Limb lengthening and deformity correction with externally controlled motorized intramedullary nails: evaluation of 50 consecutive lengthenings

Abstract

Background and purpose — Limb lengthening with an intramedullary motorized nail is a relatively new method. We investigated if lengthening nails are reliable constructs for limb lengthening and deformity correction in the femur and the tibia.Patients and methods — 50 lengthenings (34 Precice and 16 Fitbone devices) in 47 patients (mean age 23 years [11–61]) with ≥12 months follow-up are included in this study. 30 lengthenings were done due to congenital and 20 because of posttraumatic deformity (21 antegrade femora, 23 retrograde femora, 6 tibiae). Initial deformities included a mean shortening of 42 mm (25–90). In 15 patients, simultaneous axial correction was done using the retrograde nailing technique.Results — The planned amount of lengthening was achieved in all but 2 patients. 5 patients who underwent simultaneous axial correction showed minor residual deformity; unintentionally induced minor deformities were found in the frontal and sagittal plane. The consolidation index was 1.2 months/cm (0.6–2.5) in the femur and 2.5 months/cm (1.6–4.0) in the tibia. 2 femoral fractures occurred in retrograde femoral lengthenings after consolidation due to substantial trauma. There were 8 complications, all of which were correctable by surgery, with no permanent sequelae.Interpretation — Controlled acute axial correction of angular deformities and limb lengthening can be achieved by a motorized intramedullary nail. A thorough preoperative planning and intraoperative control of alignment are required to avoid residual and unintentionally induced deformity. In the femur relatively fast consolidation could be observed, whereas healing was slower in the tibia.

Alargamiento Oseo Con Clavo Intramedular Magnetico Experiencia Preliminar y Lecciones Aprendidas

“…Aunque esos últimos tendrían la ventaja de permitir la corrección de deformidades en forma simultánea al alargamiento, existen varios trabajos que han demostrado la eficacia del uso de esos implantes para fijar correcciones agudas y luego realizar alargamiento progresivo. [10][11][12][13][14] En esta serie, 3 pacientes (5 segmentos) presentaban deformidades concomitantes, que fueron corregidas durante la cirugía. La clave del éxito en esos casos, es el uso de tornillos de bloqueo (Poller screws).…”

“…Los tiempos de consolidación, medidos con el HI fueron de 46,5 días/cm. Aunque esa cifra es similar a la reportada en diversos estudios 7,12,23,24 la presente serie incluye tanto alargamiento de Fémur como Tibia, en pacientes de diferentes edades y con diagnósticos de base diferentes, lo que hace poco fiable la comparación.…”

Deformite analiz ve planlama prensipleri

“…Buna angulasyon-translasyon deformitesi denir. [7,[15][16][17][18] Translasyon deformiteleri: Frontal, sagittal ve oblik planda oluşabilir. Translasyon yönü distal kemiğin proksimal uca olan pozisyonuna göre belirlenir.…”

Uzayabilen motorlu çivilerle deformite düzeltme ve uzatma

“…Eğer kanal geniş ise veya akut düzeltme yapıldıysa oluşabilecek deformiteyi engellemek için polar vidası uygulanmalıdır (Şekil 3). [16] Femur proksimal girişlerinde erişkinlerde piriformis girişinin (Şekil 4) tercih edilmesi ile uzama esnasında oluşabilecek varus deformitesi ihtimali düşük olur. [16] Şekil 2.…”

“…[16] Femur proksimal girişlerinde erişkinlerde piriformis girişinin (Şekil 4) tercih edilmesi ile uzama esnasında oluşabilecek varus deformitesi ihtimali düşük olur. [16] Şekil 2. Kanalın oyulması öncesinde trokanterin tam tipinden giriş ile uzama esnasında trokanterik girişli çivilerde oluşabilecek deformite engellenebilir.…”