SCREW ARTHRODESIS OF THE ANKLE JOINT - TE CHNIQUE AND RESULTS

In ankle arthrodeses several clinical and biomechanical studies have s hown the superiority of the screw technique over external fixation. As a maximum of stability is a major goal, especially for functional aft er-treatment or in patients with poor bone stock, the arthrodeses tech nique at Hannover Medical School is performed with four screws. Two pa rallel anterior/posterior screws are placed from the tibia to the talu s, providing anterior stabilization. One screw posterio-medial has a p osterior tension-wiring effect and one screw placed through the fibula to the talus acts against rotational and sagittal translation. From M ay 1975 to May 1995, 225 ankle arthrodeses with internal or external f ixation technique were performed. Complications were found in 47% in t he external fixation treatment group (n = 44) and in 10% the patients stabilized with the screw technique (n = 181). Fifty of these 225 pati ents had a follow-up evaluation after an average of 7.4 years (externa l fixation, n = 22; screw fixation, n = 28). All patients were examine d and scored with three different scoring systems: (1) MHH Score, (2) Clinical Rating System according to Kitaoka et al. (1994) and (3) Outc ome Questionnaire for evaluating the overall outcome. The results from the questionnaire were compared to the clinical scores. Retrospective analysis revealed a higher rate of complications for arthrodeses perf ormed by external fixation. The overall results of all three different scoring systems showed a trend in favor of the screw-fixation techniq ue without reaching statistical significance (P > 0.05). The results o f the Outcome Questionnaire are statistically as valid as the two clin ical scoring systems.