Introduction
An abdominal aortic aneurysm (AAA) is a permanent dilatation of the infrarenal aorta that is 3 cm or greater in diameter or equivalent to 1.5 times the normal anteroposterior diameter. Risk factors for AAA include smoking, male sex, age greater than 65 years old, high systolic blood pressure (SBP), high body mass index (BMI), high serum triglycerides, high low-density lipoprotein (LDL), family history of AAA, coronary artery disease (CAD), atherosclerosis, stroke, and diabetes mellitus with concomitant CAD and peripheral artery disease (PAD). Of these, smoking is the greatest contributor to the development of AAA. In smokers, growth rate increases by an additional 0.35 mm/year and rupture rate doubles. Most unruptured AAA are asymptomatic and are found incidentally while investigating some other pathology. However, when symptomatic, unruptured AAA may present with unexplained abdominal discomfort and pain that radiates to the back, flank, or groin, as well as a pulsatile abdominal mass with or without a bruit heard at the mass.
The generalized pain from a symptomatic AAA may be confused with an orthopaedic etiology. A patient presenting with what seems to be a musculoskeletal (MSK) concern may logically lead a clinician towards a MSK differential diagnosis. However, it is important for orthopaedic clinicians to consider other etiologies when examining a patient in order to avoid missed diagnoses. In this case report, we discuss a case of an AAA incidentally found during an orthopaedic workup for posterior hip and low back pain. Our objectives are 1) to increase awareness of an AAA presenting as orthopaedic concerns and 2) to highlight the importance of a thorough history and a holistic physical exam in the orthopaedic clinic.