Assessment of Spinal Motion in Young Adults (15 to 26 Years of Age) Without Spine Deformity Using Inertial Sensor and Manual Measurements

Abstract

Introduction: The evaluation of spinal range of motion is paramount in the context of spinal disorders, especially considering emerging surgical techniques focused on motion preservation and circumventing spinal fusion. Manual measurement techniques, which utilize a goniometer and tape measure, demand proficiency to accurately assess spinal motion. This becomes further complicated in patients with spinal deformities. Inertial sensors emerge as a potential clinical solution. By assessing electronic inertial sensor performance in capturing thoracolumbar spinal range of motion, this study evaluates the level of association observed between the range of motion measurements captured by manual and sensor methods. Methods: Participants included 19 healthy young adults (74% female, average age 20 years [range 15-26]) without spinal conditions. Each performed a series of manual spinal motion evaluations quantified using a standard goniometer and a tape measure. Participants repeated the motions with an electronic inertial sensor attached to their C7 spinous process. Each manual and electronic motion sequence was performed three times. Data were analyzed with a Pearson’s correlation to assess congruence between the datasets, and a paired t-test compared the mean values between the two groups to examine the two motion measurement methodologies. Results: Association between the different planes of motion for manual and electronic repeated clinical motions were moderate (r=0.44) to strong (r=0.70). Manual measurements showed similar levels of variation to that of the electronic measurements. Upon comparing the manual and electronic measurement sets through a paired t-test, the mean values exhibited no statistically significant differences. Conclusion: The electronic motion measurements were congruent with manual measurements based on the correlation values and t-tests presented. Thus, inertial sensors can approximate the measurements of manual methods in assessing spinal range of motion. This demonstrates the potential for clinical adaptation of these sensors into spine centers to objectively assess patient outcomes in spinal motion preserved surgeries.