"Active range of motion" and "passive range of motion" (PROM) are two terms prominently used in the fitness and rehabilitation space. Both types of motion involve improving the joint's range of motion; however, the actual method of doing so is different.

If a person physically moves or stretches a part of their body, such as a leg, it is known as a passive range of motion. In such a scenario, physical therapy is provided if the person finds it hard and can't make any effort.

In layman's terms, if you cannot actively perform range-of-motion exercises, a partner can assist. This kind of motion is commonly seen in the rehabilitation field. A machine or therapist will work to increase a person's range of motion to their pre-injury baseline.

This article explores the definition of passive range of motion, how it differs from active range of motion, examples of PROM exercises, and its critical role in improving joint health and preventing immobility.

What is Passive Range of Motion (PROM)?

Passive Range of Motion (PROM) refers to the movement of a joint through its natural range, performed entirely by an external force without any active effort from the individual. In other words, a therapist or caregiver moves the limb or joint while the person remains completely relaxed. PROM is particularly beneficial for individuals who are unable to move a specific joint themselves due to injury, surgery, or a medical condition.

This type of movement is essential in preventing joint stiffness, maintaining flexibility, and aiding in the recovery process. Unlike active range of motion, where the person uses their own muscle strength to perform movements, passive range of motion relies on outside assistance, making it a key component in early-stage rehabilitation.

Do you know? A goniometer measures the angles of joint movement during range of motion assessment.

Difference Between Active and Passive Range of Motion

Understanding the distinction between active and passive ROM is crucial for selecting appropriate exercises during physical therapy. In active ROM (AROM), the individual performs movements using their own muscles. This is often seen in exercises where the person raises their arm, bends their knee, or stretches without any external help.

On the other hand, in passive ROM, the movement is executed by a therapist, machine, or another person, and the muscles of the affected joint remain inactive.

Comparison Table: Active vs Passive ROM

Benefits of Passive Range of Motion

PROM plays a significant role in therapeutic and clinical settings. Some of its key benefits include:

1. Prevents Joint Stiffness: Regular movement helps maintain joint fluidity and reduce stiffness, especially in immobile patients.
2. Maintains Flexibility: Even if a patient can't move a joint, PROM helps retain the joint's full movement capacity.
3. Improves Circulation: Movement promotes blood flow, which can aid in healing and reduce swelling.
4. Prevents Muscle Shortening: Prevents conditions like passive insufficiency, where a muscle becomes too short to function properly.
5. Reduces Pain and Discomfort: Gentle PROM exercises can reduce pain by improving lubrication and decreasing inflammation.

Examples of Passive Range of Motion Exercises

PROM exercises are typically administered by physical therapists or caregivers, and they can be performed on various joints. Here are some examples:

These exercises help in restoring or maintaining joint mobility, particularly in individuals recovering from surgeries, such as joint replacements, or those suffering from neurological impairments like strokes.

When We Use Passive Range of Motion?

When do we actually use passive range of motion? Well, if you’re dealing with an injury or just trying to stay ahead of stiffness, it’s super helpful. According to the CDC, over 54 million Americans suffer from some form of arthritis, and passive range of motion (PROM) is often used as a preventive therapy to fight off stiffness and improve day-to-day function.

If you’ve ever hurt your knees, neck, shoulder, hips, or really any particular body part that has a joint, you know just how quickly your range of motion can get affected. That’s because joint movement—the distance and direction your joint can move—gets limited after an injury or trauma.

To figure out exactly what’s going on with a joint, a physical therapist, doctor, or another qualified health professional usually measures the amount of joint movement during a physical exam. This can happen right after an injury or as part of an active rehabilitation program. Here’s what you should know:

• Motion refers to how freely a joint can move.
• Limited motion can be improved with motion exercises like:
  
  • Active range exercises
  • Active assistive range exercises
  • Passive range of motion exercises
• These exercises also help strengthen the surrounding muscles and support better recovery.

Sometimes, a physical therapist, personal trainer, or health coach might bring in passive range of motion exercises during a training session to boost mobility and athletic performance.

You might also see active assistive range exercises being used, where a partner helps guide the movement—especially common in:

• Partner-assisted stretching
• Athletic training sessions
• Group rehabilitation programs

Do you know? Active range of motion is important because it is associated with daily activities.

When and Why to Use Passive Range of Motion

PROM is particularly useful in the following scenarios:

• Post-Surgical Recovery: Especially after procedures like knee or hip replacements, where initial movement is restricted.
• Neurological Conditions: Such as stroke, spinal cord injury, or multiple sclerosis, where voluntary muscle control is impaired.
• Immobilized Patients: Individuals who are bedridden or in a coma benefit greatly from PROM to avoid complications like joint contractures.
• Pain Management: Gentle PROM can alleviate discomfort and promote relaxation.

The goal of PROM is not to build strength but to maintain the functionality and structure of the joint and surrounding tissues.

Tools & Equipment Used in Passive Range of Motion

In addition to manual therapy provided by caregivers or physical therapists, various tools and devices assist in delivering Passive Range of Motion effectively:

• Continuous Passive Motion (CPM) Machines: These devices automatically move joints through a controlled range, often used post-surgery for the knee or shoulder.
• Slings and Supports: Used to aid in the gentle movement of limbs.
• Resistance Bands and Pulleys: Sometimes used to guide limbs through motion without muscle activation.

PROM Device Usage Table

Key Terms and Definitions

• Passive Range of Motion (PROM): Movement performed on a joint by an external force without active participation.
• Active Range of Motion (AROM): Movement performed by the individual using their own muscles.
• Passive Movement: Movement of a joint with external assistance.
• Continuous Passive Motion (CPM): A device-driven method to keep joints in motion.
• Passive Insufficiency: A condition where a muscle cannot lengthen enough to allow full range of motion.
• Range of Motion (ROM): The full movement potential of a joint.

Conclusion

Passive Range of Motion is a cornerstone in the realm of physical therapy and rehabilitation. It allows individuals with limited mobility to maintain joint health, reduce pain, and prepare for more active movement when possible. Understanding the differences between active and passive range of motion and incorporating appropriate exercises can greatly enhance recovery outcomes.

Whether recovering from surgery, managing a neurological condition, or caring for a bedridden patient, Passive Range of Motion offers a valuable, science-backed approach to maintaining movement and function. With the right guidance and consistency, it plays a vital role in improving quality of life and promoting long-term mobility.

Frequently Asked Questions (FAQs)

What is the difference between active and passive range of motion?
Active ROM is performed by the individual using their muscles, while Passive Range of Motion is done by an external force without muscle engagement.

Can PROM help with flexibility?
Yes, PROM maintains and sometimes improves joint flexibility, especially in immobile patients.

Are passive movements painful?
When performed correctly, passive movements should not be painful. They are meant to be gentle and therapeutic.

How often should Passive Range of Motion exercises be done?
This depends on the individual's condition, but typically 1–2 times daily under the supervision of a therapist.

What equipment is used for PROM?
PROM can be performed manually or with equipment like continuous passive motion machines.

How can I improve my active range of motion?
You can improve your active range of motion by holding movements or stretches for at least 30 seconds. Stretching is especially effective when done before an activity or exercise, helping to warm up the muscles and prepare the joints for better mobility.

Can PROM exercises improve mobility in the long run?

Yes, passive range of motion exercises help improve mobility over time, especially when combined with a personalized treatment plan designed by a healthcare provider or physical therapist. PROM keeps joints moving, which is key to preventing stiffness and maintaining overall health.

Is PROM helpful for someone with a limited range of motion in the leg or elbow?

Absolutely. PROM is commonly used when a person has a limited range in joints like the leg, elbow, or shoulder. These exercises help restore joint movement with minimal effort from the individual, making it ideal during early rehab stages.

Does PROM contribute to better circulation and joint health?

Yes! Even when performed passively, movement helps stimulate circulation, which delivers nutrients to joints and muscles. This supports joint movement, reduces swelling, and can even help manage pain.

Can PROM be used to transition into active range of motion exercises?

Definitely. PROM is often the first step in rehab when a body part can't move independently. Over time, it prepares the joint for active range of motion, helping the individual improve strength and move toward more independent activity in an upright position.

Key Takeaway

• Passive range of motion improves mobility and supports circulation.
• Passive range of motion may prevent contractures and skin pressure ulcers.
• One of the main goals of rehabilitation is to prevent long-term decrease in overall range of motion.
• Passive range-of-motion exercises stimulate blood flow, which is crucial for recovery.
• Measuring range of motion can help track progress during rehabilitation from surgery or injury.
• Active ROM is usually less than passive ROM.