Complex fracture-dislocations of the proximal ulna and radius in adults: a comprehensive classification

Background: Complex fracture-dislocations of the proximal ulna and radius include multiple anatomic lesions, the management of which is known to be demanding. Although several classifications have been proposed, none appear to be exhaustive, and most of them have neither therapeutic nor prognostic value. The purpose of this study was to design a comprehensive classification that may provide a guide for the operative management of these injuries.

Materials and methods: The classification is aimed at identifying definite anatomic lesions, called the "main lesions," the presence of which can affect the prognosis and require peculiar treatments. The main lesions include (1) ulnar fracture (including its location with respect to the insertion of collateral ligaments and coronoid fracture), (2) radiohumeral dislocation, (3) proximal radioulnar dislocation, (4) radial fracture, (5) distal radioulnar joint and interosseous membrane lesion, and (6) humeral-ulnar dislocation. Intraobserver and interobserver reliability was assessed in 25 complex fracture-dislocations. Standard radiographs and computed tomography scans were analyzed by 3 independent observers.

Results: The main lesions were labeled by an alphanumeric system. Numbers 1 through 6 identified the type of ulnar fracture, and letters A through E indicated the dislocated joint or presence of a radial fracture. The direction of dislocation and the type of radial fracture were identified by Roman numerals, from I to III, placed after the letter. A κ value of 0.873 or greater resulted from intraobserver and interobserver evaluation.

Conclusion: We created a comprehensive classification of complex fracture-dislocations of the elbow. The classification appeared to be reproducible and may represent a useful tool for the management of such difficult injuries.