Accessory foramina transversaria in the cervical spine: variations and their clinical significance

ABSTRACT

To assess number, type and diameter of accessory foramen transversarium [AFT] in the cervical spine. Descriptive observational study. Anatomy department, Sheikh Zayed Medical College, Rahim Yar Khan and Wah Medical College, Wah Cantt., district Rawalpindi. Duration of this study was two years. The study included 45 sets of cervical spine [315 human cervical vertebrae]. Direct measurements were taken with vernier calipers sensitive to 0.01 mm. Number, type and diameter of AFTs were assessed, recorded and analysed. Most of the AFTs were observed in the lower cervical vertebrae; C4, C5 and C6 showed AFTs present as 13.33%, 35.55% and 51.11%. AFTs were 33 on right side and 46 on left side. AFT type I was the most common present in 52 vertebrae [16.50%]. The mean AFT diameter on right side was 2.13 +/- 0.53 mm and on left side it was 2.29 +/- 0.73 mm. The incidence of AFT was higher in our population and AFTs were more in the lower cervical vertebrae. Studying the number, type and diameter of AFTs is of clinical significance in understanding the possible neurovascular variation and their course. Such variations should always be suspected when examining transverse processes having an unusual pattern of foramina transversaria