Evaluation of spinal deformity and its progression in pyogenic spondylodiscitis: A retrospective MRI study of 59 cases

Abstract

Introduction

Pyogenic spondylodiscitis management often remains conservative without surgical intervention, yet the risk of spinal deformity under such therapy is unclear.

Research question

This study explores spinal deformity progression in conservatively treated patients and identifies predictive factors for deformity advancement.

Material and methods

Retrospective cohort design with radiological data analysis from 59 patients with conservatively treated pyogenic spondylodiscitis. Deformities were categorized into four progression types reflecting severity: Type 1 (progressive vertebral body edema/endplate erosion), Type 2 (Type 1 plus disc space collapse), Type 3 (vertebral body destruction/mild translation), and Type 4 (significant segmental kyphosis >20°/severe translation).

Results

Among 59 patients, 66% exhibited progressive deformity over a mean follow-up of 10.75 months. The distribution of deformity progression was: Type 1 in two cases (3%), Type 2 in seven cases (12%), Type 3 in 13 cases (22%), and Type 4 in 17 cases (29%). Progression of deformity included a 92% increase in cases with segmental kyphosis >20°; and a 167% increase in cases with segmental translation. Risk factors for significant kyphosis included >50% vertebral body erosive destruction (p < 0.01) and the presence of an epidural abscess (p < 0.05). Lumbar region involvement significantly reduced the likelihood of spinal fusion at follow-up (p < 0.05). A paravertebral abscess was significantly associated with the presence of a fractured vertebrae at follow-up (p < 0.05).

Discussion and conclusion

This study underscores the importance of closely monitoring patients with conservatively managed pyogenic spondylodiscitis for progressive spinal deformity, and suggests considering early surgical intervention in cases with a high risk of progression.