Final answer:
The close-packed position of the iliofemoral (hip) joint is when the joint is in extension with the surrounding ligaments taut, providing maximal joint congruence and stability while standing.
Step-by-step explanation:
The close-packed position of the iliofemoral (hip) joint refers to the position where the joint structures are maximally congruent and the ligaments and capsule are taut. This occurs when the hip joint is in extension, with the thigh in a vertical alignment, pulling the head of the femur tightly into the deepened socket of the acetabulum. The iliofemoral ligament, along with the pubofemoral and ischiofemoral ligaments, provide strong support in this upright, standing position, stabilizing the hip joint and bearing the weight of the body with minimal muscle effort.