Final answer:
Unilateral rib fractures with same-sided unilateral flail chest should be coded separately. The correct option is 2.
Step-by-step explanation:
Coding should be done separately for unilateral flail chest with same-sided unilateral rib fractures. A rib fracture occurs when one or more ribs are broken or cracked. Flail chest refers to a condition where a segment of the rib cage is disconnected from the rest, leading to paradoxical movement during breathing.
The two conditions are distinct and should be coded separately to accurately reflect the patient's injuries and aid in appropriate treatment and billing. Hence, 2 is the correct option.