Postoperative Sclerotic Modic Changes After Transforaminal Lumbar Interbody Fusion: The Prevalence, Risk Factors, and Impact on Fusion

Abstract

Study design: A retrospective cohort study.

Objective: This study aimed to assess postoperative sclerotic modic changes (MCs) following transforaminal lumbar interbody fusion for lumbar degenerative disc disease, investigating their prevalence, risk factors, and association with clinical outcomes.

Summary of background data: Sclerotic MCs may occur in patients with lumbar degenerative disc disease after lumbar interbody fusion. The incidence and characteristics of postoperative sclerotic MCs, as well as their clinical impact, are unknown.

Materials and methods: The study included 467 patients (510 levels) who underwent single or two-level transforaminal lumbar interbody fusion surgery, divided into a postoperative sclerotic MC group (60 patients, 66 levels) and a non-MC group (407 patients, 444 levels). The time of development and location of postoperative sclerotic MCs, fusion rate, cage subsidence, bilateral process decompression, and cross-link usage were recorded. Preoperative, postoperative, and follow-up visual analogue scale and Oswestry disability index scores were collected. Multivariable logistic regression was used to evaluate factors associated with the development of postoperative sclerotic MCs.

Results: The prevalence of postoperative sclerotic MCs was 12.8%. The postoperative sclerotic MC group had a higher body mass index (BMI). The postoperative sclerotic MC group demonstrated a fusion rate of 47%, significantly lower than that of the non-MC group (71%) at six months post-operation. At final follow-up, the fusion rate in the postoperative sclerotic MC group was 62%, significantly lower than that of the non-MC group (86%). Postoperative visual analogue scale and Oswestry disability index scores were significantly higher in the group with postoperative sclerotic MCs. BMI and osteoporosis were significantly associated with the development of postoperative sclerotic MCs.

Conclusion: Postoperative sclerotic MCs generally appear within the first year after surgery, with a prevalence of 12.8%. The presence of postoperative sclerotic MCs can adversely impact postoperative outcomes. To prevent postoperative sclerotic MCs, the authors postulate extending the immobilization period with external bracing and improving the management of BMI and osteoporosis in the perioperative time window.