It is amazing to discover how little importance has been attached to
narrow lumbar canal syndromes up to now. Though H. VERBIEST gave a very
accurate description in 1949, the neurologist's and neurosurgeon's
preoccupations were mainly focused on discal pathology, disregarding the
problem of an exclusively bony origin in canalar stenosis. A. WACKENHEIM
and E. BABIN have the merit of becoming aware of the impor- tance and
originality of this problem; they organized in the beautiful surround-
ings of the Bischenberg near Strasbourg, a postgraduate course, in which
the most eminent European specialists in this field participated. I am
very honored to have been asked to write the introduction to this mono-
graphy, which contains all the studies reported and commented on during
this meeting. Before considering the problem from the various radiologic
points of view, it is in my opinion indispensable to define the term
"stenosis." We could not do so more accurately than by assuming the
definition proposed by A. WACKENHEIM and E. BABIN and unanimously
confirmed by all those who attented the session.