Heterotopic Ossification After Stroke: Clinical Profile and Severity of Ossification

The aim of this study was to evaluate heterotopic ossification (HO) prevalence after stroke, describing clinical features and investigating predictors of HO and its severity.

A cross-sectional study was carried out in 7 rehabilitation centers (Sarah Network) from 2004 to 2013.

Among 17,794 stroke cases, 235 patients (1.3%) presented clinical and radiological evidence of HO. A log-binomial model with robust variance estimated the prevalence ratio of 1.3% in 10 years. A multinomial logistic regression was performed to investigate the predictors of HO and its severity. The presence of hemorrhagic stroke (prevalence ratio [PR] = 4.75; 95% confidence interval [CI] PR = 3.38; 6.68) and ischemic stroke with hemorrhagic transformation (PR = 3.08; 95% CI PR = 1.63; 5.81), male sex (PR = 1.60; 95% CI PR = 1.16; 2.22), spasticity (PR = 13.78; 95% CI PR = 8.59; 22.10), and cognitive impairment (PR = 1.88; 95% CI PR = 1.36; 2.60) were independently associated with HO. Patients with HO were younger (P < .0001) and presented a shorter time of disease (P = .013). Young adult patients were more likely to develop severe HO (odds ratio = 2.80, 95% CI 1.09; 7.20) than were elderly patients. Severe HO was also related to heavy alcohol consumption (2.45; 1.03-5.84) and involved 2 or more joints (5.34; 1.85-15.36). There was an association with use of invasive ventilation (6.30; 2.13-18.63) at the acute stroke phase and patients were dependent on activities of daily living after stroke (3.90; 1.00-15.19).

Despite the small prevalence of HO after stroke, this 10-year multicenter study was able to identify several associated factors related to the management and severity of stroke as well as the hemorrhagic subtype.