Comparing the Relative Stability of Transforaminal Lumbar Interbody Fusion (TLIF) Constructs

Biomechanical testing was performed at the Barrow Neurological Institute on seven human cadaveric L3-S1 specimens with a mean age 50 years with mean bone density 0.767 g/cm². Pure moments (±7.5 Nm) were applied in each plane while recording angular motion optoelectronically. Each specimen was tested using an intact disc and five different constructs.

Considerations for TLIF Surgery

• Aspen + unilateral pedicle screws-rods demonstrated similar range of motion to bilateral pedicle screws-rods
• This construct can be accomplished by way of a single minimally invasive midline incision
• TLIF + Aspen demonstrated similar range of motion to TLIF + unilateral pedicle screws-rods
• Studies suggest MIS TLIF performed in conjunction with unilateral pedicle screw instrumentation is an effective treatment for axial low-back pain in appropriately selected patients¹
• The minimally invasive Aspen device may offer an alternative to TLIF + unilateral pedicle screws-rods
• The minimally invasive Aspen device may be a viable option for TLIF surgery

Study Results

• Each construct was demonstrated to be effective at reducing angular range of motion (ROM)
• The Aspen device was most effective in limiting flexion and extension
• TLIF with unilateral pedicle screws-rods was the least stable configuration
• Addition of the Aspen to this construct significantly improved stability during flexion, extension, lateral bending, and axial rotation (p<0.04)

To learn more about the biomechanical testing results, please contact your local
Lanx representative.

¹ Deutsche H, Musacchio M Jr. Minimally Invasive Transforaminal Lumbar Interbody Fusion with Unilateral Pedicle Screw Fixation. Neurosurg Focus. 2006;20(3):E10.