Classification and epidemiology of mid-foot fractures

The epidemiology of mid-foot fractures is poorly understood. They are uncommon fractures that are often considered to be the result of high-energy injury. To examine the epidemiology of mid-foot fractures. A retrospective analysis of all mid-foot fractures presenting on an in-patient or out-patient basis to the Royal Infirmary of Edinburgh between 1998 and 2002 was undertaken. All fractures were classified according to a classification system modified from a previous classification of displaced navicular fractures. The annual incidence of mid-foot fractures was 3.6/105/year. The overall average age was 36.9 years. About 56% occured in females. Eighty-two per cent were isolated injuries and less than 5% were open injuries. Fifty per cent of the fractures were in the cuboid, 44% were in the navicular and 6% were in a cuneiform. Analysis shows that there are four basic fracture types. Females tend to be older and to have low-velocity injuries. The cuboid is most frequently fractured. Males tend to be younger and high-velocity injuries are more common. The navicular is more commonly fractured. Mid-foot fractures are usually low-velocity injuries which affect younger and middle aged patients. Females are older than males and it seems likely that age-related osteopenia is an important factor in females. Fractures of the navicular, cuboid and cuneiform bones are relatively uncommon and their epidemiology is poorly understood. We have undertaken a 5-year retrospective study of mid-foot fractures define the basic fracture types and to document their epidemiology.