A 40 year old male, previously well, presented with a posterior chest wall haematoma. Computerized tomography and ultrasound showed this to be intramuscular. Haematological indices were consistent with a diagnosis of polycythaemia vera. The haematoma and indices responded to hydroxyurea and venesection. This rare presentation of polycythaemia vera in a young person is described and the haemorrhagic complications of polycythaemia vera discussed.