Resorbable plating system stabilizes tissue-engineered intervertebral discs implanted ex vivo in canine cervical...

Area of Science:

• Biomaterials Engineering
• Spine Biomechanics
• Regenerative Medicine

Background:

• Tissue-engineered intervertebral discs (TE-IVDs) show promise for treating disc degeneration but face challenges with implant displacement.
• Previous in vivo studies demonstrated good cell viability and tissue integration but significant implant migration.

Purpose of the Study:

• To evaluate the impact of a resorbable plating system on the biomechanical stability and stiffness of TE-IVD implants.
• To assess the ability of the plating system to prevent implant displacement under axial compression.

Main Methods:

• Canine cervical spine motion segments (C2/C3 to C5/C6) were tested in four conditions: intact (CTRL), discectomy (Dx), TE-IVD only (PLATE-), and TE-IVD with a resorbable plate (PLATE+).
• Axial compression was applied to assess motion segment stiffness and implant stability at 50% compressive strain.

Main Results:

• The PLATE+ group fully restored endplate separation and exhibited significantly higher compressive stiffness compared to the PLATE- group.
• Plated segments restored over 25% of intact motion segment stiffness and prevented implant extrusion.
• Plate attachment demonstrated a more significant effect in preventing extrusion at C3/C4 compared to C5/C6 levels.

Conclusions:

• Resorbable plating enhances the retention and stability of TE-IVDs within the disc space.
• This stabilization is crucial for allowing TE-IVDs to integrate with host tissue and restore native spine biomechanics.
• The findings support the use of stabilization systems to improve the clinical viability of TE-IVD total disc replacement.