Active vs. Passive Range of Motion: What’s the Difference?
Range of motion (ROM) describes how much movement is available at a joint. During a physical therapy evaluation, your therapist may assess both active range of motion (AROM) and passive range of motion (PROM). While they measure similar things, they provide different information about how your body moves. [1,2]
What Is Active Range of Motion?
Active range of motion is how far you can move a joint on your own.
For example, if your physical therapist asks you to raise your arm overhead, the movement you perform without assistance is your active range of motion.
AROM can be affected by factors such as muscle strength, motor control, pain, and joint mobility. Physical therapists may measure active movement with a goniometer and record the results to monitor changes throughout rehabilitation. [1,2]
What Is Passive Range of Motion?
Passive range of motion is how far a joint can move when an outside force moves it for you.
During a PROM assessment, your physical therapist moves the joint while you remain relaxed. This allows the therapist to assess available movement without requiring you to actively produce it. [1]
PROM can provide information about joint mobility and the flexibility of surrounding tissues. Comparing passive movement with active movement can also help your therapist better understand what may be contributing to a movement limitation. [1,2]
Why Measure Both?
The difference between active and passive range of motion can provide useful information during an evaluation.
For example, you may be able to actively raise your shoulder to 120 degrees, while your therapist can passively move it farther. That difference may help your therapist determine what factors could be limiting your active movement.
If both active and passive movement are restricted, your therapist may investigate other potential contributors, such as joint stiffness or limitations in the surrounding tissues.
However, range-of-motion measurements don't provide a diagnosis by themselves. Physical therapists consider ROM alongside strength, symptoms, movement quality, medical history, and functional abilities. [2,3]
How Is Range of Motion Measured?
A goniometer is one of the most common tools used to measure joint range of motion. It works similarly to a protractor and allows clinicians to measure joint angles in degrees. [1]
Consistent positioning and measurement techniques are important for making ROM measurements useful for comparison over time. [1,3]
The Bottom Line
The easiest way to remember the difference is:
Active ROM: You move the joint yourself.
Passive ROM: Someone or something else moves the joint for you.
Both measurements can give a physical therapist valuable information about how a joint is moving. If you've noticed a change in your mobility or are having difficulty moving a joint, a physical therapist can evaluate your movement and determine what factors may be contributing.
Whether you're experiencing mild discomfort or significant pain, our team at Buffalo Chiropractic & Physical Therapy is here to help. With various locations across Buffalo and WNY, we're ready to develop a personalized treatment plan and get you back to feeling your best. Contact us at (716) 892-8811 or visit our website to schedule your consultation.
Medical Disclaimer: This article is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. If you have concerns about your range of motion or physical function, consult a qualified healthcare professional.
References
- Goniometer. StatPearls. National Center for Biotechnology Information.
- Musculoskeletal Examination. StatPearls. National Center for Biotechnology Information.
- Gajdosik RL, Bohannon RW. Clinical measurement of range of motion. Physical Therapy. 1987;67(12):1867-1872.