MRCP UK EXAMINATIONS

Detailed explanation-1: -Contraction of the medial rectus pulls the eye towards the nose (adduction or medial movement). Contraction of the lateral rectus pulls the eye away from the nose (abduction or lateral movement).

Detailed explanation-2: -When the eye is abducted, the rectus muscles are the prime vertical movers. Elevation is due to the action of the superior rectus, and depression is due to the action of the inferior rectus. When the eye is adducted, the oblique muscles are the prime vertical movers.

Detailed explanation-3: -The lateral rectus moves the eye horizontally laterally (abduction). The medial rectus muscle moves the eye horizontally medially (adduction). The superior oblique muscle incyclotorts the eye, and the inferior oblique muscle excyclotorts the eye.

Detailed explanation-4: -Superior Oblique (SO) Rotates the top of the eye towards the nose (intorsion) Moves the eye downwards (depression) Moves the eye outwards (abduction)

Detailed explanation-5: -When the eye is ADducted, the axis of the globe is better in line with the axis/force vector of the superior oblique. This allows the superior oblique to pull straight forward and depress the eye. Therefore, ADducting the eye isolates the depressing action of the superior oblique.