We report the case of a 55-year-old female with a rare presentation and different pathophysiology of Iselin's disease. Iselin's disease is a rare condition caused by traction apophysitis of the peroneus brevis tendon at the base of the fifth metatarsal bone. It is usually a case in the adolescent age group due to their repetitive use of the peroneus tendon in daily activities, but not in the elderly group. This type of apophysitis is rare and easily missed or misdiagnosed as a fracture in the base of the fifth metatarsal bone. However, a simple radiographic image can confirm the diagnosis. In this case, we aim to raise awareness of Iselin's disease for better comprehension of the clinical presentation, differential diagnosis, radiological features, management, and prognosis of Iselin's disease.