The role of bone scanning in severe frostbite of the feet in a mountaineer.

A 35-year-old man was admitted to our hospital 7 days after suffering a frostbite injury in feet while he was trying to reach the top of the Nanga Parbat mountain (height of 8,126meters). Within the first 24h after frostbite the patient received treatment based on warm baths, heparin, acetylsalicylic acid and non-steroidal anti-inflammatories in the base camp. A 740MBq 99mTc-MDP double phase bone scan in plantar view was performed 7 days after frostbite injury (Fig. 1) in aseptic conditions with a low energy/high resolution collimator. 57Co marks in distal ends of toes once removed dressings were also performed. The blood pool showed an absence of vascularisation in distal phalanx of both first toes. The delayed images also showed an absence of bone uptake in the same toes. The increases of uptake in other distal ends of toes in both phases were related to reparative changes. Twenty-eight days later a second bone scan (Fig. 2) was performed in the same conditions as the first one. The delayed phase did not show any modification in bone uptake. Bilateral amputations at the mid-proximal phalanx level were performed 10 days later. The line of demarcation was identical to the scan studies. Frostbite injuries affect frequently hands and feet. In mountain climbing the extreme conditions, such as high altitude, fatigue and below zero temperatures (Celsius scale), along with hypoxia, compensatory polycythemia, chronic dehydration and delayed medical care are factors that aggravate these injuries.1 The medical treatment (acetylsalicylic acid, warm baths, peripheral vasodilators, heparin, tissue plasminogen activator (tPA) and non-steroidal anti-inflammatories) must be introduced within the first 24h to prevent the amputation, especially tPA and heparin.2 In clinical practice, it is difficult to establish an early prognosis, sowe need four or five days to know if the injuries are superficial or deep and about 3–7 weeks to define the severity of the lesion and the amputation level. Bone scan can predict the amputation level earlier than clinical findings.On theotherhand, superficial frostbite is not a reliable indicator of the absence of the affectation of deep tissues and it is not uncommon that a frostbite, initially considered