Each year, an estimated 18,000 people in the United States experience a spinal cord injury (SCI), causing immense emotional and financial strain for patients and caregivers. Diagnosis and potential recovery for patients relies on extensive clinical examinations and advanced imaging — a time-consuming, costly process that is especially challenging for patients with SCI-related complications.

Now researchers at Johns Hopkins Medicine have developed a novel blood test that has the potential to rapidly predict severity and likelihood of sensory and motor recovery within six months in a cost-effective manner.

“If you have a spinal cord injury, your main question is simple: Am I going to walk again?” says lead study author and neurosurgery chief resident Tej Azad. “With the new blood test, we are trying to bring a precision medicine framework to spinal cord injury with something that tells you about injury severity and can hopefully predict neurological recovery.”

Classically, blood tests have not been considered to offer insights into the spine due to the blood-brain barrier. However, researchers hypothesized that spinal cord injury causes measurable disruptions in the blood-brain barrier that are potentially detectable in a blood test.

To detect such biomarkers of SCI, the researchers built on recent advances in cancer biomarker development, where liquid biopsies of blood detect cell-free DNA (cfDNA) and certain protein levels guide targeted treatments for individual patients while also offering ways to monitor treatment response and disease progression. The investigators call the resulting combination blood test the Spinal Cord Injury Index (SCII), describing it in The Journal of Clinical Investigation.

When compared to the standard American Spinal Injury Association scale used to assess SCI severity based on motor and sensory function, the results of SCII aligned completely with severity of injury and what would be seen on MRI scans and physical evaluations.

“Using blood-based biomarkers for cancer diagnosis and progression has changed the practice of oncology,” says co-senior study author Nicholas Theodore, director of the Johns Hopkins Neurosurgical Spine Center. “Utilizing similar technology, this test is truly an example of personalized medicine in traumatic injury.”