but symptoms were worse with weight bearing. He was an otherwise healthy and fit amateur triathlete. A clinical examination revealed bilateral ankle swelling, which was slightly larger on the left side, and pain to palpation along both medial malleoli. The range of motion was reduced in both ankle joints.We performed anteroposterior and lateral X-rays of both ankles which appeared normal (Fig. 1).According to the clinical examination and X-rays, the patient was sent home with a prescription for an oral nonsteroidal anti-inflammatory drug and with the diagnosis of muscle sprain.After fifteen days he was again seen at the emergency traumatology clinic still complaining of bilateral ankle pain, simple analgesia did not help. Both medial malleoli were swollen and painful on palpation, more on the left side. He was able to fully weight bear on the right lower extremity and partially weight bear on the left lower extremity.We repeated the X-rays which now showed bilateral tibial stress fractures (Fig. 2). Laboratory reports did not show any abnormalities. Below-knee backslab for left lower extremity was applied, the patient got low molecular weight heparin protection, crutches, and instruction not to weight bear on the left side and partially weight bear on the right lower extremity.Regular follow-ups at the outpatient clinic every two weeks were performed. The patient was pain-free. After five weeks below the knee back slab was removed and additional X-rays were performed. The fracture of the right tibia was healed and callus formation was seen in the left tibia (Fig. 3).