Final answer:
The radiographic examination of acromioclavicular joints is performed erect and can utilize weights to improve visualization, and should not be avoided if a dislocation or separation is suspected, as it helps in diagnosis and treatment guidance.
Step-by-step explanation:
The correct answer to the question "Which of the following is (are) true regarding radiographic examination of the acromioclavicular joints?" and the choices provided is C. 1 and 2 only. In practice, the procedure is indeed typically performed in an erect position because this allows gravity to assist in demonstrating the joint clearly. The use of weights can improve the demonstration of the joints by increasing the gravitational pull, hence separating the acromion and clavicle if there is a joint injury, thereby making any possible separation or dislocation more evident. It should be noted that while the procedure is relatively safe, if a dislocation or separation is strongly suspected, additional care must be taken to avoid further injury, but the radiographic examination itself should not be avoided as it is critical to confirm the diagnosis and guide treatment.