X-Plant Spinal Fixator




Lumbar fusion surgery is used for a variety of lumbar spine problems. Initially, most lumbar spine problems are treated conservatively. If symptoms persist, some individuals may be candidates for lumbar spine fusion surgery. The goal of such surgery is to relieve pain, numbness, and weakness, to restore nerve function, and to stop or prevent abnormal motion of the spine. Spinal implants are often employed for stabilization during such surgery. There is an ongoing debate, however, that spinal implants may have long-term adverse effects in promoting deterioration of vertebrae adjacent to fused sections of the lumbar vertebrae. Also, internal fixation techniques limit a patient’s ability to undergo an MRI (due to presence of metal plates and screws).


Description of Technology


MSU’s invention is an explantable (i.e., removable) spine fixator which provides temporary fixation for lumbar spinal fusion surgery. The device is inserted percutaneously (i.e., via needle-penetration rather than larger, open incisions), which allows for easy removal. The implant would be removed at a sufficiently early stage to significantly reduce the risk of deterioration of adjacent vertebrae. A key feature of this technology is that the metal plate connecting the two pins (and providing the structural stability for the area of the fused vertebrae during the post-operative fusion process) is located outside of the muscle covering the vertebrae (but under the surface layer of skin and fat), greatly reducing the level of invasiveness in removing the spinal implant after the fused vertebrae have knitted.


Key Benefits

  • Decreases adjacent segment degeneration: The invention allows easy removal which relieves stiffness at and around the fused segment and potentially mitigates adjacent segment degeneration.
  • Minimally invasive: The fixator requires only two incisions — this subcutaneous placement reduces risk of infection seen with external fixators.
  • Less muscle stripping and necrosis: The percutaneous technique avoids muscle stripping and necrosis seen with other techniques.
  • Allows for better sleeping during recovery period: Unilateral placement of the fixator allows the patient to sleep on their other side during recuperation.




MSU’s invention allows for a more simple removal of a device designed to stabilize a lumbar fusion (i.e., orthopedic treatment of lumbar spinal conditions).


Patent Status


Patent pending




Lawrence Mysliwiec


Tech ID




Alternative contact due to temporary leave:


Nina (Isi) Davis, Technology Marketing Manager, email: davisnin@msu.edu, phone (direct): (517)884-1829. 


Patent Information:


For Information, Contact:

Randy Ramharack
Technology Manager
Michigan State University
Lawrence Mysliwiec