Prone Instability Test

What is the Prone Instability Test?

Lumbar Instability is a state in which the lumbar spine has a greater-than-normal range of motion. If a patient has lumbar instability, this means there is abnormal and excessive movement in their vertebrae.

This is not good because this could lead to degenerative problems if left untreated for too long. Those with lumbar instability risk having their lumbar spine degenerating to the point they might not be able to support their own weight. This will severely impact the quality of living and prevent the person from performing daily activities without support.

So, if your patient attends their consultation and complains of lower back pain, consider performing the Prone Instability Test. This test is a physical examination procedure that aims to assess the patient's lumbar region for signs of instability or abnormal movement patterns. The test will have the patient assume a certain position, and they will need to maintain it for a few seconds. Depending on whether they can maintain this position or not, and if they feel pain then they test positive, there is a possibility that their lumbar spine is compromised.

Have a look at this video to see how the Prone Instability Test is performed:

How do you conduct the Prone Instability Test?

You're probably thinking, “So, what is this position?” We'll get to that in a moment because it's time to discuss the specifics of the Prone Instability Test, specifically how to conduct it.

Before you do anything, the one thing that you have to prepare is a comfortable examination table or bed. This test requires the patient to assume a prone position. Once you have this ready, do the following (but demonstrate all of this first):

• Have your patient assume a prone position on the examination bed or table. They won't be completely lying down. They should just lean on it to place only their upper half on the bed or table. Their legs must be over the edge of the bed or table, and their feet must be resting on the floor.
• Once they are prone and leaning on the examination bed or table, you will position yourself to the patient's side by their lumbar area.
• Once you're in position, you will do a spring test on the lumbar spine. This means you will apply downward pressure on the lumbar area until you can locate the spot where the patient feels pain.

• Tell the patient to tell you if they are in pain while you are locating the painful spot.
• Once you have located the painful spot, have your patient lift their legs off the floor while leaning on the examination bed or table.
• Have them maintain their position for 5 to 10 seconds. They are allowed to grab hold of the bed or table to maintain their position.

And those are the steps on how to properly conduct the Prone Instability Test.

How to interpret the findings of the Prone Instability Test

To determine the diagnostic accuracy of the results of the Prone Instability Test, you need to take note of the painful spot you located by performing the spring test on the lumbar spine area.

‍Positive test result

Once the patient raises their legs and maintains their position, ask them if they feel the same pain while keeping their legs raised. If their pain subsides while maintaining this position (active position), but they feel all of it when they place their feet back on the floor, then this test is positive.

‍Negative test result

They are negative if they don't feel pain in both the resting and active positions. They are still negative if they feel pain in both positions because the Prone Instability Test checks if the pain subsides when the patient assumes the active position. If that's the case, they may have other problems concerning spinal stiffness in their lower back.

If they provoke pain and are positive, the next step is to endorse them for further examination so that other tests can be conducted. Even with a positive designation, it doesn't mean that the problem is 100% lumbar spine instability. It might be a different problem, so other tests will help you confirm it. If they are negative but feel pain, endorsing them for further examination is still the best option.

When is it best to conduct the Prone Instability Test?

If a patient shows up for an appointment and tells you about pains in their lower back or recurrent chronic lower back pain, that's the best time to tell them you will perform the Prone Instability Test. Remember that lumbar spine instability can lead to the degeneration of the lumbar spine if left untreated for too long, so it's best to conduct this as soon as possible so that the problem can be addressed and managed immediately before it gets any worse to the point that it will severely impact the patient's quality of life.

The Prone Instability Test is, more often than not, included as part of a comprehensive examination. This is because it should not be used as the sole assessment to determine the actual problem of a patient's lower back.

That's not to say that the test is unreliable. It is because it can determine if lumbar shear instability is the problem based on a certain factor, but that doesn't necessarily mean that it's just lumbar spine instability. There might be more to the patient's lower back. Other tests, especially imaging tests, will help determine if lumbar spine instability is the actual problem and if the patient has other lower back problems.

Who can conduct the Prone Instability Test?

Since the Prone Instability Test is meant to assess patients with lower back problems and it is essentially a physical examination technique, the best healthcare professionals that can perform this test are those who have been highly trained to assess, diagnose, and treat musculoskeletal problems, especially in the lumbar area. These professionals would be:

• Orthopedists
• Physical therapists
• Occupational therapists
• Physiotherapists
• Chiropractors
• Rehabilitation specialists

These professionals specialize in treating such problems and are trained to properly execute physical examination techniques so their designations are, more or less, on the mark. They also have a grasp of other tests that should be conducted based on the Prone Instability findings, and they can properly analyze positive test results and determine the best treatment that the patient needs.

It is best to leave the execution of the Prone Instability Test to the experts, even if the instructions seem easy. This test should be restricted to them because they know how to conduct it safely.

Since this test involves pain, professionals will be able to perform the spring test easily and apply the necessary amount of pressure necessary to elicit the pain, and then they can provide support if needed during the part where the patient has to raise their legs. If performed incorrectly or if too much pressure is applied, the possible pre-existing condition that the patient has might get aggravated or worsen. So, it's best to leave it to the experts.

What are the benefits of the Prone Instability Test?

It's an inexpensive test to conduct

The Prone Instability Test is a physical examination technique that requires nothing except a comfortable examination bed or table and your own two hands. The instructions are also simple, so conducting shouldn't be difficult. Whatever difficulty will be on the part of the patient, specifically during the part where they have to lift their legs. The possible back problem that they might have could affect their capability to lift their legs while their upper body is in a prone resting position on the bed or table.

This test is also a good choice for professionals who are swamped with work most of the time. It can be accomplished between 1 to 5 minutes.

It can be used to educate patients about lumbar spine instability

While this was originally designed to assess lumbar spine instability, this technique can also serve as a way to educate patients about lumbar spine instability and why they should maintain good posture as well as proper body mechanics to keep the lumbar spine from developing instability.

By educating the patient, they might feel compelled to make the necessary changes they need for their lifestyle to prevent them from developing lumbar spine instability. This can be done during rehab, too!

It can be used to create a plan to help manage the lumbar instability

Speaking of educating the patient, the Prone Instability Test can help identify patients who are at risk of developing lumbar spine instability. Suppose this and other tests confirm that patients are developing lumbar spine instability early. In that case, healthcare professionals have the opportunity to come up with a care plan that includes a stabilization exercise program that the patient can follow to help curb the problem, prevent it from getting worse, and restore the lumbar spine to a better condition.

It can be used to monitor the patient

Not only can this test help guide treatment decisions, but it can also be used to monitor the patient down the line. If you develop and implement a care/treatment plan, then naturally, you'd want to know if it actually works. You can find out by having your patient attend a routine check-up and repeat this test. If there is less pain than before or if it's completely gone, your treatment plan must be effective because the patient is getting better. If the pain is the same or is somehow worse, then that's a sign that you should adjust your treatment plan or overhaul it.