Extreme lateral interbody fusion (XLIF) and direct lateral interbody fusion (DLIF) are novel minimally invasive transpsoas approaches to the lumbar spine for performing fusions. Advantages of DLIF include easier technique, faster recovery, minimal complication, high fusion rate, and possibility of achieving better alignment. Many previous reports have evaluated outcomes of DLIF. The authors described surgical procedure of DLIF and reviewed clinical outcomes, radiological outcomes, and complications from various literatures. In conclusion, the DLIF seems to be a valuable minimally invasive surgical tool for the fusion in patients with various diseases, including degenerative disc disease, instability, stenosis, scoliosis, tumor, infection, and adjacent segment degeneration.
Intraoperative blood loss volume increases due to soft tissue injury or excessive traction generated by extensive approach including posterior fusion or posterior lumbar interbody fusion, leading to the occurrence of complication and delay in postoperative recovery, On the other hand, MI-TLIF minimizes injuries in soft tissue and surrounding muscle by approaching between multifidus muscles and longissimus dorsi after separating them, and reaching intervertebral disc from lateral vertebral foramen. The advantages of this surgical procedure are minimization of muscle or soft tissue injuries incurred by lateral approach, reduction of surgically related muscle damage, and decrease of postoperative blood loss. However, The size of cages are limited by transforaminal approach in MI-TLIF, eventually it could be difficult to maintain the correction of deformity(disc height, segmental and lumbar lordosis).
Recently, DLIF(Direct lateral interbody fusion) is developed to improve the disadvantages of TLIF. DLIF allows to insert larger cage than TLIF, as a result larger cage have a advantage to maintain correction of disc height and lordosis because it can support both apophyseal rings of endplates.
However, Transpsoas approach is essential for DLIF, so we need to understand the anatomy lumbosacral plexus in psoas, because nerve injury during the transpsoas approach is the most common and potentially the most devastating complication of the DLIF procedure. And many authors reported that various frequency of nerve injury according to surgeon’s skill. Therefore, surgeon’s skill and accurate understanding about the procedure are important factors to prevent the complications of DLIF.