Experimental wounding models of different bullet types and diameters on extremities.

Abstract

Background: Gunshot wounds are the second leading cause of life-threatening injuries and frequently affect the extremities, accounting for 63% of combat-related cases over the past 50 years. Although extremity injuries have lower mortality rates, they still require urgent treatment to reduce complications. Wound ballistics studies often use tissue surrogates like ballistic wax and gelatin, which have limitations due to their dissimilarity to living tissues. There is insufficient data on the effects of gunshots on extremities composed of bone and muscle, which differ in resistance and elasticity. This study aims to analyze the damage caused by commonly used ammunition in living tissue and provide healthcare professionals with critical insights to improve emergency care.

Methods: The study involved six Adana-breed sheep, aged 3-4 years, previously used in another study and showing no vital signs. Ethical approval was obtained from the local ethics committee. Test shots were conducted using 9×19 mm (M822), 5.56×45 mm (SS109), and 7.62×51 mm (M80) bullets from a distance of 300 cm, targeting the front legs of sheep positioned laterally. Following the shots, entry and exit wounds were photographed, and anteroposterior and lateral X-ray images of the extremities were taken for analysis. The aim was to examine the effects of different types of ammunition on extremities and provide insights into the characteristics of gunshot wounds.

Results: In the first test group (subjects A and B), X-ray imaging revealed joint integrity loss, multi-part fractures, and cavitation in the soft tissue, with bone fragments distributed along the exit trajectory. No bullet fragments were found within the wound cavity. The M822 bullet produced a typical entry wound and a smaller, more defined exit wound. In the second group (subjects C and D), SS109 bullets caused fragmentation of bone, muscle, tendon, and skin. Bullet fragments created a shrapnel-like effect. The exit wounds were larger and had irregular edges. In the third group (subjects E and F), M80 bullets caused extensive tissue disruption due to their high kinetic energy. The resulting exit wounds were wide and irregular.

Conclusion: This study found that M80 bullets caused the most severe bone and soft tissue damage compared to M822 and SS109 bullets, primarily due to their higher kinetic energy density and structural characteristics. Unlike prior research using synthetic tissue models, this study demonstrates the real-tissue effects of different ammunition types. Radiologists, forensic medicine experts, and other healthcare professionals should be aware that firearm injuries vary depending on the bullet's characteristics. Applying this understanding can lead to appropriate diagnoses and improved treatment strategies, ultimately enhancing patient outcomes.