Risk of Implant Loosening After Cyclic Loading of Fusionless Growth Modulation Techniques: Nitinol Staples Versus Flexible Tether

  title={Risk of Implant Loosening After Cyclic Loading of Fusionless Growth Modulation Techniques: Nitinol Staples Versus Flexible Tether},
  author={Burt Yaszay and Joshua D Doan and Kevin C. Parvaresh and Christine L. Farnsworth},
Study Design. Biomechanical evaluation using porcine spines. Objective. Compare the fixation strength of two currently used fusionless adolescent idiopathic scoliosis correction techniques following cyclic loading using porcine spines. Summary of Background Data. The ability of fusionless implants to control or correct scoliosis in a growing patient requires such implants to maintain spinal fixation. Because they cross the disc, motion may weaken fixation over time. Methods. Eight pig spines… 
3 Citations
Does Vertebral Body Tethering Cause Disc and Facet Joint Degeneration? A Preliminary MRI Study with Minimum 2-years Follow-up.
Intermediate discs and facet joints were preserved after growth modulation with VBT surgery at a mean of 29 months of follow-up, and the effects of relative stabilization and altered biomechanical loads were warranted.
Fracture Fixation Using Shape-Memory (Ninitol) Staples.
SMA staples have inherent compressive properties that create a stable fracture environment that promotes primary bone healing and are used successfully for osteotomies, arthrodesis, and fracture fixation.
Antibacterial activity and osseointegration of silver-coated poly(ether ether ketone) prepared using the polydopamine-assisted deposition technique.
  • C. Gao, Y. Wang, +7 authors B. Li
  • Materials Science, Medicine
    Journal of materials chemistry. B
  • 2017
The findings from this study indicate that the facilely prepared PEEK-PDA-Ag substrates possess considerable biocompatibility and antibacterial properties, permitting their potential use as a promising orthopaedic implant material.


A Biomechanical Assessment of Thoracic Spine Stapling
The data indicate that staple fixation does not result in consistently elevated adjacent segment motion, which implies that staples are able to significantly restrict motion while not achieving motion reductions that one would achieve with fusion-promoting instrumentation.
A biomechanical investigation of vertebral staples for fusionless scoliosis correction.
Investigating the biomechanical consequences of staple insertion in the anterior thoracic spine using in vitro experiments on an immature bovine model found it is possible that growth modulation following staple insertion is due to tissue damage rather than sustained mechanical compression of the motion segment.
Effects of intraoperative tensioning of an anterolateral spinal tether on spinal growth modulation in a porcine model.
Tether pretensioning created immediate deformity without effecting ultimate vertebral or disc deformity creation in mini-pigs in an immature porcine model.
Spinal Growth Modulation With an Anterolateral Flexible Tether in an Immature Bovine Model: Disc Health and Motion Preservation
Although changes in proteoglycan synthesis, collagen type distribution, and disc thickness were observed, the tethered discs had similar water content to control discs and did not demonstrate gross morphologic signs of degeneration.
Asymmetrical Flexible Tethering of Spine Growth in an Immature Bovine Model
It is postulated that a mechanical tether to the anterior and lateral growth of the spine in a growing child with scoliosis may allow spontaneous correction of sagittal and coronal plane deformity obviating the need for an arthrodesis.
Unilateral and Bilateral Sacropelvic Fixation Result in Similar Construct Biomechanics
Study Design. In vitro biomechanical investigation of lumbosacropelvic spinal instrumentation. Objective. Determine whether unilateral iliac fixation, with or without an L6 to S1 interbody graft,
The modulation of spinal growth with nitinol intervertebral stapling in an established swine model
Six months of nitinol intervertebral stapling created a mild coronal and sagittal deformity associated with reduced vertebral and disc height, and increased coronal vertebraland sagittal disc wedging.
Spinal growth modulation with use of a tether in an immature porcine model.
In this porcine model, mechanical tethering during growth altered spinal morphology in the coronal and sagittal planes, leading to vertebral and disc wedging proportional to the duration of tethering.
Multilevel Spinal Growth Modulation With an Anterolateral Flexible Tether in an Immature Bovine Model
Given adequate bony fixation, a flexible lateral spinal tether can affect growth modulation and may serve as a future fusionless method of correction in a growing patient with scoliosis.
Comparative Analysis of Pedicle Screw Versus Hybrid Instrumentation in Posterior Spinal Fusion of Adolescent Idiopathic Scoliosis
Pedicle screw instrumentation offers a significantly better major curve correction and postoperative pulmonary function values without neurologic problems compared with hybrid constructs in adolescent idiopathic scoliosis treated at a single institution.