Ultrasonography as an intraoperative tool for localization of the anatomical level in lumbosacral spine surgeries

Aims and Objectives: The aims and objectives of the study are to find the effectiveness of ultrasound as a pre-operative adjunct to localize the anatomical intervertebral level of interest and study its accuracy by comparing it with the gold standard intra-operative fluoroscopy and to study factors affecting localization of anatomical vertebral level by ultrasound. Methods: This was a prospective study conducted in the Department of Neurology Department of Neurosurgery and Neuroimaging and Interventional Radiology, NIMHANS Hospital, Bengaluru, over a period of 1 year. 50 cases of lumbosacral degenerative diseases were included in this study on the basis of pre-defined inclusion and exclusion criteria. All patients underwent ultrasonography of the lumbosacral spine followed by pre-operative X-ray of the lumbosacral spine using the C-ARM. The accuracy of good localization of the desired level of the lumbosacral spine by ultrasound as compared to X-ray was determined. p<0.05 was taken as statistically significant. Results: There were 22 (44%) males and 28 (56%) females with a M: F ratio of 1:1.27. The mean age was 46.7±13.5 years. 46 (92%) cases were diagnosed with prolapsed intervertebral disc (PIVD) and 4 (8%) cases with Grade II spondylolisthesis radiologically. Good localization which constitutes exact localization, close upper, and close lower localization added up to 82% of the cases (41/50) and the rest 18% were tagged as poor localization (9/50). The accuracy of good localization in both the groups of PIVD and spondylolisthesis (listhesis) was 82.6% and 75%, respectively. Conclusion: Ultrasound can be used as an exceptionally good and accurate method of localizing the anatomical intervertebral level for patients undergoing various lumbosacral spinal surgeries.