In the U.S., more than 300,000 people suffer from back pain or spinal cord injuries. As a spine surgeon, you’ve likely seen your fair share of these injuries, ranging from issues like scoliosis to complications such as compressed or herniated disks.
Depending on the severity of the injury, you may be able to treat your patients using prescriptions and spinal blocks. However, in some cases, surgery is the solution.
When that’s the case, an interbody cage might be what you need to help get patients back on their feet. This guide dives into interbody cages, what they are, and how they can help people. It covers the materials they’re constructed of and the different types, plus their advantages for your patients.
What Is an Interbody Cage?
An interbody cage, or spinal cage, is a small, hollow medical implant used in spinal fusion procedures. It functions as a structural support, replacing the damaged or degenerated intervertebral disc to restore spinal stability and alleviate pain.
During spinal fusion, the interbody cage is inserted into the disc space previously occupied by the problematic disc. The cage is often filled with bone graft or a bone morphogenetic protein (BMP) to stimulate new bone growth.
This process facilitates the fusion of adjacent vertebrae, providing long-term stability to the spinal segment.
Materials Used to Construct Interbody Cages
Interbody cages are meticulously constructed from durable, biocompatible materials to ensure optimal performance and patient safety.
A few of these common materials are outlined in the table below.
| Material | Material Why It Works |
|---|---|
| Titanium | Lightweight, exceptionally strong, and non-magnetic. Titanium's biocompatibility minimizes the risk of adverse reactions. |
| PEEK (Polyether ether ketone) | Radiolucent for clear postoperative imaging, with elasticity mimicking natural bone. |
| Bio-absorbable Materials | Designed to dissolve gradually as the patient's bone heals, eliminating the need for implant removal. |
| Hybrid Materials (e.g., PEEK with Titanium) | Combine the advantages of multiple materials, offering radiolucency and enhanced bone growth potential. |
Selecting the appropriate material is critical for the success of the interbody cage, influencing its effectiveness, patient recovery, and long-term outcomes. Understanding the specific properties of each material allows for informed decisions tailored to individual patient needs.
Conditions Treated by an Interbody Cage
Interbody cages have seen a widespread application in treating a range of spinal conditions. There are countless instances where patients sought relief from debilitating back pain and other symptoms through the use of these devices.
A few examples include:
- Degenerative Disc Disease (DDD)
- Spondylolisthesis
- Spinal stenosis
- Herniated discs
Interbody cages significantly reduce pain and improve mobility for patients with these conditions as they help restore disc height, relieve nerve compression, and promote fusion. Here’s a closer look at how they work to provide relief for patients with these conditions.
1. Degenerative Disc Disease
This condition involves the breakdown of the shock-absorbing discs between your vertebrae. This can lead to persistent pain, limited range of motion, and weakness or numbness in the legs, drastically impacting your quality of life.
We’ve seen patients with severe degenerative disc disease regain their mobility after spinal fusion surgery involving interbody cages. These cages are incorporated into the space left by the removed disc, promoting fusion and stability between the vertebrae.
2. Scoliosis, Kyphosis, and other Spinal Deformities
Interbody cages have also shown to be tremendously successful in the treatment of spinal deformities like scoliosis (side-to-side curvature) and kyphosis (forward curvature). These cages can help to correct the curvature and get patients’ spines back into alignment.
3. Spinal Stenosis
Spinal stenosis is a narrowing of spaces within your spine, which can put pressure on your spinal cord and the nerves that travel through the spine. Surgeons can leverage the stability offered by interbody cages after decompression surgery (where elements causing nerve pressure are removed) to prevent a recurrence of spinal stenosis.
4. Herniated Discs
A herniated disc happens when the soft jellylike center of a spinal disc pushes out through a tear in the tougher exterior casing. When conservative treatments fail, an option could be a discectomy (disc removal) followed by spinal fusion using an interbody cage.
Types of Interbody Cages
The term “interbody cage” encompasses a variety of different types and styles, each with its own purpose. Here’s a closer look at a few of the different types and how they work.
1. Anterior Lumbar Interbody Fusion (ALIF) Cages
ALIF cages are leveraged when the surgical approach is taken from the front or anterior side of the body to reach the lumbar spine. This type is used in conditions such as degenerative disc disease or spondylolisthesis.
The cage design can range from rectangular blocks to more anatomically friendly circular designs based on the patient’s needs and the surgeon’s preferences. The AnyPlus® ALIF Interbody System is an example of this type of cage.
2. Posterior Lumbar Interbody Fusion (PLIF) Cages
Used when the surgical approach is from the back or posterior side, PLIF cages must meet the complex challenge of being compact (for ease of insertion) yet sturdy enough to hold up the vertebrae until fusion is complete. They are often used in situations where deformity is prominent or significant nerve root compression exists.
An example of a type of PLIF cage would be the AnyPlus® TPLIF Interbody System.
3. Transforaminal Lumbar Interbody Fusion (TLIF) Cages
Similar to their PLIF counterparts, these cages are used in the transforaminal approach, allowing access to the spine through a single incision on one side of the back. The cage design is typically crescent or kidney-shaped, making inserting it into the intervertebral space easier.
The AnyPlus® TLIF Interbody System is an example of this type of interbody cage.
4. Lateral Lumbar Interbody Fusion (LLIF) Cages
When direct lateral access to the spine is determined as the best approach, surgeons call upon LLIF cages. Often shaped like rectangles or wedges, these cages are designed to align and stabilize the patient’s spine from a sideways approach.
An example of this type of interbody cage might be the AnyPlus® Lateral Interbody System.
5. Expandable Interbody Cages
The latest innovation in interbody cages is the expandable kind. These cages are specially designed to be adjustable, meaning that they can be inserted when compact and then expanded once in place for an exact fit. With these cages, the possibility of adjacent segment disease, one of the potential long-term complications of spinal fusion, can be lowered.
An example of an expandable interbody cage is the Pulsar™ Expandable TLIF/PLIF Implant.
Benefits of Expandable Interbody Cages and Surgical Outcomes
Whereas interbody cages can, in general, provide benefits to your patients, expandable interbody cages can be particularly helpful.
For one thing, expandable interbody cages can provide better adjustability. Traditional interbody cages come in fixed sizes. While an experienced surgeon can effectively select and implement the best-fitting cage, it’s not always a perfect fit.
On the other hand, expandable interbody cages can be resized and fine-tuned during the implantation process, providing a more precise fit. This flexibility can lead to a better anatomic alignment, minimizing the risk of complications and contributing to a more effective spinal fusion.
Furthermore, expandable interbody cages offer significant advantages for minimally invasive spinal procedures due to their adaptability. Here are a few of them:
- Restore the disc heights and provide indirect decompression to the nerve
- Restore the original kyphosis/ lordosis of the patient body
- Reduce the damage to the vertebral body by putting collapsed cage to the disc space and then expand rather than putting a big cage to to the disc especially collapsed disc.
A few other benefits include less postoperative pain, quicker recovery times, and improved patient comfort.
Ensuring Long-term Success with Interbody Cages
Proper postoperative care is essential for the long-term success of interbody cages in your patients. A few steps to take to support your patients’ recovery with these devices include:
- Regular Check-ups: Patients must schedule routine check-ups with their spine surgeon to monitor recovery, assess fusion progress, and detect potential complications.
- Imaging Studies: Periodic X-rays or other imaging tests allow for visualization of the interbody cage, its placement, and the status of bone fusion.
- Lifestyle Modifications: Maintaining proper posture, engaging in physical therapy, managing weight, and eating a healthy diet can promote healing and long-term spinal health.
- Potential for Reoperation: Reoperation may be necessary in rare cases due to factors such as failed fusion or hardware issues. Early detection through follow-ups is key.
Patient and surgeon collaboration is crucial for successful long-term outcomes with interbody cages. This includes adherence to follow-up schedules, lifestyle changes, and open communication about any concerns.
Take Your Surgeries Into the Future With Interbody Cages
Interbody cages are a significant innovation in the field of spinal surgery. These devices play a crucial role in spinal fusion procedures, promoting stability, reducing pain, and improving patient outcomes.
As leaders in spinal solutions, GS Medical develops innovative, expandable interbody cages for optimized surgical outcomes and enhanced patient recovery. Our devices provide superior stability, adaptability, and a reduction in long-term complications.
Browse our products to find interbody cages that fit your surgical needs. Or, get in touch with our team to get a quote for one if you already know what you’re looking for for your practice.