Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “EXOSTOSES”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 631 records · Page 35Linked to original sources

Multiple cartilaginous exostosis in a Golden Retriever cross-bred puppy. Clinical, radiographic and backscattered scanning microscopy findings.

Multiple cartilaginous exostosis was diagnosed in a six-month-old Golden Retriever cross-bred male with a history of forelimb lameness and isolated, but very painful, acute episodes. Physical examination revealed a right forelimb lameness with a firm, painful palpable mass on the cranial aspect of the forearm. The radiological examination showed the presence of bony masses at the humerus and radius as well as several masses in the ribs and spinous processes of the thoracic vertebrae. Based on the history and radiographic findings, multiple cartilaginous exostosis was diagnosed. Treatment with non-steroidal anti-inflammatory drugs was commenced for two weeks without any effect. Due to the lack of a response to the treatment as well as to the progressive physical deterioration of the animal, the owners requested euthanasia of the dog. Histology of the different exostoses demonstrated the presence of a hyaline cartilage cup surrounding a central area, formed mainly by bone and cartilage trabecullae. Signs of malignancy were not observed. Back-scattered scanning electron microscopy (BEI-SEM) study revealed well ordered and progressively calcified cartilage trabecullae present underneath the non-calcified cartilage cap. At a greater depth, those cartilage trabecullae became osteochondral trabecullae, and the innermost were formed exclusively by woven and lamellar bone. The histological and back-scattered electron scanning microscopy results conclude that it was a well-arranged normal endochondral ossification process that followed a centripetal pattern inside the bony mass, confirming the diagnoses of multiple cartilaginous exostoses.

Animals↗

[A case of pneumothorax in a patient with costal exostosis].

A 21-year-old male was admitted to our hospital complaining of chest pain. He had undergone operations on multiple exostoses of his lower extremities when he was thirteen and fifteen years old. Family history revealed multiple exostoses in his mother and one of his cousins. Chest roentgenograms showed right pneumothorax and a mass arising from the seventh rib in the right lower lung filed. Chest CT revealed that the mass was located in thorax but outside the lung. These findings suggested that the pneumothorax was secondary to the injury of the right lung caused by an exostosis arising from the rib. Upon operation, we found a laceration of the lower lobe and a hard mass the size of a pea protruding from the seventh rib. A small bony spicule was also found to be projecting from the sixth rib. The hard mass and the spicule were resected with a normal portion of the seventh and the sixth ribs. The pathological findings of these bony lesion proved to be consistent with exostosis. The patient's postoperative course was uneventful. This case of pneumothorax caused by an exostosis lacerating the lung is rare.

Adult↗

[The treatment of insertion desmopathy in the metatarsus of horses].

Metacarpal or metatarsal exostoses were diagnosed in 112 horses used for sport purposes between January 1976 to December 1987. Fourteen of these patients were treated surgically by subperiosteal removal of the exostosis. All animals which could be followed up had returned to their original use. The average time of use after discharge from the clinic was 38.4 months. Surgery was successful in completely removing the exostoses in 58.3% of these horses. The indications for anaesthesia and resection of the ulnar nerve are discussed.

Animals↗

The Langer-Giedion syndrome: report of a 22-year old woman.

A 22-year-old woman with the Langer-Giedion syndrome and delayed puberty is presented. Pertinent features include a bulbous nose, sparse hair, protruding ears, multiple cartilaginous exostoses, cone-shaped phalangeal epiphyses, short stature, microcephaly, and mental retardation. She is the oldest patient thus far described with this condition, and is compared to the ten previously published cases. The clinical course of patients with the Langer-Giedion syndrome and the possibility of malignant change in the exostoses have not been established.

Adult↗

[Chondrosarcoma of the bone. Differential pre- and postoperative diagnosis using magnetic resonance].

Twelve patients were studied by means of Magnetic Resonance Imaging (MRI) in order to demonstrate either loco-regional recurrence of central chondrosarcomas or degenerative evolutions of exostoses. MRI findings were compared with plain film, scintigraphy, and Computed Tomography. MRI showed loco-regional recurrences by demonstrating their site, extent, and relationship with adjacent structures. In showing the degenerative evolution of exostoses MRI--confirmed at surgery--was superior to plain film in 3 cases out of 7, and to Computed Tomography in 2 cases. The authors discuss MRI findings: chondrosarcomas have low-intensity signal in T1-weighted sequences and high-intensity signal in T2-weighted. Thanks to its high contrast resolution MRI always allowed the detection of the chondrosarcoma. Nevertheless, MRI did not allow the tumor grading--which is due either to a difficult evaluation of the morphology of neoplastic calcifications, or to non-specific-intensity signal.

Adolescent↗

[Langer-Giedion syndrome and deletion in the long arm of chromosome 8].

Del(8) (q24.11-q24.13) were detected in 3 patients with typical Langer-Giedion syndrome (LGS) and studied by high-resolution methods. Analysis of the literature strongly suggests the chromosomal ethiology of the LGS, because in all patients examined in detail a deletion of the segment 8(q24.11-q24.13) was revealed, which is critical for the LGS. Interrelationships between the LGS and two monogenic conditions-tricho-rhino-phalangeal syndrome type I and multiple exostoses are discussed. The possible role of c-myc oncogene in exostoses' (including those in LGS) origin is anticipated.

Adolescent↗

[Metachondromatosis. Report of a family with 4 cases].

Metachondromatosis is a hereditary dominant condition, which was differentiated from multiple hereditary cartilaginous exostoses by Maroteaux in 1971. We observed a family with 4 patients in 3 generations. The condition manifested in early childhood, showed a spontaneous regression after cessation of growth, and could be diagnosed with certainty by radiological signs. We found multiple tiny periarticular calcifications, small exostoses especially on the short tubular bones, and enchondromatous bone changes. The vertebral column takes part in the bone dysplasia. In addition, our patients show deformities of nails and teeth.

Adolescent↗

Peroneal paralysis due to exostosis of the fibula. Report of 2 cases.

Exostoses in certain situations such as the armpit or the popliteal region, can cause vascular or neurological compression syndromes. Exostoses of the neck of the fibula can in this way produce late paralysis of the peroneal nerve. Two such cases are presented in young patients, in whom the neurological damage was produced by increased growth distally of the neoplasm.

Child↗

Ext-mutation analysis in Italian sporadic and hereditary osteochondromas.

Osteochondromas represent the largest group of benign tumors of bone. Multiple osteochondromatosis or hereditary multiple exostoses (EXT) is an autosomal dominant inherited disorder characterized by the presence of multiple benign cartilage-capped exostoses. EXT is genetically heterogeneous with at least 3 chromosomal loci: EXT1 (8q24.1), EXT2 (11p11-p13), and EXT3 (19p). In <5% of EXT patients, the inactivation of both copies of EXT alleles (LOH) is associated with malignant transformation. We have analyzed the EXT1 and EXT2 genes in 9 unrelated EXT families and in a patient with a sporadic osteochondroma, all originating from Italy. Four families show an EXT1 mutation, consisting of a small deletion in 3 of them and a small insertion in the 4th. All these mutations lead to premature termination of translation and thus a truncated EXT1 protein. Three families presented EXT2 mutations consisting of nucleotide substitutions leading to alterations of the third intron splice-site, to an amino acid substitution and to a nonsense mutation. All these mutations cosegregate with the disease phenotype. The sporadic osteochondroma patient carried a novel missense mutation in exon 11 of EXT2 gene, leading to an amino acid substitution. Seven of these mutations have never been described before. EXT2 missense mutations were also confirmed by amino acids conservation between human and mouse and by analysis of a healthy control population. In conclusion, our study provide further evidence that loss of function of the EXT1 or EXT2 gene is the main cause of EXT supporting the putative tumor-suppressor function of these genes.

Adolescent↗

Chronic intoxication by ethane-1-hydroxy-1,1-diphosphonate (EHDP) in a child with myositis ossificans progressiva.

A child with myositis ossificans progressiva was treated for 8 years with ethane-1-hydroxy-1,1-diphosphonate (EHDP) 30-40 mg/kg per day. Latterly he complained of severe, progressive bone and joint pain which made standing and walking almost impossible. A radiographic skeletal survey showed diffuse ricket-like lesions. Withdrawal of EHDP therapy produced substantial improvement in his general condition as well as in the radiographic appearance of the bones. Multiple exostoses were observed in this case and, particularly those around the knees, presented a peculiar morphology. This supports the theory that exostoses originate from a defect of metaphyseal modelling.

Adolescent↗

Popliteal pseudoaneurysm as a complication of an adjacent osteochondroma.

A 19-year-old man presented to our institution with a 4-month history of a pulsatile mass in the left popliteal fossa. Evaluation including plain x-ray films, MRI, and arteriography revealed a pseudoaneurysm associated with an underlying exostosis of the distal femur. The pseudoaneurysm was repaired with a saphenous vein patch and the exostosis was excised. This case is reported in conjunction with an extensive review of the literature, which yielded only 25 similar cases reported in the English language since 1953. The majority of cases involved young men (20/26), whose ages ranged from 9 to 45 years (mean 20 years). Fifteen of the 26 cases involved isolated exostoses, and in less than half (12/26), antecedent trauma was identified as a cause of the pseudoaneurysm. The origin of exostoses and their relationship to popliteal pseudoaneurysms are discussed. Repair of the pseudoaneurysm and excision of the involved exostosis are recommended.

Adult↗

EXT1 regulates chondrocyte proliferation and differentiation during endochondral bone development.

Multiple Hereditary Exostoses (MHE) is an autosomal dominant skeletal disorder most frequently caused by mutations in the EXT1 gene. MHE affects proper development of endochondral bones, such that all affected individuals present with exostoses adjacent to the growth plate of long bones, while some individuals exhibit additional bone deformities. EXT1 functions as a heparan sulfate (HS) co-polymerase, and when defective causes improper elongation of glycosaminoglycan side chains on core proteins of HS proteoglycans. Although analysis of heterozygous EXT1-deficient mice has failed to reveal any significant gross morphological variations in skeletal development, significant alterations in molecular signaling occur in the developing long bones. Our results indicate that defects in EXT1 and the resulting reduction in HS lead to enhanced Indian Hedgehog diffusion causing an increase in chondrocyte proliferation and delayed hypertrophic differentiation.

Animals↗

Peroneal nerve compression resulting from fibular head osteophyte-like lesions.

BACKGROUND: The anatomical relationship of the fibular head with the fibular nerve is a critical point in regard to injuries of peripheral nerves in the lower extremities. In this location, the peroneal nerve may be injured due to several mechanisms, and osteophyte-like lesions can be considered as a differential diagnosis. METHODS: The suitable literature concerning this association is reviewed and a case is presented. A 15-year-old adolescent boy presented with right peroneal nerve palsy on admission. The radiological examinations (computed tomography and magnetic resonance imaging) demonstrated an osteophytic lesion in the head of the right fibula. The patient underwent surgical decompression of the nerve and resection of the lesion. Postoperatively, there was a complete recovery of the deficits. CONCLUSIONS: The association of osteophyte-like bone changes and peroneal nerve palsy is rare. The differential diagnoses of these lesions include cartilaginous exostoses and osteochondromas, which may be related to hereditary multiple exostoses syndrome. The timing of the treatment plays an important role in the neurological recovery.

Adolescent↗

Osteocartilaginous lesions of the digits in children: an experience with 10 cases.

Osteocartilaginous lesions, which are considered to be one of the most common neoplasms of bone, are seldom found in the hand. These are distinct from subungual exostoses or turret exostoses. When present in the hand in children, these lesions may limit function, cause cosmetic deformity, alter the growth of a digit, and pose a problem in diagnosis. Experience with these osteocartilaginous lesions in 10 children, (nine boys and one girl) is reviewed. Six patients had some degree of deviation or early rotation of the involved digit secondary to abnormal bone growth. There was no definite history of antecedent trauma; however, most parents assumed this to be a causative factor. Patients were treated by excision of the lesion and joint contouring when necessary. Follow-up ranged from 1.5 to 13 years, and there was good functional restoration, minimal growth disturbance, and no recurrence in any patient.

Adolescent↗

Classification of bone tumors.

The classification of bone tumors relies on the cytologic features and products of tumor cells. This classification is reproducible and accepted by pathologists, oncologic surgeons and oncologists. Chondrogenic tumors are the second largest group of bone tumors. Their histologic pattern suggests a relationship to hyaline cartilage. Exostoses, or osteochondromas, represent about 1/3 of chondrogenic lesions. Chondromas are hyaline cartilage tumors which can be found centrally or subperiosteally; they may contain some calcifications and/or ossifications. Chondroblastomas are tumors whose cells produce, at least focally, a matrix similar to hyaline cartilage. Histology of chondromyxoid fibromas shows large or small areas where proliferating cells produce a matrix resembling the hyaline cartilage. Chondosarcomas are tumors whose malignant cells produce a cartilaginous matrix. Most of them occur in previously normal bones; they are classified as conventional or primary chondrosarcomas. Secondary chondrosarcomas result from the malignant transformation of a benign cartilaginous lesion less commonly enchondromas and most commonly osteocartilaginous exostoses, or osteochondromas. Less common variants include dedifferentiated, mesenchymal and clear cell chondrosarcomas. Osteogenic tumors are the third largest group of bone tumors, with osteosarcomas being the most frequent type. The most important criterion for a tumor to be considered an osteosarcoma is that the malignant tumor cells must produce a recognizable osteoid matrix, at least focally. Osteosarcomas are divided into three groups: osteoblastic, chondroblastic and fibroblastic, according to the dominant histologic feature. Osteosarcomas can be multifocal, synchronous or metachronous; they are also classified by the histologic grade of malignancy. Pathologically low grade lesions, which are clinically indolent, are generally known as low grade central and parosteal osteosarcomas.

Bone Neoplasms↗

Plasminogen activators and their inhibitor in bone tumors and tumor-like damages.

Expression of urokinase- and tissue-type plasminogen activators and their inhibitor PAI-1 in the cytosolic fraction of 20 osteosarcomas, 20 chondrosarcomas, 13 giant-cell bone tumors, 5 Ewing's sarcomas, and 7 osteochondral exostoses was studied by enzyme immunoassay. The content of urokinase-type plasminogen activator increased, while the concentration of tissue-type plasminogen activator decreased in bone tumors of various histological compositions compared to osteochondral exostoses. A positive correlation was found between PAI-1 content and the volume of osteo- and chondrosarcomas. Expression of urokinase-type plasminogen activator increased in patients with primary osteosarcomas characterized by early generalization of the pathological process.

Adolescent↗

Komrower Lecture. Congenital disorders of glycosylation (CDG): it's all in it!

Congenital disorders of glycosylation (CDGs) are due to defects in the synthesis of the glycan moiety of glycoproteins or other glycoconjugates. This review is devoted mainly to the clinical aspects of protein glycosylation defects. There are two main types of protein glycosylation: N-glycosylation and O-glycosylation. N-glycosylation generally consists of an assembly pathway (in cytosol and endoplasmic reticulum) and a processing pathway (in endoplasmic reticulum and Golgi). O-glycosylation lacks a processing pathway but is otherwise more complex. Sixteen disease-causing defects are known in protein glycosylation: 12 in N-glycosylation and four in O-glycosylation. The N-glycosylation defects comprise eight assembly defects (CDG-I) designated CDG-Ia to CDG-Ih, and four processing defects (CDG-II) designated CDG-IIa to CDG-IId. By far the most frequent is CDG-Ia (phosphomannomutase-2 deficiency). It affects the nervous system and many other organs. Its clinical expression varies from extremely severe to very mild (and thus probably underdiagnosed). The most interesting disease in this group is CDG-Ib (phosphomannose isomerase deficiency) because it is so far the only efficiently treatable CDG (mannose treatment). It has a hepatic-intestinal presentation. The O-glycosylation defects comprise two O-xylosylglycan defects (a progeroid variant of Ehlers-Danlos syndrome and the multiple exostoses syndrome) and two O-mannosylglycan defects (Walker-Warburg syndrome and muscle-eye-brain disease). All known CDGs have a recessive inheritance except for multiple exostoses syndrome, which is dominantly inherited. There is a rapidly growing group of putative CDGs with a large spectrum of clinical presentations (CDG-x). Serum transferrin iso-electrofocusing remains the cornerstone of the screening for N-glycosylation defects associated with sialic acid deficiency. Abnormal patterns can be grouped in to type 1 and type 2. However, a normal pattern does not exclude these defects. Screening for the other CDGs is much more difficult, particularly when the defect is organ- or system-restricted. The latter group promises to become an important new chapter in CDG. It is concluded that CDGs will eventually cover the whole clinical spectrum of paediatric and adult disease manifestations.

Bacterial Proteins↗

Tout-velu is a Drosophila homologue of the putative tumour suppressor EXT-1 and is needed for Hh diffusion.

Hedgehog (Hh) proteins act through both short-range and long-range signalling to pattern tissues during invertebrate and vertebrate development. The mechanisms allowing Hedgehog to diffuse over a long distance and to exert its long-range effects are not understood. Here we identify a new Drosophila gene, named tout-velu, that is required for diffusion of Hedgehog. Characterization of tout-velu shows that it encodes an integral membrane protein that belongs to the EXT gene family. Members of this family are involved in the human multiple exostoses syndrome, which affects bone morphogenesis. Our results, together with the previous characterization of the role of Indian Hedgehog in bone morphogenesis, lead us to propose that the multiple exostoses syndrome is associated with abnormal diffusion of Hedgehog proteins. These results show the existence of a new conserved mechanism required for diffusion of Hedgehog.

Amino Acid Sequence↗