For years, spine surgeons encountered multiple challenges using static interbody cages in procedures. The desire to minimize these challenges led to the development of expandable interbody cages.
To better understand the advantages of expandable interbody cages — and specifically the advantages of the Catalyft™ PL expandable interbody device — Becker’s Spine Review recently spoke with two leading spine surgeons who have experience using the Catalyft™ PL expandable interbody device:
- Christopher Holland, MD, PhD, neurosurgeon, Carolina Neurosurgery & Spine Associates in Concord, N.C.
- Sharad Rajpal, MD, board-certified neurosurgeon, Boulder (Colorado) Neurosurgical and Spine Associates
Dr. Holland and Dr. Rajpal responded to a series of questions about their experiences with the Catalyft™ PL expandable interbody device. Both of their responses are summarized below, with minor edits for clarification.
Question: The development of expandable interbody cages arose due to common challenges associated with static interbody cages when restoring lordosis/ sagittal alignment. How does the Catalyft™ PL expandable interbody device help minimize those common challenges?
Dr. Christopher Holland: Historically, the inability to improve lordosis had been a major criticism of MIS TLIF procedures. The Catalyft™ PL expandable interbody device can securely expand to up to 22 degrees of lordosis in a continuous fashion while auto-locking at any position. The Catalyft™ PL expandable interbody device provides the lordotic expansion necessary to help us achieve desired improvements in segmental and global lumbar lordosis, and therefore, overall sagittal alignment.
Dr. Sharad Rajpal: Placing an interbody cage from a posterior approach has unique challenges when compared to its anterior and lateral cage counterparts. The biggest concerns for spine surgeons when approaching the spine posteriorly include using an interbody cage that is small enough to be inserted without causing injury to the dura and/or neural elements, but is large enough to “fill” the interbody space, to promote bony fusion and to restore or maintain lordosis/sagittal alignment.
With the design of the expandable Catalyft™ PL expandable interbody device, I feel the ease of insertion comes from the matching footprint of the cage true to the size of the trials and the nicely designed anterior beveled tip. Once deployed within the disc space, the Catalyft™ PL40 cage has a longer length, compared to Catalyft™ PL expandable interbody device, and a continuous angular adjustment up to 22 degrees that allows the maintenance and restoration of lordosis and sagittal alignment.
Q: The design of the Catalyft™ PL40 expandable interbody device offers similar anterior rim apophyseal contact commonly achieved using a banana-shaped cage but with the ease of insertion associated with a straight or football-shaped cage. Why is this design feature of interest to you as a spine surgeon?
CH: The Catalyft™ PL40 expandable interbody device design maximizes the interface between the cage and the anterior apophyseal ring to facilitate correction and reduce the likelihood of subsidence. The insertion of banana-shaped interbody devices can be challenging, particularly with an MIS approach. This can be exacerbated further at the L5-S1 disc space where the iliac crest can further limit the placement trajectory of the interbody cage. Catalyft™ PL40 expandable interbody device allows for similar engagement of the anterior apophyseal ring with a direct oblique or bilateral PLIF trajectory.
SR: I think the unique design of the Catalyft™ PL40 expandable interbody device allows greater flexibility to spine surgeons who have different interbody cage type preferences. Surgeons often prefer one particular interbody cage design over another because of how it may address that surgeon’s specific needs and concerns. With the Catalyft™ PL40’s hybrid design which includes 40 percent more surface area compared to Catalyft™ PL expandable interbody device, I think it gives spine surgeons with a preference for the “straight in” or “football” cage designs the ability to benefit from the additional feature of the “banana” cage with the increased anterior contact and greater surface area to reduce subsidence.
Q: The Catalyft™ PL expandable interbody device is compatible with the StealthStation™ S8 navigation system and allows the surgeon to see the implant in the collapsed and expanded positions during placement. How does this feature aid in executing your surgical plan?
SR: One of my favorite features of the Catalyft™ PL cage includes its compatibility with the StealthStation™ S8 navigation system because I appreciate the precise information this technology provides me with both planning and execution of my surgical plan.
As the field of spine surgery become more aware of the factors that contribute to improved short- and long-term patient outcomes, we are constantly evaluating and improving our surgical techniques and the devices we use to help us achieve these outcomes. By seamlessly integrating the Catalyft™ PL cage with the latest technologies, surgeons can obtain immediate feedback during the planning and placement of the cage within the disc space. I can’t think of anything more satisfying to a spine surgeon than real-time feedback for a patient on the operating room table that permits appropriate adjustments to be made on the fly.
CH: The compatibility of the Catalyft™ PL expandable interbody device with the StealthStation™ S8 navigation system facilitates precise placement of the cage within the disc space. Navigated interbody cage insertion allows surgeons to achieve ideal implant position. Further, visualization of the implant in both the collapsed and fully expanded positions provides a virtual representation of the potential sagittal correction achievable.
Q: A common drawback associated with expandable interbody cages is related to the delivery of autogenous bone graft and/or allograft bone graft material especially once the cage is expanded. How does the design of the Catalyft™ PL expandable interbody device facilitate bone graft delivery?
SR: The biggest challenge with expandable cages has historically been concerns with the “biologic gap” that can occur when an expandable cage is expanded. The Catalyft™ PL expandable interbody device is integrated with the Grafton™ DBF Inject graft delivery system, which I feel allows spine surgeons a more consistent and easier way to place bone graft directly around, through and into the interbody cage. I find this graft delivery system to be simple to load and very smooth in delivering the bone graft where needed, thus eliminating the potential for any biologic voids in the disc space or created by the cage’s expansion.
CH: While some implants have a mechanism for backfilling of the cage, Catalyft™ PL expandable interbody device goes even further. Not only can the biologic be delivered into the interbody cage following expansion, but the entire disc space can be filled through the cage. This can facilitate maximal biologic packing of the disc space both within and around the expanded Catalyft™ PL expandable interbody device. Further, eliminating pre-packing of the disc space can avoid compaction of the graft in front on the cage on insertion, which can at times limit anterior placement of the cage.
Conclusion
These surgeons see advantages in the Catalyft™ PL expandable interbody device. The design provides ease of insertion and offers surgeons flexibility based on their cage type preferences.
Further, both surgeons see advantages in the Catalyft™ PL expandable interbody device’s compatibility with the StealthStation™ S8 navigation system, which facilitates precise placement of the cage within the disc space. To reiterate Dr. Rajpal’s statement, “I can’t think of anything more satisfying to a spine surgeon than real-time feedback for a patient on the operating room table that permits appropriate adjustments to be made on the fly.”
The favorable reactions and experiences of these two spine surgeons describe how the features of the Catalyft™ PL expandable interbody device may provide certain advantages as surgeons are executing their surgical plans.
Indications
The Catalyft™ PL expandable interbody system is indicated for use as an intervertebral body fusion device in skeletally mature patients with degenerative disc disease (DDD - defined by discogenic back pain with degeneration of the disc confirmed by patient history and radiographic studies) at one or two contiguous levels of the lumbar spine (L2-S1). These DDD patients may also have up to Grade 1 spondylolisthesis or retrolisthesis at the involved levels. Additionally, the Catalyft™ PL expandable interbody system can be used with patients diagnose with spinal deformities as an adjunct to fusion. These patients should be skeletally mature and have undergone 6 months of non-operative treatment prior to surgery. Implants are used to facilitate fusion in the lumbar spine using autogenous bone graft and/or allograft bone graft comprised of cancellous and/or corticocancellous bone, and/or demineralized allograft bone with bone marrow aspirate. These implants are intended for use with supplemental internal fixation systems.
Disclaimers
This content is sponsored by Medtronic and contains the opinions of and personal surgical techniques practiced by Drs. Holland and Rajpal. The opinions and techniques presented herein are for information purposes only and the decision of which techniques to use in a particular surgical application should be made by the surgeon based on the individual facts and circumstances of the patient and previous surgical experience. Drs. Holland and Rajpal are paid consults for Medtronic. This interview, sponsored by Medtronic, is intended to educate, and train customers regarding the approved or cleared uses of Medtronic products. As such, unapproved products or indications are not discussed herein. You may contact Medtronic’s Office of Medical Affairs at 800.876.3133 ext. 6044 for any specific clinical questions you may have.