Incidence and factors associated with development of heterotopic ossification after damage control laparotomy.

INTRODUCTION: The incidence of heterotopic ossification (HO) following damage control laparotomy (DCL) is unknown. Abdominal wall reconstruction may prove more challenging in patients with HO. This study examines the incidence and factors associated with HO in patients with an open abdomen following DCL.

METHODS: A retrospective review of all patients with an open abdomen after DCL at a level 1 trauma centre from 2009 to 2015 was conducted. Demographics and peri-operative outcomes of patients with and without HO were compared. Univariate and multivariable binary logistic regression models were used to determine the association of peri-operative factors with the development of HO.

RESULTS: 68 patients were included, of which 36 (53%) developed HO. On univariate analysis, development of HO was significantly associated with hollow viscus injury (OR, 3.89; CI 1.42-10.7), greater number of abdominal surgeries prior to definitive closure (OR, 1.84; CI, 1.10-3.05), non-fascial closure (OR, 4.33; CI, 1.44-13.1) and higher peak ALP (OR 1.01; CI, 1.00-1.02). The presence of a hollow viscus injury remained an independent predictor of HO on multivariable analysis after adjusting for covariates (OR, 3.77; CI, 1.22-11.6).

CONCLUSION: Heterotopic ossification develops in a high proportion of trauma patients following damage control laparotomy, particularly in the presence of hollow viscus injury. Its impact on delayed abdominal wall reconstruction and the efficacy of prophylaxis strategies merit further investigation.