Conventional weapons and explosives continue to be the most commonly employed instruments of destruction by terrorists worldwide. Such attacks are occurring with increasing frequency and ferocity. The effects of bombings and blast injuries are both physically and psychologically devastating. Explosions combine four mechanisms of injury. In addition to these causes of injury and death, crush injury, entrapment, and compartment syndrome magnify the devastation of blast trauma. By recognizing the unique features of blast injuries and by prioritizing mass casualties to provide maximal benefit for the greatest number of patients, the physician will be better equipped to triage and stabilize these victims.

[Ann Emerg Med. 2009;53:425.] A 26-year-old man presented to the emergency department with a chief complaint of a right knee injury sustained shortly before admission. He flipped his bicycle and struck his right knee on a rock, sustaining a laceration. The patient described a gush of fluid from the laceration when he attempted to stand, and he was unable to walk because of severe knee pain. Physical examination revealed a 3-cm transverse laceration of the distal anterolateral right thigh, approximately 8 cm proximal to the patella. The knee examination showed tenderness in the peripatellar areas, no effusion, normal but painful range of motion, and normal neurovascular and tendon exams. Knee radiograph results were negative for bony abnormalities, foreign body, or intraarticular air. Methylene blue was instilled into the joint through a medial approach, and it extravasated from the laceration (Figure 1, Figure 2).Figure 2Lateral view, methylene blue arthrogram, right knee. Used with permission of David M. Lemonick, MD, Emergency Department, Highlands Hospital, Connellsville, PA.View Large Image Figure ViewerDownload Hi-res image Download (PPT) The knee is the major joint most frequently involved in open joint injuries.1Carr N.J. Gallico G. Soft tissue injuries and management about the knee.in: Siliski J.M. Traumatic Disorders of the Knee. Springer-Verlag, New York, NY1994: 62Google Scholar In the civilian setting, gunshot wounds and motor vehicle crashes are responsible for the majority of these wounds. An open joint may result from direct penetration of the joint or by extension into the knee of a compound periarticular fracture. Knee dislocations are open in 20% to 30% of cases.1Carr N.J. Gallico G. Soft tissue injuries and management about the knee.in: Siliski J.M. Traumatic Disorders of the Knee. Springer-Verlag, New York, NY1994: 62Google Scholar Any deep wound in proximity to a joint should be suspected of being an open joint injury. Detection of an open joint may be immediately evident on inspection of the wound, or it may be subtle, requiring adjunctive testing. The criteria for making the diagnosis include a visible or palpable opening into the joint, air or foreign bodies in the joint on radiographic examination, or saline solution extravasation through the wound on arthrocentesis.2Mandavia D. Newton E.J. Demetriades D. Color Atlas of Emergency Trauma. Cambridge University Press, Cambridge, England2003Crossref Google Scholar In questionable cases, methylene blue may be added to the arthrocentesis irrigant. Initial treatment requires meticulous debridement of the wound and broad-spectrum antibiotics. All major open joint injuries require formal operative joint exploration and irrigation.2Mandavia D. Newton E.J. Demetriades D. Color Atlas of Emergency Trauma. Cambridge University Press, Cambridge, England2003Crossref Google Scholar

We present a case of acute torsion of the gallbladder in a young woman. Approximately 400 cases have been reported since 1898, mostly in elderly women, and the incidence appears to be increasing. The anatomy and pathophysiology that predispose patients to this rare surgical emergency are discussed. Several clinical and imaging findings can be used to distinguish gallbladder torsion from typical acute cholecystitis. By recognizing and treating gallbladder torsion early in its course, a low surgical morbidity and mortality can be achieved. The case presented highlights for emergency physicians some of the considerations in identification of patients with acute cholecystitis who are at highest risk of gangrene and perforation, their emergency treatment, and the timing of surgery.

potentially life-threatening infection of the neck and the floor of the mouth (Table 1). Originally described by Wilhelm Frederick von Ludwig in 1836,1 this condition is notorious for its aggressiveness, rapid progression to airway compromise, and high mortality when not treated promptly.2–6 This article discusses the pathophysiology, clinical manifestations, diagnosis, and treatment of this dangerous condition. Two cases are described to illustrate typical presentations of the disorder.