The most common mechanism of injury among U. S. soldiers in the Iraq/Afghanistan war are explosions, and the worldwide frequency of explosive events by improvised explosive devices (IEDs) due to terrorist attacks has markedly increased over recent years.

　　Blast injuries are complicated, involving the compounding of blunt injuries, penetrating injuries, and injuries by blast waves. Blast physics and pathophysiology should be understood to provide medical care for blast injuries, especially for blast lung injury (BLI), and blast-induced traumatic brain injury (bTBI). Safety and security are the highest concerns when providing medical care at the scene of the event.

　　Japanese “Survival cards for first responders at the scene of explosive events, and for medical staff providing prehospital and hospital medical care”, and “medical records of blast injuries” have been created, referring to the guidelines proposed by the United States and European countries. In Japan, guidelines to treat blast injuries must be established, and we must further promote our preparedness to handle such injuries by implementing full-scale drills.

　　Recently, scoring systems for early prediction of the necessity of massive transfusion have been reported. We investigated the accuracy of such scoring systems in multiple trauma patients. In this study, 32 patients required massive transfusion and 101 patients did not. For trauma-associated severe hemorrhage (TASH) score and assessment of blood consumption (ABC) score, the area under receiver operating characteristic (AUROC) values was 0.819 and 0.711, respectively. Therefore, TASH and ABC score were moderately accurate. The AUROC values for TASH score in young patients under 65 years of age and old patients more than 65 years of age were 0.976 and 0.753, respectively. TASH was higher accuracy in predicting the necessity of massive transfusion in young patients than in older patients, in whom physiological signs are more difficult to detect.

　　We recently encountered a child with cervical cord injury without bone lesion. The patient was an 11-year-old boy. During physical exercise, his neck transiently became intensely extended. Despite the absence of an evident injury on external examination, the child began to complain of neck pain and muscular weakness developed in both arms and the right leg. He was therefore brought to a local clinic. At that time, MRI of the cervical spinal cord did not detect any abnormalities. The patient was referred to our hospital to receive a more detailed examination. On admission day 2, muscular weakness of the left leg and an increase in leg tendon reflex developed. Cervical cord MRI was carried out again, demonstrating cervical cord lesions at the C3-C7 levels without being accompanied by any evident bone lesion. Patients with cervical cord injury sometimes do not present any significant abnormalities on diagnostic images taken immediately after injury despite the presence of signs of neurological abnormalities. As in the case of elderly patients, careful follow-up is necessary when dealing with injured children if the possibility of cervical cord lesions cannot be ruled out after considering the mechanism of injury.

　　We encountered a 64-year-old male with laryngeal injury sustained in a traffic accident. CT showed thyroid cartilage fracture and surrounding hematoma. Neither dyspnea nor hoarseness was observed. After about 4 hours, CT was performed again, which demonstrated slight compression and narrowing of the airway, suggesting airway obstruction. Endotracheal intubation was performed to maintain the airway patency. He subsequently underwent tracheotomy and thyroid cartilage reconstruction. His postoperative course was favorable, and he was discharged. In this patient, although there were few symptoms suggesting airway obstruction, preventive endotracheal intubation was performed based on CT findings, and a favorable result was obtained. In patients with laryngeal injury, evaluation and management of the airway should be the first priority even if there are few symptoms, and follow-up not only by physical examination but also by imaging techniques is necessary.

　　We present a case of hepatic artery pseudoaneurysm that developed following blunt hepatic trauma that had been treated without surgery. The patient was a 12-year-old boy who sustained a bicycle handle-bar injury and was transferred to our hospital. The initial computed tomography (CT) scan showed a complex deep hepatic injury, but there was no apparent vascular injury. The patient was hemodynamically stable and managed without surgery. The clinical course was stable, but a follow-up abdominal CT scan taken on day 8 showed a hepatic artery pseudoaneurysm. The patient went into shock soon after CT was performed. Emergency angiography demonstrated active extravasation. He was treated with transarterial embolization and discharged on day 20. We reevaluated the initial CT scan and noted minor vascular injury. Careful evaluation of initial CT scans to identify minor vascular injury is strongly recommended in patients with complex deep hepatic injuries that have been treated without surgery.

　　The patient was a 41-year-old male who sustained abdominal injury during a traffic accident in the mountains. A doctor-helicopter was requested because the patient was in shock (BP<90), and was able to land near the scene of this accident, which was about 100 minutes from the hospital by land transportation. The patient's vital signs were stabilized by rapid fluid therapy, and he was transported to the ER about 20 minutes later. FAST (Focused Assessment with Sonography for Trauma) became positive and then blood pressure was decreased again following an emergency blood transfusion. CT demonstrated liver injury and perforation of the digestive tract. The patient was transferred to the operating room, where he underwent hepatorrhaphy, ligation of a tear in the gastroduodenal artery, and simple closure of a perforation at the first portion of the duodenum. Thereafter, the patient was transferred to a local hospital 16 days after the injury, and his postoperative course was satisfactory.

　　A 34-year-old female sustained multiple traumatic injuries in a traffic accident and was transferred to a nearby emergency hospital. She was diagnosed as having thoracic and abdominal injuries and an open fracture of the right femur, and treated in the intensive care unit. The patient was then discharged from the hospital two weeks postoperatively. Subsequently, she gradually developed pain in her right femur and could not walk well because of the pain. She consulted our hospital six months postoperatively.

　　At the initial consultation, she demonstrated severe right knee contracture and other problems with her right leg. A radiograph showed extensive defect of the center of the right femur. Fortunately, bone union was achieved after several operations, and we could achieve a curative stage for the difficult-to-cure osteomyelitis and extensive bone defect. However, it is very important to consider the treatment strategy during primary trauma management in order to prevent preventable trauma-related disability.