Spine immobilization and neurological outcome in vertebral osteomyelitis SPONDIMMO, a prospective multicentric cohort.

Objective: The aim of our study was to describe spine immobilization in a multicentric cohort of vertebral osteomyelitis (VO), and evaluate its association with neurological complications during follow-up.

Methods: We prospectively included patients from 2016 to 2019 in 11 centers. Immobilization, imaging, and neurological findings were specifically analyzed during a 6-month follow-up period.

Results: 250 patients were included, mostly men (67.2%, n=168). Mean age was 66.7±15 years. Diagnosis delay was 25 days. The lumbo-sacral spine was most frequently involved (56.4%). At diagnosis, 25.6% patients (n=64) had minor neurological signs and 9.2% (n=23) had major ones. Rigid bracing was prescribed for 63.5% (n=162) of patients, for a median of 6 weeks, with variability between centers (P<0.001). The presence of epidural inflammation and abscess on imaging was associated with higher rates of rigid bracing prescription (OR 2.33, P=0.01). Frailness and endocarditis were negatively associated with rigid bracing prescription (OR 0.65, P<0.01, and OR 0.42, P<0.05, respectively). During follow up, new minor or major neurological complications occurred in respectively 9.2% (n=23) and 6.8% (n=17) of patients, with similar distribution between immobilized and non-immobilized patients.

Conclusion: Spine immobilization prescription during VO remains heterogeneous and seems associated inflammatory lesions on imaging but negatively associated with frailness and presence of endocarditis. Neurological complications can occur despite rigid bracing. Our data suggest that in absence of any factor associated with neurological complication spine bracing might not be systematically indicated. We suggest that spine immobilization should be discussed for each patient after carefully evaluating their clinical signs and imaging findings.