Effectiveness of Grade I Spondylolisthesis: An Overview

The study, Effectiveness of Grade I Spondylolisthesis, launched with funding from Medtronic and additional support from DePuy. The study takes a cohort of 13 Quality Outcomes Database (QOD) participating sites to examine respective surgical approaches in treating patients with spondylolisthesis. Data from July 1, 2014, to June 30, 2016, was analyzed.

Specific aims of the study include:

  • A comparison of the effectiveness of decompression alone and decompression with fusion using validated 1‐ and 2‐year patient‐reported outcomes data;
  • A comparison of the effectiveness of surgery for 1‐level spondylolisthesis with 2‐level spondylolisthesis with stenosis; and
  • An analysis of the current state of U.S. spine surgical practice regarding grade I degenerative spondylolisthesis, including the surgical parameters of blood loss and hospital length of stay.

Erica F. Bisson, MD, FAANS, serves as the study’s Principal Investigator along with additional leadership from Mohamad Bydon, MD, FAANS; John Joseph (Jack) Knightly, MD, FAANS; and Praveen V. Mummaneni, MD, FAANS.

Study Update


  • The study contains 412 completed subjects with 24+ month imaging uploaded.
  • Abstracts as well as oral and poster presentations citing the study (15‐20) have been accepted nationally and internationally over the past year; there have been two podium presentations at national neurosurgical meetings.