Risk Factors in Hospitalized Patients With Burn Injuries for Developing Heterotopic Ossification—A Retrospective Analysis
Journal of Burn Care & Research
Aims: Heterotopic ossification (HO) is the formation of bone in locations where it should not occur. Little data is available on the risk factors for HO, a complication in burns patients. The aims of this study are to identify the risk factors for developing HO in patients with burns injuries and secondly to describe appropriateness of local prescribing and the frequency of adverse drug effects associated with disodium etidronate. Methods: Patients with HO at our tertiary referral burns unit
... erral burns unit were identified using the unit computer database. The control group were patients that were the next admission post admission of patient that subsequently developed HO. Demographic and clinical data as well as data on disodium etidronate therapy were collected. Univariate and multivariate techniques were used to identify risk factors for HO. Results: We reviewed 337 patients admitted over a 5-year period and identified 19 patients with HO (5.6%). A further 19 burn injury patients were included as controls. HO developed clinically and radiologically after a median time of 37 days (interquartile range [IQR], 30-40) and 49 days (IQR, 38-118) respectively. In univariate analysis HO development was associated with a greater %TBSA, inhalation injury, need for and length of mechanical ventilation, number of surgical procedures, sepsis, and longer time to active movement. In a multivariate analysis that adjusted for severity of burn injury by means of the Belgian Outcome in Burn Injury (BOBI) score, time to active movement was recognized as an independent risk factor for HO (odds ratio 1.48, 95% confidence interval 1.09-2.01). Disodium etidronate was prescribed to 18 of 19 patients at a median initiation dose of 18mg/kg (IQR, (16) (17) (18) (19) (20) (21) . Elevations in serum calcium concentrations were the only observed adverse effect. Conclusion: This study has demonstrated that delays in physical rehabilitation are predictive of the development of HO. Logically, a longer period of immobilization is linked with an overall higher severity of burn injury as evidenced by %TBSA, inhalation injury and need for ventilatory support and multiple surgical procedures.