Abstract
Low back pain and, to a lesser degree, associated flank pain are common presentations to an integrative musculoskeletal clinic. Most cases have a neuromusculoskeletal or, less commonly, a urological etiology. Myelofibrosis is a chronic, uncommon blood neoplasm. Here, we describe the clinical presentation and diagnostic workup of a 76-year-old male who complained of back and side pain that did not respond to an initial trial of care. The case is followed through the diagnostic process, leading to the final diagnosis of myelofibrosis. This case emphasizes the need for further workup and a broad-spectrum differential diagnosis in cases of back and flank pain that do not respond to care, including consideration of myelofibrosis as a rare etiology.