CHAPTER 4. THE MUSCULAR SYSTEM
TEMPORAUS (closes jaw)
MASSETER (closes jaw)
MEDIAL PTERYGOID (closes jaw) LATERAL PTERYGOID (opens jaw)
Figure 4-59 Fig. 4-60. Muscles of the eye. S.O., superior oblique; 1.0., inferior oblique, S.R., superior rectus; LR., inferior rectus; M.R., medial rectus; L.R.. lateral rectus. Each extrinsic muscle of the eye attaches to the eye as well as to the nasal aspect of the orbit. None of the eye muscles attach to the temporal wall of the orbit. All the muscles, including the levator palpebrae muscle, originate in the tendinous ring on the bone that surrounds the optic foramen, with the exception of the inferior oblique. which originates at the nasal aspect of the maxillary bone (fig. 2-29).
The mnemonic for innervation of the eye muscles is "LR6, S04" (Lateral Rectus - cranial nerve 6, Superior Oblique - cranial nerve 4). The other muscles, including the levator palpebrae superioris, are innervated by cranial nerve 3.
Figure 4-60