Retro Comparison of Subsidence Following Interbody Devices in Lumbar Spine

The objective of this retrospective study is an investigational clinical follow-up, of patients treated with interbody fusion devices (IBFD), both expandable (EXP) and static (STC), according to their intended use and cleared labeling to understand IBFD design and technique characteristics that affect occurrence rates of subsidence. Patients treated with IBFD's (both EXP and STC) according to their intended use and cleared labeling 1. EXP IBFD's that expand in width and height demonstrate reduced occurrence of subsidence post-operatively when compared to EXP IBFD's that expand in height only and STC IBFD's. 2. EXP IBFD's that are comprised of multi-material composition with Polyetheretherketone (PEEK) endplate contacting surfaces demonstrate reduced occurrence of subsidence on post-operative radiographs when compared to EXP and STC IBFD's that are primarily comprised of Ti with Ti endplate contacting surfaces. 3. achieve radiographic fusion at a rate consistent with the state-of-the-art 4. achieve significant improvements in pain and function compared to baseline 5. experience adverse events at a frequency comparable to reported rates for TLIF or PLIF surgery 6. not demonstrate any intraoperative complications during the implant process 7. operative approach does not correlate with increased rates of subsidence