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J Prévot

Publications and source records attributed to J Prévot.

At least 19 recordsLinked to original sources

[Reduction of the period of treatment for leg lengthening. Technique and advantages].

PURPOSE OF THE STUDY: We assessed an adaptation of the Ilizarov method aimed at a considerable reduction in the period of treatment for leg lengthening in order to limit complications related to the duration of the external fixation. This technique associates multiple segment lengthening, automatic high-frequency lengthening, and stimulation of bone regeneration by extemporaneous compression at the end of traction. MATERIAL AND METHODS: We analyzed 78 cases of automatic fémur lengthening in 40 patients and simultaneous fémur and tibia lengthening in 38 patients. There were 51 men and 27 women, mean age 13.2 years (6 - 43 years). Mean length deficiency was 4.3 cm for the fémur and 3.5 cm for the tibia. Femoral and/or tibial deformations were observed in 32 patients. Minimal follow-up was 1.5 years. The automatic traction device was composed of the conventional Ilizarov fixator and complementary elements. Different assemblies were used depending on the associated deformations allowing their progressive correction. For 17 patients, radioimmunoassay of thyrocalcitonin and parathormone was performed to compare the time courses. RESULTS: Mean femoral lengthening achieved was 49 mm (8.5 to 20%). Mean tibial lengthening was 42 mm (7.2 to 18.8%). The consolidation index was 18.1 to 21.3 days/cm for single-segment lengthenings and 11.5 days/cm (mean) for two-segment lengthenings (taking into account both the femoral and tibial gain in length). The ideal moment of compression was 5.6 N/cm(2). Acceleration of the bone repairing process was evidenced by activation of the osteotrop hormone system. According to the SOFCOT classification of complications (1990), 60 patients (76.9%) were in category I, 15 (19.3%) in category II, and 3 (3.8%) in category III. DISCUSSION: Improvement of lengthening procedures with external fixators remains an important issue. Treatment periods are often long with consolidation indices for the femur ranging from 39.6 d/cm to 45 d/cm, which can lead to many types of complications. Use of a high-frequency progressive lengthening procedure based on the Ilizarov method considerably reduces the rate of complications compared with progressive lengthening methods and has allowed achieving more satisfactory results in a shorter treatment period. CONCLUSION: Multiple-segment lengthening using an automatic lengthening procedure set at 1 mm per day in four times provides an important reduction in the treatment delays since distraction is performed more rapidly and fewer steps are needed. Automatic high-frequency lengthening with the Ilizarov method provides optimal conditions for tissue regeneration: Treatment periods are shorter and anatomic and functional outcome is very satisfactory. Stimulation by extemporaneous compression of the regeneration zone allows a significant reduction in the duration of consolidation. Shorter delays to consolidation help avoid device-related complications.

Adolescent↗

Treatment of sternocostal wall malformations of the child. A series of 210 surgical corrections since 1975.

Of 450 children examined for front chest wall malformations, 210 underwent a corrective operation: 190 funnel chests and 20 pigeon chests. A classification of the anatomic forms is presented which contains 6 groups: vertical cup-shaped (the most common), horizontal cup-shaped, vallecular, mixed, complex with sternal torsion or polymalformations. The operation has been programmed in 64% of the cases between 10 and 18 years, but 36% were operated under 6 years because of a severe functional disturbance. On the technical side, Ravitch's procedure is still used on young infants; for the other cases sternochondro-plasty is to be preferred. The fixation of the chest wall is realized with an original, light, solid elastic material taking little space, and easy to remove. This material is presented. The immediate results: 62% very good, 35% good and 3% mediocre, sometimes do present a pejorative evolution, so that after two years of follow-up we notice: 55% remained perfect, 35% very good, 10% moderate of which, 4% to be reoperated. This deterioration touches more particularly the older children operated between 16 and 18 years. Among the children between 3 and 6 years the results are usually very good and remain stable with growth.

Adolescent↗

Treatment of Langerhans-cell histiocytosis in children. Experience at the Children's Hospital of Nancy.

Forty children who had Langerhans-cell histiocytosis were followed for an average of six years (range, excluding patients who died of the disease, two to fifteen years). The patients were divided into two diagnostic groups: those who had localized disease (involving one bone or more only) and those who had multifocal disease (an osseous lesion and a soft-tissue mass, a skin rash, diabetes insipidus, or generalized disease). Methods of treatment included curettage, bone-grafting, chemotherapy, local or systemic corticosteroids, and radiotherapy. Nineteen of the thirty patients who had localized disease had a complete response to the therapy, four had a partial response, and seven had no response. Twenty-one of these thirty patients had not had a recurrence by the time of the latest follow-up examination; nine had a local recurrence within four years after the initial therapy but had no additional recurrences after treatment of the local recurrence. No recurrence occurred more than four years after the time that the initial diagnosis had been made. Five of the ten patients who had multifocal disease had a complete response to the therapy, two had a partial response, and three had no response. Six patients had a recurrence; four did not. Two patients died of the disease. As a result of this study, we recommend the avoidance of intensive measures of treatment, if possible, and we advise long-term follow-up of these patients.

Child↗

[Localizations of histiocytosis X in bone].

Histiocytosis X is still of unknown origin. Its clinical patterns are various and it is above all a bone disease of children, mostly boys. It is a tumoral condition basically benign but with a strong tendency toward dissemination and destruction. Its natural history is unpredictable. The authors have reviewed 37 cases after a 44 months mean follow-up for bringing up a better understanding of the role of orthopedic surgery. The diagnosis was always based on biopsies looking for at least two basic signs out of four possible ones. Scintigraphy was used to detect other locations. MRI was used to evaluate the effect of treatment. In single eosinophilic granuloma, curettage was associated with biopsy. Local injections of corticoids may help in spinal locations. In disseminated forms, surgical treatment should be little aggressive, limited to a biopsy of the most superficial lesion. These forms should be treated by radiotherapy corticotherapy and chemotherapy, as well as the aggressive lesions, the extensive ones, the threatening ones and those which are not accessible.

Adolescent↗

[Histomorphometry of bone regenerate in limb lenghthening by the Ilizarov's technique].

Eleven biopsies of bone regenerate during bone lengthening following the Ilizarov technique were studied. They concerned 10 patients with a mean age of 13.5 years. The length of the biopsied regenerate was between 14 and 90 mm, and the delay after the initial procedure was 23 to 502 days. The aim of this study was to get informations on the histology of the regenerate, to quantify osseous data and to propose a surgical strategy. These data were obtained by analyze of non decalcified bone, biopsies were included in a methylmetacrylate block. Measure of the mineralisation speed was determined after a double intake of tetracycline. The bony trabeculations were formed very early, as soon as the third week. They were placed like a thread, that means in an anastomotic system which can quickly become resistant. But is was necessary to keep a lengthening speed under 1 mm per day 0.7 to 0.8 mm per day seems to be the best speed in adolescents. The ossification was of membranous type, without cartilaginous stage. Osteoblastic and osteoclastic activities were extremely rich, even after one year or after the bone healing. The main point was the maturity of the regenerate acquired as soon as the 4th month.

Adolescent↗

[Correction of malunion of femoral fractures by Ilizarov's device in children].

Cast immobilisation of femoral fractures in children may sometimes be subject to important displacements. Absence of survey leads to malunions which may make a secondary correction necessary. In two such cases the authors used Ilizarov's external fixation which allowed correction of both angulation and shortening without direct approach. Rapid healing occurred. The authors made a comparative analysis of the different possibilities for treatment of these severe femoral malunions.

Bony Callus↗

[Supracondylar fractures of the humerus in children: treatment by downward nailing].

Surgical treatment of supracondylar fractures of the humerus in children concerns a limited number of these fractures. That is fractures with great displacement and periosteal rupture, which are reported in our experience of 96 cases treated by an original method. It consists of external reduction stabilized by 2 nails introduced in the middle third of the shaft and diverging in the lower humeral epiphysis. We insist on the use of two X-ray amplifliers in the operative technique. Ninety-four fractures were controlled after 3 months, during nail removal and 81 patients had a follow-up more than one year. Morphological and functional results were appreciated as 75 excellent 15 good and 4 bad. Among the complications encountered we noticed that cubitus varus was very rare. Only 6 controls showed an angle of less than 10 degrees. As compared to the other surgical techniques this method is very encouraging and comforts our indications in unstable third degree fractures, unsuitable for Blount's method, and the great majority of forth degree fractures.

Adolescent↗

[Labor trauma-induced epiphysiolysis of the proximal femur. 4 cases].

The authors report on 4 cases of obstetrical traumatic slipping of the upper femoral epiphysis. Firstly, they emphasise the difficulties of diagnosis because trauma is often missed. In two cases the delivery was a cesarean section (in the same clinic!). Wrong diagnoses are: --neonatal septic arthritis with swelling and inflammation of the hip, lateral deviation of the metaphysis on the x-ray. Nevertheless, there are no signs of an infectious disease and symptoms begin at birth. --congenital dislocation of the hip but clinical testing of stability is painful and doubtful. Secondly, when diagnosis is uncertain, a joint aspiration confirms haemarthrosis, and arthrography shows the displacement of the epiphysis on the metaphysis. Finally, the authors explain their therapeutic procedure: three times orthopaedic treatment with traction and spica cast for 2 months, a pin osteosynthesis in one case. Prognosis was favourable in two cases, but the two other cases present a lateral rotation of the leg in relation to a retroversion of the femoral head.

Adolescent↗

[Use of vascularized bone grafts in surgery of the spine. Apropos of 6 cases].

The Authors report six cases in which a pedicle bone graft was placed by an anterior approach to stabilise a spine deformity. In two cases they used a fibula, in four others it was a cortico-cancellous iliac graft. One case was a neurofibromatosis spine deformity, the second was a Cooley disease, the third one was an hydatidosis, the three remaining cases were spondylolitheses. All patients had been initially operated on by a posterior approach. Fusion was obtained in all cases.

Adolescent↗

Computerised tomography in non-treated congenital hip dislocation.

Computerised tomography, carried out in 5 non-treated cases of congenital dislocation of the hip, shows that the femoral head can move in a large anteroposterior cavity. When the hip is extended the common position of dislocation is lateral superior and slightly anterior to the acetabulum. When the hip is flexed (at a right angle), the femoral head is located posterior and slightly superior to the acetabulum. Dislocation reduction has always been possible. When the hip is flexed a large "click" takes place; whereas if the hip is extended, the "click" is less noticeable, or even absent.

Acetabulum↗

Elastic stable intramedullary nailing of femoral shaft fractures in children.

We report the use of elastic stable intramedullary nailing (ESIN) in 123 fractures of the femoral shaft in children. Flexible rods are introduced through the distal metaphyseal area, and the aim is to develop bridging callus. Early weight-bearing is possible and is recommended. There was one case of bone infection and no delayed union. Complications were minimal, the most common being minor skin ulceration caused by the ends of the rods. A surprising feature was the low incidence of growth changes, with a mean lengthening of only 1.2 mm after an average follow-up of 22 months. Compared with conservative treatment, ESIN obviates the need for prolonged bed rest and is thus particularly advantageous for treating children.

Adolescent↗

[Prognosis of fractures of the lower end of the femur in children and adolescents. Apropos of 96 cases].

A multicentre study undertaken in a number of orthopaedic and traumatology departments of hospitals in the East of France have made it possible to bring together, over 10 consecutive years, 96 fractures of the lower end of the femur in children and adolescents. The analysis of this retrospective series agrees with the findings in the literature both in its clinical features and the methods of treatment. The results were very good in 84 per cent of cases. The authors feel that the standard scoring systems are too optimistic and they prefer an analytic description of the complications which presented in 54 per cent of cases with 13 per cent of malunions, 16 per cent of epiphysiodeses and 7 per cent of inequalities of limb length greater than 10 mm. The etiology and pathology of these diverse complications is reviewed. Vascular lesions seem to play an unimportant role. The prognosis, as defined, seems to be realistic since this work has taken account of a large proportion of the fractures occurring during the same period in the same region.

Adolescent↗

[A computer-assisted study of the surgical treatment of talipes equinovarus].

One-hundred-and-eleven club feet were treated surgically and followed up for more than three years. A computer analysis of the results, compared with the information contained in the operative notes, provided a better assessment of the effectiveness of each surgical procedure. Resection of capsular structures did not give better results than simple division. Posterior capsulotomy of the sub-taloid joint did not alter the separation between the talus and the calcaneus in lateral radiographs. Division of the plantar aponeurosis and lengthening of the long toe flexors seemed to diminish the frequency of secondary cavus deformity. Lengthening of the tibialis anterior improved the range of plantar-flexion of the ankle and reduced the occurrence of residual adduction of the forefoot and elevation of the first metatarsal. Finally, to avoid weakening of muscles, it proved to be vital to preserve the tendon sheaths and to avoid longitudinal tendon division followed by suture, which favours adhesions and tethering of tendons. The authors describe the details of the stages of surgical release. It is not a matter of a new approach to the treatment of club foot but a combination of detailed modifications aiming to produce a perfect final result.

Child↗

The history of pediatric surgery in France.

In 1741, Nicolas Andry, counsellor of King Louis XV, published a book about "orthopedics," inventing this word. The book is interesting as the author refers to beliefs and habits of the time. In 1864, Guersant published Notes About Pediatric Surgery, a real textbook which was translated into English and German and dealt with the importance of children's psychological training, anesthesia, and water or mother's milk after the operation, and also described tracheotomy, draining of cervical adenitis, and lithotrity. The classification of bone affections was still very confused. Tuberculosis and syphilis have an important place; hypospadias is not treated by surgery. In 1905, Froehlich published Pediatric Surgery Studies dealing exclusively with visceral surgery and demonstrating progress compared to Guersant's study. In 1906, Kirmisson published Pediatric Surgical Textbook, containing the first discussion of radiology and the description of the pathology of the omphalomesenteric duct and of other congenital malformations. Osteomyelitis was given its proper name, and cervical fistulas were explained. In 1914, A. Broca achieved further progress describing treatments of megacolon, intussusception, and the operation of Fredet Ramstedt. The book by Ombredanne, already out of date at the time of its publication, showed that he was not aware of the wartime, progress achieved by Ladd and Gross in the USA. French publications have diminished since then, and French pediatric surgery is still trying to find a precise identity.

France↗