Comparative study between ultrasound determination and clinical assessment of the lumbar interspinous level for spinal anesthesia.

BACKGROUND

The aim of the current study is to compare the accuracy of the ultrasound (US) versus clinical assessment for determination of the spinal level, using X-ray as the Gold Standard for control.

METHODS

200 patients were randomized into two equal groups. Patients in the Clinical Group were examined by landmarks to assess the Assumed Clinical Tuffier's Line, and then by fluoroscopy to determine the True Clinical Tuffier's Line. Patients in the Ultrasound Group were examined by the ultrasound to determine the Ultrasound Tuffier's Line. The results of both groups were compared in relation to the plain X-ray, done for each patient, which determined the Radiological Tuffier's Line.

RESULTS

In the Clinical Group, the True Clinical Tuffier's line met the Assumed Tuffier's line in only 12% of the patients. In the remaining patients, wrong leveling ranged from one space above in 80% to 2 spaces above in 7% and in 1% of patients the line was at L2. In the Ultrasound Group, wrong leveling occurred in 22% of patients. The Ultrasound misidentification was less than one level in 17% and one level in 5% of patients. Ultrasound examination had a true limitation of 2% of patients.

CONCLUSION

Ultrasound examination of the spine is recommended in patients planned for spinal anesthesia, as it is superior to clinical assessment in identification of the interspinous levels. This will decrease the hazard of spinal cord trauma.