Objective: The aim of this study was to identify the feasibility of using palpation of the lowest point of the rib in the posterior axillary line to identify the segment of the spine during spinal surgery.
Methods: Three orthopedic surgeons examined 101 patients and determined, by blind palpation, the lowest point of the ribs that could be reached at the posterior axillary line, placed a radiolucent marker, made a plumb line through this point and intersected it at one point C. From this point, a line was made at an angle of 45° to the plumb line and intersected the posterior midline at another point B, where the markers were placed. A posterior anterior lumbar spine X-ray was then taken. Three orthopedic surgeons then identified the spine segment by radiography and assessed the agreement with the spine segment identified by imaging (kappa coefficient).
Results: Point B is most commonly found in the T12 and T11 vertebrae, with an accuracy rate of 86% (87/101).Point C, most commonly at the L3 vertebral body, was 79% (80/101) accurate. The greatest proportion of these was in the upper third of L3. High consistency of results between right and left side on palpation.
Conclusions: In the prone position, clinicians can use this method as a measurement tool with good reliability for palpating the thoracolumbar vertebrae, but the spinal level estimated by palpation may be inadvertently affected by examiner skill and anatomical variation, as well as by issues of individual variation.