In order to ensure patient safety when using a continuous passive motion machine, which instruction is most essential?

The most critical instruction for ensuring patient safety when using a continuous passive motion (CPM) machine is orientation to the remote on/off switch. This instruction is essential because it provides the patient or caregiver with the knowledge of how to quickly stop or adjust the machine if any discomfort or complications arise during use. The ability to operate the CPM machine safely is paramount, as it can minimize the risk of injury or adverse reactions that could occur if the patient experiences pain or if the machine malfunctions.

While the other options include important components of patient instruction, such as range of motion progression, proper stabilization straps, and post-treatment cryotherapy recommendations, they do not address immediate safety concerns like the ability to turn the device off. Therefore, familiarity with the remote on/off switch serves as a fundamental safety measure in the operation of a CPM machine.