ABSTRACT
The reduced inter-pedicular distance is one of the common causes of primary narrowing of the spinal canal. Stenosis of the spinal canal due to decreased inter-pedicular distance is to the best of our knowledge, virtually unexplored so we under took this study of inter-pedicular distance. Eisestein S measured inter-pedicular distance in Caucasoid, Zulu Negroid and Sotho Negroid population which is compared with data of present study. Methods: All measurements were made by using Electronic Digital Vernier Calipers. Transverse diameter of the lumbar spinal canal was measured as the minimum distance between the medial surfaces of the pedicles of a given vertebra (Inter-pedicular distance. Results & Observation: Inter-pedicular distances of lumbar vertebral canal at levels L1 to L5 was measured in dry vertebrae of 63 subjects (32 male, 31 female) from Gujarat of age group 35 to 80 yrs. Mean transverse diameter (Inter-pedicular distance) is minimum at L1 (22.6 mm in male and 21.3 mm in female) and maximum at L5 (27.0 mm in male and 26.4 mm in female) showing a gradual increase from level L1 to L5. The inter-pedicular distance increased steadily from L1 to L5 in all populations in both sexes. The Gujarati population has greater IPDs at all level from L1 to L5 than that of Zulu Negroid and Sotho Negroid. But IPDs in Gujaratis are lower at L1, & L2 in male and L1, L2 & L3 in female and greater at L3, L4 & L5 in male and L4 & L5 in female than that of Caucasoid. Conclusions: A comparison between the present data and the data published data on inter-pedicular distance at lumbar levels of other populations also shows that there are marked differences between the mean values reported for the population of different geographic areas. The present study confirms that there is ethnic as well as racial variation in the size of the lumbar vertebral canal, thus, emphasizing the need to have normal values and ranges for the transverse diameter of the canal for different populations.