Lumbar dysfunction is a common diagnosis that the physical therapist encounters on a daily basis. The etiology oi the patient's symptoms can be mechanical or systemic, and this must be discerned so that appropriate care may be provided for the patient. When signs and symptoms are present that do not suggest a mechanical etiology, the physical therapist must be able to recognize this and refer the patient appropriately. This case study describes lumbar pain of an insidious onset in an otherwise healthy 32-year-old male and the evolution oi systemic signs and symptoms which were initially thought to have a mechanical or nonsystemic etiology. Discussion is directed toward the clinical presentation oi osteomyelitis, the importance of a thorough review of a patient's medical history, and a complete physical examination in determining ii the presenting complaints are mechanical or systemic in etiology.