[Combined fractures of the radius and the ulna at the elbow level in the adult. Analysis of 120 cases after more than 1 year].

Purpose Of The Study: The purpose of this study was to increase the knowledge about these rare and serious injuries and to produce guidelines for a more successful ORIF.

Material: 120 cases of combined fractures in adults with late results (minimum one year) stored in the AO Documentation-Center between 1979 and 1989 were analyzed. Monotrauma was dominant, additional injuries were rare. No vasculo-nervous lesions were reported. 15 fractures were open. For the ulna 4 fractures types were isolated, fractures of the coronoid process and the radial head (CR) 25 cases. Olecranon and radial head fracture (OR) 22 cases. Combination of anterior (coronoid) and posterior (olecranon) ulnar fracture with radial head fracture (COR) 41 cases. Metaphyseal ulnar and radial head fractures (MR) 32 cases. For the radial head we have distinguished partial (61) and complete (59) fractures, the latter including 14 neck fractures.

Results: In the CR type indirect fixation technique was never perfect. Best results were obtained after ORIF of partial radial fractures. After resection, arthrosis (8/11) and valgus (8/11) were very frequent. In the OR type the stability was restored in simple fractures by the tension band technique even when the radial head was resected. In the severe COR type good results were rare. Arthrosis was important and frequent (36/41) especially after radial head resection. In the MR type ORIF of the radial head combined with ulnar plating gave the best results. Ulnar union was delayed or missing in 13 cases especially after radial head resection. Functional results after one year were better than expected on X-rays. This was due to immediate ORIF (92/120) and early mobilization. There were only 3 infections and 2 reflex-dystrophies.

Discussion: The Coronoid is the key-fragment of the ulna. It is best reduced in CR-Type under vision by an anterior approach. In COR-lesions its reduction should be the first step of ulnar ORIF. Comminutions in OR, COR and MR-Types showed a high number of delayed or non union. The reason may be a biological weakness (reduced vascularization) in these areas. Therefore we advocate for bridging plates (and cancellous grafts) for the stabilization of such areas, especially for the metaphysis where a strong valgus force appears after radial resection. Radial head as the lateral pillar of the elbow should be restored by ORIF in partial fractures (excellent results) and even in complete fractures (5/10 excellent results) under favourable conditions. Prosthesis is indicated in severe radial comminution or serious ulnar instability.