1/124. 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 = fracture (Clic here for more details about this article) |
2/124. Type I osteogenesis imperfecta: diagnostic difficulties.A 65-year-old woman presented with vertebral fractures of the lumbar spine and a history of pathological fractures following minor trauma, which had occurred before the onset of menopause. Her past medical history was significant for intermittent low back pain since childhood, which was attributed to thoracolumbar scoliosis. A diagnosis of unclassifiable osteoporosis was made until invasive diagnostic procedures suggested a mild form of type I osteogenesis imperfecta (OI). In unclear or atypical perimenopausal osteoporosis and diagnosis of OI should be considered.- - - - - - - - - - ranking = 1keywords = fracture (Clic here for more details about this article) |
3/124. Co-existence of osteogenesis imperfecta and hyperparathyroidism.osteogenesis imperfecta (OI) and hyperparathyroidism (HTP) are disorders affecting the skeletal system and calcium metabolism not evidently related to one another. We report a case in which both OI and HPT were present. Our female patient presented with hypercalcaemia (S-Ca2 1.59 mmol/l; normal range 1.15-1.30) and 4-gland parathyroid hyperplasia at 30 years of age. Since her first year she had fractures, blue sclera, hypermobile joints, short stature (height 1.51 m, weight 49.5 kg) but normal hearing, and dentiogenesis imperfecta (tooth disease caused by defective formation of dentin) was absent. This patient bears many similarities with the 5 patients reported previously but it is the only patient, to our knowledge, with OI and early onset of HPT (30 year old female). We have found the OI to be type 1. A minor improvement of the rate of bone turnover 10 months after parathyroidectomy indicates the HPT to be primary and suggests the OI type 1 and pHPT to be two different calcium metabolic diseases incidentally occurring in the same patient.- - - - - - - - - - ranking = 0.5keywords = fracture (Clic here for more details about this article) |
4/124. Two sibs with an unusual pattern of skeletal malformations resembling osteogenesis imperfecta: a new type of skeletal dysplasia?We report a 6 year old boy with multiple fractures owing to bilateral, peculiar, wave-like defects of the tibial corticalis with alternative hyperostosis and thinning. Furthermore, he had Wormian bones of the skull, dentinogenesis imperfecta, and a distinct facial phenotype with hypertelorism and periorbital fullness. Collagen studies showed normal results. His sister, aged 2 years, showed the same facial phenotype and dental abnormalities as well as Wormian bones, but no radiographical abnormalities of the tubular bones so far. The mother also had dentine abnormalities but no skeletal abnormalities on x ray. This entity is probably the same as that described in a sporadic case by Suarez and Stickler in 1974. In spite of the considerable overlap with osteogenesis imperfecta (bone fragility, Wormian bones, and dentinogenesis imperfecta), we believe this disorder to be a different entity, in particular because of the unique cortical defects, missing osteopenia, and normal results of collagen studies.- - - - - - - - - - ranking = 0.5keywords = fracture (Clic here for more details about this article) |
5/124. bone density measurements by computed tomography in osteogenesis imperfecta type I.The objectives of this study were (1) to determine whether there are differences in bone density in children versus adults with osteogenesis imperfecta type I (OI-type I) using computed tomography (CT) bone density measurements, (2) to determine whether there are differences in bone density between normal infants and infants with OI-type I using CT bone density measurements and (3) to determine whether CT bone density measurements could be helpful in investigating the infant with unexplained fractures. CT bone density measurements determine both the cortical bone density (CBD) and the trabecular bone density (TBD). CT bone density was determined using the OsteoQuant in 14 individuals with OI-type I who ranged in ages from 8 months to 45 years. The control groups consisted of over 1000 normal individuals, mostly adults, and included 7 normal infants who ranged in age from 10 months to 27 months. One of the individuals with OI-type I was a 4-month-old infant with multiple, unexplained fractures who had no other features of OI-type I and whose parents were accused of child abuse. Infants and children with OI-type I had low CBD and low TBD compared with normal controls, whereas adults with OI-type I had low TBD and high CBD when compared with controls. The one infant with multiple unexplained fractures and no other features of OI-type I had a bone density profile suggesting OI-type I with a low TBD and low CBD. Subsequent collagen analysis showed biochemical evidence of OI-type I. Individuals with OI-type I have abnormal CT bone density profiles that evolve over time from a low CBD and low TBD during infancy and childhood to a high CBD and low TBD during adulthood. This may explain the decreased frequency of fractures in individuals with OI-type I in adulthood compared with childhood. Individuals with OI-type I can present with only multiple unexplained fractures and have no other clinical features to strongly suggest the diagnosis. CT bone density measurements can be helpful in these atypical cases of OI-type I and should be considered in the investigation of the infant with unexplained fractures to help distinguish intrinsic bone disease from child abuse.- - - - - - - - - - ranking = 3keywords = fracture (Clic here for more details about this article) |
6/124. Chest compressions in an infant with osteogenesis imperfecta type II: No new rib fractures.The case report of a newborn female with osteogenesis imperfecta type II who underwent cardiopulmonary resuscitation (CPR) with manual chest compressions for several minutes is presented. Chest radiographs taken before and after the chest compressions were administered were reviewed by several radiologists from 3 different hospitals and demonstrated no new radiographically visible rib fractures. Collagen analysis, the patient's clinical appearance, and clinical course, as well as a consultant's opinion aided in confirmation of the diagnosis of osteogenesis imperfecta type II. A review of 4 previous studies concerning rib fractures and CPR is included. This unique case supports previous articles that have concluded that rib fractures rarely, if ever, result from CPR in pediatrics, even in children with a lethal underlying bone disease, such as osteogenesis imperfecta type II. cardiopulmonary resuscitation, chest compressions, osteogenesis imperfecta, rib fractures, bone disease.- - - - - - - - - - ranking = 4keywords = fracture (Clic here for more details about this article) |
7/124. A case of chondrodysplasia punctata with features of osteogenesis imperfecta type II.The osteogenesis imperfecta syndromes constitute a group of heterogeneous, heritable skeletal dysplasias. Of the 4 types, type II is the most severe, with an incidence of 1 per 55,000. It is characterized by malformed bones secondary to abnormal collagen type i synthesis. Affected fetuses are divided into 3 groups: A, B, and C. All groups have long bones described as "wrinkled" or "crumpled" secondary to repeated fractures. Many bones also show evidence of demineralization, which is especially evident in the bones of the face and calvaria. In groups A and C, the chest is generally small, with thickened and shortened ribs, and each rib has characteristic "beading" patterns secondary to repeated fracturing. Sonography has traditionally been successful in the diagnosis of osteogenesis imperfecta at an early gestational age. chondrodysplasia punctata describes a heterogeneous group of skeletal disorders characterized by abnormal mineralization of bones during gestation. There are many different causes of it, but some of the specific subtypes include rhizomelic, X-linked dominant (also known as Conradi-Hunermann syndrome), X-linked recessive, and tibia-metacarpal. We report a case of severe X-linked dominant chondrodysplasia punctata, which sonographically had common features with osteogenesis imperfecta type II.- - - - - - - - - - ranking = 0.5keywords = fracture (Clic here for more details about this article) |
8/124. osteogenesis imperfecta in pregnancy: two case reports and review of literature.osteogenesis imperfecta (OI) is an inherited disease where basic pathology is of defective maturation of collagen. It is more common in women, and the incidence in pregnancy is 1 in 25,000 to 30,000. A multidisciplinary approach is necessary. Ideally, genetic counseling is sought before conception. Once pregnant, prenatal diagnosis can be established by chorion villous sampling. Serial scans would identify the affected fetus with fractures. A cesarean delivery is advocated if the fetus is affected or if the mother has pelvic fractures. An experienced anesthetist should be involved. Because these women are more likely to have a postpartum hemorrhage due to uterine atony, Syntocinon infusion and close observation in the third stage is indicated.- - - - - - - - - - ranking = 1keywords = fracture (Clic here for more details about this article) |
9/124. Cardiac reoperation in a patient with osteogenesis imperfecta: a case report.A case of a 40-year-old man with dehiscence of the prosthetic aortic valve and recurrence of mycotic aneurysm of the left ventricular outflow tract with osteogenesis imperfecta is presented. He had an operation of aortic valve replacement and direct closure of the mycotic aneurysm for infective endocarditis twenty-one months ago. We performed reoperation of prosthetic aortic valve, patch closure of the mycotic aneurysm and graft replacement of the ascending aorta. He was complicated with multiple fractures of bilateral scapla and dislocation of left shoulder one postoperative day. Fortunately, cardiac reoperation was performed successfully in this patient despite anticipated difficulties with tissue friability with osteogenesis imperfecta.- - - - - - - - - - ranking = 0.5keywords = fracture (Clic here for more details about this article) |
10/124. Technique of exchange of Sheffield telescopic rod system.Intramedullary fixation of long bones in patients with osteogenesis imperfecta has become the gold standard for prevention and treatment of fractures and subsequent deformities. The use of expanding rods has reduced the number of operations needed compared with fixed-length rods, allowing the growth of bones. The authors describe the technique of exchange of a Sheffield rod in a child in whom the bone has outgrown the rod length to the point where the rod is about to disengage or has just done so. The minimally invasive technique adds to the advantages already described for the Sheffield rod system over others in patients with osteogenesis imperfecta.- - - - - - - - - - ranking = 0.5keywords = fracture (Clic here for more details about this article) |
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