In percutaneous pelvic trauma surgery, accurate placement of Kirschner wires (K-wires) is crucial to ensure effective fracture fixation and avoid complications due to breaching the cortical bone along an unsuitable trajectory. Surgical navigation via mixed reality (MR) can help achieve precise wire placement in a low-profile form factor. Current approaches in this domain are as yet unsuitable for real-world deployment because they fall short of guaranteeing accurate visual feedback due to uncontrolled bending of the wire. To ensure accurate feedback, we introduce StraightTrack, an MR navigation system designed for percutaneous wire placement in complex anatomy. StraightTrack features a marker body equipped with a rigid access cannula that mitigates wire bending due to interactions with soft tissue and a covered bony surface. Integrated with an Optical See-Through Head-Mounted Display (OST HMD) capable of tracking the cannula body, StraightTrack offers real-time 3D visualization and guidance without external trackers, which are prone to losing line-of-sight. In phantom experiments with two experienced orthopedic surgeons, StraightTrack improves wire placement accuracy, achieving the ideal trajectory within $5.26 \pm 2.29$ mm and $2.88 \pm 1.49$ degree, compared to over 12.08 mm and 4.07 degree for comparable methods. As MR navigation systems continue to mature, StraightTrack realizes their potential for internal fracture fixation and other percutaneous orthopedic procedures.

翻译：在经皮骨盆创伤手术中，克氏针的精确置入对于确保有效骨折固定、避免因沿不适宜轨迹穿破皮质骨而引发并发症至关重要。通过混合现实技术实现的手术导航能以低剖面形态辅助实现精确的导针置入。该领域现有方法因无法控制导针弯曲而难以保证准确的视觉反馈，故尚不适合实际临床应用。为确保反馈精度，我们提出了StraightTrack——一种专为复杂解剖结构下经皮导针置入设计的混合现实导航系统。该系统采用配备刚性穿刺套管的标记体，可缓解因软组织及覆盖骨表面相互作用导致的导针弯曲。通过与能追踪套管体的光学透视头戴式显示器集成，StraightTrack无需易受视线遮挡影响的外部追踪器即可提供实时三维可视化引导。在由两位经验丰富的骨科医师参与的体模实验中，StraightTrack将导针置入精度提升至$5.26 \pm 2.29$毫米和$2.88 \pm 1.49$度的理想轨迹范围内，而对比方法的误差超过12.08毫米和4.07度。随着混合现实导航系统的持续发展，StraightTrack展现了其在骨折内固定及其他经皮骨科手术中的应用潜力。