Final answer:
The accompanying fracture to a calcaneus fracture from a jump is most likely in the lumbar spine due to the impact and force transmission through the kinetic chain to the lower back area.
Step-by-step explanation:
A person who experiences a alcaneus fracture after jumping and landing on his or her feet would most likely experience an accompanying fracture of the B. lumbar spine. When the body experiences a force from a hard landing, the calcaneus or heel bone is often the first to absorb the impact. Directly above in the kinetic chain, the vertebral column experiences the force transmission, particularly in the lower back that is the lumbar region. The thoracic spine is less likely to be involved due to the curvature and support provided by the rib cage. The coccygeal spine, which is the tailbone region, and the symphysis pubis, which is the joint in the front of the pelvis, are less likely to be involved in a hard landing injury from a jump