Clinical results and complication rates of lower limb lengthening in paediatric patients using the PRECICE 2 intramedullary magnetic nail: a multicentre study.

Implantable intramedullary nail lengthening devices (e.g., PRECICE 2 system) have been proposed as alternative method to external fixation for lower limb lengthening surgery. The aim of this study was to analyse our outcomes and complications using the PRECICE 2 (P2) nail system and review them in light of the existing literature. A retrospective multicentre study was conducted on patients <18 years, who were treated for limb lengthening using the P2 system. The inclusion criteria were a limb length discrepancy ≥ 30 mm and a follow-up ≥6 months after the end of treatment. A total of 26 (15 males) patients were included, average age was 14.7 ± 2.3 years; 26 nails (21 femur, 5 tibia) were implanted. The average goal lengthening was 49.4 ± 12.4 mm, while average achieved lengthening was 44.4 ± 11.6 mm. Average distraction and consolidation indexes were 11.9 ± 2.1 days/cm and 25.1 ± 8.1 days/cm, respectively. Nail accuracy and reliability were 91.1% and 88.5%, respectively. A total of five problems (joint contractures), one obstacle (femur fracture) and three complications (hip joint subluxation, deep infection and nail running back) were encountered. The P2 nail system is a valid alternative to external fixator for limb lengthening in young patients with no significant angular or rotation deformities. Our study confirms a favourable complication rate and available evidence from literature suggests a lower complication rate than external fixator systems. Nevertheless, surgeons should keep a watchful eye on risk of joint subluxation and mechanical complications with intramedullary lengthening.

What's New in Pediatric Limb Lengthening and Deformity Correction?

Over the past 5 years, published literature regarding treatment of pediatric limb deformity and limb length discrepancy demonstrates much interest in better understanding, categorizing and treating these challenging problems. Many studies explore expanding and refining indications for traditional treatment methods like guided growth techniques. Other studies have evaluated the results of new techniques such as lengthening via mechanized intramedullary nails. Additionally, series comparing older and newer techniques such as lengthening with external devices versus mechanized nails are becoming increasingly available.

New Technologies in Pediatric Deformity Correction.

The ability to correct limb deformities is one of the core elements of pediatric orthopedics. The term, orthopedics, is derived from the Greek language and means straightening (ortho) children (paidos). New advances in the evaluation and management of children with limb alignment or limb length issues are constantly appearing. This review highlights some of the recent technologies that have been developed to improve the care of these children.

Lengthening of newly formed humerus after autologous fibula graft transplantation following intercalary tumor resection.

Secondary limb lengthening after intercalary bone resection in pediatric patients is still challenging. After the resection, a free fibula autograft can be used to reconstruct the osseous gap. However, in particular in young pediatric patients, insufficient growth of the epiphyseal plate after transplantation may lead to a significant limb-length discrepancy (LLD). In this case, the autograft was used for limb lengthening. We report on the lengthening of a humerus regenerate after fibula autograft transplantation into a humeral defect in a pediatric/young adolescent patient. Because of LLD, she underwent callus distraction of the humerus regenerate after transplantation of a fibula autograft using a unilateral external fixator device. An 18-year-old female patient with status postintercalary proliferating chondroma resection (at the age of 7 years) required treatment for correction of a 13 cm humerus shortening. She reported no pain, had no functional limitations, and had a full range of motion of the shoulder and elbow joint. She complained about her short humerus and overall body scheme. A unilateral external fixator device for callus distraction was applied to the transplanted humerus regenerate after free fibula autograft transplantation. Bone lengthening was performed by distraction (2×0.5 mm/day). After 62 days and a lengthening of 6 cm in total, bone distraction was stopped mainly to avoid any complication. At this time, there was no limitation in the range of motion. No nerve palsy or other problems occurred at any time of the distraction. In pediatric patients, the transplantation of a fibula autograft is a well-established option to bridge an osseous gap after intercalary bone resection. This case report shows that even the humerus regenerate after fibula autograft transplantation has excellent potential for callotasis and bone remodeling and therefore bone lengthening in patients with LLD is an option even after transplantation of an autograft. This method provides a new therapeutic option for patients with LLD after fibula transplantation.

The role of the intramedullary implant in limb lengthening.

Limb lengthening is now an accepted practice in orthopaedic surgery. The principles of distraction osteogenesis have become well established with the use of external fixators, utilizing both monolateral and ring fixators. Corticotomy technique, frame stability, lengthening rate and rhythm all contribute to the formation of bone regenerate and tissues. Complications are however common including pin-site infection, soft tissue tethering from the pins and wires resulting in pain, regenerate deformity from soft tissue forces or fracture following frame removal and patient intolerance of the frames during treatment. Surgical techniques have changed to try and minimise these complications. The use of intramedullary nails have been used in conjunction with an external fixator or inserted after lengthening has been achieved, to reduce fixator time and prevent regenerate deformity. Implant innovation has led to the production of intramedullary lengthening nails. The initial devices used ratchet mechanisms with rotation of the bone fragments to achieve lengthening (Bliskunov, Albizzia and ISKD). More accurate control of lengthening and a reduction in pain, resulting from the manual rotation of the leg required to achieve the ratchet progression, was achieved by the use of a transcutaneous electrical conduit powered by external high frequency electrical energy (Fitbone). The most recent implant uses an external remote controller which contains two neodymium magnets. These are placed over the nail on the skin and rotate which in turn rotates a third magnet within the intramedullary nail (Precice). This magnet rotation is converted by a motor to extend or retract the extendible rod. There are multiple nail sizes and lengths available, and early results have shown accurate control with few complications. With such promising outcomes the use of this lengthening intramedullary nail is now recommended as the implant of choice in femoral lengthening. This article is an historical account of the intramedullary device and the impact on limb lengthening.

Tratamiento de la escoliosis juvenil: aumentar el tiempo entre alargamientos con la técnica de barras de crecimiento no debe comprometer necesariamente el crecimiento torácico / Treatment of juvenile scoliosis: increasing the lengthening interval with the growing rod technique should not necessarily compromise thoracic growth

Objetivo. Evaluar el crecimiento longitudinal del tórax y el control de la deformidad en una serie de pacientes con escoliosis juvenil tratados con barras de crecimiento aumentando los intervalos de tiempo entre alargamientos más de seis meses. Material y métodos. Estudio retrospectivo de ocho pacientes midiendo las siguientes variables: el ángulo de Cobb, la traslación vertebral apical, el balance coronal, la longitud torácica T1-L1, la cifosis torácica T5-T12, el ángulo de cifosis de unión proximal (CUP) y la lordosis lumbar. Se registraron las complicaciones. Resultados. Se evaluaron cinco escoliosis idiopáticas y tres casos de sindrómica (media de edad 9,4 ± 1,5 años). Se realizó una cirugía inicial y un promedio de dos retensados por paciente. El tiempo medio entre retensados fue de 15,7 meses. La corrección coronal final de la curva principal fue del 58%. La longitud torácica (T1-L1) preoperatoria fue de 20,8 cm, postoperatoria de 24,4 cm, y final de 26 cm. Al final del seguimiento el crecimiento medio del tórax fue de 5,2 cm. La cifosis preoperatoria (T5-T12) fue 33,5°, y final 32,1°. El cambio en el ángulo CUP fue de 2,5° en el seguimiento final. La mayoría de las complicaciones estuvieron relacionadas con la instrumentación. Se encontraron dos infecciones superficiales de la herida. Conclusión. En pacientes con escoliosis juvenil en formas «menos graves» tratados mediante barras de crecimiento, es posible espaciar los alargamientos más de un año y con ello disminuir el número de cirugías y al mismo tiempo controlar la deformidad y permitir el crecimiento longitudinal torácico (AU)

Objective. Serial lengthening with growing rods is recommended every six months for the treatment of early onset scoliosis. The objective of this study was to evaluate the longitudinal growth of the thorax and control of the deformity in a series of patients with juvenile scoliosis when time intervals were increased between lengthenings. Material and methods. Retrospective study of eight patients. The following variables were measured: the Cobb angle, the apical vertebral translation, the coronal balance, thoracic T1-L1 length, thoracic T5-T12 kyphosis, the proximal junctional kyphosis (PJK) angle, and the lumbar lordosis. Complications were recorded. Results. Five idiopathic and three syndromic scoliosis cases (mean age 9.4 ± 1.5 years) were evaluated. The initial surgery was followed by with an average of two distractions per patient. The mean time between distractions was 15.7 months. The final coronal main curve correction was 58%. Apical translation and coronal balance were improved and maintained after the surgeries. The thoracic (T1-L1) preoperative length was 20.8 cm, the postoperative length was 24.4 cm, and the final length was 26 cm. At the end of follow-up, the average growth of the thorax was 5.2 cm. The preoperative (T5-T12) kyphosis was 33.5°, and final 32.1°. The change in the PJK angle was 2.5° at the end of follow-up. Most complications were related to instrumentation. Two superficial wound infections were encountered. Conclusion. For less severe juvenile scoliosis patients treated with growing rods, spacing out lengthenings over more than a year can decrease the number of surgeries, while still controlling the deformity and allowing longitudinal thoracic growth (AU)

Repercusión del tratamiento fisioterápico en los tratamientos quirúrgicos de alargamiento óseo. A propósito de un caso / Impact of physiotherapy in the surgical treatment of bone lengthening. A case report

La incidencia de las complicaciones derivadas de los alargamientos óseos cada vez supone menos en la recuperación íntegra de estos pacientes gracias al abordaje multidisciplinar que reciben, siendo la fisioterapia un elemento clave. El objetivo del estudio es conocer los efectos beneficiosos que logra la fisioterapia en procesos de alargamientos óseos en relación con la amplitud articular y al tono muscular, así como en la prevención de complicaciones a propósito de un caso. Nuestra paciente, diagnosticada de dismetría de miembros inferiores, se somete a elongación tibial mediante una distracción progresiva a partir de fijadores externos distractores. El seguimiento realizado valoró la amplitud articular mediante goniometría manual, tono muscular mediante la escala de Daniels, existencia de linfedema y longitud del miembro mediante cinta métrica y el dolor percibido mediante escala visual analógica. Como resultados, destacamos la ganancia completa del rango articular y la prevención del equinismo y linfedema secundario(AU)

The incidence of complications of bone lengthening is increasingly less in the full recovery of these patients thanks to the multidisciplinary approach received, physiotherapy being a key element. This study has aimed to determine the beneficial effects achieved by physiotherapy in bone lengthening procedures in relationship to range of motion and muscle tone and in the prevention of complications based on a case report. Our patient who was diagnosed with lower limb dysmetria underwent tibial lengthening by gradual distraction from distracting external fixator. The monitoring performed evaluated joint range by means of manual goniometry, muscle tone scale by the Daniels scale, existence of lymphedema and limb length by measuring tape and perceived pain by the Visual Analog Scale. Standing out among the results are the full gain of joint range and prevention of equinus and secondary lymphedema(AU)

Resultados de alargamiento tibial con la técnica de ilizarov

Entre enero de 1992 y junio de 1997, 21 tibias en 21 pacientes se alargaron usando la técnica de ilizarov. El seguimiento fue de 5 meses a 5 años. La etiología del acortamiento en el miembro fue adquirido en 12 tibias y congénitas en 9. 20 tibias tuvieron tratamiento unifocal y una bifocal. El promedio de alargamiento fue de 6.0 cm, con un rango de 4 a 12 cm, el cual fue equivalente al 22.6 por ciento del promedio total de aumento en la longitud del segmento afectado, rango de 8.8 por ciento a 41 por ciento. El tiempo de corticalización del alargamiento fue en promedio 7 meses, con un rango de 4 a 12 meses. Las complicaciones a nivel óseo requirieron 7 cirugías adicionales, incluyendo 4 recolocaciones de clavos, 2 correcciones de deformidad angular en antecurvatum medinate recolocación del fijador y una por articotomía incompleta. 5 pacientes presentaron contractura en flexión de rodilla, 3 se movilizaron bajo anestesia y a 2 se les realizó deflexión de rodilla. Los resultados de este trabajo confirman que no hay alargamiento sin riesgo, pero existen ventajas evidentes con el método ilizarov, apoyo precoz, corrección simultánea de deformidades angulares coexistentes, lo que es difícil con otras técnicas quirúrgicas. La tasa de alargamiento y el índice de alargamiento obtenido en esta serie confirman el uso continuo de una distracción gradual previa selección del paciente.

[Bone lengthening. History of the development and field of applications]. / Knogleforlaengelse. Udviklingshistorien og anvendelsesmulighederne.

Leg lengthening has been performed since early in this century. The first successful lengthening was reported in 1905. Leg lengthening evolved from forced lengthening of the bone during anaesthesia, through use of cortical bone grafts, plate and screws to callus distraction (callotasis). Development of external fixators and evolution of biological concepts of bone regeneration has been important. In 1951 Ilizarov developed his apparatus. Ilizarov pioneered the biology of bone and soft-tissue regeneration. He performs a percutaneous subperiosteal corticotomy and waits five to seven days prior to distraction with a rate of 0.25 mm of length four times each day. The method has increased the opportunities in reconstructive bone surgery. The technique is difficult with many problems and obstacles which can be overcome.