Introduction: Most spine surgeons would agree that quality disc space preparation is important to create the optimal environment for interbody fusion. However, there is very little direct information in the literature on how to assess disc space preparation, and direct vision and palpation may be difficult or misleading with minimally invasive approaches. A balloon device (Verify, Spineology) is now commercially available to assist with evaluation of disc space preparation.
Methods: We performed minimally invasive TLIF in 4 patients (5 levels). After initial disc space preparation to a point that was deemed adequate by a senior level resident, the space was assessed with the Verify device inflated with contrast and imaged via fluoroscopy. Further preparation was dictated by the morphology of the balloon inflation.
Results: After initial disc space preparation, the Verify device revealed a space that was determined to be inadequate at all levels performed. Further discectomy and endplate preparation was performed with various instruments, directly guided by the morphology of the inflated balloon. Reassessment of the disc space with the device revealed significant improvements. (Figures of 2 cases included for illustration purposes)
Conclusions: The Verify device can be a valuable tool in evaluating for adequate disc space preparation for interbody fusion, especially in minimally invasive approaches such as TLIF, when a unilateral approach through a small window can limit visual inspection or reliable tactile feedback. In our cases it also served as an excellent tool for resident education.
Patient Care: Improved disc space preparation should lead to improved fusion rates and improved outcomes.
Learning Objectives: Participants should be able to: 1) Understand limitations of disc space preparation assessment in MIS spine surgery, and 2)Describe use of balloon device to assess disc space preparation