Palpation accuracy of thoracolumbar spinous processes using T13 and the 13th pair of ribs as landmarks in dogs

There is a lack of studies of methods for the clinical assessment of spinal orientation in dogs. Our objective was to determine the accuracy of the identification of the thoracolumbar spinous process by palpation using T13 and the associated pair of ribs. We wished to assess whether spinal localization can be accurately determined by this method and whether the accuracy depends on examiner experience and variables linked to dog characteristics. Four examiners identified different thoracolumbar spinous processes in 120 dogs using one-hand palpation of the T13 spinous process and the 13th pair of ribs. The spinous process (T13, L1 or L2) was marked with a hypodermic needle and a laterolateral radiograph or a postoperative ventrodorsal radiograph of the thoracolumbar spine was performed to confirm the vertebral determination. The relationship of accuracy to length of the examiner's fingers, training level and the body condition score of the dogs (BCS) were determined. Identification was correct in 87.5% of the cases. All the defined vertebrae were identified with no difference in accuracy (p=0.89). There was no difference between individual examiners (p=0.26). The size of hand had no influence (p=0.13). There was a statistically signifi cant association between the palpatory accuracy and a BCS of 5 (OR=21.11; 95% CI 1.08 - 5.02; p=0.003), as well as with the factor of an experienced examiner in dogs with a BCS of 5 (OR=5.76; 95% CI 0.14 - 3.36; p=0.019). Considering the whole study population, the palpatory accuracy of detecting the thoracolumbar spinous process using T13 and the 13th pair of ribs seems to be independent of examiner experience. In neurosurgical cases the authors recommend confirming the findings by means of diagnostic imaging.