Flexible non-fusion scoliosis correction systems reduce intervertebral rotation less than rigid implants and allow growth of the spine: a finite element analysis of different features of orthobiom™

Abstract

The orthobiom TM non-fusion scoliosis correction system consists of two longitudinal rods, polyaxial pedicle screws, mobile and fixed connectors and a crossconnector. The mobile connectors can move along and around the rod, thus allowing length adaptation during growth. The aim of this study was to determine the effects of different features of this novel implant on intervertebral rotations, to calculate the movement of the mobile connectors along the rods for different loading cases and to compare the results with those of a rigid implant construct. A finite element analysis was performed using six versions (M1-M6) of a three-dimensional, nonlinear model of a spine ranging from T3 to L2. The models were loaded with pure moments of 7.5 N m in the three main anatomical planes. First, the validated intact model (M1) was studied.

Guided-growth implants in the treatment of early childhood scoliosis – pilot study

“…Examples of such techniques include the Shilla system, Polysegmental Growing Construct and guided-growth implants described in the present paper [9][10][11]. Another example is the dynamic Orthobiom system [12,13]. All authors report high efficacy.…”

“…Do takich roz wią zań na le ży np. sys tem Shil la, Po ly segmen tal Gro wing Con struct czy opi sa ne wsz cze py rosną ce [9][10][11] Opra co wa no ta kże dy na micz ny sys tem Or tho biom [12,13]. Au to rzy po da ją du żą ich skutecz ność.…”

Tribology of flexible and sliding spinal implants: Development of experimental and numerical models

“… and fabricant data). The locking screw (position 1 in Figure A) was modeled as a beam connector element, with all degrees of freedom blocked. The sliding screws (positions 2 and 3 in Figure A) were modeled with a combination of a 3D‐modeled holed rotating ball and a connector to reproduce the behavior of the device (Figure B).…”

Relationships between viscoelastic properties of lumbar intervertebral disc and degeneration grade assessed by MRI

“…Biomechanical models of the spine have been developed to help clinicians either for implant evaluation (Skalli et al, 1993;Wilke et al, 2009;Rohlmann et al, 2008;Adam et al, 2003;Viceconti et al, 2009;Lafage et al, 2007) or for surgery planning (Lafage et al, 2004;Dumas et al, 2005;Lafon et al, 2009;Aubin et al, 2003). Taking into account patient specificity is of paramount importance, both from a geometric and a mechanical point of view.…”