Choosing the Right Interbody Fusion Cage

Captiva Spine titanium interbody fusion cages

Interbody fusion cages can be classified according to the region of the spine where they should be implanted and the material they are made of.

• Types of interbody fusion cages according to the region of the spine where they will be placed:
  • Cervical interbody fusion cages
  • Thoracolumbar interbody fusion cages
  • Lumbar interbody fusion cages

• Types of interbody fusion cages according to their material:
  • PEEK interbody fusion cages: PEEK is a radiotransparent polymer that offers very high fusion rates and negligible subsidence values (sinking of the implant into the bone structure)
  • Titanium interbody fusion cages
  • Stainless steel interbody fusion cages

B.Braun PEEK interbody fusion cage

The surgical approach used for implant placement will depend on the type of vertebrae, the disorder, and the patient’s health. It will influence the stability of the spacer, or cage, determining a greater or lesser risk of device migration.

There are four main surgical approaches:

• Anterior: The intervertebral spacer is inserted through the anterior area of the vertebra. This is the most suitable technique for cervical cages. This is referred to as Anterior Cervical Interbody Fusion or ACIF.

• Posterior: The spacer is inserted through the posterior area of the vertebra. This technique is widely used for lumbar cages. This is referred to as Posterior Lumbar Interbody Fusion or PLIF.

• Transforaminal: This surgical approach is often used for lumbar disorders. This is referred to as Transforaminal Lumbar Interbody Fusion or TLIF. This procedure allows the surgeon to insert a bone graft and a cage into the disc space with only a slight lateral displacement or retraction of the nerve roots. Compared to the PLIF method, this technique reduces the risk of injury and scarring around the nerve roots.

• Lateral: This surgical approach is sometimes called DLIF (Direct Lateral Interbody Fusion) or XLIF (Extreme Lateral Interbody Fusion), but these terms both refer to the same technique. Surgical access is via an incision in the lower lateral region of the abdomen. The damaged disc is removed and the space between the two vertebrae is filled with a bone graft. Over time, this graft grows through the spacer, forming a bone bridge that leads to spinal fusion. Sometimes the graft is reinforced with fixation devices such as plates, pedicle screws, rods, and bars. Fusion stabilizes the spine and relieves pain.

K2M expandable interbody fusion cage

It is possible to find interbody fusion cages with specific characteristics. Here are some examples:

• Expandable interbody fusion cages
• 3D-printed interbody fusion cages
• Interbody fusion cages with integrated arthrodesis plate
• Pre-filled interbody fusion cages

Surgery to implant a cage can involve several risks. These are the main ones:

• Implant displacement or migration
• Bone deposition around the implant
• Fracture of the spinous apophysis resulting from the introduction of the spacer
• When pedicle screws are used, they may break or loosen
• It is possible that the implant will not provide the patient with sufficient relief from pain and other symptoms and that they will have to undergo a new surgical procedure
• Lower rate of spinal fusion in smokers

The patient can resume normal daily activities two to six weeks after the intervertebral spacer implant surgery, but only if approved by the doctor. There are, however, some basic precautions to be taken in the post-operative phase:

• If, shortly after surgery, the patient has to undergo an examination or treatment for another reason, they must inform the prescribing doctor that they have recently had spinal surgery.
• Failure to comply with the post-operative care recommended by the doctor can lead to the reappearance of symptoms and manifestations of physical discomfort. Intense physical activity too soon after surgery can even lead to a fracture of the spinous apophysis.
• After discharge from the hospital, physiotherapy may be necessary. The doctor may also schedule an examination and follow-up appointment six weeks later. However, as soon as the patient feels able, they can start practicing activities that don’t require a great deal of physical effort.