What assessment method is commonly used to measure joint mobility?

Goniometry is the correct choice for measuring joint mobility because it involves the use of a goniometer, an instrument specifically designed to measure the range of motion (ROM) in joints. This method provides a quantifiable measurement that allows for the assessment of both active and passive movement in various joints. It is particularly valuable in clinical settings as it helps to determine limitations in joint motion, track progress after treatment, and establish functional goals for rehabilitation.

In contrast, palpation primarily involves feeling the joints and surrounding tissues for tenderness, swelling, or abnormalities, but does not provide precise measurements of joint mobility. Flexibility testing generally refers to a broader assessment of the musculotendinous units around a joint and may not isolate the specific joint motion being assessed. Manual muscle testing evaluates muscle strength and function, which, while important, does not directly measure the joint's range of motion. Thus, goniometry stands out as the most effective and specific method for assessing joint mobility.