We present the case of an adult haemophilia patient that at clinical examination showed intense painless synovitis in his left elbow, with full range of movement, which was unresponsive to 1 month of on-demand haematologic treatment at home. Radiological examination demonstrated a spontaneous displaced fracture of the olecranon secondary to severe osteolysis, due to advanced haemophilic arthropathy. Then, the patient was treated with a posterior plaster splint to immobilize the joint for 3 weeks together with secondary prophylaxis (3000 IU twice a week for 3 months). One month later the patient was better, with full range of movement, and the amount of swelling had improved. Regarding the outcome of the fracture, 6 months later there was no healing of the fracture, and the patient developed a painless nonunion that allowed him to return to his preinjury activities of daily living. As far as we know, this rare combination of problems (unresponsive synovitis, severe haemophilic arthropathy, spontaneous elbow fracture) has not been previously published in the literature.