[Image-based guidance in shoulder traumatology. Initial clinical experience].

Computer-assisted systems are used frequently in pelvis and spine surgery but are still rare in general trauma and hardly ever used in shoulder surgery. The major limitation is the use of rigid markers and the problem of obtaining navigable images in the complex shoulder region. The aim of this study was to evaluate the use of a new image-based guidance system in shoulder traumatology. The system was used to implant a tightrope system in Tossy III lesions of the AC joint (n=7) and compared to the conventional method (n=8). Outcome parameters were duration of surgery, number of trials for perfect positioning of the guide wire, C-arm shots used till K-wire position is accepted, duration of radiation and surgeon's comment on usability and benefit. The new system did not shorten the surgical procedure significantly (45 vs 49 min, p=0.6) but reduced the average overall radiation time from 152 to 90 s (p=0.3). The number of shots to implant the guide-wire could be reduced significantly from 8 to 5 (p=0.01). The number of trials to implant the guide wire was less in the image-guided group compared to the conventional group (1 vs 2, p=0.02). For the first time image-based guidance was used in shoulder traumatology. The system holds high potential to assist surgeons without disturbing the workflow in assuring guide wire positioning, reduce the number of dangerous mistrials and reduce the emission of radiation.