The Injury Mechanism of Traumatic Amputation

High risk and low prevalence diseases: Blast injuries

INTRODUCTION

Blast injury is a unique condition that carries a high rate of morbidity and mortality, often with mixed penetrating and blunt injuries.

OBJECTIVE

This review highlights the pearls and pitfalls of blast injuries, including presentation, diagnosis, and management in the emergency department (ED) based on current evidence.

DISCUSSION

Explosions may impact multiple organ systems through several mechanisms. Patients with suspected blast injury and multisystem trauma require a systematic evaluation and resuscitation, as well as investigation for injuries specific to blast injuries. Blast injuries most commonly affect air-filled organs but can also result in severe cardiac and brain injury. Understanding blast injury patterns and presentations is essential to avoid misdiagnosis and balance treatment of competing interests of patients with polytrauma. Management of blast victims can also be further complicated by burns, crush injury, resource limitation, and wound infection. Given the significant morbidity and mortality associated with blast injury, identification of various injury patterns and appropriate management are essential.

CONCLUSIONS

An understanding of blast injuries can assist emergency clinicians in diagnosing and managing this potentially deadly disease.

Surface wave analysis of the skin for penetrating and non-penetrating projectile impact in porcine legs

Secondary blast injuries may result from high-velocity projectile fragments which ultimately increase medical costs, reduce active work time, and decrease quality of life. The role of skin penetration requires more investigation in energy absorption and surface mechanics for implementation in computational ballistic models. High-speed ballistic penetration studies have not considered penetrating and non-penetrating biomechanical properties of the skin, including radial wave displacement, resultant surface wave speed, or projectile material influence. A helium-pressurized launcher was used to accelerate 3/8″ (9.525 mm) diameter spherical projectiles toward seventeen whole porcine legs from seven pigs (39.53 ± 7.28 kg) at projectile velocities below and above V₅₀. Projectiles included a mix of materials: stainless steel (n = 26), Si₃N₄ (n = 24), and acetal plastic (n = 24). Tracker video analysis software was used to determine projectile velocity at impact from the perpendicular view and motion of the tissue displacement wave from the in-line view. Average radial wave displacement and surface wave speed were calculated for each projectile material and categorized by penetrating or non-penetrating impacts. Two-sample t-tests determined that non-penetrating projectiles resulted in significantly faster surface wave speeds in porcine skin for stainless steel (p = 0.002), plastic (p = 0.004), and Si₃N₄ ball bearings (p = 0.014), while ANOVA determined significant differences in radial wave displacement and surface wave speed between projectile materials. Surface wave speed was used to quantify mechanical properties of the skin including elastic modulus, shear modulus, and bulk modulus during ballistic impact, which may be implemented to simulate accurate deformation behavior in computational impact models.

Preliminary Considerations for Crime Scene Analysis in Cases of Animals Affected by Homemade Ammonium Nitrate and Aluminum Powder Anti-Personnel Landmines in Colombia: Characteristics and Effects

Simple Summary

Anti-personnel landmines are a major problem in countries that are subject to internal conflicts of a military or public order nature. They also continue to be a great threat to the population and biodiversity, even in post-conflict stages. Those most often used by armed groups are simple or homemade antipersonnel landmines that are designed without any type of technical regulations and standardized production systems. Their low-cost manufacturing and the use of easily accessible explosive substances for agricultural use, such as ammonium, have allowed their indiscriminate use, turning them into a huge public health problem. They are only detected when people or animals activate them, because they do not contain any materials that are detectable by traditional means. The scant literature on these artifacts focuses on injuries caused to humans, and only incidentally on field work. The objective of our study was to describe the behavior of a controlled explosion of a homemade antipersonnel landmine, and to verify the effects caused by the explosion on fauna and the environment. The results enable us to provide guidelines that may be implemented during field investigations, in which forensic veterinarians and related disciplines participate.

Abstract

During the armed conflict in Colombia, homemade improvised antipersonnel landmines were used to neutralize the adversary. Many active artifacts remain buried, causing damage to biodiversity by exploding. The extensive literature describes the effects and injuries caused to humans by conventional landmines. However, there is considerably less information on the behavior and effects of homemade antipersonnel landmines on fauna and good field investigation practices. Our objectives were to describe the characteristics of a controlled explosion of a homemade antipersonnel landmine (using ammonium nitrate as an explosive substance), to compare the effectiveness of some evidence search patterns used in forensic investigation, and to determine the effects on a piece of an animal carcass. The explosion generated a shock wave and an exothermic reaction, generating physical effects on the ground and surrounding structures near the point of explosion. The amputation of the foot in direct contact with the device during the explosion and multiple fractures were the main effects on the animal carcass. Finally, it was determined that finding evidence was more effective in a smaller search area. Many factors can influence the results, which must be weighed when interpreting the results, as discussed in this manuscript.

Risk and prognostic factors of replantation failure in patients with severe traumatic major limb mutilation

Purpose

Traumatic mutilation of major limbs can result in limb loss, motor disability, or death. Patients who had replantation failure needed to undergo additional surgeries (even amputation) and had a longer length of hospital stay. Here, we determined the risk and prognostic factors of replantation failure in patients with traumatic major limb mutilation.

Methods

This retrospective study included adult inpatients with severed traumatic major limb mutilation who underwent replantation from Suzhou Ruixing Medical Group from October 18, 2016 to July 31, 2020. Demographic, and clinical characteristics including traumatic conditions, laboratory findings, mangled extremity severity scores (MESS), treatments, and outcomes of the patients were collected. Data were used to analyze predictors and risk factors for replantation failure.

Results

Among the 66 patients, 48 (72.7%) were males, the median age was 47.0 years old. Replantation failure occurred in 48 patients (72.7%). The area under the curve of the joint prediction of lactic acid on admission, 72-h cumulative fluid balance, and albumin level immediately postoperatively was 0.838 (95% confidence interval [CI], 0.722–0.954; P < 0.001) with a sensitivity of 89.7% and a specificity of 69.2%. Lower limb trauma (odds ratio [OR] 8.65, 95% CI 1.64–45.56, P = 0.011), mangled extremity severity scores (OR 2.24, 95% CI 1.25–4.01, P = 0.007), and first 72-h cumulative fluid balance > 4885.6 mL (OR 10.25, 95% CI 1.37–76.93, P = 0.024) were independent risk factors for replantation failure.

Conclusions

Lower limb trauma, mangled extremity severity scores, and cumulative water balance were associated with replantation failure, implying that fluid management is necessary for major limb salvage. More studies are needed to explore the predictive power of indicators related to tissue oxygenation and wound healing for replantation failure.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00068-021-01876-w.

RISK-ORIENTED ANALYSIS OF LIMB LOSS IN VICTIMS OF MODERN HOSTILITIES

OBJECTIVE

The aim: Identification, verification and analysis of clinically effective risks of limb amputation as a basis for the formation of risk-oriented treatment and diagnostic tactics in victims with limb injuries due to modern hostilities.

PATIENTS AND METHODS

Materials and methods: This research is based on a study of 1,072 cases of limb damage due to modern hostilities in eastern Ukraine in 2014-2020. All injuries were gunshot (bullet and mine injuries). According to the concept of Clinical Risk Management, Clinical Result Risk was chosen for evaluation and analysis. Risk factors - epidemiological and anatomical signs of damage.

RESULTS

Results: Quantitative indicators of the clinical effective risk of limb loss are generally small and range from minimal to significant values (0.01-0.24). In some cases - up to 0.4 (significant), and are not critical and catastrophic. Of practical importance are only the risk factors associated with the nature of participation in hostilities and the anatomical characteristics of the injury. Among the immediate causes of limb loss, only primary traumatic amputation matters. Damage to vascular and nerve structures is not critical for limb loss. The impact of other risk factors may be reduced or eliminated if adequate care is provided.

CONCLUSION

Conclusions: The risks of limb loss in victims of modern hostilities vary within the qualitative characteristics of the minimum-significant risk. The greatest importance in the clinical implementation of risks are risk factors related to the performance of functional duties of servicemen and anatomical features. he use of risk-based analysis must be taken into account in the formation of standards of medical care and treatment protocols for victims of modern hostilities.