Radiographic Classification for Degenerative Spondylolisthesis of the Lumbar Spine Based on Sagittal Balance: A...

Area of Science:

• Orthopedics
• Radiology
• Spine Surgery

Background:

• Degenerative spondylolisthesis of the lumbar spine (DSLS) is a common cause of chronic low back pain.
• A lack of consensus exists for a comprehensive analysis of DSLS.
• Assessing the reliability of a new classification system for DSLS is crucial.

Purpose of the Study:

• To evaluate the inter- and intraobserver reliability of a novel radiographic classification system for DSLS.
• To establish the consistency of a new classification based on sagittal alignment parameters.

Main Methods:

• Ninety-nine patients with DSLS undergoing surgery were included.
• Three observers analyzed lateral view radiographs, measuring segmental lordosis (SL), lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT), and sagittal vertical axis (SVA).
• Radiographs were classified into three types based on sagittal alignment, with reliability assessed using Fleiss κ, intra-class coefficient, and Cohen κ.

Main Results:

• Intraobserver repeatability showed almost perfect agreement (ICC > 0.92, Cohen κ > 0.89).
• Interobserver reproducibility was excellent, with a Fleiss κ value of 0.82 and 88-89% agreement.
• The classification demonstrated high reliability among observers.

Conclusions:

• The new DSLS classification system exhibits excellent inter- and intraobserver reliability.
• This classification serves as a simple, effective tool for preoperative analysis and surgical planning in DSLS.
• It aids surgeons in improving their understanding of sagittal balance in DSLS patients.