Following an explosion, a patient is trapped in a collapsed structure and suffers crush injuries to both lower extremities. How would the injuries be classified based on the blast-injury phase?

In the context of blast injuries, the classification of injuries based on the blast-injury phase provides insight into the mechanism and nature of the injuries sustained. When considering a situation where a patient is trapped in a collapsed structure and suffers from crush injuries to both lower extremities, these injuries fall into the category of tertiary blast injuries.

Tertiary blast injuries occur when a person is propelled by the force of the blast wave, leading to potential collisions with structures or debris. In this case, the explosion's pressure wave could result in the person being thrown against the ground or surrounding objects, resulting in crush injuries. The fact that the patient is trapped under debris also implies that the force of the explosion caused an environment where the patient experienced significant structural collapse, further contributing to these injuries.

Primary blast injuries are typically those that are caused by the direct effects of the blast wave itself, such as air embolism or tympanic membrane rupture, while secondary blast injuries result from shrapnel and debris that are propelled by the blast. Neither of these directly applies to the crush injuries sustained from the collapse of the structure due to the explosion's aftermath. Similarly, the classification "none of the above" doesn't accurately capture the nature of the injuries sustained.

Thus, class