Efficacy of Different Hair and Skin Decontamination Strategies with Identification of Associated Hazards to First Responders.

Background: Established procedures for mass casualty decontamination involve the deployment of equipment for showering with water (such as the ladder pipe system [LPS] and technical decontamination [TD]). This necessarily introduces a short, but critical delay. The incorporation of dry decontamination to the incident response process offers the potential to establish a more rapid and timely intervention. Objectives: To investigate the effectiveness of various dry (DD) and wet decontamination strategies for removing a chemical warfare simulant (methyl salicylate; MS) from the hair and skin of human volunteers. Methods: The simulant was applied to volunteers via whole body exposure to an aerosol. Three decontamination protocols (dry, LPS and technical decontamination) were applied, singly and in various combinations. The efficacy of the protocols was evaluated by fluorescent photography and analysis of residual MS from skin/hair swabs, decontamination materials and air samples. Results: Dry decontamination was effective, with the greatest reduction in skin and hair contamination arising from the "Triple Protocol" (DD+LPS+TD). Secondary hazards associated with contaminated individuals and equipment decreased as the number of decontamination procedures increased. In particular, dry decontamination reduced the potential contact and inhalation hazard arising from used washcloths, towels and vapor within the TD units. Discussion: The introduction of dry decontamination prior to wet forms of decontamination offers a simple strategy to initiate treatment at a much earlier opportunity, with a corresponding improvement in clinical outcomes and substantial reduction of secondary hazards associated with operational processes.

Evaluation of US Federal Guidelines (Primary Response Incident Scene Management [PRISM]) for Mass Decontamination of Casualties During the Initial Operational Response to a Chemical Incident.

STUDY OBJECTIVE: The aim of this study was to evaluate the clinical and operational effectiveness of US federal government guidance (Primary Response Incident Scene Management [PRISM]) for the initial response phase to chemical incidents. METHODS: The study was performed as a large-scale exercise (Operation DOWNPOUR). Volunteers were dosed with a chemical warfare agent simulant to quantify the efficacy of different iterations of dry, ladder pipe system, or technical decontamination. RESULTS: The most effective process was a triple combination of dry, ladder pipe system, and technical decontamination, which attained an average decontamination efficiency of approximately 100% on exposed hair and skin sites. Both wet decontamination processes (ladder pipe system and technical decontamination, alone or in combination with dry decontamination) were also effective (decontamination efficiency >96%). In compliant individuals, dry decontamination was effective (decontamination efficiency approximately 99%), but noncompliance (tentatively attributed to suboptimal communication) resulted in significantly reduced efficacy (decontamination efficiency approximately 70%). At-risk volunteers (because of chronic illness, disability, or language barrier) were 3 to 8 times slower than ambulatory casualties in undergoing dry and ladder pipe system decontamination, a consequence of which may be a reduction in the overall rate at which casualties can be processed. CONCLUSION: The PRISM incident response protocols are fit for purpose for ambulatory casualties. However, a more effective communication strategy is required for first responders (particularly when guiding dry decontamination). There is a clear need to develop more appropriate decontamination procedures for at-risk casualties.

Ligament origins are preserved in distal radial intraarticular two-part fractures: a computed tomography-based study.

Background Operative fixation of intraarticular distal radius fractures is increasingly common. A greater understanding of fracture patterns will aid surgical fixation strategy. Previous studies have suggested that ligamentous insertions may less commonly be involved, but these have included heterogeneous groups of fractures and have not addressed Lister's tubercle. Purpose We hypothesize that fracture lines of distal radial intraarticular 2-part fractures have reproducible patterns. They propagate through the cortical bone between ligament origins and do not involve Lister's tubercle. Methods Axial CT scans of two-part intraarticular distal radius fractures were assessed independently by two examiners. The fractures were mapped onto a grid and the cortical breaches expressed as a percentile of the total radial width or length. The cortical breaches were compared with the ligamentous insertions on the distal and Lister's tubercle. Associated injuries were also documented. Results The cortical breaches occurred between the ligamentous insertions in 85%. Lister's tubercle was not involved in 95% of the fractures. Three major fracture patterns emerged: radial styloid, dorsal, and volar. Each major pattern had two subtypes. Associated injuries were common. Scapholunate dissociation was associated with all types, not just the radial styloid fracture pattern. Conclusions The fracture patterns of two-part intraarticular fractures mostly involved the interligamentous zones. Three major groups were identified: dorsal, volar, and radial styloid. Lister's tubercle was preserved with fractures tending to propagate radial or ulnar to this structure. We suggest conceptualizing fracture fragments as osseo-ligamentous units to aid prediction of fracture patterns and associated injury. Study Design Diagnostic III Level of Evidence 3.

Arthroscopic assessment of avascular necrosis.

Avascular necrosis of the lunate is a process that is not well understood. The cause is uncertain, but a common theory persists that it is caused by disruption of the vascular supply to the lunate. This article discusses an approach to assessment that respects the articular cartilage and places at the front of the decision-making process the pathoanatomic components of the articular cartilage. It primarily respects the articular cartilage in the patient with avascular necrosis. This approach was developed for avascular necrosis of the lunate, but in principle applies to other joints with avascular necrosis as well.

An articular-based approach to Kienbock avascular necrosis of the lunate.

There are 3 pathologic phases of Kienbock disease: early vascular, intermediate osseous, and late chondral. Most of the earlier investigators have used Lichtman osseous radiologic classification. We have used an articular based approach to assess and manage Kienbock disease. The Bain and Begg arthroscopic classification is based on the number of nonfunctional articular surfaces of the lunate and adjacent articulations. The spectrum of articular changes span from grade 0, all normal articular surfaces; grade 1, involvement of the proximal lunate which is often soft and indentable with a false floor; grade 2a, lunate changes and secondary changes on the lunate facet; grade 2b, coronal lunate fracture produces involvement of the midcarpal joint; and grade 3s and 4, involvement of 3 and subsequently 4 of the perilunate articular surfaces. Arthroscopic findings have shown that radiographs often underestimate articular changes and frequently changed the treatment recommendation. Eighty-two percent of cases had at least 1 nonfunctional articulation, whereas 61% had at least 2 nonfunctional articulations. The aim of surgical treatment is to maintain functional motion with normal articulations. The articular-based classification directs treatment based on sound surgical principles. If all articular surfaces are intact, then a procedure that does not violate the articular surfaces is indicated (eg, synovectomy, vascularized bone graft, forage or joint leveling procedure). With nonfunctioning articular surfaces, an articular reconstructive procedure is required to leave the carpus mobile with only functional articular surfaces. (eg, proximal row carpectomy, radioscapholunate fusion, lunate replacement, or hemiarthroplasty). More extensive joint involvement requires a salvage procedure. This articular-based approach was developed for Kienbock disease but is universally applicable to all forms of avascular necrosis and can be used with advanced imaging modalities.

Sports-related injuries of the biceps and triceps.

Biceps or triceps ruptures are rare but can cause a significant disability. Surgical repair has become the preferred method of treatment for the complete rupture, but the decision when to treat partial tears is less clear. Reconstruction of the tendon is the preferred method when patients have a delayed presentation.

Axillary artery pseudoaneurysm after plate osteosynthesis for a clavicle nonunion: A case report and literature review.

Neurovascular complications have been reported from both plate osteosynthesis and intramedullary fixation of midshaft clavicle fractures. We wish to report a case of limb threatening ischemia from screw penetration of the axillary artery after plate osteosynthesis for a clavicle nonunion. A literature review of vascular trauma from midshaft clavicle fractures is presented.