Factors associated with cervical instability in cervical myelopathy patients

J Neurosurg Spine 42:673–678, 2025

This study found a high prevalence (43.1%) of cervical instability in patients with cervical spondylotic myelopathy (CSM). Key factors associated with instability included cervical facet joint degeneration, increased T1 slope minus cervical lordosis (T1S−CL), and higher neck pain scores.

• Cervical instability is common in patients with cervical spondylotic myelopathy (CSM), with a prevalence of 43.1%.

• Instability was defined as ≥3-mm translational motion between adjacent vertebrae on flexion-extension radiographs.

• Key factors independently associated with cervical instability are higher cervical facet joint degeneration (FJD) scores, increased T1 slope minus cervical lordosis (T1S−CL), and higher visual analog scale (VAS) scores for neck pain.

• Age, sex, BMI, JOA score, and cervical range of motion were not significantly associated with instability.

• Facet joint degeneration plays a critical role in cervical instability, creating a cycle of degeneration and abnormal motion.

• Proper assessment of T1S−CL and FJD is essential for surgical decision-making in CSM patients.

• Study limitations include single-center design, moderate sample size, and exclusion of certain patient groups.

• Spine surgeons should pay special attention to these factors when determining treatment strategies for CSM.