At thoracic level, what position do the trunk and lower extremities tend to assume due to hypotonia and flaccidity?

• A. Frog leg position
• B. Fully extended legs
• C. Crossed legs while seated
• D. Sitting with knees extended and feet together

Answer: (A)

When there is loss of muscle tone (hypotonia) and flaccidity in the trunk and legs, gravity becomes the main force shaping posture because the muscles can’t actively hold joints in alignment. With the hip and knee muscles not resisting gravity, the limbs settle into a relaxed position that requires minimal effort to maintain. This commonly manifests as the hips being flexed, abducted, and externally rotated, with the knees flexed, which is the frog-leg posture. The trunk also tends to slump forward rather than stay upright because trunk extensor and postural muscles aren’t providing support.

This pattern contrasts with positions that require active muscle tone to hold the joints in extension or midline alignment, such as legs that are fully extended, crossed legs while seated, or knees extended with feet together. In the setting of thoracic-level hypotonia, those more extended or midline positions are less likely to be maintained without active tone, making the frog-leg posture the more typical resting position.