Association between radiographic and functional outcome in vertebral osteomyelitis SPONDIMMO, a 6-month prospective...

This study aimed to describe radiographic and functional evolution over 6 months in a large cohort of VO patients.

We prospectively recruited patients with VO from 2016 to 2019 in 11 French centers. X-rays were performed at baseline, 3 months, and 6 months to assess progression using structural and static criteria. Functional impairment was evaluated using the Oswestry Disability Index (ODI) at 3 months and 6 months.

Two hundred and twenty-two patients were included. Mean age was 67.8±14 years, mostly men (67.6%). After 3 months, there was a significant increase in vertebral fusion (16.4% vs 52.7%), destruction of vertebral bodies (10.1% vs 22.8%), and of all the static features (frontal angulation (15.2% vs 24.4%), segmental (34.6% vs 56%) and regional (24.5% vs 41%) kyphosis). From 3 to 6 months, among the different X-ray abnormalities, only the complete fusion progressed significantly (16.6% vs 27.2%). Median ODI showed significant improvement from 3 to 6 months (24, IQR [11.5-38] vs 16, IQR [6-34]). At 6 months, 14.1% of the patients had a severe disability, 2% a major disability. The persistence of vertebral destruction at 6 months was associated with a higher ODI (16, IQR [7.5-30.5] vs 27, IQR [11.5-44.5]). No differences in radiological progression were observed with immobilization using a rigid brace.

Our study demonstrates structural and static radiographic progression after 3 months. Only the complete fusion progressed over the long-term. Functional impairment was associated with persistence of vertebral destruction.