# X-ray Visualized Interbody Spacer Indicating Biomechanical Load (X-VISIBL) Fusion Device

> **NIH NIH R41** · SPINEFRONTIER, INC. · 2021 · $252,127

## Abstract

Abstract
 Spine disorders, primarily caused by degenerative spine conditions, deformity, tumors, and trauma, affect
approximately half of the population aged over 40. To address these disorders, over 457,000 spine fusions
were performed in the US in 2011 (6% annual growth), including about 290,000 anterior cervical discectomy
and fusions (ACDF). ACDF surgery removes 1-4 intervertebral discs and replaces them with interbody spacers
filled with bone graft. This distracts and decompress the nerve roots while fusing the adjacent vertebrae.
Postoperatively, it is critical to recognize when the vertebrae have fused, an outcome that determines safe
return to activity; conversely, delayed fusion may indicate need for additional interventions (e.g., prolonged
collar usage, modified physical therapy, electrical stimulation, and injections such as rhPTH). Improper
management can lead to poor outcomes, worse pain, surgical revision and neurological deficits. Unfortunately,
patients heal at rates that vary greatly, and some patients will not heal properly with 7% needing costly revision
surgery ($123,000 hospital charges).
 We propose to develop an X-ray Visible Interbody Spacer Indicating Biomechanical Load (X-VISIBL) fusion
device to assist clinicians in tracking and detecting bony fusion. If successful, this project will validate a simple
indicator that reports load on the device to assess fusion of the adjacent bones. Measurements are made
using flexion/extension radiography which is already routinely used in patient follow-up but is currently
insufficiently sensitive to detect delayed fusion and non-union. Monitoring implant load will provide the patient
and medical team critical information to select early targeted interventions including prolonged brace or collar
usage, modified physical therapy and return-to-work protocols, ultrasound or electrical stimulation, medications
or injections such as rhPTH, and inform long term care to avoid device failure and associated pain, disability
and reoperations.
 This Phase I Small Business Technology Transfer project aims to assess technical feasibility for a load
indicating cervical interbody spacer. The approach is innovative in providing a sensor to clearly measure load
during fusion with X-ray readout that is already part of the standard of care. To show feasibility, we must
develop prototypes with mechanical properties that allow/encourage fusion (especially stiffness and yield) and
the precision to detect physiological load changes during fusion. This will be accomplished with computer
simulations, mechanical prototype fabrication and testing, and radiography in cadaveric models.
 The research is relevant to public health because, it provides an objective non-invasive means to assess
biomechanical fusion and assist physicians prescribing rehabilitation protocols and adjunctive therapies.

## Key facts

- **NIH application ID:** 10157213
- **Project number:** 1R41AR078137-01A1
- **Recipient organization:** SPINEFRONTIER, INC.
- **Principal Investigator:** John David DesJardins
- **Activity code:** R41 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2021
- **Award amount:** $252,127
- **Award type:** 1
- **Project period:** 2021-01-18 → 2022-09-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10157213

## Citation

> US National Institutes of Health, RePORTER application 10157213, X-ray Visualized Interbody Spacer Indicating Biomechanical Load (X-VISIBL) Fusion Device (1R41AR078137-01A1). Retrieved via AI Analytics 2026-05-26 from https://api.ai-analytics.org/grant/nih/10157213. Licensed CC0.

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