Venepuncture of the superficial veins in the forearm is considered a relatively safe procedure. We report two patients who presented with osteomyelitis of the proximal radius following venous cannulation of the median cubital vein, and one patient who developed osteomyelitis of the distal radius after cannulation of the cephalic vein. Osteomyelitis developing in proximity to a venepuncture site should raise the suspicion that a pathogen causing superficial thrombophlebitis has spread through the deep veins of the arm into the adjacent bone, thus causing osteomyelitis.