Introduction: The variety of operative procedures for neglected Monteggia lesions reflect the difficulty to securely keep the radial head relocated. The amount and direction of angulation in case of an ulnar oste-otomy can only be defined intraoperatively by empirically searching for the appropriate position since the primary ulnar deformity has already partially or completely remodelled with growth in most cases.

Material and Methods: Retrospective study. From Janu-ary 1998 to May 2001 14 patients with late missed Mon-teggia lesions (Bado type I) underwent an osteotomy and external fixation (Hoffmann II compact, Howmed-ica) of the ulna combined with an open reduction of the radial head but without reconstruction of the anular ligament. The average age of 7 girls and 7 boys at the time of reconstruction was 9 years (5 to 15 years), the mean interval between the primary trauma and the reconstructive procedure 21 months (2 weeks to 7 years). Removal of the external fixator:12 weeks (7 – 16 weeks).

Results: In 12 patients the radial head remained located, in 2 patients it re-dislocated postoperatively. After early postoperative closed reduction in one patient and open relocation of the radial head in the other patient with modification of the external fixation, the radial head remained located. Preoperatively 7 of the 14 patients showed a decreased range of motion which improved postoperatively in most cases. Thirteen of the 14 patients had a clinical and radiological follow-up 14 months (3 – 44 months) after the reconstructive procedure. There were no complications.

Conclusions: Ulnar osteotomy, external fixation and open reduction of the radial head without ligament reconstruction or transarticular wire fixation proved to be a technically simple and safe procedure. It allows early functional after treatment without plaster. In case of posttraumatic overlength of the radius, it can be combined with acute or gradual lengthening of the ulna. Radio-humeral joint reconstruction in case of incongruency of the radial head and the capitullum, as well as reconstruction in adults with longstanding dislocation of the radial head are prone to failure.