Outcomes of Balloon Kyphoplasty for Vertebral Compression Fractures in Patients with Diffuse Idiopathic Skeletal Hyperostosis at the Distal End or Adjacent Vertebra of the Fused Segments.

Study design: A retrospective cohort study.

Purpose: To investigate the outcomes of balloon kyphoplasty (BKP) for vertebral compression fractures (VCFs) at the distal end or adjacent vertebra of the fused segments in patients with diffuse idiopathic skeletal hyperostosis (DISH).

Overview of literature: Vertebral fractures in the midportion of the fused segments in patients with DISH are generally unstable; thus, immobilization is recommended. However, VCFs classified as type A in the AO classification are observed at the distal end and adjacent vertebra of the fused segments, and treatment strategies for VCFs associated with DISH remain controversial.

Methods: The outcomes of 72 patients who underwent BKP for VCFs between 2015 and 2021 were retrospectively investigated. Patients with DISH were assigned to group D (n=21), whereas those without DISH were assigned to group ND (n=51). Back pain, incidence of subsequent adjacent fractures, reoperation rates, and local kyphosis were statistically analyzed.

Results: VCFs in group D occurred at the distal end or adjacent vertebra of the fused segments, and no fractures occurred in the midportion of the fused segment. Back pain improved in both groups, with no significant differences between them. Subsequent adjacent fractures were observed in three of the 21 patients in group D and 11 of the 51 patients in group ND, with no significant difference between them. Reoperation was performed in one patient each in groups D and ND, with no significant difference between the groups. Postoperatively, local kyphosis progressed significantly in group D.

Conclusions: Although local kyphosis is more advanced in patients with DISH, BKP is effective for VCFs at the distal end or adjacent vertebra of the fused segments and may be useful in older patients with high complication rates.