ABSTRACT
This article describes a case of a rare malignant neoplasm presenting to the emergency department with common symptomatology and its subsequent identification using a simple physical examination technique. Discussion includes a description of this rare soft tissue sarcoma and a consideration of the value of the psoas sign as a part of the routine abdominal exam to detect intra-abdominal and retroperitoneal pathology. In conclusion, this article acts as a reminder to all clinicians that uncommon and significant pathology may present to the emergency department masquerading as a common, seemingly benign, complaint, but can be clinically identified using simple techniques available to all and rapidly investigated using appropriate special investigations.