Pelvic injury patterns in blast: Morbidity and mortality

Abstract

BACKGROUND Pelvic trauma has emerged as one of the most severe injuries to be sustained by the victim of a blast insult. The incidence and mortality due to blast-related pelvic trauma is not known, and no data exist to assess the relative risk of clinical or radiological indicators of mortality. METHODS The UK Joint Theater Trauma Registry was interrogated to identify those sustaining blast-mediated pelvic fractures during the conflicts in Iraq and Afghanistan, from 2003 to 2014, with subsequent computed tomography image analysis. Casualties that sustained more severe injuries remote to the pelvis were excluded. RESULTS One hundred fifty-nine casualties with a 36% overall mortality rate were identified. Pelvic vascular injury, unstable pelvic fracture patterns, traumatic amputation, and perineal injury were higher in the dismounted fatality group (p < 0.05). All fatalities sustained a pelvic vascular injury. Pelvic vascular injury had the highest relative risk of death for any individual injury and an associated mortality of 56%. Dismounted casualties that sustained unstable pelvic fracture patterns, traumatic amputation, and perineal injury were at three times greater risk (relative risk, 3.00; 95% confidence interval, 1.27–7.09) to have sustained a pelvic vascular injury than those that did not sustain these associated injuries. Opening of the pubic symphysis and at least one sacroiliac joint was significantly associated with pelvic vascular injury (p < 0.001), and the lateral displacement of the sacroiliac joints was identified as a fair predictor of pelvic vascular injury (area under the receiver operating characteristic curve, 0.73). CONCLUSION Dismounted blast casualties with pelvic fracture are at significant risk of a noncompressible pelvic vascular injury. Initial management of these patients should focus upon controlling noncompressible pelvic bleeding. Clinical and radiological predictors of vascular injury and mortality suggest that mitigation strategies aiming to attenuate lateral displacement of the pelvis following blast are likely to result in fewer fatalities and a reduced injury burden. LEVEL OF EVIDENCE Prognostic, level III.

A New Understanding of the Mechanism of Injury to the Pelvis and Lower Limbs in Blast

“…Limb flail has been shown in an animal model to be linked to traumatic amputation (Rankin et al, 2019). However, the traumatic amputation rates seen in the animal study were far lower than what is seen in battlefield data (Rankin et al, 2019(Rankin et al, , 2020. When a pre-test crush was applied to the thigh causing soft tissue disruption, all mice subsequently sustained traumatic amputations following lower limb flail in simulated blast-wave conditions (Rankin et al, 2019).…”

“…Lower limb flail (tertiary blast injury) has been hypothesized to cause pelvic bony displacement following the initial fracture with subsequent displacement of the intrapelvic soft tissues causing pelvic vascular injury (Rankin et al, 2019). Military clinical data have shown that pelvic vascular injury occurs predominately at the posterior pelvis, with significant retroperitoneal bleeding (Rankin et al, 2020). It was identified as the injury with the single greatest risk of mortality in the dismounted pelvic blast injury casualty, followed by traumatic amputation (Rankin et al, 2020).…”

“…Military clinical data have shown that pelvic vascular injury occurs predominately at the posterior pelvis, with significant retroperitoneal bleeding (Rankin et al, 2020). It was identified as the injury with the single greatest risk of mortality in the dismounted pelvic blast injury casualty, followed by traumatic amputation (Rankin et al, 2020). Whilst not explored further in this study, traumatic amputation presents with vascular injury both at the zone closest to the blast (where widespread damage and anatomical destruction is present) and at a zone more proximal to this, with lacerations of small and large blood vessels.…”

“…It consists of traumatic amputation of at least one lower limb, a severe injury to another limb, pelvic, perineal and/or abdominal trauma, with extensive soft tissue damage (Ficke et al, 2012). Of the DCBI injuries described, battlefield data have shown pelvic vascular injury to be the single greatest predictor of mortality (Rankin et al, 2020). Post-mortem CT data have shown unstable pelvic fractures with lateral displacement of the sacroiliac joints to be the greatest predictor of vascular injury (Rankin et al, 2020).…”

“…Of the DCBI injuries described, battlefield data have shown pelvic vascular injury to be the single greatest predictor of mortality (Rankin et al, 2020). Post-mortem CT data have shown unstable pelvic fractures with lateral displacement of the sacroiliac joints to be the greatest predictor of vascular injury (Rankin et al, 2020). When these injuries are observed in combination with traumatic amputation and significant perineal injury, then the highest risk of mortality is seen (Rankin et al, 2020).…”