranking = 0.5keywords = bone (Clic here for more details about this article) |
4/351. Insufficiency fractures, an often unrecognized diagnosis.diagnosis of sacral insufficiency fractures is difficult since the onset is mild, and usually discomfort is attributed to degeneration of the lumbar spine. Computed tomography and radionuclide bone scans are helpful in making the diagnosis, as regular X-ray and magnetic resonance imaging usually fail to demonstrate the fracture.- - - - - - - - - - ranking = 0.5keywords = bone (Clic here for more details about this article) |
5/351. Severe progressive osteoporotic spine deformity with cardiopulmonary impairment in a young patient. A case report.STUDY DESIGN: This report describes a young patient with a rapidly progressive kyphosis caused by collapse of a severely osteoporotic thoracolumbar spine, which led to impairment of cardiopulmonary function. OBJECTIVES: To highlight the treatment strategy, difficulty of diagnosis, operative stabilization, and outcome. SUMMARY OF BACKGROUND DATE: Little is known about natural history, treatment options, and results of this condition. methods: The magnitude of bone loss was measured by dual-energy x-ray absorptiometry, and the deformity was visualized by computed tomography and magnetic resonance imaging. Laboratory investigations also were performed before and during halotraction in an attempt to establish a diagnosis. These data constituted the preoperation information required to assess later results of medical and surgical intervention. RESULTS: An extensive evaluation of possible underlying etiologies failed to identify a specific etiology. Before and during halotraction, bone mineral substitutes were given, partially correcting the bone mineral content as measured on repeated dual-energy x-ray absorptiometry scans. In addition, the thoracic kyphosis was partially corrected, from 100 degrees to 70 degrees Cobb's angle. Subsequently, a combined anterior and posterior stabilization was performed from C7 to S1 using a vascularized fibula graft, a double Isola rod system (AcroMed, Cleveland, OH), and a carbonate apatite cancellous bone cement to reinforce the pedicle screws. At follow-up assessment 40 months surgery, the patient was asymptomatic and fully mobilized, with radiographs showing complete incorporation of the grafts and no loosening of the fixation device. CONCLUSIONS: The diagnostic and therapeutic difficulties of progressive spine deformity caused by severe osteoporosis in young patients emphasizes the importance of a thoroughly planned treatment strategy. Halotraction is recommended to stop progression of the deformity, or even partially correct it, and to allow time to search for the diagnosis and bone mineral substitution. Surgical treatment using vascularized fibular strut grafts and a strong fixation device was successful. Biocompatible carbonated apatite cancellous bone cement was successfully used to reinforce pedicle screw fixation.- - - - - - - - - - ranking = 3keywords = bone (Clic here for more details about this article) |
6/351. Mesomelic dysplasia with periosteal thickening, radio-humeral dislocation, osteoporosis and multiple fractures.We report a boy with a new form of mesomelic dysplasia characterised by short stature, multifocal periosteal thickening, radio-humeral dislocation, osteoporosis and multiple fractures with minimal trauma. electrophoresis of fibroblast collagens detected defects in type III and type V collagen. CONCLUSION: Bone dysplasias presenting with osteopenia, abnormal trabecular pattern, bone fragility, and periosteal thickening suggest a collagenopathy. A possible collagen defect requires biochemical investigations.- - - - - - - - - - ranking = 0.5keywords = bone (Clic here for more details about this article) |
7/351. Oral contraceptives: therapeutic uses and quality-of-life benefits--case presentations.Numerous studies have shown that oral contraceptives (OC) provide protection against a wide variety of illnesses and conditions, including loss of bone density, ovarian cysts, menstrual cycle irregularities, dysmenorrhea and menorrhagia, ectopic pregnancy, pelvic inflammatory disease, benign breast disease, endometrial cancer, and ovarian cancer. How OC can be used not only for contraception but also to improve health among women throughout their reproductive years is illustrated by four case presentations: an adolescent with menstrual problems; a 25-year-old mulligravida who wishes to delay childbearing; a 35-year-old who has completed her family and requests tubal ligation; and a 45-year-old with perimenopausal symptoms. In view of their numerous health benefits, OC are to reproductive-age women as hormone replacement therapy is to menopausal women.- - - - - - - - - - ranking = 0.5keywords = bone (Clic here for more details about this article) |
8/351. Menstrual irregularities associated with athletics and exercise.For women and girls, and dangers of excessively rigorous exercise regimens can include disturbances in reproductive function and a negative impact on bone density. Assisting female patients in finding a balance between the benefits and potential dangers of exercise is an important role for health professionals.- - - - - - - - - - ranking = 0.5keywords = bone (Clic here for more details about this article) |
9/351. Rapid improvement of osteoporosis following parathyroidectomy in a premenopausal woman with acute primary hyperparathyroidism.We describe a premenopausal white woman with symptomatic acute primary hyperparathyroidism and marked osteoporosis. After undergoing a parathyroidectomy, the patient experienced not only rapid symptomatic relief, but also marked improvement in bone mineral density, which increased by 25% in the hip and by 22% in the lumbar spine 1 year after the surgery. Acute primary hyperparathyroidism should be considered in any patient with severe symptomatic hypercalcemia. Appropriate treatment with early parathyroidectomy can result in significant and rapid improvement in bone mineral density.- - - - - - - - - - ranking = 1keywords = bone (Clic here for more details about this article) |
10/351. blindness from bad bones.Progressive visual loss is the most common neurologic finding in osteopetrosis. Several mechanisms may explain this phenomenon, including compression of the optic nerves caused by bony overgrowth of the optic canals and retinal degeneration. We report a child with osteopetrosis and progressive visual loss, even though patent optic canals were demonstrated by computed tomography and digital holography. This patient's visual loss was caused by increased intracranial pressure secondary, to obstruction of cerebral venous outflow at the jugular foramen. This case points to the importance of a full evaluation of the skull base foramina in the diagnostic workup of visual loss in patients with osteopetrosis.- - - - - - - - - - ranking = 2keywords = bone (Clic here for more details about this article) |
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