On the Accuracy of Cervicothoracic Vertebral Level Determination by Palpation of Spinous Processes

Lee, Young Bok; Kim, Soon Yul; Park, Jong Taek; Han, Yi Kyeong; Yoon, Kyung Bong

Abstract

BACKGROUND: The C7-T1 interspinous space is commonly chosen for cervical epidural blockade, usually regarding the vertebral prominence as C7. But determining the vertebral prominence itself is confusing and unreliable because of individual variances. For this reason, we decided to look into the accuracy of estimating segmental level from palpating the surface anatomy.
METHODS
1. When the neck was flexed in the sitting position, cervical spinous processes were palpated and the first and most prominent spinous processes were marked. 2. In the same position, the estimated location of the C7 vertebral spinous process was marked, counting cephalads from the lower end of scapular (known to be at the T7 level, customarily). 3. By using the radiologic imaging method, actual cervical vertebral levels were confirmed and the results were compared with the vertebral spinous processes palpated and marked by the above methods.
RESULTS
The first prominent spinous process was most commonly the C6 spinous process in both male and female subjects. The most prominent spinous processes palpated were C7 in males and C6 in females in the largest number of subjects. Estimates from the lower end of the scapular were correct in only 47.2% of cases.
CONCLUSIONS
Because of considerable individual variances, estimates from the surface references can be incorrect in many circumstances, and radiologic imaging methods are suggested for the correct determination of the cervical vertebral levels.