Improving Accuracy in Lower Thoracic Spine Palpation: A New Method Proposal
Purpose/Hypothesis: Thoracic spine manual treatment can improve local muscle activation, reduce pain and help patient recovery if applied with skillful patient selection and technique. Clear methods to identify specific landmarks in the thoracic region lags that of the cervical and lumbar spine. Geelhoed et. al suggests the thoracic transverse processes (TP) is located at the level of the cranial vertebra spinous process (SP) in all but the lower thoracic region. Variability in the lower thoracic region is large and adds to the uncertainty in clear landmark identification with palpation. This leaves a gap in the literature to guide education and practice. The purpose of this study was to examine the reliability and accuracy of a new thoracic spine palpation method in the lower thoracic region.
Number of Subjects: Thirty-six males (n=5) and females (n=31), between 18-40 years of age, who were healthy and without prior spinal surgeries or injuries, participated in this pilot study. Participants were excluded if pregnant or unable to lie prone.
Materials and Methods: After obtaining consent, participants provided demographic and physical activity information, and had their height, weight, and BMI recorded. Participants then underwent palpation and dual x-ray absorptiometry (DXA) scanning while laying prone on the DXA table. Tester 1 (T1) used the 11th rib tip to locate the rib angle and from this, located the spinous process most prominent at the same spinal level. These bony landmarks were connected by a line drawn using an ultraviolet (UV) marker. Tester 2 (T2), blinded to the T1 results, repeated the same palpation and marking process using a different UV marker color. Metal markers were positioned under UV light for T1 and T2 lines, and a DXA image was captured of the region. Categorical data was collected for each tester during image capture and Image-J software used to measure the linear distance from mid-point of 11th SP to the metal mark for each tester. Data was analyzed using was SPSS to provide descriptive measures for T1 and T2 accuracy and Intraclass Correlation Coefficient for intertester reliability.
Results: The accuracy of finding the SP at the same level as the rib angle was 92.86% for both testers. The accuracy of finding the 10th SP from the 11th rib angle (old rule) averaged 7.14%. The accuracy of finding the 11th SP from the 11th rib (new rule) for T1 and T2 averaged 69.05%; however, the accuracy of locating the 11th rib was not precise (T1-16/21; T2-19/21 participants). The average distance from marker to caudal aspect of T11 SP was 16.79mm±18.02 for T1 and 15.01mm±10.35 for T2. Intertester reliability was moderate, ICC (2,1) = 0.422.
Conclusions: The current method taught for SP identification in the lower thoracic region may need modification. Further studies, with a larger sample, are needed to confirm that the SP is at the same vertebral level as the rib angle (and transverse process) in the lower thoracic region.
Clinical Relevance: This study proposes a new method of lower thoracic spine palpation to improve accuracy in regional surface anatomy. Palpation is an essential part of the physical therapy examination. As the spine is a common area of pain and functional limitations, accurate palpation methods can help ensure treatment is targeted for maximum benefit to the patient.