Different Degeneration Patterns of Paraspinal Muscles Between Double-Level and Single-Level Lumbar Spondylolisthesis: An Magnetic Resonance Imaging Analysis of 140 Patients

Degeneration of MF, ES, and PM is more severe in dl-DLS patients, particularly at the spondylolisthesis level. Severe paraspinal muscle degeneration can lead to spinal force imbalance and progression from sl-DLS to dl-DLS. The degradation of PM and ES correlates negatively with PT and SVA, indicating a link to pelvic decompensation and SVA abnormalities, potentially causing disproportionate degenerative changes in dl-DLS patients.