FRACTURES OF THE CLAVICLE IN THE ADULT - EPIDEMIOLOGY AND CLASSIFICATION

From 1988 to 1994 a consecutive series of 1000 fractures of the adult clavicle was treated in the Orthopaedic Trauma Clinic of the Royal Inf irmary of Edinburgh, In males, the annual incidence was highest under 20 years of age, decreasing in each subsequent cohort until the sevent h decade. In females, the incidence was more constant, but relatively frequent in teenagers and the elderly. In young patients, fractures us ually resulted from road-traffic accidents or sport and most were diap hyseal, Fractures in the outer fifth were produced by simple domestic falls and were more common in the elderly. A new classification was de veloped based on radiological review of the anatomical site and the ex tent of displacement, comminution and articular extension. There were satisfactory levels of inter-and intraobserver variation for reliabili ty and reproducibility, Fractures of the medial fifth (type 1), undisp laced diaphyseal fractures (type 2A) and fractures of the outer fifth (type 3A) usually had a benign prognosis. The incidence of complicatio ns of union was higher in displaced diaphyseal (type 2B) and displaced outer-fifth (type 3B) fractures. In addition to displacement, the ext ent of comminution in type-2B fractures was a risk factor for delayed and nonunion.