Evaluation of gunshot injuries to long bones from pneumatic weapons using a human thigh model. Part II. Presentation and discussion of the detailed results of tests of gunshots of the anterior surface of the femur with 5.5 mm and 6.35 mm caliber shot.

Introduction: The development of pneumatic shooting has led to the construction of technologically advanced devices with discharge energies similar to those of firearms. The pneumatic weapons ammunition market offers a variety of shot which varies in penetration properties and the extent of gunshot damage. In view of the ease of "tuning" of air rifles, a study was conducted of the inlet damage to the anterior femoral surface after pneumatic gunshots. The paper shows the differences in damage parameters depending on the type of shot.

Material and methods: In the study, Air Arms Hi-Power Xtra FAC cal. 5.5 mm and FX Bobcat Mk II cal. 6.35 mm pneumatic carbines were used and lead shot by Haendler&Natterman's Spitzkugel type, Hollow Point and Baracuda cal. 5.5 mm and 6.35 mm, as well as lead-free shot Excite Apollo cal. 5.5 mm and Black Max Lead-Free cal. 6.35 mm. Measurements were taken of the extent of inlet damage to the anterior surface of the femoral shaft with X-ray and CT imaging.

Results: HollowPoint shot caused the greatest range of gunshot penetration damage in both bone and periosteum, Apollo lead-free shot caused the least. At the same time, HollowPoint shot showed the greatest susceptibility to ricocheting.

Conclusions: 1. The type of shot used influences diversified morphology of the holes and the nature of gunshot damage to the femoral shaft. The differences concern both the gunshot holes and the nature, course and extent of associated fractures. 2. The smallest inlet holes and damage to the periosteum with a regular shape are caused by gunshots with pointed and pointed tip pellets. The greatest extent of bone and periosteum inlet damage was observed in gunshots with Hollow Point type shot due to its predisposition to deformation and fragmentation. 3. Radio-imaging studies are a valuable complement to macroscopic visual assessment providing a useful value for identifying the type of shot used.