Patient-specific spinal model may predict the effect of disc implants

As people get older, the intervertebral discs in their spine tend to deteriorate, some of which end up being surgically replaced with implants. A new patient-specific spinal model, however, could help determine how successful such surgery will be.

Led by Florida Atlantic University’s Prof. Erik Engeberg and the Marcus Neuroscience Institute’s Dr. Frank Vrionis, a team of scientists started by obtaining a CT scan of a patient’s spine. That scan was then used to create a 3D computer model, which was in turn utilized to produce a 3D-printed articulated model of one section of the spine.

The polymer model was printed with a cervical disc implant already in place, between two of the vertebrae. Also incorporated into the model was an array of soft magnetic sensors, made of an inexpensive mixture of silicone and magnetic powder.

A robotic arm was subsequently used to flex and extend the spinal replica, simulating five different real-life spinal postures (center, mid-flexion, flexion, mid-extension and extension). As it did so, the sensors monitored the manner in which the added implant was causing stress to be distributed throughout the spine.

The setup was found to be 100 percent accurate at replicating the effects that the postures would have on the real spine, with the addition of the implanted disc.

It is now hoped that once developed further, the technology could be used to determine what sort of implant and/or surgical technique would work best, before the surgery is actually performed. Additionally, simulations performed with the model could provide patients with a better idea of what sort of activities it’s OK to engage in while recuperating from the surgery.

“This new approach has a powerful potential to enable surgeons to preview and compare the effects of different surgical interventions in a patient-specific manner using robotically actuated spine twins,” said Vrionis. “Moreover, the novel system could help in determining whether a constrained, semi-constrained, or unconstrained device could be the best fit or even a fusion device.”

A paper on the research was recently published in the journal Sensors.

Source: Florida Atlantic University

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