Alargamiento óseo con clavo intramedular magnético experiencia preliminar y lecciones aprendidas / Bone lengthening with magnetic intramedullary nail preliminary experience and learned lessons

OBJETIVOS: Mostrar resultados, complicaciones y lecciones aprendidas utilizando el clavo intramedular magnético (IML, Intramedullary Magnetic Lengthener) en un grupo de pacientes sometidos a alargamiento óseo. PACIENTES Y MÉTODOS: Entre enero 2017 y diciembre 2019, 9 pacientes (15 segmentos), edad entre 15 y 39 años, fueron sometidos a alargamiento óseo con IML: 5 pacientes tuvieron alargamiento femoral bilateral por talla baja, 1 paciente se sometió a alargamiento de Piernas bilateral por Tibia vara y acortamiento mesomélico y 3 recibieron alargamientos femorales unilaterales por discrepancia de longitud de extremidades. Todos fueron operados por el mismo cirujano, con técnica standard. Se indicó kinesiterapia al menos 5 veces por semana durante la fase de distracción. RESULTADOS: En todos se logró el objetivo de alargamiento planteado. No hubo complicaciones intra ni postoperatorias graves (TVP, TEP, Embolia grasa), ni fallas del sistema distractor. Un paciente desarrolló contracturas articulares de ambas rodillas por no adhesión a Kinesiterapia. Ninguno requirió aporte de injerto óseo, sin embargo en 2 pacientes de alargamiento de Fémur bilateral, se presentó deformidad en varo, que hizo necesario recambio a clavo convencional y un paciente desarrolló una parálisis transitoria del Nervio Peroneo común. CONCLUSIONES: El advenimiento de los IML significó un gran avance en el campo de la osteogénesis por distracción, sin embargo, aún se trata de un procedimiento complejo, que debe ser planificado cuidadosamente para minimizar los riesgos y complicaciones. Una selección meticulosa del paciente y la evaluación física y psicológica previa, son fundamentales para el éxito del procedimiento. Los casos bilaterales requieren de un seguimiento cercano, por el riesgo de falla del implante.

objective: We show our results, complications and lessons learned using the Intramedullary Magnetic Lengthener (IML) in a group of patients who were subjected to bone lengthening. PATIENTS AND METHODS: Between January 2017 and December 2019, 9 patients (15 segments), aged between 15 and 39 years, underwent bone lengthening with IML: 5 patients had bilateral femoral lengthening due to short stature, 1 patient had bilateral leg lengthening due to Tibia vara and mesomelic shortening and 3 had unilateral femoral lengthening for limb length discrepancy. All were operated by the same surgeon, with standard technique. Physical therapy was indicated at least 5 times per week during the distraction phase. RESULTS: In every case, the proposed lengthening amount was achieved. There were no serious intraoperative or postoperative complications (DVT, Pulmonary Embolism, Fat Embolism), nor failures of the distractor system. One patient developed knee joint contracture due to non-adherence to Physical therapy. None required bone grafting, however, in 2 patients with bilateral Femur, a varus deformity appeared, which required nail exchange with a conventional trauma nail. One case developed a transit common Peroneal Nerve palsy. CONCLUSIONS: IMLs represent a great advance in the bone lengthening realm, however, it is still a complex procedure, which must be carefully planned to minimize risks and complications. Meticulous patient selection and prior physical and psychological evaluation are essential to the success of the procedure. Bilateral cases need a closer follow up, because implant failure is a potential risk.

Influence of different orientations and rates of bidirectional distraction osteogenesis of the mandibular corpus: a three-dimensional study

Objective: The objective of this study was to evaluate the biomechanical effect of mandibular corpus distraction osteogenesis with different orientations and rates. Materials and Methods: A three-dimensional model of the mandible was created. The vertical surgical cut was made, the force was applied horizontally in a bidirectional manner within two orientations: parallel to the occlusal plane and parallel to the inferior border of the mandible with three rates (0.5mm, 1mm and 1.5mm). Results: The maximum values for von Mises stress when the force was applied parallel to the inferior border of the mandible with all three rates were smaller than those with force direction parallel to the occlusal plane. The displacement in all three directions x, y, and z were not parallel and prominent in the anterior part of the mandible, while the movement at the posterior part is negligible, x and z displacement were bigger when force was applied parallel to the inferior border of the mandible, z displacement was more prominent than x and y displacement, both directions produced upward rotation of the mandible, this rotation was more noticeable when the force was applied parallel to the inferior border of the mandible. Conclusions: A vertical cut can be used in the patient with a long anterior face. This site of distraction achieves more lengthening of mandible than expansion.

Distracción ósea mandibular con aparatos reabsorbibles: reporte de tres casos / Mandibular distraction osteogenesis with resorbable devices: report of three cases

La micrognatia e hipoplasia unilateral mandibulares son un rasgo característico en algunos síndromes que incluyen defectos faciales, pero también se pueden presentar como secuelas de traumatismo sobre los tejidos duros del complejo maxilofacial. Dichas alteraciones adquiridas o congénitas, ocasionan grandes trastornos estéticosy funcionales. La distracción ósea descrita por Ilizarov como un método de elongación de los huesos largos, aplicado al área maxilofacial en años recientes, ha demostrado ser una técnica eficaz para la corrección de estos defectos. En este artículo se reportan tres casos de corrección de deformidades mandibulares en niños mediante la técnica de distracción ósea utilizando aparatos reabsorbibles, siendouna de sus ventajas el que no se requiere una segunda intervenciónquirúrgica para su retiro. Los pacientes fueron intervenidos en la Unidad Médica de Alta Especialidad (UMAE) No. 71 del Instituto Mexicano del Seguro Social, en donde desde hace 10 años se ha estadoutilizando el método de distracción ósea para manejo de deformidades mandibulares en niños con muy buenos resultados.

Mandibular micrognathia and unilateral mandibular hypoplasia are atypical feature of certain facial deformity syndromes, though can alsoappear as sequelae of maxillofacial hard tissue trauma. Acquired orcongenital alterations of this nature can have a signifi cant aestheticand functional impact. Ilizarov describes distraction osteogenesis as amethod for lengthening long bones, one that in recent years has beenapplied to the maxillofacial region and proved an eff ective technique forcorrecting these defects. This article reports three cases of mandibulardeformity correction in children, carried out using the distraction osteogenesistechnique with resorbable devices. One of the advantagesof using such devices is that the need for a second surgical interventionto remove them is eliminated. All patients were treated at AdvancedSpecialty Medical Unit (UMAE) 71 of the Mexican Institute of SocialSecurity, which, for the last ten years, has been using the distractionosteogenesis method to correct mandibular deformities in children,with optimal results.

Síndrome de Crouzon: características clínicas. Relato de casos clínicos / Crouzon Syndrome: clinical features. Clinical case reports

A Síndrome de Crouzon é uma doença hereditária que surge com o fechamento prematuro das suturas da base do crânio, resultando em um crescimento compensatório na direção em que as suturas permanecem abertas. A síndrome é caracterizada por deformidade craniofacial com redução do comprimento das bases anterior e posterior do crânio, tendo como principais características clínicas a exoftalmia, hipertelorismo e a hipoplasia do terço médio da face. / Objetivo / Relatar os casos clínicos de uma família, onde três de seus membros são portadores da Síndrome de Crouzon, apresentando, assim, as características clínicas e as formas de tratamento. / Relato / No caso 1, a paciente foi submetida à cirurgia de avanço frontofacial convencional; e nos casos 2 e 3, os pacientes foram submetidos ao avanço frontofacial com distração osteogênica. Todos foram operados em idade precoce, necessitando de tratamento ortodôntico e cirúrgico para finalização do caso. / Conclusão / Os tratamentos cirúrgico, ortopédico e ortodôntico são uma combinação perfeita para a correção das deformidades craniofaciais, sendo a distração osteogênica do terço médio da face uma técnica cirúrgica de grande sucesso, que apresenta menor morbidade e excelentes resultados.

Treatment of midfacial hypoplasia in syndromic and cleft lip and palate patients by means of a rigid external distractor (RED)

INTRODUCTION: Distraction Osteogenesis (DO) became an alternative for the treatment of severe craniofacial skeletal dysplasias. The rigid external distraction device (RED) is successfully used to advance the maxilla and all the maxillary-orbital-frontal complex (monobloc) in children, adolescents and adults. This approach provides predictable and stable results, and it can be applied alone or with craniofacial orthognathic surgical procedures. OBJECTIVE: In the present article, the technical aspects relevant to an adequate application of the RED will be described, including the planning, surgical and orthodontic procedures.

INTRODUÇÃO: a Distração Osteogênica (DO) tornou-se uma alternativa para o tratamento das displasias craniofaciais esqueléticas severas. O aparelho distrator externo rígido (RED) é utilizado com êxito para avançar a maxila e todo o complexo maxilar-orbital-frontal (monobloco) em crianças, adolescentes e adultos. Essa abordagem proporciona resultados previsíveis e estáveis, podendo ser aplicada isoladamente ou junto a procedimentos cirúrgicos ortognáticos craniofaciais. OBJETIVO: no presente artigo, serão descritos os aspectos técnicos pertinentes a uma adequada aplicação do RED, incluindo o planejamento, procedimentos cirúrgicos e ortodônticos.

Experimental model of distraction osteogenesis in edentulous rats

Distraction osteogenesis (DO) is a surgical technique producing bone lengthening by distraction of the fracture callus. Although a large number of experimental studies on the events associated with DO of craniofacial skeleton have been reported, the few employing rat mandibular bone DO used complicated designs and produced a small volume of newly formed bone. Thus, this study aims to present an original experimental model of mandibular DO in edentulous rats that produces a sufficient quantity and quality of intramembranous bone. Eight male Wistar rats, weighing 75 g, underwent extraction of lower molars. With rats weighing 350 g, right mandibular osteotomy was performed and the distraction device was placed. The distraction device was custom made using micro-implants, expansion screws, and acrylic resin. Study protocol: latency: 6 days, distraction: » turn (0.175 mm) once a day during 6 d, consolidation: 28 d after distraction phase, sacrifice. DO-treated and contralateral hemimandibles were dissected and compared macroscopically and using radiographic studies. Histological sections were obtained and stained with H&E. A distraction gap filled with newly formed and mature bone tissue was obtained. This model of mandibular DO proved useful to obtain adequate quantity and quality of bone to study bone regeneration.

Limb Angular Deformity Correction Using Dyna-ATC: Surgical Technique, Calculation Method, and Clinical Outcome

PURPOSE: Dyna-ATC is a unilateral external fixator with angulator, lengthener, and translator, which allows for angular correction and compensation of the secondary displacement during angular correction. The purpose of this study is to introduce surgical technique and calculation methods and to evaluate the clinical outcome of angular deformity correction using Dyna-ATC. MATERIALS AND METHODS: The amounts of secondary displacement were calculated with the distances between axis of correction of angulation, Center of Rotational Angulation, and osteotomy and the amount of angular deformity. The rate of angular correction was determined to distract the corticotomy at 1 mm/day. Clinical and radiographic evaluation was performed on 13 patients who underwent deformity correction using Dyna-ATC. There were 8 proximal tibia vara, 1 tibia valga, 2 varus and 4 valgus deformities on distal femur. One patient underwent pelvic support femoral reconstruction. Concomitant lengthening was combined in all femur cases. Mean age at surgery was 17.5 years (7 to 64). RESULTS: All but one achieved bony healing and normal alignment with the index procedure. Mean mechanical axis deviation improved from 31.9 mm to 3.0 mm. The average amount of angular correction was 11.0degrees on tibiae and 10.0degrees on femora. The average length gain on femora was 6.4 cm, and the healing index averaged to 1.1 mo/cm. One patient underwent quadricepsplasty and one patient had three augmentation surgeries due to poor new bone formation. CONCLUSION: We believe that Dyna-ATC is a useful alternative to bulky ring fixators for selective patients with angular deformity less than 30 degrees in the coronal plane around the knee joint.

Anterograde removal of broken femoral nails without opening the nonunion site: a new technique

OBJECTIVE: We describe a new technique for removing the distal fragments of broken intramedullary femoral nails without disturbing the nonunion site. METHODS: This technique involves the application of an AO distractor prior to the removal of the nail fragments, with subsequent removal of the proximal nail fragment in an anterograde fashion and removal of the distal fragment through a medial parapatellar approach. Impaction of the fracture site is then performed with a nail that is broader than the remaining fragmented material. RESULTS: Nails were removed from five patients using the technique described above without any complications. After a mean follow-up period of 61.8 months, none of these patients showed worsened knee osteoarthritis. CONCLUSION: The original technique described in this article allows surgeons to remove the distal fragment of fractured femoral intramedullary nails without opening the nonunion focus or using special surgical instruments.

Avanço fronto facial em monobloco com distração osteogência para tratamento das craniofaciossinostoses: comparação entre 2 distratores / Monobloc fronto facial advancement with distraction osteogenesis for craniofaciosynostosis: comparison between 2 distractors

O tratamentodas deformidades craniofaciais foi revolucionado com o advento da técnica do alongamento ósseo gradual denominada distração osteogênica. Oito pacientes com diagnóstico de craniofaciossinostose foram submetidos a avanço fronto facial em monobloco com distração osteogência. Os pacientes foram divididos em 2 grupos de 4 pacientes. No grupo 1 (n=4), o avanço fronto facial foi realizado utilizado os distratores externos fabricados na SOBRAPAR. A idade média do grupo 1 foi de 10,5 anos. O tempo de seguimento do grupo 1 foi de 11 anos. No grupo 2 (n=4), o avanço fronto facial foi realizado utilizando os distratores internos fabricados nos USA pela KLS Martin - USA. A idade média do grupo 2 foi de 8,7 anos. O tempo de seguimento do grupo 2 foi de 1,5 anos. Traçados cefalométricos utilizando o padrão Ricketts foram utilizados para comparação de resultados. O índice de avanço médio do grupo foi 18,3 mm. As variações cefalométricas do grupo 1 foram: SNA: 7º, SNB: -3º. O índice de avanço médio do grupo 2 foi 10,7 mm. As variações cefalométricas do grupo 2 foram: SNA: 8.1º, SNB: -3,4º. Em ambos os grupos, os pacientes ficaram com enoftalmia temporária e com oclusão classe 2. No caso do grupo 1, a classe 2 envoluiu para classe 1 com o passar do tempo. No grupo 2, os pacientes permanecem em classe 2. Os pacientes dos 2 grupos tiveram boa evolução. A retrusão do terço médio, o exorbitismo, bem como o déficit respirat´roio foi tratado satisfatoriamente em ambos os grupos. Maior avanço ósseo do terço médio foi necessário no grupo 1, provavelmente decorrente de uma menor estabilidade óssea durante o processo de alongamento ósseo gradual.

Bone tissue microscopic findings related to the use of diode laser (830etam) in ovine mandible submitted to distraction osteogenesis

PURPOSE: To analyze the microscopic characteristics of the effect of Gallium-Aluminum Arsenid diode laser (GaAlAs - 830etam) applied during the activation and consolidation period to ovine mandibles submitted to distraction osteogenesis. METHODS: Eighteen sheep underwent surgery in order to have bone distractors implanted in the left side of the jaw area. They were divided into three groups: 1 - Control; 2 - Laser irradiation during the activation period; 3 - Laser irradiation during the fixation period. The irradiation was carried out in five sessions, on every other day, with 4,0J/cm² doses applied to four pre-established areas, totaling 16J per session. After four days of latency under post-operative care, ten days of distractor activation (at 1mm/day) and twenty-one days of fixation the animals were sacrificed and the devices removed for microscopic analysis. RESULTS: The groups that received laser irradiation (GaAlAs) presented a greater amount of mineralized bone trabeculae when compared to the Control Group. Despite that, cartilaginous tissues were also found in Group 2. CONCLUSION: The laser has been more favorable when used in the consolidation period, after bone elongation.

OBJETIVO: Avaliar as características microscópicas do efeito do laser diodo de Arsenieto de Gálio-Alumínio (AsGaAl - 830etam), aplicado no período de ativação e consolidação de mandíbulas de ovelhas submetidas a distração osteogênica. MÉTODOS: Dezoito ovinos foram submetidos a procedimento cirúrgico para colocação de distrator ósseo em região de mandíbula do lado esquerdo, sendo divididos em três grupos: 1 - Controle; 2 - Irradiação de laser no período de ativação; 3 - Irradiação de laser no período de contenção. As irradiações foram feitas em cinco seções em dias alternados, com doses de 4,0J/cm² em quatro pontos pré-determinados, somando 16J por seção. Após quatro dias de latência no pós-operatório, 10 dias de ativação do distrator (1 mm/dia) e 21 dias de contenção os animais foram mortos e as peças removidas para análise microscópica. RESULTADOS: Os resultados foram que os grupos irradiados com laser (AsGaAl) apresentaram maior disposição de trabéculas ósseas mineralizadas em relação ao grupo controle, contudo, no Grupo 2 foi observada a presença de tecido cartilaginoso. CONCLUSÃO: O laser atuou de forma mais favorável quando utilizado no período de consolidação, após o alongamento ósseo.

Alargamiento de metacarpiano: caso clínico / Lengthening of metacarpian: clinical case

Braquimetacarpiano o braquidactilia tipo E es el acortamiento anómalo de un metacarpiano o de un dedo. Esta anomalía corresponden al 5.2 por ciento de todas las malformaciones de la mano, siendo los metacarpianos 3º, 4º y 5º los más frecuentemente afectados (1-3). El problema se diagnóstica durante el crecimiento cuando se hace evidente un dedo más corto y/o el hundimiento del nudillo al cerrar el puño. Los procedimientos de elongación de metacarpianos actualmente más utilizados son: la distracción aguda y la colocación de injerto óseo. En esta revisión se muestra el caso clínico de una paciente tratada mediante la utilización de un tutor monoplanar externo, técnica relativamente nueva. En este caso se logró un alargamiento de 18 milímetros en un período de 4 meses, con excelentes resultados estéticos y funcionales.

Correction of shortening and/or angular deformities by distraction osteogenesis using AO-tubular fixator.

Eighteen patients (20 bony segments) who had shortening and/or angular deformities were treated by distraction osteogenesis using AO-tubular external fixator. The mean angular correction was 18.9 degrees (range, 8-40 degrees). Of the group in whom shortening and angulation was corrected, the mean length gained was 4.2 cm (3-6 cm). The mean treatment time was 4.9 months (range, 2-13 months) and the mean follow-up was 12 months after removal of the fixator (range, 3-30 months). Delayed union with loosening of the fixator occurred in one patient which resulted in residual shortening of 1.5 cm. The author's technique of distraction osteogenesis using AO-tubular fixator with the new distraction rate of 1 mm/48 h (1 mm/step) could adequately correct shortening and/or angular deformities. No extra equipment was needed other than the readily-available AO-tubular fixation systems. No serious complications such as neurovascular injury were encountered.

Cubitus varus--correction by distraction osteogenesis.

Cubitus varus deformity in thirty children was corrected by gradual medial opening wedge osteotomy. The osteotomy was stabilized and distracted by simple external fixator-cum-distractor. The patients of both sexes and age from 6 to 14 years, had varus deformity from 17 degrees to 43 degrees. We achieved good to excellent results in 28 cases as regards to correction of deformity and range of motion at elbow joint. None of the cases had neurological deficit or permanent stiffness. One case had fair result due to under-correction and another case had a poor result as osteotomy united before correction. The main complication faced was superficial pin-site infection particularly in summer season and a in fatty children but was managed by good pinsite dressing and care. The technique has been found to be quite effective, technically simple, cosmetically acceptable and with little, if any, lazy S deformity.