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J Dubousset

Publications and source records attributed to J Dubousset.

At least 55 records · Page 3Linked to original sources
PubMed1996

Melatonin. A possible role in pathogenesis of adolescent idiopathic scoliosis.

STUDY DESIGN: The serum melatonin levels during 24-hour periods were compared between patients with idiopathic and age-matched normal control subjects. OBJECTIVE: To find if the melatonin deficiency may have some role for progression or etiology of idiopathic scoliosis in humans. SUMMARY OF BACKGROUND DATA: Experimentally induced scoliosis in chicken by pinealectomy can be attributed to the defect in melatonin metabolism. METHOD: Blood samples were correlated every 3 hours during 24-hour periods, and serum melatonin levels were measured and statistically analyzed. RESULTS: The level of melatonin, integrated concentration through 24 hours and night time (0:00 am-6:00 am), in the patients who had progressive curve (more than 10 degrees of progression in the previous 12 months) was significantly lower than the level in the patients who had a stable curve (less than 10 degrees of progression in the previous 12 months) or in the control subjects (P < 0.05). CONCLUSION: The study suggests that normal melatonin synthesis or metabolism may have crucial role in regulating normal spine growth. The level of melatonin appears to be a useful predictor for progression of spine curvature in idiopathic scoliosis.

Adolescent↗
PubMed1996

The congenital dislocated spine.

STUDY DESIGN: The congenital dislocated spine has been defined as the potentially most serious form of congenital kyphosis with an abrupt single-level displacement of the spinal canal. A retrospective chart review was conducted on 19 patients with this deformity. OBJECTIVES: To delineate the clinical and radiologic characteristics of this entity, and to analyze the outcome after treatment. SUMMARY OF BACKGROUND DATA: An anterior failure of formation was the basic feature. Kyphosis was variable. Vertebral displacement in the frontal plane was present in seven patients, and sagittal displacement was constant. Mechanical instability was seen in 17 patients. Neurologic impairment was identified in 12 patients, and congenital paraplegia was seen in eight patients. An acute paraplegia occurred after minor trauma in one patient. METHODS: Seventeen patients were treated surgically. Thirteen patients underwent complete circumferential stabilization through anterior strut grafting and posterior fusion without instrumentation, usually before age 3 years. Neurosurgical decompression was done in four patients. RESULTS: The average follow-up period was 8 years, 6 months. Nonunion of the posterior fusion mass was detected and successfully treated in five patients. A solid fusion seemed to be obtained in all patients at last follow-up evaluation. The neurologic status after neurosurgical decompression remained unchanged in three patients and was improved temporarily in one patient. CONCLUSIONS: Avoidance of neurologic morbidity requires early diagnosis and stabilization. The authors recommend early anterior strut grafting and posterior fusion. Exploration of the posterior fusion mass should be done systematically.

Adolescent↗
PubMed1996

[Extra osseous tumors of the spine in children and adolescents. Spinal complications].

PURPOSE OF THE STUDY: The delay in diagnosis of spinal tumors is not rare. The chief complaint may include pain, walking disability, and spinal or limb deformities. The purpose of our study is to analyze the spinal deformities associated with non osseous intraspinal tumors, to assess the complications of treatment, and to set out a preventive protocol. MATERIALS: We reviewed retrospectively 40 consecutive cases of non osseous intraspinal tumors treated between 1972 and 1991. There were 32 intradural, 2 extradural, and 6 intra and extradural combined tumors. At the first consultation, the age ranged between 4 months and 15 years, and only 16 patients showed neurologic deficit. Spinal deformity existed in 9 patients, 7 of which had no neurologic deficit. All the tumors were treated surgically. Laminectomy was done in 28 cases, and osteoplastic laminotomy in 12 cases. The number of levels included in the laminectomy ranged from 3 to 18. Bilateral arthrectomy at least at one level was undertaken in 15 cases. A postoperative brace was worn in all cases for an average period of 4 months. An adjuvant radiotherapy was undertaken in 12 cases for an incomplete resection. METHODS: The incidence and pattern of spinal deformity was assessed before tumor treatment and ultimately after laminectomy or osteoplastic laminotomy (or laminoplasty). RESULTS: Among the 9 cases with preexisting spinal deformity, the curve magnitude increased after laminectomy in 4. A kyphotic, kyphosoliotic or scoliotic deformity developed in 18 cases after surgery for tumor resection. Among these 18 patients, only one had had an adequate osteoplastic laminotomy. The treatment of spinal deformities was surgical in 12 cases, and done by either posterior or anterior and posterior combined arthrodesis. DISCUSSION: Spinal deformity may be the main complaint of a patient who has intraspinal tumor. Prevention of postlaminectomy spinal deformity is mandatory, and could be done by osteoplastic laminotomy and the use of a brace during a minimum period of 4 to 6 months after surgery. CONCLUSION: Diagnosis of intraspinal tumors in children and adolescents should be done early, and laminoarthrectomy should be replaced by osteoplastic laminotomy.

Adolescent↗
PubMed1996

[Reconstruction of the long bones of the legs in children via free vascularized transplant of the fibula after resection for sarcoma].

Nineteen children were operated on between 1985 and 1994. All the patients presented a sarcoma of long bones: osteosarcoma: 12 and Ewing's sarcoma: 7. They were operated on: resection and reconstruction of the long bones with a free vascularised fibula. Pre and post-operative chemotherapy was used. The average follow-up was 3 years (between 10 years and 1 year). The mean bone defect was 20 cm (between 32 and 11 cm). Boys were more frequently encountered [12]. Average age was 9.5 years. The pathological bone was: femur: 14, tibia: 4, humerus 1. The approach needs usually two incisions for femoral bone: the internal incision allows us to prepare the recipient vessels: deep femoral vessels in 11 cases. In 18 cases, union occurred in less than 14 months. One case of pseudarthrosis occurred. Immediate follow-up was simple in 17 cases. Infection was observed in 2 cases. Secondly, the most frequent complications were: fracture of the fibula: 6 cases, vicious cal: 2 cases; delayed union: 6 cases; stiffness: 2 cases. One patient died later from pulmonary metastasis. Solid osteosynthesis of the member and of the free vascularised fibula permit to shorten these delays. Success depends on two criteria: the graft thickening of the fibula and union of the fibula at both ends. The micro vascular anastomoses must be excellent. Twelve children had bone union with only one operation. In the 6 cases of delayed union, secondary bone grafts give consolidation. The comparison of this technique with standard treatment showed an evident superiority of the free vascularised fibula transplant in extensive defects of bone. The fibula is a life bone which permits rapid union with a short hospitalization, a quick recovery and an early return to school. Free vascularised fibula permit to ameliorate the quality of survival.

Bone Neoplasms↗
PubMed1995

CDH: preliminary report on a new anterior spinal instrumentation.

CDH (Cotrel-Dubousset-Hopf) instrumentation was developed with the aim of improving stability in ventral operation procedure and facilitating treatment of all anterior spinal diseases. The implantation of anterior plates and drawers, the use of a double-rod fixation within the implant in nonparallel directions, which provide an automatic locking mechanism against displacement, the prevention of dislocation of the cancellous bone srews, and the crosslink principle are its main characteristics. The device can be applied to the spine in accordance with its three-dimensional anatomy by any kind of force (distraction, compression, and rotation). Additional posterior instrumentation and postoperative external support are unnecessary in most cases because of improved stability. No reoperation was necessary following the mono- and multisegmental application of this method in 60 patients (28 with scoliosis, 12 with spondylodiscitis, 8 with primary tumors or isolated metastasis, 6 with fractures, 3 with failed back syndrome, 1 with kyphotic deformity, 1 with spondylolisthesis on two levels, and 1 with loss of correction after the dislocation of another posterior spinal instrumentation). Average blood loss was 950 ml; the average operating time was 3 h. In all, 16 monosegmental and 44 multisegmental procedures were carried out. In 25 patients, in particular those with paralytic scoliosis, a double-stage anterior and posterior spondylodesis was done.

Adolescent↗
PubMed1995

Role of melatonin deficiency in the development of scoliosis in pinealectomised chickens.

We studied the possible role of melatonin deficiency in experimentally-induced scoliosis. A total of 90 chickens underwent pinealectomy on the third day after hatching: 30 were treated with serotonin, 30 with melatonin and 30 received no therapy (control group). Scoliosis developed in all the control group, in 22 of the serotonin group, and in only 6 of the melatonin group. The six melatonin-treated chickens with scoliosis had less severe spinal deformities than those in the serotonin-treated group. There were lower blood melatonin concentrations in chickens with scoliosis than in those without. Our findings suggest that melatonin deficiency contributes to the aetiology of this experimental scoliosis, probably by interfering with the normally symmetrical growth of the proprioceptive system involving the paraspinal muscles and the spine.

Animals↗
PubMed1995

[Cervical spondylolysis in children. Apropos of 4 cases. Review of the literature].

PURPOSE OF THE STUDY: A clinical and radiological study of four cases of spondylolysis in children. Literature review shows the congenital origin of the disorder and how it is to be treated. MATERIAL AND METHODS: We report on four children with cervical spondylolysis. One of the children presented a two-level spondylolysis C5C6. One case was totally asymptomatic and was hazardly discovered. Standard radiographs were used for diagnosis. Conservative treatment was administered in all cases and all patients were immobilized for a few days. DISCUSSION: It has been clearly established that cervical spondylolysis is a congenital disorder often associated with other anomalies: spina bifida, dysplasia of the posterior articular processes. In the child, cervical spondylolysis is only discovered in fifty per cent of Post traumatic cases. The most frequent finding is at C6. A diagnosis can be made based on the radiographs and the CT scan. MRI will only be indicated in spondylolisthesis in order to analyze the disc statement and the degree of canal narrowing. When possible conservative treatment should be adopted. Arthrodesis is reserved for unstable and painful lesions. CONCLUSION: Cervical spondylolysis in the child is a rare congenital disorder. It must be distinguished from the congenital absence of a pedicle and from a pedicle or isthmic fracture. It is a lesion which is normally discovered once the patient has turned adult and is very well long term tolerated.

Adolescent↗
PubMed1995

[Study of the reactivity of giant cell tumors of bones to different lectins].

The authors have examined 18 cases of giant cell bone tumours using various lectins. Type I stromal cells resembling fibroblasts and participating in the construction of matrix were Con A positive. The intensity of Con A binding and the number of positive cells increased with increasing stage. The nature and intensity of PNA-lectin binding in giant cells, after digestion with neuraminidase, varied according to the stage. While in Group I giant cells, 30 % of cells were negative and, in the great majority of cells, the reaction was limited to a clearly defined segment of the membrane, in Group III tumours, the proportion of negative cells was approximately 1 % and a diffuse and very intense intracytoplasmic reaction was observed in 60 % of the positive cells. According to the authors, the histochemical study of lectins could help classify giant cell tumours.

Adolescent↗
PubMed1994

Posterior spinal fusion in neuromuscular scoliosis using a tibial strut graft. Results of a long-term follow-up.

STUDY DESIGN: Risks and benefits of using a tibial graft for posterior spinal fusion in neuromuscular scoliosis were evaluated in a long-term follow-up study. A consecutive series of 72 patients underwent posterior spinal fusion for neuromuscular scoliosis. OBJECTIVES: Radiologic outcome was assessed to evaluate the quality of the spinal fusion. Patients were followed serially to detect donor site complications. Mean follow-up was 17 years and 8 months (minimum: 6 years, 6 months). SUMMARY OF BACKGROUND DATA: Mean age of the patients at the time of surgery was 15 years. Progression of the curvature was minimal at last follow-up (mean progression at last follow-up: lumbar curve, 4.5 degrees; thoracic curve, 5.3 degrees). Concerning donor site complications, four patients had a leg length discrepancy of less than 2 cm at last follow-up. This complication was related to tibial overgrowth at the donor site. METHODS: Solid fusion was defined in this long-term study as the absence of modification of the radiologic aspect at last follow-up in addition to the presence of a massive contagious trabecular fusion mass. RESULTS: The fusion appeared to be solid in all patients. No obvious pseudarthrosis could be documented. The constant successful outcome differs significantly from spinal fusion that uses bank bone. The absence of stress fracture was correlated to the low level of constraint in this essentially nonambulatory population. CONCLUSION: This experience indicates that the tibial graft deserves consideration in posterior spinal fusion for neuromuscular scoliosis.

Adolescent↗
PubMed1994

Combined anterior and posterior convex epiphysiodesis for progressive congenital scoliosis in children aged < or = 5 years.

Six patients aged < or = 5 years with congenital scoliosis due to vertebral malformation were treated by anterior and posterior epiphysiodesis of the convexity. In all cases the pattern of deformity was a kyphoscoliosis. The average age at operation was 3 years 6 months, average follow-up was 4 years 6 months, and average preoperative angles were 42 degrees in the frontal and 36 degrees in the sagittal plane. The fusion included the malformative zone and the superior and inferior adjacent vertebrae. Two patients had a fusion effect, three patients had a true epiphysiodesis effect, and one patient had a postoperative progression of the deformity. Epiphysiodesis of the convexity is a treatment proper for the growing period, allowing the child either to reach skeletal maturity without needing further treatment or to achieve an adequate torso height to finish the treatment with a classical vertebral arthrodesis.

Child, Preschool↗
PubMed1994

[Ischio-vertebral dysplasia (a dangerous syndrome for the spinal cord)].

PURPOSE OF STUDY: A previously unreported condition is defined, diagnostic features identified, and clinical course and treatment modalities presented. MATERIAL AND METHODS: This is a retrospective study of 11 patients with ischio-vertebral dysplasia (IVD), accomplished by record and radiographic review. RESULTS: 11 patients were included in the study group, age at presentation from 1 day to 33 yrs. Follow-up ranged from 5-30 yrs. Involvement of 3 successive generations (grandmother, mother and daughter) with similar findings was present in 1 family. Common features of IVD include: peculiar facies incomplete ossification of the ischial ramus, and a dysplasic scoliosis with a significant kyphotic element, constituting a rotatory dislocation. 2 patients followed from birth demonstrated the natural history of the condition, beginning without spinal deformity, and progressing to significant deformity. The spinal deformity was manageable surgically. The scoliosis ranged from 10 degrees to 235 degrees, and the kyphosis from 0 degrees to 200 degrees (the 10 and 0 being at day 1 of age). 6 patients incurred neurological sequelae, either spontaneously or associated with surgical treatment. 2 patients died, 1 due to cardiopulmonary failure at age 33; the 2nd was an infant with severe neurologic and cardiopulmonary complications due to the spinal deformity. Multiple surgical approaches to the problems were employed. Analysis of results permitted formulation of a logical and successful approach to the problem. Pre-op mean kyphosis = 112 degrees, post-op at maximum follow-up = 67 degrees. Deformity stabilization and neurologic normalcy was produced in every patient operated but 1. DISCUSSION: The characteristics of the syndrome are clear, as is the progressive nature of the deformity. The very high risk of neurologic involvement is emphasized. Before age 10, circumferencial fusion prevents progression and neurologic deterioration. Older patients require gradual correction by skeletal traction, followed by anterior concave strut stabilization and posterior fusion (with or without instrumentation). Extreme care is necessary for protection of the particularly vulnerable neurologic structures. Early stabilization and correction is recommended for prevention of the deterioration of cardiopulmonary function.

Abnormalities, Multiple↗
PubMed1993

An experimental study in chickens for the pathogenesis of idiopathic scoliosis.

Experimentally induced scoliosis was investigated in pinealectomized chickens using pathologic and neurophysiologic means. A total of 90 chickens were tested; 30 served as a normal control, 30 received an autografted pineal body in the intramuscular tissue of the trunk, and 30 underwent pinealectomy without autograft. Scoliosis developed in all pinealectomized chickens within 2 weeks, showing gradual progression during the next 5 or 6 weeks. At 3 months, the three-dimensional spinal deformity consisted of lateral curvature and vertebral body rotation, resulting in a prominent lordoscoliosis at the thoracic level. In contrast, scoliosis developed in only 10% of the autografted chickens. Histologic examination revealed no pathologic change in the brain in either the pinealectomized scoliosis group or in the autografted nonscoliosis group. Cortical potentials in the scoliosis group were delayed, thus suggesting conduction disturbance rostral to the brain stem. Although the relationship between the cause and effect is uncertain, these findings implicate neurotransmitters or neurohormonal systems in the pineal body as a major contributing factor in this type of experimental scoliosis.

Animals↗
PubMed1993

Direct Ethibloc injection in benign bone cysts: preliminary report on four patients.

Benign bone cysts often require treatment in order to prevent pathological fracture. We report preliminary experience with percutaneous injection of Ethibloc in four children (8-15 years old) presenting with benign bone cysts: two were aneurysmal bone cysts, two were unicameral bone cysts. All the patients were followed up for 12-18 months. Healing was satisfactory in all cases and no complications occurred.

Adolescent↗
PubMed1993

Fibrodysplasia ossificans progressiva and synovial chondromatosis.

Two cases of an unusual association-fibrodysplasia ossificans progressiva and synovial chondromatosis-in non-related children are presented. This association does not seem coincidental and raises several questions about the pathogenesis. A genetic hypothesis related to G proteins is proposed. This is supported by the fact that such abnormalities have been demonstrated in pseudohypoparathyroidism and fibrous dysplasia; these diseases can also be associated with fibrodysplasia ossificans progressiva.

Adolescent↗
PubMed1993

A biomechanical analysis of short segment spinal fixation using a three-dimensional geometric and mechanical model.

Vertebral stabilization using spinal fixation devices is a widely used technique. A three-dimensional geometric and mechanical finite element model has been used as a simulation tool for the evaluation of the mechanical behavior of spinal devices. The geometry of lumbar vertebrae was parameterized, which allows the construction of the geometric model for a given lumbar segment from the digitization of two roentgenographs. This procedure was used to construct a finite element model for a three-vertebra segment with simulation of fractures in the middle vertebra, and with simulation of a restoration using an osteosynthesis device, implemented in a frame fashion with four screws and two rods linked by two transverse rods, and/or an anterior bone graft. Compression force and torsion moment were considered, and different cases were investigated, by varying the severity of the fracture, the geometric characteristics of the device, and the mechanical characteristics of the material joining the two intact vertebral bodies. Results were analyzed considering the mobility of the vertebral segment, which indicates the ability of the restoration system to stabilize the vertebral segment, and considering the forces and moments distribution in the device, which gives information on part of the forces that pass through the device in each situation. Results show that maximum values of forces and moments in the device are more important in compression than in torsion. Adding an anterior bone graft has an effect mainly for compression, whereas in torsion its effect is negligible. For a rigid fixation device, no significant difference was found between different fracture models, indicating that the posterior arch does not play an important role for an instrumented segment. For compression, a rigid posterior wall, or the presence of a bone graft, reduces greatly the mobility of the instrumented segment. For torsion, suppressing the two transverse rods in the device greatly increases the mobility of the instrumented segment. Using a finite element model of a lumbar vertebral segment appears to be an interesting tool to analyze the behavior of an instrumented spine and to compare between different stabilization systems.

Biomechanical Phenomena↗
PubMed1992

Does malignant small round cell tumor of the thoracopulmonary region (Askin tumor) constitute a clinicopathologic entity? An analysis of 30 cases with immunohistochemical and electron-microscopic support treated at the Institute Gustave Roussy.

The morphology and clinical outcome of 30 patients with malignant small round cell tumors located in the thoracopulmonary region (Askin tumor) are reported. Histologically, all tumors had similar patterns, with small round-to-oval cells and a lobulated stroma. Immunohistochemical analysis always resulted in positive staining for one or several neural markers. No significant differences were found compared with the immunomarkers in 26 typical Ewing's sarcomas located outside the thoracic wall. In three specimens, electron microscopy confirmed the presence of membrane-bound neurosecretory granules. It was confirmed that there is a remarkable similarity among all malignant small round cell tumors, including Askin tumor and Ewing's sarcoma. Overall survival was poor with a 2-year rate of 38% and a 6-year rate of 14%.

Adolescent↗
PubMed1992

Characterization of bone forming cells in posttraumatic myositis ossificans by lectins.

Lectins were used to characterize bone forming cells in posttraumatic myositis ossificans. The lectins applied were as follows: Arachis hypogaea (PNA): specific for beta-D-galactose (1,3)N-acetyl-D-galactosamine (Gal-1,3 GalNac), Canavalia ensiformis (Con A): specific for alpha-D-glucose (D-Glc) and alpha-D-mannose (D-Man) and Wheat germ (WGA): specific for N-acetyl(1,4)D-glucosamine (Glc-NaC) and neuraminic acid. The development of myositis ossificans was characterized by the appearance of a WGA binding cell population. The lectin-binding sites appeared as a cluster in the supranuclear cytoplasm, corresponding to the Golgi-complex. However, the WGA lectin-binding sites disappeared in the mature form of myositis ossificans. We assume that these lectin binding cells may be the bone marrow derived precursors of myofibroblast-like cells which are responsible for bone formation within the damaged muscle.

Adolescent↗