Institute of Forensic Medicine, School of Medicine, University of Belgrade, 31a Deligradska Str., Belgrade, Serbia.
Forensic Sci Int. 2010 Oct 10;202(1-3):13-6. doi: 10.1016/j.forsciint.2010.04.013. Epub 2010 May 1.
The aim of this study was to determine the frequency of brainstem pontomedullar lacerations among fatally injured car occupants in head-on collisions, as well as the concomitant cranial injuries, and to establish a possible underlying mechanism for brainstem laceration. Brainstem pontomedullar lacerations (PML) are often associated with fractures of the skull base (hinge, ring or pyramidal fractures) or with cervical spine fractures. Out of 705 cases of deceased car occupants involved in head-on car collisions, some form of head injury was present in 447 cases (63.4%). These cases included 353 men and 94 women with an average age of 38.2±15.8 years (range 16-89 years). The collected cases included 229 drivers, 164 front-seat and 54 rear-seat passengers. PML were present in 67 of these cases (15%), 50 men and 17 women with an average age of 42.9±15.6 years (range 15-77 years), including 32 drivers, 26 front-seat and 9 rear-seat passengers. In all of these cases the brainstem laceration was partial and the depth varied approximately from 4mm to 8mm. To understand the mechanisms by which PML occurs, we classified the head impact areas into frontal, lateral, posterior and chin area, depending on the injuries to the soft tissue of the head and scalp, as well as facial and cranial fractures. Injury impact area of the head was a good predictor of PML occurrence (χ(2)=131.112, df=3, p=0.000). Chin impact was most often associated with PML-38 cases (Wald. coeff.=5.805, df=1, p=0.016). Presence or absence of mandibular fracture was significant for PML occurrence (χ(2)=11.413, df=1, p=0.001): persons without mandibular fracture have 2.3 times greater risk for PML than those with fracture (odd ratio=7.196). Among the observed skull base fractures, the best predictor of PML was ring fracture (Wald. coeff.=30.729, df=2, p=0.000). Our study showed that PML was present in a significant number of car occupants sustaining head injuries in head-on collisions (15%). Impact to the chin with or without a ring fracture to the skull base most often led to this fatal injury, probably after collision with the dashboard.
本研究旨在确定正面碰撞中致死性汽车乘客的脑干桥延髓撕裂的频率，以及伴随的颅损伤，并确定脑干撕裂的可能潜在机制。脑干桥延髓撕裂（PML）常与颅底骨折（铰链、环或金字塔形骨折）或颈椎骨折相关。在 705 例死于正面碰撞的汽车乘客中，有 447 例（63.4%）存在某种形式的头部损伤。这些病例包括 353 名男性和 94 名女性，平均年龄为 38.2±15.8 岁（范围 16-89 岁）。所收集的病例包括 229 名驾驶员、164 名前排乘客和 54 名后排乘客。在这些病例中，67 例（15%）存在 PML，50 例为男性，17 例为女性，平均年龄为 42.9±15.6 岁（范围 15-77 岁），包括 32 名驾驶员、26 名前排乘客和 9 名后排乘客。在所有这些病例中，脑干撕裂均为部分性的，深度约为 4mm 至 8mm。为了了解 PML 发生的机制，我们根据头部软组织和头皮、面部和颅骨骨折的损伤情况，将头部撞击区域分为额部、侧部、后部和颏部区域。头部的损伤撞击区域是 PML 发生的一个很好的预测因子（χ(2)=131.112，df=3，p=0.000）。颏部撞击最常与 PML-38 例相关（Wald. coeff.=5.805，df=1，p=0.016）。下颌骨骨折的存在与否对 PML 的发生有显著影响（χ(2)=11.413，df=1，p=0.001）：没有下颌骨骨折的人发生 PML 的风险比有骨折的人高 2.3 倍（比值比=7.196）。在所观察到的颅底骨折中，对 PML 最好的预测因子是环骨折（Wald. coeff.=30.729，df=2，p=0.000）。我们的研究表明，在正面碰撞中头部受伤的汽车乘客中，PML 的发生率相当高（15%）。颏部或颅底环骨折的撞击最常导致这种致命的损伤，可能是在与仪表盘碰撞之后。
