Spin-off

SpineWelding

A pedicle screw that anchors itself, in bone too soft to hold one

Visit the company

Challenge

Spinal fusion depends on pedicle screws holding in the vertebra. In osteoporotic or otherwise poor bone they do not: the screw toggles, loosens and pulls out, and the construct fails. The established answer is bone cement - inject PMMA around the screw and hope. Cement is permanent, it cures hot next to the spinal cord, it can leak into the vertebral veins, and it makes revision surgery considerably worse. Surgeons were choosing between a screw that might loosen and a fix they could not undo.

Solution

SpineWelding licensed BoneWelding® - the WoodWelding platform Creaholic invented - and built it into a screw. The Elaris® screw is cannulated and fenestrated; a resorbable PLDLLA pin is placed inside it and a motorised piezo handpiece drives a sonotrode down the cannulation. Ultrasound liquefies the polymer, the motor pushes it out through the fenestrations, and it flows into the surrounding cancellous bone and sets. The bond is immediate, it can be repeated up to three times in the same screw if more anchorage is wanted, and the same handpiece melts the interface again if the screw ever has to come out.

The Elaris® system: the screw, the sonotrode and the motorised piezo handpiece

Results

The Elaris® I Pedicle Screw System holds FDA 510(k) clearance (K183091); Elaris® II, which adds multiple polymer enhancement, is pending. SpineWelding's own cadaveric testing puts residual pull-out strength after loosening at roughly three times a plain screw, and toggling resistance above both a plain screw and a competitor screw augmented with cement. The polymer is fully bioresorbable - poly-L-lactide-co-D,L-lactide, metabolised to water and CO₂ - so nothing permanent is left behind where cement would have been.

  • Residual pull-out strength in cadaveric bone after loosening, against a plain screw
  • Toggling resistance, against a plain screw and a cemented competitor screw

At a glance

Origin
BoneWelding® technology, licensed from WoodWelding SA - a Creaholic spin-off
Products
Elaris® I Pedicle Screw System · Elaris® II Multiple Polymer Enhancement
Regulatory
FDA 510(k) K183091 (Elaris® I) · patents US6921264, US8974506
Material
PLDLLA - fully resorbable, metabolised to H₂O and CO₂

Want to develop a technology platform, too?

Are you inspired by this case study and interested in discussing a similar challenge?
If so, then reach out to one of our experts!

Get in touch

Other companies that started here