A modified muscle-splitting approach to the lumbosacral spine.

A modification of a previously reported extraperitoneal approach to the lumbosacral spine is described. The external oblique muscle is split in line with its fibers. The anterior and posterior layers of the rectus sheath are divided vertically medial to the semilunaris without splitting the internal oblique and underlying transversalis abdominus muscles. This allows an extensile retroperitoneal approach suitable for exposure of both the mid-lumbar and lumbosacral spine. There have been no complications of this approach with its use in over 50 patients undergoing anterior lumbar interbody fusion.