A large heterotopic ossification in a 25 years old laparotomy scar

Heterotopic ossification (HO) is a benign condition when bone develops in tissues that do not usually ossify. The etiology is not fully understood but the condition can appear in variable locations, sizes and morphology in the body. We describe a large HO in a scar, discovered 25 years after a laparotomy of the upper abdomen. The calcification led to mechanical complaints and resection gave resolution of symptoms. HOs can be incidental findings on plain radiographs. CT-scan can show typical mature peripheral mineralization with central lucency. If symptomatic, resection must be performed after maturation. Maturation can be examined with activity-oriented imaging as 3-phase bone scan or SPECT-CT.