L7 - Gross Anatomy of the Head and Neck Flashcards
What comprises the superficial structures of the head?
1) Skin + Glands
2) Muscles of Facial Expression
What are the 3 types of glands that are associated with the superficial structures of the head?
Salivary
Sweat
Lacrimal
What do the muscles of facial expression do?
Move the lips, nostrils, eyelids and ears
Which cranial nerve provides the motor supply to the muscles of facial expression?
Cranial Nerve VII (Facial Nerve)
Which cranial nerve provides the sensory supply to the superficial structures of the head?
Cranial Nerve V (Trigeminal)
What is a pro and con of the head being very vascularized?
Con - Lots of bleeding can occur with injury
Pro - Rapid healing due to good blood supply
What is fascia?
Loose connective tissue
Why is there extensive venous drainage systems present in the head and neck?
The head/face is highly vascularized so there needs to be an extensive venous drainage to return the blood back to the heart.
What is the name of the vein that drains the tongue?
Lingual Vein
What is the name of the vein in the neck that is formed by the connection of two vessels and drains the blood from the entire head?
External Jugular Vein
Why is the facial nerve easily damaged?
Lies very close to the skin
What is the name of the large jaw closing muscle?
Masseter
Which two vessels in the head form the jugular vein?
1) Maxillary Vein
2) Linguofacial Vein
Which two salivary glands are seen on the lateral aspect of the face?
Mandibular Salivary Gland
Parotid Salivary Gland
What are the superficial structures of the lateral aspect of the face (List).
Muscles of Facial Expression Parotid and Mandibular Salivary Glands Mandibular Lymph Nodes External Jugular Vein + its branches Masseter Muscle Facial Nerve (VII) Trigeminal Nerve (V) - some branches
What is the difference in the salivary glands of herbivores vs. carnivores?
Herbivores have larger salivary glands and more salivary production - aids in digestion of fibrous food (hay)
Carnivores have smaller and compact salivary glands.
What is unique about the appearance of the parotid and mandibular glands in a horse compared to a dog?
They are hard to distinguish in a horse (appear as one large gland).
Which salivary gland is located closer to the ear?
Parotid gland
Which structures of the immune system are palpable during examination and are present in the head?
Mandibular lymph nodes
Where does the mandibular salivary gland lie?
Lies between the maxillary and linguofacial veins.
Which vessels in the head/neck are considered surgical landmarks?
Maxillary and linguofacial veins
What are the three principal branches of the trigeminal nerve?
1) Opthalmic
2) Maxillary
3) Mandibular
Which branches of the trigeminal nerve are exclusively sensory?
1) Opthalmic
2) Maxillary
Which branch of the trigeminal nerve is both sensory and motor?
Mandibular
Which muscles are considered the jaw closing muscles?
Masseter
Temporalis
Digastricus
Pterygoid
Which branch of the trigeminal nerve supplies the jaw closing muscles?
Motor component of the mandibular branch
From where does the mandibular branch of the trigeminal nerve enter the mandible?
Medial side of the Ramus
Runs within the bone
T/F - The branches of the trigeminal nerve (V) will be seen easily upon initial dissection of the head?
False - located deep in the position and are hidden away behind the jaw closing muscles
What are the branches of the facial nerve (VII)?
1) Auriculopalpebral
2) Dorsal Buccal
3) Ventral Buccal
Which branches of the facial nerve supply motor fibres to the facial muscles?
Dorsal Buccal
Ventral Buccal
What is the stylomastoid foramen?
Small opening in skull where the Facial nerve exits
Which cranial nerve curves around the ear canal?
Facial Nerve (VII)
What does the lacrimal gland do?
Produces tears
Fibres from which branch of the ANS innervate the salivary glands?
Parasympathetic fibres
What is the name of the first cervical vertebra?
Atlas
What is the name of the second cervical vertebra?
Axis
What makes the atlas unique?
Long wings projecting laterally
What makes the axis unique?
Extended spinous process
What is the standard number of cervical vertebrae in domestic mammals?
7
What is the name of the joint at which the atlas articulates with the skull?
Atlanto-occipital joint
What is the significance of the atlanto-occipital joint in small animals?
Area where CSF can be collected for diagnostics.
What type of movement does the atlanto-occipital joint allow?
Up-down movement of the head (nodding)
Which joint allows the side-to-side movement of the head?
Atlanto-axial joint (between the atlas and axis)
Why is it difficult to feel the spinous processes of the vertebrae in the neck in most animals?
The neck contains epaxial muscles that are well developed.
- lie dorsal to the transverse processes of vertebrae
What is the function of the nuchal ligament?
Support structure that minimizes the energy required to lift head from the ground
- reduces muscle contraction
Which species lack a nuchal ligament?
Pigs
Cats
What is the nuchal ligament composed of?
connective tissue fibres
In dogs, where does the nuchal ligament run?
From the axis to the thoracic vertebrae.
In horses, where does the nuchal ligament run?
From the skull to the withers region (dorsal)
What is present between the vertebral spines and nuchal ligament in a horse?
Synovial bursa
