Proliferative myositis of the latissimus dorsi presenting in a 20-year-old male athlete.

We describe the case of a 20-year-old rower presenting with an uncommon condition of Proliferative Myositis (PM) affecting the Latissimus Dorsi (LD). PM is a rare, benign tumour infrequently developing in the upper back. Its rapid growth and firm consistency may mistake it for sarcoma at presentation. Therefore, careful multidisciplinary work-up is crucial, and should involve appropriate radiological and histopathological investigations. Here, we propose the aetiology of LD PM to be persistent myotrauma induced by repetitive rowing motions. Symptoms and rate of progression ultimately determine the management which includes surveillance and/or conservative resection. There have been no documented cases of recurrence or malignant transformation.