Neck pain but not neurologic disease occurs more frequently in horses with transposition of the ventral lamina from C6 to C7

Abstract

OBJECTIVE To determine reasons for horses to have neck radiographs performed, the incidence of transposition of the ventral lamina of C6 onto C7 (TC67), and the final diagnoses for all horses. Our hypotheses were to find a similar incidence of TC67, as has been previously reported, and an increased incidence of neck pain and dysfunction in horses with TC67. ANIMALS 135 horses. METHODS Retrospective observational study. Medical records of 135 horses with cervical vertebral column radiographs between 2020 and 2022 were assessed. Patient signalment, reasons for radiographs, radiographic findings, and diagnoses were analyzed. The Shapiro-Wilk test was used for normality determination. Nonparametric tests were used to analyze data. RESULTS 20% of horses were diagnosed with TC67. Significantly more horses with TC67 were warmblood horses (63%); TC67 was found in 28% of warmblood horses. There was no significant difference in signalment or whether horses were in work between the groups, although significantly more horses with TC67 performed in English disciplines (71%). No differences in reasons for examination or final diagnoses of neurologic disease, cervical orthopedic disease, or lameness were present between groups. In horses with neck pain, TC67 was significantly more common (31%) than in horses without (18%). CLINICAL RELEVANCE Our results indicated that TC67 occurs more in warmblood horses. In the small group of horses with neck pain reported, TC67 was more commonly seen than in those without. Given the complexity of this region and the paucity of studies exploring neck pain and neck biomechanics, we suggest the need for standardized prospective studies.