Describe the major differences in acute versus passive range of motion (rom) when distinguishing between an articular and nonarticular joint issue.

The question should be about active vs passive range of motion.

In the active range of motion, the test is done by asking the patient to move their body themselves. In this case, the patient should use their muscle to move their body. If there is a restriction in this examination, it could be caused by the muscles or the joints, or the nervous system that used to contract the muscle.
In the passive range of motion, the test is done by the examiner moving the patient body. Since no muscle used, the test shouldn't be influenced much by the muscle. Then, if there is an articular joint issue, the restriction would be found in both passive and active ROM, but the nonarticular joint issue might only cause abnormality in the active ROM.

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