Preferred screw placement area identified by imaging based quadrant and heatmap analysis for long screw fixation in...

Ogawa I coracoid process fractures are relatively rare. Surgical fixation requires precise determination of the screw length and direction to avoid iatrogenic injuries. Identifying the preferred screw placement area (PSPA) through imaging techniques is crucial for enhancing surgical safety and stability. This study utilized shoulder computed tomography (CT) data from 100 adult patients, employing three-dimensional (3D) modelling and simulated surgeries to analyze the PSPA for long screw fixation in Ogawa I coracoid process fractures. Scapular Y-view two-dimensional (2D) fluoroscopic images were divided into quadrants. Using scatter plots and heatmap techniques, we identified the PSPA, cautious screw placement area (CSPA), and danger screw placement area (DSPA). Preliminary validation was conducted through a cadaveric bone experiment and 9 clinical cases. The screw tip clusters were primarily distributed in the posterior-lower quadrant of the scapular Y-view images. The red and orange regions on the heatmap indicate the PSPA. The lengths of the longest (L1) and shortest screws (L2) were 53.44 ± 5.37 mm and 40.74 ± 6.02 mm, respectively. Male patients required longer screws, with significant sex differences (P < 0.05). Cadaveric bone experiments and in vivo validation demonstrated that screw placement via the PSPA effectively prevented screw perforation. This imaging study, employing the quadrant method, explored a potential PSPA for long screw fixation in Ogawa I coracoid process fractures. Initial observations from cadaveric and clinical settings suggest that this approach might assist in intraoperative screw orientation and could contribute to a reduced risk of iatrogenic injury.