A positive forced duction test most strongly indicates which type of issue?

• A. Neurogenic
• B. EOM restriction
• C. Myasthenia gravis
• D. Normal

Answer: (B)

A positive forced duction test signals a mechanical restriction of the extraocular muscles. When the eye is moved passively in the direction of trouble, there is resistance that you can’t overcome, indicating something physical is blocking movement—such as scar tissue, fibrosis, entrapment, or a restrictive pulley. This points away from nerve or muscle weakness as the primary issue.

In neurogenic problems like a nerve palsy or conditions like myasthenia gravis, passive movement is not blocked by a physical constraint—the issue is with innervation or neuromuscular transmission—so the forced duction test tends to be negative. A normal, unrestricted globe movement aligns with a lack of mechanical restriction.

So, the strongest implication of a positive forced duction test is an EOM restriction due to mechanical factors.