Surgical anatomy of the diaphragm in the anterolateral approach to the spine: a cadaveric study.

Study Design: Laboratory cadaveric study. Objective: To delineate the pertinent surgical anatomy of the diaphragm during access to the anterolateral thoracolumbar junction. Summary of Background Data: The general anatomy of the thoracic diaphragm is well described. The specific surgical anatomy as it pertains to the lateral and thoracoabdominal approaches to the thoracolumbar junction is not well described. Methods: Dissections were performed on adult fresh cadaveric specimens. Special attention was paid to the diaphragmatic attachments to the lower rib cage and to the spinal thoracolumbar junction. Results: The pertinent diaphragmatic attachments to the rib cage are at the 11th and 12th ribs. Whether the diaphragm is incised or mobilized ventrally, the pertinent spinal attachments are the lateral and medial arcuate ligaments. Identifying and sectioning these structures allows for direct access to the thoracolumbar junction, particularly the L1 vertebral body. Conclusions: An understanding of the diaphragmatic-costal and diaphragmatic-spinal attachments is key for the safe and effective implementation of diaphragm mobilization during the lateral and thoracoabdominal approaches to the spine.