ABSTRACT
Hematomas are a common occurrence in clinical practice, often resulting from trauma or underlying bleeding disorders. They can manifest with various symptoms depending on their location and size. While hematomas are typically straightforward to diagnose and manage, specific presentations can pose diagnostic challenges. We present the case of a growing post-traumatic right upper extremity mass in a 67-year-old male on anticoagulant medication, Xarelto (rivaroxaban) 20mg, with no history of bleeding disorders. Differential diagnoses include a benign lipoma or possible soft-tissue malignancy. The mass was surgically excised and sent to pathology, which confirmed it was a hematoma and led to a diagnosis of a chronic expanding hematoma. Ultrasonography, computed tomography, and magnetic resonance imaging are diagnostic modalities that can help distinguish different presentations. Despite the commonality of hematomas in clinical practice, atypical hematomas may also present unique challenges in diagnosis and management due to their varied clinical presentations and locations. This report underlines the importance of understanding hematomas' diverse etiologies, presentations, and imaging characteristics for appropriate treatment and diagnosis.