You are here

Lateral Lumbar Interbody Fusion

Lateral Lumbar Interbody Fusion (LLIF) is a type of minimally invasive lumbar interbody fusion surgery in which access to the spine is gained from the side. Lumbar interbody fusion surgery involves removing the disc material between two vertebrae and replacing it with an implant. The implant restores the disc space to its normal height and provides support and stability while the spine heals. The LLIF approach allows your surgeon to avoid the major neural and vascular structures that surround the spine, reducing the risk to these structures compared to other approaches. The LLIF approach also allows your surgeon to restore proper disc height and spinal alignment and may relieve your pain more effectively than other approaches. However, the size of the incision and the necessary stretching of muscles and nerves during a typical lateral-approach surgery can lead to new and/or increased pain for several weeks or months following surgery.

LLIF Surgery with the Duo™ Expandable Interbody Fusion System


The Duo system is an anatomy-conserving approach that offers the latest advancements in lateral lumbar interbody fusion surgery and has demonstrated significant success in reducing pain and restoring function after surgery. Its deployable implant design allows placement in the disc space through a small tube. Once in the disc space, the implant is expanded to its final shape and size to provide spinal support and stability that may relieve your pain.

Click here to view the brochure: 

Click to view Duo Patient Brochure 


Duo’s unique implant and tube design decreases the incision size and reduces the access required to perform the surgery to less than half of that required for traditional lateral interbody fusion systems.1 This decreased stress on surrounding nerves and muscle may significantly reduce or eliminate the pain and discomfort you may experience following the surgery. 

Retraction requirements for Duo Ti implant verses traditional lateral surgery implant

Amount of retraction required for a Duo procedure (left) compared to a traditional LLIF procedure (right). Note that the Duo procedure requires less stretching of the nerves (yellow) and muscles (red).

Duo implant shown in the disc space

Fast Recovery

Following a Duo procedure, you will be up and walking the same day or the following day, and you will likely be able to go home within a day or two. Recovery will start immediately and be an ongoing process. Working closely with a physical therapist on correct movement and exercises and following your physician's instructions will aid your recovery. Most patients report significant pain relief immediately after surgery, and you may continue to show improvements in pain and function for up to a year after your surgery.

Pain Relief with Duo Expandable Interbody Fusion System

The Duo LLIF procedure has demonstrated significant improvement in patient low back and leg pain.1

According to an ongoing 200-patient study:



Patient Example

The example below includes images of an actual patient’s spine before and after spine surgery with the Duo Expandable Interbody Fusion System. This patient was a 51-year-old male who was diagnosed with Grade I Spondylolisthesis and had not previously had spine surgery. Prior to surgery, he reported experiencing substantial pain in his low back, both legs, and right hip and buttock. He could not walk more than 100 yards. 

Spine xray before and after Duo surgery. Disc space height is restored and spondylolisthesis corrected.

Six weeks after surgery, he could walk a quarter mile and had resumed normal activities. By his three-month follow-up visit, he had started physical therapy and was able to walk more than a mile. His hip and buttock pain were eliminated, and his low back and leg pain were greatly reduced. His recovery continued through his 24-month follow-up visit and no additional treatment was required.* 

*Individual patient results may vary


Is the Duo procedure right for you?

If you require surgery, your surgeon may determine that a Duo LLIF procedure is a good option for you. Conditions that can be treated with the Duo Expandable Interbody Fusion System include:

  • Degenerated discs of the lumbar spine that cause pain in the lower back and/or legs
  • Spondylolisthesis – Grade I (one vertebra has slipped forward over another)


Having surgery is an important decision, so speak with your physician about the best treatment option for your specific condition.

Doctor talking to patient


1 Nunley P, et al. Multi-center, prospective outcomes following lateral lumbar interbody fusion: successful function at 12 months.  International Society for the Advancement of Spine Surgery (ISASS) 2021. Miami, FL. 2021 May 13-15.