Introduction: Intraoperative localization of the correct spinal level remains an ongoing challenge for spine surgeons and pre-operative or intra-operative fluoroscopy remains the mainstay in the majority of centres. Upper lumber and thoracic spine localization can be especially error prone as one must count up or down from known levels.
Methods: To reduce counting errors, we use a patterned marked radio-opaque metal ruler secured to the side or back of the patient to ‘label’ vertebral levels during counting. This ruler has unique cut-outs at regular intervals that provide a backdrop during fluoroscopy that are correlated to vertebral bodies.
Results: This versatile technique has been used in both anterior-posterior and lateral fluoroscopy for localization in the cervical, thoracic, and lumbar spine. Perhaps the most useful application is in localization of the upper thoracic spine in obese patients where soft-tissue density limits the visualization of the vertebral bodies. The marking ruler provides a stable reference point to reliably count levels and non-invasively mark the operative level for re-checking.
Conclusions: We present a simple and inexpensive method for increasing accuracy in the intra-operative localization of spinal segments. We believe this method increases surgeon confidence in the correct spinal level and reduces errors in localization during fluoroscopic counting.
Patient Care: By providing a simple and straight forward method to identify count vertebral levels intraoperatively to reduce counting errors and wrong level surgery.
Learning Objectives: By the conclusion of this session, participants should be able to:
1) Understand the use of this novel ruler in counting vertebral levels.
2) Apply this simple technique for intraoperative localization.