Valsalva Maneuver: Screening for Intrathecal Pressure

The Valsalva Maneuver is a simple screening test used to detect space-occupying lesions in the spinal canal, such as herniated discs. It works by increasing the pressure inside the spinal cord (intrathecal pressure).

1. Purpose

The primary purpose of the Valsalva Maneuver in orthopedics is to **test for** increased intrathecal pressure (pressure within the spinal canal). It helps detect space-occupying lesions such as herniated discs, tumors, or osteophytes that may be compressing the spinal cord or nerve roots.

2. How to Perform

Warning: Use caution with patients who have a history of cardiovascular issues, fainting, or cerebrovascular disease.

1. The patient is seated comfortably.
2. The examiner instructs the patient to take a deep breath and hold it.
3. The patient is then asked to "bear down" as if having a bowel movement (straining).
4. Alternatively, the patient can be asked to blow forcefully into a closed fist or against the back of their hand without letting air escape.

3. Positive & Negative Sign

Positive Sign (Test is POSITIVE):
A positive test is the reproduction or increase of pain in the back or radiating pain into the limbs (radiculopathy). This indicates that the increased venous pressure is further compressing an already irritated nerve root.

Negative Sign (Test is NEGATIVE):
A negative test is when there is no increase in spinal or limb pain. (A feeling of pressure in the head or ears, or flushing of the face, is a normal physiological response).