What injury should be suspected in a casualty presenting with lower back pain, pain radiating down their legs, and a hematoma on their back?

In the scenario presented, where a casualty exhibits lower back pain, leg pain radiating from that area, and a hematoma on the back, a spinal fracture should be suspected due to the specific combination of symptoms. The presence of a hematoma suggests potential trauma to the spine, which is a critical indicator that a fracture may have occurred.

Lower back pain can often indicate issues related to the spine, and when coupled with radiation of pain down the legs, it is suggestive of nerve involvement, which can happen when there is a fracture that compresses or irritates nearby nerves. In addition, the hematoma indicates localized bleeding, likely resulting from trauma, which often accompanies fractures.

While disc herniation and muscle strain can also present with lower back pain and leg pain, they typically do not lead to the presence of a hematoma unless there’s significant trauma. A pelvic fracture could also lead to symptoms that overlap in some respects, but the specific combination of lower back pain with a hematoma is more closely aligned with a spinal fracture, which necessitates appropriate evaluation and management to prevent further injury. Thus, the characteristics provided clearly align with the presentation of a spinal fracture.