Lateral Lumbar Interbody Fusion: A New and Useful Tool for the Spine Surgeon

By R. Douglas Orr, MD

One of the more interesting and useful developments in spine surgery technologies over the past decade has been the emergence of minimal access lateral lumbar interbody fusion (LLIF). Commonly known by the trademarked names XLIFTM and DLIFTM among others, this technology allows surgeons to perform anterior interbody fusions through small incisions (2-4 cm) using a tubular retractor.

An online search of the term XLIF yields more than 150,000 hits, demonstrating a great deal of interest in the technology, presumably by both medical professionals and patients. Minimal access LLIF, which uses a muscle-sparing approach, has been shown to decrease hospital stays and shorten recovery times compared with LLIF performed as an open procedure.1 Although LLIF was originally developed for degenerative pathology, the indications for minimal access LLIF have increased, and it has become an important tool in lumbar spine deformity surgery.2

Rewards and potential risks

LLIF technology allows placement of large interbody implants and can be used to restore alignment of the spine in both the frontal and sagittal planes.2 In most studies, LLIF has demonstrated high fusion rates2,3 and relatively low complication rates.

As with many new technologies, there was initially a lot of enthusiasm for this approach and very rapid growth in its usage. However, as the technology became more widespread, increased problems were reported, leading to some pullback. Foremost among these issues was the incidence of transient nerve palsies. This is particularly true in surgery done at the L4/5 level, where rates of up to 30 percent have been reported.4

The access corridor for this approach is made through the bulk of the psoas muscle. The nerves of the lumbosacral plexus exit the spine at the foramen and then penetrate and traverse the psoas muscle to coalesce into the nerve of the plexus anterior to the psoas. As a result, the procedure is performed using stimulated EMG monitoring in an attempt to avoid injury to the nerves.

Due to a variety of anatomic constraints and variations, the L3 nerve root is at particular risk when operating at the L4/5 level. Consequently, this author no longer uses this technique at the L4/5 level, and instead employs the anterior lumbar interbody fusion (ALIF) approach. Many others still use minimal access LLIF at the L4/5 level.

A very useful tool, but not a panacea

Many of its proponents seem to regard LLIF as the solution to most spine problems. A more reasoned viewpoint would be that LLIF has a role in the treatment of many pathologies and can be a very useful tool — but as part of a much larger toolbox. It has both advantages and disadvantages compared with other techniques.

No single technique is the answer to every problem. When a surgeon recommends a particular form of treatment, patients should be encouraged by their referring physician to ask why that technique is preferred over other available options.

LLIF case examples

The following images illustrate LLIF as used in two patients:

Patient A is a 78-year-old male who had debilitating left leg pain treated with LLIF and percutaneous instrumentation, with complete resolution of pain. Top two images are preoperative AP and lateral X-rays showing rotatory subluxation of L2-3. Bottom two images are three-month postoperative X-rays showing restoration of alignment.

Patient B is a 38-year-old male with a history of back pain due to thoracolumbar kyphoscoliosis. Intraoperative X-rays show the extent of correction that can be achieved using LLIF technique through a single 2 cm incision. The second posterior stage was performed the same day. Bottom two images are from two years postsurgery — three months after the patient received his second-degree black belt in taekwondo.

References

1. Barbagallo GM, Albanese V, Raich AL, Dettori JR, Sherry N, Balsano M. Lumbar lateral interbody fusion (LLIF): Comparative effectiveness and safety versus PLIF/TLIF and predictive factors affecting LLIF outcome. Evid Based Spine Care J. 2014;5(1):28-37.
2. Haque RM, Mundis GM Jr, Ahmed Y, et al; for the International Spine Study Group. Comparison of radiographic results after minimally invasive, hybrid, and open surgery for adult spinal deformity: A multicenter study of 184 patients. Neurosurg Focus. 2014;36(5):E13.
3. Berjano P, Langella F, Damilano M, et al. Fusion rate following extreme lateral lumbar interbody fusion. Eur Spine J. 2015;24(Suppl 3):369-371.
4. Arnold PM, Anderson KK, McGuire RA Jr. The lateral transpsoas approach to the lumbar and thoracic spine: A review. Surg Neurol Int. 2012;3(Suppl3):S198-S215.

Dr. Orr is a spine surgeon in the Center for Spine Health. He can be reached at orrd@ccf.org or 216.363.2410.