Question

why does range of motion need to be measured separately for each joint?
a: the average ranges of motion of joints are not known.
b: each joint has a different range of motion.
c: range of motion can change rapidly in a joint.
d: none of the above

please select the best answer from the choices provided.

○ a
○ b
○ c
○ d

Explanation:

To determine the answer, we analyze each option:

• Option A: Average ranges of motion for joints are known (e.g., normal ranges for knee, elbow, etc.), so this is incorrect.
• Option B: Each joint (e.g., shoulder vs. wrist) has a unique structure and function, leading to different ranges of motion. This explains why each joint's range must be measured separately.
• Option C: While range of motion can change, the primary reason for separate measurement per joint is their inherent different ranges, not rapid change. So this is not the main reason.
• Option D: Since B is correct, D is incorrect.

Answer:

B. Each joint has a different range of motion.