Final answer:
A Chance fracture is a serious spinal injury involving horizontal splitting of the vertebrae due to flexion-distraction forces, often sustained in motor vehicle accidents with the use of a lap belt. The biomechanics include both compression and flexion, and treatment varies based on severity.
Step-by-step explanation:
A Chance fracture is a type of spinal injury resulting from high-energy trauma that causes flexion-distraction forces on the spine. This fracture involves a horizontal splitting through the vertebrae and surrounding structures, often at the thoracolumbar junction. In a Chance fracture, the posterior elements, intervertebral disc, and anterior elements of the spinal column are all disrupted. This mechanism of injury typically occurs when a person is wearing a lap belt during a motor vehicle accident and their upper body is thrown forward while the lower body is restrained.
The biomechanics of a Chance fracture involve a combination of compression and flexion forces that pull the bone segments apart. The injury may be associated with abdominal injuries due to the same force causing pressure against the lap belt. Treatment often involves closed reduction or open reduction, depending on the severity and complexity of the fracture. Proper stabilization and realignment of the spine are critical for healing and prevention of neurological deficits.