Comprehensive Osteopathic Medical Licensing Examination (COMLEX USA) Practice

In bilateral sacral flexion, what happens to the spring test results?

1. Remains constant

2. Inverts the response

3. Becomes negative

4. Can vary depending on position

The correct answer is: Becomes negative

In the context of bilateral sacral flexion, understanding the spring test results is essential for identifying the functional mechanics of the sacrum. Bilateral sacral flexion occurs when the sacrum moves forward (a motion that is flexion), which can lead to specific responses during manual examination. The spring test assesses the mobility of the sacrum by applying a springing force to the sacral area while the patient is prone. Under normal conditions, the sacral motion should allow the examiner to feel resistance against the springing motion if the sacrum is in a neutral position. However, in cases of bilateral sacral flexion, the normal range of sacral motion is altered. When performing this test in the presence of bilateral sacral flexion, the sacral base is typically found to be anteriorly positioned, leading to decreased resistance to the springing motion. This results in a negative spring test, indicating that there is less resistance than expected, which is characteristic of the altered biomechanics present during bilateral sacral flexion. This understanding clarifies why a negative spring test result occurs specifically in this pattern of sacral motion, distinguishing it clearly within the broader context of sacral mechanics as it relates to somatic dysfunction.