Study Design. Image data of the male and female cadavers from the Visible H
uman Project were visualized and quantified.
Objective. To clarify the anatomy of the lumbar part of the human lumbar er
ector spinae muscles.
Summary of Background Data. Recent studies have shown discrepancies in the
description of the anatomy of the lumbar part of the lumbar erector spinae.
The main differences concern whether lumbar fascicles of iliocostalis lumb
orum exist and whether the lumbar fascicles have direct attachments to the
ilium or attach via the erector spinae aponeurosis. With the Visible Human
Project from the U,S. National Library of Medicine, a new powerful basis fo
r anatomic investigation has become available.
Methods. Software was produced to visualize sections oriented in any direct
ion and with maximum resolution of the Visible Human male and female. Three
-dimensional coordinates of anatomic structures in the image space could be
marked in the cross-sectional images. The geometry and the physiologic cro
ss-sectional areas of the erector spinae fascicles of lumbar origin were th
us derived.
Results and Conclusions. The study supports a classification of the lateral
fascicles of the lumbar part of the lumbar erector spinae as part of ilioc
ostalis lumborum. In both the male and the female, a large part of the erec
tor spinae fibers of lumbar origin attached to the erector spinae aponeuros
is. These results are of importance for biomechanical analysis of force tra
nsmission in the lumbar spine.