According to the Young–Burgess system, these injuries are classi?ed as follows:
AC 1: Pubic diastasis <2.5 cm, either at the symphysis or through sagittal ramal fractures;
AC 2: Pubic diastasis >2.5 cm and anterior SIJ disruption;
AC 3: Pubic diastasis >2.5 cm, anterior and posterior SIJ disruption.
根据Young–Burgess系统，此损伤分为以下几类：
AC 1型：耻骨分离<2.5 cm，于耻骨联合处或矢状位穿耻骨支骨折；
AC 2型：耻骨分离>2.5 cm，骶髂关节前部分离；
AC 3型：耻骨分离>2.5 cm，骶髂关节前后部均分离。
AC 1 injuries are stable. AC 2 injuries are vertically stable but rotationally unstable due to anterior SIJ disruption—this is the classic ‘open-book’ fracture, where the intact posterior ligaments act as the ‘binding’ (Fig. 4). AC 3 injuries involve disruption of the posterior ligaments causing both vertical and rotational instability.
AC 1型损伤稳定。AC 2型损伤垂直稳定，但由于骶髂关节前部分离致旋转不稳，呈典型的“开书样”骨折，未受损的后方韧带充当“装订线”(图4)。AC 3型损伤包括后方韧带断裂引起垂直和旋转均不稳。
图4：AC 2型骨折。注意耻骨联合分离而后部韧带完整。此即为“开书样”骨折。
11. Lateral compression
11. 侧方挤压型
This is the most common type of pelvic fracture [22]. Lateral forces cause internal rotation of the hemipelvis. This results in coronal ramal fractures, contralateral SIJ disruption and central acetabular fractures. Unlike AP compression fractures, lateral compression injuries have a high association with sacral fractures, reported to be in the region of 88% [22].
这是骨盆骨折最常见的类型 [22]。侧方暴力引起半骨盆向内旋转。这导致冠状位上耻骨支骨折，对侧骶髂关节分离和髋臼中央骨折。与前后挤压骨折不同，侧方挤压损伤与骶骨骨折高度相关，报道称大约为88%[22]。
Pelvic volume tends to reduce in lateral compression fractures,with haemorrhage more likely to tamponade spontaneously.Young–Burgess classi?cation is as follows:
LC 1: Ipsilateral ‘buckle’ sacral and coronal pubic rami fractures;
LC 2: Type 1 + ipsilateral iliacwing fracture or posterior SIJ disruption;
LC 3: Type 2 + external rotation of the contralateral hemipelvis±contralateral saggital ramal fractures.
Type 1 fractures are stable, types 2 and 3 are rotationally unstable but vertically stable owing to the intact posterior sacroiliac ligaments (Fig. 5a and b).
由于出血能够自发填塞，侧方挤压型骨折骨盆容积倾向于减少。Young–Burgess分类如下：
LC 1型：同侧骶骨扭转，冠状位耻骨支骨折；
LC 2型：1型+同侧髂骨翼骨折或后部骶髂关节分离；
LC 3型：2型+对侧半骨盆外旋转±矢状位耻骨支骨折。
1型骨折稳定，2型和3型由于骶髂后韧带完整表现旋转不稳而垂直稳定(图5a- b)。
