Final answer:
The pathogenesis of quadriplegia in the beach chair/park bench position is related to spinal cord injury. The torque created by the upper body's center of gravity in front of the hips puts strain on the lower back muscles, leading to muscle strain and potential quadriplegia. Prolonged muscle action in this position can contribute to the development of quadriplegia.
Step-by-step explanation:
The pathogenesis of quadriplegia in the beach chair/park bench position is related to spinal cord injury. In this position, the upper body's center of gravity (CG) is in front of the pivot point in the hips, creating a clockwise torque around the hips. This torque puts strain on the muscles in the lower back, which need to exert large forces to counteract it. Prolonged muscle action in this position can lead to muscle strain and, in severe cases, quadriplegia.