A strong association between Modic changes type 2 and endplate defects at non-fused segments after ACDF.

Purpose: To determine the association between Modic changes (MC) with other MRI parameters and clinical symptoms of cervical degenerative disc disease (DDD).

Methods: A retrospective analysis of data on patients with cervical DDD who underwent single-level anterior cervical discectomy and fusion. Preoperative demographic data (age, sex, surgical data) were collected, cervical MRI parameters (disc degeneration grade, MC and endplate defects, each determined at each cervical level) and clinical data (Numerical pain rating scale (NPRS) neck and arm, the Neck Disability Index (NDI)) were compared to preoperative data.

Results: The study included 121 patients at Visit 1 and 83 patients at Visit 2. The median follow-up duration was 26.5 [18.9; 33.1] months. Patients with MC had more intense NPRS-based neck pain before surgery compared to patients without MC (p=0.001). There were significant changes in MC rate at the C5-C6 levels due to a significant number of new MCs type 1 and MCs type 2 (p=0.002 and p<0.001, respectively). MC type 2 was associated with disc degeneration, endplate defects defects, patients' age and clinical scales (NDI, NPRS) (p<0.05). The endplate defects defect score threshold for predicting MC type 2 at the С3-С7 cervical levels was 5.

Conclusions: The factor predicting MC type 2 at the C3-C7 cervical levels is submaximal damage to the endplate. The MC rate is increased due to MC type 1 and MC type 2. MC types at the cervical levels may not represent consecutive stages of the same process.