A 6-year-old boy who had been treated with bilateral medial rectus muscle recessions 3 years earlier for congenital esotropia was undergoing bilateral inferior oblique muscle recessions to correct inferior oblique muscle overaction. The right inferior rectus muscle was inadvertently cut during this surgery and was irretrievable. To manage this complication, the medial rectus. Medial muscular branch: supplies inferior rectus, medial rectus, and inferior oblique muscles. Lacrimal artery: partially supplies lateral rectus muscle. There is some partial supply of the inferior oblique and inferior rectus muscles from the infraorbital artery, a branch of the maxillary artery (from the external carotid artery circulation). The superior rectus and inferior oblique muscles working together pull the eye upward without rotating the eye. To depress the eye while looking straight ahead, the inferior rectus and superior oblique contract together as the superior rectus and inferior oblique relax.

The Actions and Innervation of Extraocular Muscles. Elevation is due to the action of the superior rectus and inferior oblique muscles, while depression is due to the action of the inferior rectus and superior oblique muscles. When the eye is abducted, the rectus muscles are the prime vertical movers. To investigate refractive changes after strabismus correction by combined recession of the Medial Rectus (MR) and Inferior Oblique (IO) muscles. We reviewed cases of combined MR and IO recession. Individuals with both preoperative refraction measurement and one month postoperative measurements were included.

Medial Rectus Function

Option A is the only option where both muscles are part of the orbital floor.Also, the last sentence in the question stem is a total modifyer of what one would expect the question to be asking. It is not asking for you to assume that these muscles have been severed, paralyzed, or rendered flacid. It is asking you to assume that they have become 'entrapped' if the muscle is entrapped, then it cannot allow the eye to move into whatever position it would be in when the muscle is at its lengthened position. So in this case, It is the inferior rectus being entrapped in a functionally shortened position that is preventing upward gaze.

Medial Rectus And Inferior Oblique Dmg Muscles

its bc this are the only 2 muscles on the orbital floor google orbital floor muscles in google imageshttps://www.google.com/search?q=orbital+muscles&tbm=isch#imgrc=NNOONaLRFuEP1M:

Orbital floor fracture:

1- Infraorbital nerve injury: Numbness and paresthesia of the upper cheek, upper lip, upper gingiva.

2- Entrapment of the inferior rectus muscle: Impaired upward gaze

3- Enophtalmosis

4- Clousing of maxillary sinus: Teardrop sign

Inferior oblique = helps you look up & in.

Also, they said floor of the orbit, so it makes sense that the inferior muscles would damaged.

The obliques do the opposite action of their name. Inferior oblique moves the eye UP and OUT (extortion, elevation, ABduction). Since the question says that there is a fracture involving the orbital floor, that automatically rules out D (medial rectus and inferior oblique), leaving the only logical answer to be the inferior rectus and inferior oblique. https://www.youtube.com/watch?v=lWKkHWWDIEI

The medial rectus is a muscle located in the eye socket. This muscle works within a sort of pulley-system and, along with other extraocular muscles, helps to control certain movements of the eye. The role of the medial rectus in eye movement is that of adduction. That is to say, the eye moves in an inward direction, as toward the nose. Several medical conditions have the potential to compromise the function of this important muscle of the eye.

The nerve supply to the medial rectus muscle is provided by the oculomotor nerve, also referred to as the third cranial nerve. While working to control the majority of the movements of the eye itself, this nerve provides other functions as well. The oculomotor nerve is also responsible for holding the eyelid in an open position in addition to constricting the pupil.

Medial rectus palsy is a medical condition known to have an adverse effect on the medial rectus muscle. This condition occurs frequently when there has been a traumatic brain injury. The damage to the oculomotor nerve causes nerve and sometimes muscle paralysis. Improper eye movement and double vision are typical symptoms of this condition. Medications are sometimes helpful in alleviating troubling symptoms, although surgical intervention is sometimes necessary.

Esotropia is another condition affecting the medial rectus muscle. In this condition, the patient exhibits what is commonly referred to as a squint. What this means is that the eye, or sometimes both eyes, turn in an inward position. This is commonly known as being cross-eyed. A surgical procedure called medial rectus recession is often employed in an attempt to correct this condition.

Medial wall fractures sometimes occur when there has been some sort of facial trauma. This type of fracture is another common cause of damage to the medial rectus muscle. The orbital floor is normally affected along with the medial wall itself. Swelling and skin discoloration are often the only outward signs that this type of fracture has occurred. While symptoms sometimes resolve on their own, surgery is very often required.

An abnormal muscle thickness involving the medial rectus is sometimes found in a patient with Grave's Disease, although it can be present with no sign of disease. This condition causes pain as well as impaired vision. The use of medications such as eye drops along with the use of a humidifier is often enough to relieve troublesome symptoms in those with mild cases of this condition. Radiation or surgery are only necessary modes of treatment in rare cases which do not respond to more conservative treatments.