Minimally Invasive Intervertebral Cage


Project ID:  D2011-10



Spinal fusion procedures, also called interbody fusion, can be effective to reduce and in some cases eliminate numbness, weakness, and pain stemming from numerous medical conditions including, but not limited to disc degeneration, spondylolisthesis, and disc herniation. In case of chronic back pain or weakness, spinal fusion procedures generally are recommended only as a last resort. Such procedures involve expanding the spacing between vertebrae by surgically removing an improperly functioning disc and replacing it with a lumber interbody fusion (LIF) device, often called a "cage."

Invention Description:

Novel intervertebral cage inserted between vertebral bodies through a single, small incision (approx. 6 mm.).


Spinal disc replacement due to disease or other conditions.


  • Eliminates the need to remove all or most of the posterior support structures, increasing overall structural stability and reducing the risk of transitional syndrome.
  • Allows for increased structural stability of the fusion construct and provides higher, consistent, compressive loads necessary for a more successful fusion.
  • Utilizes "open" loop design to minimize the horizontal profile during insertion.
  • Unique design holds desired shape when secured upon insertion.
  • Segment height is dependent upon specific vertebrae to be fused and patient measurements.
  • Preferred material of cage wall segments has proven efficacy, biocompatibility, cost-effectiveness, strength, and modulus closer to bone than that of stainless steel.
  • Upon insertion, cage features open cavity for placement of bone graft material.
  • Wall segments may be safely decoupled and retrieved.
  • Requires shorter procedural time, reduces risk of complications and results in faster recovery

IP Status:                     Issued patents: US 9,561,115, South Korea 10-2043737, EP (France, Germany) 2758008,  Japan 6030140

Publications:                  Taheri Andani, Masood, Walter Anderson, and Mohammad Elahinia. "Design, modeling and experimental evaluation of a minimally invasive cage for spinal fusion surgery utilizing superelastic Nitinol hinges." Journal of Intelligent Material Systems and Structures 26.6 (2015): 631-638



Patent Information:
Medical Device
For Information, Contact:
Katherine Pollard
Licensing Associate
The University of Toledo
Mohammad Elahinia
Cory Chapman
Vijay Goel
Interbody fusion
Intervertebral cage