The interpedicular (IP) distance which is the distance measured between the pedicles on frontal / coronal imaging can be narrowed in a number of situations
See reference 1 for an old but interesting article on what the normal interpedicular ditance is according to age, location and gender.
- 1. Hinck VC, Clark WM, Hopkins CE. Normal interpediculate distances (minimum and maximum) in children and adults. Am J Roentgenol Radium Ther Nucl Med. 1966;97 (1): 141-53. Am J Roentgenol Radium Ther Nucl Med (abstract) - Pubmed citation
- 2. Shah K, Astley R, Cameron AH. Thanatophoric dwarfism. J. Med. Genet. 1973;10 (3): 243-52. J. Med. Genet. (link) - Free text at pubmed - Pubmed citation
- 3. Jeong ST, Song HR, Keny SM et-al. MRI study of the lumbar spine in achondroplasia. A morphometric analysis for the evaluation of stenosis of the canal. J Bone Joint Surg Br. 2006;88 (9): 1192-6. doi:10.1302/0301-620X.88B9.17758 - Pubmed citation