Postoperative Sclerotic Modic Changes After Transforaminal Lumbar Interbody Fusion: Whether It Is Different Between Nano-hydroxyapatite/Polyamide 66 and Polyetheretherketone Cage?

OBJECTIVE

This study aimed to compare short-term outcomes between nano-hydroxyapatite/polyamide 66 (n-HA/PA66) cage and polyetheretherketone (PEEK) cage in sclerotic Modic changes (MCs) following transforaminal lumbar interbody fusion and explore the effects of these cages on postoperative sclerotic MCs.

METHODS

We retrospectively screened 1076 patients from September 2012 to September 2024 identifying 134 patients (154 levels) with sclerotic MCs after transforaminal lumbar interbody fusion. Patients were divided into the n-HA/PA66 group and the PEEK group. The incidence, timing, location of sclerotic MCs, clinical and radiological outcomes were compared between the 2 groups.

RESULTS

The incidence of sclerotic MCs was 9.9% (66/669) in the n-HA/PA66 group and 16.7% (68/407) in the PEEK group (P < 0.001). Visual analog scale and Oswestry Disability Index scores were comparable between the 2 groups. Both the n-HA/PA66 and PEEK groups demonstrated similar fusion rates at 3 and 6 months after operation and at the final follow-up. At the final follow-up, the mean cage union ratios exposed to the upper and lower endplates of the n-HA/PA66 group on the coronal and sagittal plane were significantly larger than those of the PEEK group (all P < 0.001). However, there were no significant differences between the 2 groups in intervertebral space height, lumbar lordosis, and segmental lordosis.

CONCLUSIONS

The incidence of postoperative sclerotic MCs in the n-HA/PA66 cage was significantly lower than that in the PEEK, which may be attributed to the better fusion status of the n-HA/PA66 cage. These results indicate that the n-HA/PA66 cage is a good biomimetic cage and may be beneficial for postoperative sclerotic MCs.