Medical student LECOM Erie, Pennsylvania, United States
Case Diagnosis: Heterotopic Ossification (HO)
Case Description: A 28-year-old woman at 32 weeks gestation presented with acute hypoxic respiratory failure secondary to Covid-19 pneumonia. An emergency cesarean section was performed, which required intubation and ECMO. This patient’s course was complicated by DIC and a right intraparenchymal hemorrhage that resulted in a hemicraniectomy. During her stay in acute rehab, this patient developed HO of the right knee and both hips.
Discussions: There are two main categories that exist for HO and these include both traumatic and neurogenic. Traumatic causes of HO include muscular trauma, joint dislocation, and burns. Neurogenic causes include CVA, SCI, and TBI. Risk factors for developing HO include all of the above diagnoses as well as the presence of deep vein thrombosis (DVT), a tracheostomy, immobility, and coma. In this case, this patient had multiple risk factors for heterotopic ossification in addition to elevated ALP. However, she was being treated for several coexisting health problems which lead to delayed identification and treatment.
Conclusions: The case of this patient presents a complex scenario with the development of HO following tracheostomy and prolonged immobility. Elevated ALP levels, observed prior to the stroke and continuing thereafter, raised concerns regarding abnormal bone formation. However, the diagnosis of HO was not made until a month post-stroke for the knee and even later for the hips. The case highlights the challenge of diagnosing HO, especially in patients with multiple health issues coexisting. Prolonged immobility, such as that following a tracheostomy, can predispose individuals to HO. Timely imaging studies, especially in patients with the above risk factors for HO, need to be considered for early detection. The delayed identification of HO in this case demonstrates the challenges in managing such conditions.
