Lateralis rectus muscle (Lrm)
The lateralis rectus muscle is a rectangular sheet muscle composed of
oblique muscle fibers. It originates from fleshy, narrow fibers of the
parabasisphenoid bone and extends to insert into the scleral cartilage.
The origin site of the lateralis rectus muscle is ventral to the optic
nerve and posteroventral to the origin site of the ventral rectus
muscle. Its insertion site is dorsal to the insertion site of the
bursalis muscle on the scleral cartilage\RL.
Origin: Fleshly, from the parabasisphenoid bone\RL.
Insertion: Aponeurotic, on the scleral cartilage\RL.
Function: Pulls the eyeball towards the posterior temporal pole
(abduction).