Singleton James A G, Gibb I E, Bull A M J, Clasper J C
Department of Bioengineering, Imperial College London, London, UK.
Royal Centre for Defence Medicine, Defence Centre for Imaging, Birmingham, UK.
J R Army Med Corps. 2014 Jun;160(2):175-9. doi: 10.1136/jramc-2013-000217. Epub 2014 Jan 9.
The accepted mechanism of blast-mediated traumatic amputation (TA) is blast wave induced fracture followed by limb avulsion from the blast wind, generating a transosseous amputation. Blast-mediated through-joint TAs were considered extremely rare with published prevalence <2%. Previous studies have also suggested that TA is frequently associated with fatal primary blast lung injury (PBLI). However, recent evidence suggests that the mechanism of TA and the link with fatal primary blast exposure merit review.
A trauma registry (UK Joint Theatre Trauma Registry) and postmortem CT (PM-CT) database were used to identify casualties (survivors and deaths) sustaining a blast-mediated TA in the 2 years from August 2008. TA metrics and associated significant injuries were recorded. Detailed anatomical data on extremity predebridement osseous and soft tissue injuries were only consistently available for deaths through comprehensive PM-CT imaging.
146 cases (75 survivors and 71 deaths) sustaining 271 TAs (130 in survivors and 141 in deaths) were identified. The lower limb was most commonly affected (117/130 in survivors, 123/141 in deaths). The overall through-joint TA rate was 47/271 (17.3%) and 34/47 through-joint injuries (72.3%) were through knee. More detailed anatomical analysis facilitated by PM-CT imaging revealed only 9/34 through-joint TAs had a contiguous fracture (ie, intra-articular involving the joint through which TA occurred), 18/34 had no fracture and 7/34 had a non-contiguous (ie, remote from the level of TA) fracture. No relationship between PBLI and TA was evident.
The previously reported link between TA and PBLI was not present, calling into question the significance of primary blast injury in causation of blast mediated TAs. Furthermore, the accepted mechanism of injury can't account for the significant number of through-joint TAs. The high rate of through-joint TAs with either no associated fracture or a non-contiguous fracture (74%) is supportive of pure flail as a mechanism for blast-mediated TA.
公认的爆炸介导的创伤性截肢（TA）机制是爆炸波导致骨折，随后肢体被爆炸风撕裂，造成经骨截肢。爆炸介导的经关节TA被认为极为罕见，已发表的患病率<2%。先前的研究还表明，TA常与致命的原发性爆震性肺损伤（PBLI）相关。然而，最近的证据表明，TA的机制以及与致命原发性爆炸暴露的联系值得重新审视。
使用创伤登记处（英国联合战区创伤登记处）和尸检CT（PM-CT）数据库，以识别2008年8月起的2年内遭受爆炸介导的TA的伤亡人员（幸存者和死亡者）。记录TA指标及相关的重大损伤。只有通过全面的PM-CT成像，才能始终如一地获得关于肢体清创时骨和软组织损伤的详细解剖数据，这些数据仅适用于死亡病例。
共识别出146例（75名幸存者和71名死亡者）遭受271次TA（幸存者130次，死亡者141次）的病例。下肢最常受累（幸存者中117/130，死亡者中123/141）。经关节TA的总体发生率为47/271（17.3%），47例经关节损伤中有34例（72.3%）发生在膝关节。PM-CT成像有助于进行更详细的解剖分析，结果显示，34例经关节TA中只有9例有连续骨折（即关节内骨折累及TA发生的关节），18/34没有骨折，7/34有非连续骨折（即远离TA水平）。PBLI与TA之间没有明显关系。
先前报道的TA与PBLI之间的联系并不存在，这使人质疑原发性爆震伤在爆炸介导的TA病因中的重要性。此外，公认的损伤机制无法解释大量的经关节TA。经关节TA中无相关骨折或非连续骨折的发生率很高（74%），这支持了单纯连枷机制是爆炸介导的TA的一种机制。
