Intra-rater reliability of determining positions of cervical spinous processes and measuring their relative distances

Objectives A reliable detection of bony landmarks of the spine is necessary in order to determine rigid bodies and to reduce the variability of marker placement in a movement laboratory setting. In a first study on the thoracic and lumbar spine, we demonstrated that placing markers on their relative positions between two major landmarks was superior to palpation of specific bony landmarks. The aims of this study were to examine the intra-rater reliability when palpating for spinous processes (SPs) of the second (C2) and seventh cervical vertebrae (C7), to determine the distances between C2 and C7 and the relative position of C7 along the length between C2 and the posterior superior iliac spine (PSIS) level.