Term
| 1. What is a check ligament? Why is it so named and how does it function? Give examples. What are the main indications for check ligament desmotomy? |
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Definition
-Check ligaments provide passive support without expenditure of muscular effort (checking= preventing dropping of the fetlock)
-Proximal check ligament is the radial head of SDF m.; attaches to the middle phalanx and prevents buckling forward of the digit by pulling back on the middle phalanx
-Distal check ligament is an extension of palmar carpal ligament; inserts on distal phalanx and counteracts its extension
-Indications for desmotomy of the distal check ligament include contracted tendons or laminitis |
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Term
| 2. For each forelimb structure on the left below give a hind limb analog. long head of triceps m. ________________________ brachiocephalicus m. ________________________ cephalic vv. ________________________ |
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Definition
| -Long head of triceps m. = Rectus femoris of the quadriceps femoris -Brachiocephalicus m. = Middle gluteal m. -Cephalic v. = Medial saphenous v. |
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Term
| 3. Compare the carpal and tarsal canals with regard to structure and contents. |
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Definition
-Carpal canal formed via the flexor retinaculum, the medial collateral ligament, to the palmar aspect of the accessory carpal bone; contains the following structures: -Digital flexor tendons, palmar nerves and major vessels of the region
-Tarsal canal formed by a groove on the medial side of the calcaneus and the flexor retinaculum; contains the following structures: lateral tendon of the deep digital flexor muscle and the plantar nerves and major vessels |
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Term
| 4. Compare the superficial digital flexor muscles of fore and hind limbs, actions and check ligaments. |
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Definition
-Fore limb:
-SDF arises from medial epicondyle of the humerus and inserts on the proximal end of the middle phalanx and the distal end of the proximal phalanx
-SDF extends the carpus and digits
-Proximal check ligament is the radial head of the superficial digital flexor m and attaches to the middle phalanx to prevent buckling forward of the digit
-Hind limb:
-SDF attaches to femur deep to gastroc, attaches superficially to calcanean tuberosity, extends to plantar aspect of the limb to the middle phalange
-SDF is responsible for flexing the stifle and digits & extending the tarsus
-no check ligaments are associated with SDF on hind limb |
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Term
| 5. Differentiate between the interosseous tendon and ligament and give the clinical name for the former. |
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Definition
-The interosseus ligament is between the olecranon and radius
-The interosseus tendon is homologous to the interosseus muscle in dogs except it is mostly tendonous and plays a role in the stay apparatus and locomotion
-Inerossius tendon = Suspensory Ligament |
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Term
| 6. Compare and contrast the lateral digital extensor tendons of fore and hind limbs. |
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Definition
| - In the forelimb, the lateral digital extensor muscle extends to proximal or middle phalanges. The LDET in the hindlimb completely joins the long digital extensor m. tenden. |
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Term
| 7. Compare and contrast the main digital extensor tendons of fore and hind limbs. |
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Definition
| -In the forelimb, the common digistal extensor tendon extends to distal phalanges. In the hind limb, it is the long digital extensor that fulfills this role. |
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Term
| 8. What is the name and location of the major artery of the fore and hind cannon regions ? |
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Definition
| - Medial Palmar A. in forelimb and Dorsal Pedal a. in hind limb. |
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Term
| 9. What is the lever type bone that projects out behind the carpus? What is it in the tarsus ? |
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Definition
| - Accessory carpal bone in the carpus and Tuber calcis bone in the tarsus |
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Term
| 10. What are the attachments of the interosseous tendon? Which can be palpated on the long pastern bone? (see also digit notes) |
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Definition
| -Cannon bone & lateral sides of proximal sesamoid bones. The extensor branch of the suspensory ligament is palpable. |
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Term
| 11. What does the palmar carpal ligament give rise to? |
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Definition
| - Dorsal wall of the carpal canal continues on to become distal check ligaments |
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Term
| 12. What are the 3 carpal joints and how much movement is in each? |
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Definition
-Radiocarpal – considerable movement, more movement than intercarpal
-Intercarpal – considerable movement
-Carpometacarpal – virtually no movement |
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Term
| 13. Differentiate between the suspensory apparatus and the suspensory ligament. Compare the check ligaments of fore and hind limb. |
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Definition
- Suspensory apparatus – suspensory ligament plus the distal sesamoidean ligaments, the three tendons form a passive support system for the fetlock
-Suspensory ligament – just the one ligament
-See question 4 for comparison of check ligaments – check ligaments poorly developed in the hind limb |
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Term
| 14. What is the "break joint" and what is the significance of it in sheep production? |
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Definition
-Break joint – distal cannon bone physis
If the physis is broken at the slaughter house the animal is considered to be a lamb |
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Term
| 15. There is considerable difference between fore and hind stay mechanisms. What parts are similar? |
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Definition
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Term
1. Give a synonym(s) for each of the following terms:
proximal phalanx = ____________________________ = ______
middle phalanx = ____________________________ = ______
distal phalanx = ____________________________ = ______
distal sesamoid bone = ____________________________ |
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Definition
Proximal phalanx= Long Pastern Bone = P1
Middle phalanx= Short Pastern Bone = P2
Distal phalanx= Coffin Bone = P3
Distal sesamoid bone= Navicular bone |
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Term
palmar or plantar = ___________________
interosseous tendon = ___________________
superficial distal sesamoidean ligament = __________________________
middle distal sesamoidean ligament = _____________________________ |
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Definition
Palmar or plantar= Volar
Interosseus tendon= Suspensory Ligament
Superficial distal sesamoidean ligament= Straight sesamoidean ligament
Middle distal sesamoidean ligament= Oblique sesamoidean ligament |
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Term
| 2. What is the de facto proximal sesamoidean ligament ? |
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Definition
| - The interosseous tendon is actually the proximal sesamoidean ligament. |
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Term
| 3. Which distal sesamoidean ligament spans over 2 joints? |
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Definition
| -Straight sesamoidean ligament |
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Term
| 4. Why are the (proximal) sesamoid bones prone to fracture? |
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Definition
| - The proximal sesamoid bones are prone to fracture due to the stress places on the ligamentous system when body weight places downward force on the fetlock joint in rapid motion - sesamoids caught between suspensory ligament and distal sesamoidean ligaments. |
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Term
| 5. What is the meaning of plantigrade, digitigrade, unguligrade? Give examples of each. |
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Definition
- Plantigrade= All of the foot (the entire Sole) is on the ground – humans, bears
-Digitigrade=stands on digital pads – camelids and carnivores
-Unguligrade= stands on hoof – horses, cows, most ungulates |
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Term
| 6. What are the 3 parts of the wall; what are the bars? |
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Definition
| -The three parts of the wall are the toe, quarters, and heel. The bar is where the wall is reflected inward and back towards the toe (at the heel). |
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Term
| 7. What is the white line and how is it significant? |
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Definition
| -The white line is the junction of the wall and sole. The white line is the spot where farriers place nails when shoeing. |
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Term
| 8. What is the: frog, heel, bulbs, and coronet? |
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Definition
-Frog = wedge-shaped, horny prominence in the sole of a horse's hoof: the space between the bars
-Heel =caudal part of the hoof
-Bulbs =caudal aspect of the heel
-Coronet =junction between skin and hoof |
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Term
| 9. A hoof pick is used to clean manure and dirt out of the “bottom” of a horse’s foot. What deep groove(s) would the hoof pick be especially useful for? |
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Definition
| - The collateral sulci (paracuneal grooves) are deep grooves separating the bars from the frog that the hoof pick is especially useful for. |
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Term
| 10. What produces the hoof wall and how does outgrowth of the wall effect its flexibility? |
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Definition
| -The long conical papillae in the coronary band produce tubular horn which forms the bulk of the hoof wall. The toe grows out slowly because it's the long part of the wall and therefore is the oldest part of the hoof wall, as the hoof wall horn ages it becomes less moist and therefore less flexible. |
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Term
| 11. What is the structure and function of the equine collateral cartilages of the coffin bone? |
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Definition
| -The collateral cartilages are attached to the wings of the coffin bone and not to the hoof. When the foot strikes the ground the digital cushion expands and pushed the collateral cartilages out so that the veins are compressed forcing blood to move up the leg. |
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Term
| 12. Why is the navicular bone so named? What are the principal attachments of it? What is on the dorsal and palmar surface of it? |
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Definition
| - The navicular bone is shaped like a boat, hence the name. It is attached to the long pastern by suspensory ligaments of navicular bone and distal sesamoidean ligament bands navicular to the coffin bone. The dorsal surface is in contact with the palmar surface of the coffin joint. The palmar surface is in contact with the navicular bursa. |
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Term
| 13. What is the main structure putting pressure on the navicular bursa? |
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Definition
| - Deep flexor tendon can put pressure on navicular bursa and may cause pain. A long toe will drop heel causing more pain due to tendons being pulled tight because of increased extension. An enlarged heel will reduce pain due to increased flexion. |
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Term
| 14. What is the structure and significance of the digital cushion ? |
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Definition
| - The digital cushion is similar to the digital pad of the dog, made of collagen, adipose tissue, and pieces of hyline cartilage. It becomes squashed when weight is put on the foot and compresses the vein between the hoof wall and the cartilages and squeezes blood out of the venous spaces that lie between the skin and cartilages. |
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Term
| 15. Compare and contrast the bovine foot with that of the horse. |
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Definition
- Cows are different from horses because:
They bear weight on the heel and the wall. The bovine heel is separate from the wall. In the horse the heel is a part of the wall (the volar third). The heel of cattle is homologous to the bulbs of the equine heel.
Bovine feet have a wall and sole but no homologue of the frog or collateral cartilages.
The laminae lack secondary (microscopic) laminae. This probably relates to the fact that in the horse the wall bears all the weight but in cattle less than half of the weight is borne by the wall. Therefore laminitis in cattle is not as painful as in the horse. |
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Term
| 1. What is sexual dimorphism? Give examples with regard to teeth, horns, and antlers. |
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Definition
-Sexual dimorphism is where only one member of the sex will exhibit a structure or physical characteristic
-Anters – deer, moose, & elk males only have antlers
-Horns – occurs in both sexes except for in Dorset sheep
-Teeth – horse canines in mares are often small and may not erupt |
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Term
| 2. What is the basic mammalian dental formula and which animals have it? |
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Definition
-Basic formula is:
2 (I 3/3, C 1/1, P 4/4, M 3/3) = 44 (full adult mouth)
2 (Di 3/3, Dc 1/1, Dp 3/3) = 28 (full deciduous mouth)
-Pig is the only mammal that has the full set |
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Term
| 3. Compare camelid dentition with ruminant dentition. What are the fighting teeth and “ivory”? |
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Definition
-Llama and ruminants both have dental pads but llamas have upper canines and I3 in addition to dental pad
-Llamas lower canines are differentiated from incisors; ruminants the canine is I4
-Fighting teeth are llamas upper canines and I3; often cut off
Ivory???? |
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Term
| 4. What are the tusks of swine and elephants and how are these teeth similar to rodent incisors and elephant tusks? Relate this to the pulp cavity. |
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Definition
-Tusks of swine are the canines
-Tusks of elephants are upper I2’s
-Similar to rodent incisors in that have continuous growth and eruption and also have wide open root which facilitates growth (increase in length) throughout life
Pulp?????? |
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Term
| 5. Differentiate between the cup and infundibulum, enamel spot and dental star, clinical crown and reserve crown. Which teeth have infundibula and how many in horse and ox? What is apparent reason for the formation of infundibula? |
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Definition
-Cup is the depression in the infundibulum and is often filled with black decaying material
-Enamal spot is the bottom of the cup and the dental star is a darker, secondary dentin filling the pulp cavity that is rostral to the enamel spot
-Incisor teeth have infundibula
-Formation of infundibula occurs as a mechanism to combat the wear and tear of grinding; enamel is harder than dentine and becomes sharper as it wears down aiding in the cutting and macerating of the plants |
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Term
| 6. What forms the ruminant corner teeth? What is the dental pad? Which animals have it? |
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Definition
| -Not sure if this is a typo but thought corner teeth were in equines and if so then that is the I3. For ruminants would guess that the I3 & I4 are the corner teeth. -A dental pad is a heavily cornified epithelium used, in conjunction with the lower incisors, to grind food; replaces the upper incisors and canines in ruminants. |
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Term
| 7. What is the wolf tooth? Why are they removed? Why are they not cheek teeth? |
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Definition
-horse’s rudimentary upper first premolars and are usually absent
-removed so they don't interfere with the bit and because owners think they need to be removed (think cox's crazy story about how the name "wolf tooth" came about)
-not cheek teeth because they dont sit in the cheek area like the other pre-molars and molars |
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Term
| 8. What distinguishes molars and premolars in general? What is the exception? |
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Definition
-Molars and premolars are differentiated by premolars having deciduous precursors (except for PM1)
-The exception is horses where the molars and premolars are indistinguishable except for eruption patterns. |
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Term
| 9. Define caps, alveolus, deciduous teeth. At what age will a horse obtain a full in wear deciduous mouth and a full in wear permanent mouth? (a full mouth refers only to the lower incisors) |
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Definition
-Caps = A deciduous tooth remaining attached to its permanent replacement; affected teeth are Dp2, Dp3, Dp4 -Alveolus = the bony sockets of the incisive, mandible, and maxillary bones in which the roots of teeth are embedded -Deciduous teeth = “baby teeth” that develop early in life to give the young animal a functional set of teeth; smaller and fewer in number than permanent dentition
Age for full in wear deciduous teeth: 9 months
Age for full in wear permanent teeth: 5 years |
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Term
| 10. Be able to assign a Triadan number to any equine tooth. What two teeth numbers are most often not present in either gender? Which numbers are not present as deciduous teeth? Which numbers are not present in most mares? Which two numbers are most likely to cause problems with bits? |
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Definition
-Lower PM1 and Upper PM1 are rare.
-Mares lack canines
-premolars |
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Term
| 11. What are the 2 major factors used in dental age estimation? |
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Definition
-Eruption dates (most reliable)
-Wear - are first “in wear” and when entire occlusal surface is worn down then the tooth is level |
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Term
| 12. Why are hypsodont teeth protected from abscess? What occurs instead? |
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Definition
-Hypsodont teeth are protected because enamel protects the unerupted portion of the tooth from bacterial penetration
-Alveolar periostitis (inflammation of the alveolar periostium) occurs instead |
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Term
| 13. Differentiate horns from antlers. What are cervids? |
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Definition
Horns Antlers
Hollow Solid
Don't shed Shed Annually
Polled No Polling
Not branched Branched
cervids: deer, elk, antelope, reindeer, moose |
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Term
| 14. What is meant by the term polled? What are some polled breeds? Why is polled a problem for goats? How could a breeder breed for polled kids without getting defects? |
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Definition
-Polled is a term for horns that do not develop
-Polled breeds are Polled Hereford, Red Polled Ostland, Swedish Red Polled (cattle), Chengde Polled (goat), Polled Dorset (sheep)
-In goats polled is associated with hermaphroditism |
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Term
| 1. What are the boundaries of the nasal cavity? |
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Definition
| -Boundaries are external nares to the choanae |
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Term
| 2. What are the choanae and what is their clinical significance? |
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Definition
| - Choanae are the passageways between the nasal cavity and the nasal pharynx. Clinical significance is choanal atresia. |
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Term
| 3. What is the false nostril and what is its significance? |
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Definition
| - The false nostril is the nasal diverticulum, a cutaneous pouch lateral to the nasal cavity. It allows extreme dialation of the nostril (flaring). |
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Term
| 4. How do the paranasal sinuses form and what are their probable functions? |
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Definition
| - The paranasal sinuses form by invasion of nasal epithelium between the external and internal plates of the skull. Their function may be to give a large head with light weight, protection, or to create resonance for vocalization. |
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Term
| 5. Which species have a palatine sinus and what does it communicate with? What serves as a partial barrier between these two cavities? |
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Definition
-Only in ruminants, communicates with the maxillary sinus
-The infraorbital canal separates these two cavities |
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Term
| 6. What is the lacrimal bulla and what is its significance? |
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Definition
| - The lacrimal bulla if found in ruminants at the caudal end of the maxillary sinus. It is paper thin sheet that acts as a barrier at the end of the maxillary sinus. |
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Term
| 7. What is the prominent external landmark of the equine maxillary sinus? |
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Definition
| - The facial crest (unique to the horse) forms a prominent external landmark for the equine maxillary sinus. |
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Term
| 8. Compare and contrast the rostral and caudal maxillary sinuses and their communications |
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Definition
- The horse is unique in the fact that the maxillary sinus is divided into caudal and rostral compartments. Pigs and ruminants only have one maxillary sinus.
-The caudal compartment communicates with the frontal sinus via frontal-maxillary opening (unique to the horse).
-The rostral compartment is separated from the caudal compartment by a perpendicular plate (bony septum). It opens into the nasal cavity via a nasomaxillary opening. |
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Term
| 9. In which two species does the frontal sinus cover the entire brain case? |
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Definition
| - The frontal sinus of the ox and the pig covers the entire brain case. |
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Term
| 10. What is the significance of the equine frontal sinus in removal of the last molar tooth? What is frontal maxillary opening and which species have it. |
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Definition
| - In the horse, the frontal sinus is the site of a trephine hole (rostral-medial to orbit) where a punch is passed through to reach the last molar tooth.Only the horse has one. |
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Term
| 11. How is the chonchofrontal sinus formed and how is it drained? |
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Definition
| - The chonchofrontal sinus is formed by an extension of the frontal sinus into the dorsal concha. The frontal sinus is drained by drilling a hole through the dorsal concha with a intramedullary bone pin. |
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Term
| 1. What are the boundaries of the pharynx? |
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Definition
-The boundaries of the pharynx are (pretty good pictures on TVA 117, 118):
a. Nasopharynx: rostrally by soft palate and hard palate, dorsally by nasal septum, caudally by roof of the nasopharynx, ventrally by palatopharyngeal arch
b. Oropharynx: dorsally by soft palate, ventrally by tongue (it ends caudally at the end of the soft palate/start of the epiglottis)
c. Laryngopharynx: dorsally by epiglottis, caudally by the trachea
d. Overall pharynx: dorsally by nasal septum, rostrally by hard palate, caudally by trachea and roof of nasaopharynx, ventrally by tongue |
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Term
| 2. What is/are the alar cartilages, vomer, ostium, orifice, meatus, pharynx, and auditory tube? |
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Definition
-Alar cartilage: cartilage that supports the nasal rim of the nostril (important because horses are obligate nose breathers and the cartilage and muscles can flare them wide)
-Vomer: a gutter-shaped bone supporting the floors of the cartilaginous nasal septum; it is caudal ventral in the septum
-Ostium: mouth or orifice, opening into a tubular organ, area between 2 distinct body cavities (so in this case, I think he is referring to the intrapharyngeal ostium which, in the horse, seals the opening to the nasopharynx from the larynx)
-Orifice: the entrance or outlet if any body cavity; any foramen, meatus, or opening (in the notes, Dr. Cox refers to the auditory tube orifice which opens into the nasapharynx)
-Meatus: an opening or passage; there are 4 nasal passageways (there is a good picture in TVA 486):
i. Ventral meatus: largest, ventral to ventral concha (where a stomach tube is passed)
ii. Middle meatus: between dorsal and ventral conchae
iii. Dorsal meatus: dorsal to dorsal concha
iv. Common nasal meatus: lateral to nasal septum (unites the other meati)
-Pharynx: crossroads of the digestive and respiratory tracts (a.k.a. the throat)
-Auditory tube: narrow channel connecting the nasopharynx to the middle ear |
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Term
| 3. What is an obligate nasal breather? What species have this trait? |
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Definition
| -An obligate nasal breather is an animal that can only breath through the nostrils and not through the mouth (i.e. horses) |
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Term
| 4. How do tonsils differ from lymph nodes? Describe the unique anatomy of the bovine palatine tonsil (TVA p.118). |
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Definition
| - Tonsils are lymphoepithelial structures made up of aggregations of unencapsulated lymph nodules within various mucosa. Lymph nodes are made up of lymphoid tissue as well, but consist of an outer cortical and an inner medullary part. They are the main source of lymphocytes for the blood. The bovine palatine tonsil has a unique structure. It is sort of like a leaf with the leaf veins opening up into the oropharynx (that’s the best description I can come up with…see TVA 118 for a picture which might make it more clear). This means that it is buried deep and only an orifice is visible from the oropharynx. |
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Term
| 5. What is the piriform recess and what is the functional significance of it? |
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Definition
| - The piriform recess is a pair of gutters that run beside the rostral projection of the larynx, below the epiglottis, and into the pharynx. They are lateral to the larynx and form the ventral part of the laryngeal pharynx. It is helpful to the ox because it lets saliva “dribble” down the esophagus without swallowing allowing mass amounts of saliva to buffer the rumen. |
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Term
| 6. What is the topography of the equine auditory tube diverticula? What is their clinical significance? What vessels, nerves and lymph nodes lie adjacent to them? |
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Definition
| - The equine auditory tube diverticula = the guttural pouches. To see the topography, it would probably be most clear to look at TVA 500, but I will give my little description here. It is divided into right and left guttural pounches by a septum. Each side is then divided into medial and lateral compartments by the stylohyoid bone (comes up from ventrally and reaches about half way up the guttural pouch). The medial retropharyngeal lymph nodes bulge into the guttural pouch ventrally to the pouch and medially to the stylohyoid. The longus capitis ventralis bulges into the pouch dorsally along the midline (it connects to the dorsal end of the septum and it kind of looks like the septum comes from the rectus capitis ventralis, but I’m not sure about that). Basically it is ventral to the brain, dorsal to the esophagus and larynx, and medial to the mandible. There are a lot of vulnerable structures lateral to the pouches. These make the pouches clinically significant. They are the internal carotid artery (caudal and then dorsal surface, can hemorrhage into the pouch if eaten away by aspergillus which is a bacterial family), the external carotid artery (lateral surface), retropharyngeal lymph nodes (lateral surface), and cranial nerves IX, X, XI, and XII. |
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Term
| 7. What muscles pull the hyoid apparatus rostral and caudal? How could you pull the larynx forward to aid intubation? |
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Definition
| - The hyoid apparatus is pulled caudally and ventrally by the sternohyoideus and thyroideus and rostrally by the geniohyoideus. Pulling the tongue will make the larynx move forward to help with intubation. |
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Term
| 8. Which component of the hyoid apparatus is the largest and which bears a lingual process in the horse ? Where is the hyoid apparatus attached to the skull? |
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Definition
-stylohyoid bone is the largest
-basihyoid bone(the lingual process is where the base of the tongue attaches)
-at the base of the skull by the cartilage of the auditory tube (tympanohyoid cartilage) |
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Term
| 9. What is the only hyoid bone to cross the midline? |
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Definition
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Term
| 10. What are 4 functions of the glottis in domestic mammals? |
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Definition
-It acts as a valve to close off the respiratory pathway in order to:
1. Prevent entry of good or other debris into the trachea
2. Create a negative pressure in the thorax by inspiration against a closed glottis. This then allows aspiration of ingesta into the thoracic esophagus for regurgitation
3. Trap air in the chest during the abdominal press in defecation and parturition. The air trapped in the lungs serves to stabilize the diaphragm for the abdominal press.
4. Dislodge foreign matter from the vestibule by coughing and causing a forced expiration against a closed glottis which opens up slightly to release a “blast” of air to dislodge debris. |
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Term
| 11. Differentiate between the glottic cleft and the glottis. |
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Definition
-glottic cleft = the narrow passageway through the glottis
-glottis = vocal folds + arytenoid cartilages and covering mucosa |
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Term
| 12. What is the shape, composition and position of the laryngeal cartilages? Which is paired and which forms a complete ring? |
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Definition
-epiglottis: shape = flap, composition = elastic cartilage, position = entry to larynx
-thyroid cartilages: shape = U shaped and large, composition = hyaline cartilage, position = cradles larynx
-cricoid cartilages: shape = ring, composition = hyaline cartilage, position = surrounds larynx, wide dorsally to furnish attachemtn for the cricoarytenoideus dorsalis m.
-arytenoid cartilage: shape=small and triangular, composition = hyaline cartilage, position = ventral angle is the vocal process to which the vocal ligament and vocalis m. attaches, lateral angle is the muscular process to which the cricoarytenoiodeus dorsalis m. attches, articulates with cricoid cartilage
-arytenoid is paired
-cricoid forms a complete ring |
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Term
| 13. What are 2 unique features of the equine thyroid cartilage and what is their clinical significance? |
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Definition
1. There is a prominent thyroid notch of the ventral aspect of the thyroid cartilage. This notch divides the thyroid cartilage into left and right parts which are joined cranially by a narrow connecting portion, which is ossified to strengthen their connection. Clinically, the thyroid notch is a useful location for entry into the larynx for ventriculectomy (aka roaring surgery)
2. I guess that there is an ossified portion is the second unique feature. Does anyone have any input? |
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Term
| 14. Why is the respiratory tract lined with cartilage from nostril to small bronchioles. |
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Definition
| -The respiratory tract is lined with cartilage from nostril to small bronchioles because it needs to maintain patency (unobstructed; open) of the airways. |
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Term
| 15. What is the relationship of vocal folds to the laryngeal ventricle? |
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Definition
| - The vocal folds are related to the laryngeal ventricle b/c animals with true vocal folds have ventricles. The mucosa from the vocal folds must “curve cranially” so it will be able to reach the epiglottis, as it curves forward it creates a laryngeal ventricle. |
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Term
| 16. True vocal folds and laryngeal ventricles are found in which domestic species? What is found in other species and how does this effect phonation (sound production)? |
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Definition
-True vocal folds and laryngeal ventricle: human, dog, horse, pig
Ruminants and cat have vocal ridge=softer vocalization than animals with true vocal folds |
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Term
| 17. What are the major muscles of the larynx, their function, and nerve supply? |
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Definition
-Cricoarytenoidus dorsalis m.
F: dialate the glottis, pulls the vocal folds lateral
N: Reccurent laryngeal nerve
-Cricoarytenoideus lateralis m.
F: constricts the glottis, pulls vocal folds medially
N: Reccurent laryngeal
-Vocalis muscle
F: Relaxes the vocal fold, pulls arytenoid cartilage downward
N: Reccurent laryngeal nerve
-Cricothyroidius muscle
F: ?
N: Cranial laryngeal nerve
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Term
| 18. What is the afferent nerve of the gag reflex that occurs when foreign material enters the larynx? |
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Definition
| -Cranial laryngeal nerve is the afferent nerve of the gag reflex for when foreign material gets in the larynx. |
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Term
| 19. Why is roaring called laryngeal hemiplegia and what anatomic differences in the path of the laryngeal nerve supply accounts for this? |
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Definition
| - Roaring is paralysis of the larynx due to recurrent laryngeal nerve damage. Most of the cases are left side only (hemiplegia). So…it affects the larynx (laryngeal) and mainly the left side (hemiplegia). It is mostly on the left because the intrathoracic course of the recurrent nerve differs from left to right…the left side is more susceptible. |
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