Lumbar neural foramen remodeling by disk herniations.

The discussion of the case report by Dr. Castillo ( 1) of a neural foramen remodeling caused by a sequestered disk fragment prompts me to reply briefly . Dr. Castillo has written that bone remodeling or the neural foramen has not been previously reported in far lateral disk herniations. In an English-speaking paper (2) dealing with extraforaminal lumbar disk herniation (EFLDH), my coauthors and I have shown that 53 % of our series of 47 EFLDH demonstrated a bony avulsion of the vertebral end plate facing the herniation, thus modifying the cortical bone lining the neural foramen. These bony changes correlated well with the usually responsible mechanism of EFLDH, ie, lateral bending and rotation of the trunk. This observation of the frequent avulsion of the bony site of attachment of Sharpey fibers in EFLDH, leading to a remodeling of the neural foramen was presented as an exhibit at the 26th Annual Meeting of the ASNR in Chicago, 1988 (3). From a general point of view, non-American radiologic literature is sometimes not taken into account by American authors, thus leading to some frustration of non-American and especially European authors. I hope that the publication of my letter will attenuate this feeling. J. F. Bonneville Department of Neuroradiology University-Hospital Jean Minjoz 25030 Besancon-France