WikiVet English - User contributions [en]

Musculoskeletal Diseases

2010-06-03T15:45:25Z

Amy: /* Lameness of the Foot */

{{toplink
|linkpage=WikiClinical
|linktext=WikiClinical
|pagetype =Clinical
}}
<br>
* [[Lameness Examinations]]
* [[Equine Nerve Blocks]]
* [[First Aid and Transport of the Acutely Lame Horse]]

==Bone Disease==

* [[Bone Neoplasms]]
* [[Canine Elbow Dysplasia]]
* [[Developmental Musculoskeletal Disorders]]
* [[Fractures]]
* [[Hip Dysplasia]]
* [[Limb Deformity - Small Animal]]
* [[Miscellaneous Bone Disorders]]
* [[Nutritional and Metabolic Bone Diseases - Small Animal]]
* [[Osteochondrosis]]
* [[Osteomyelitis]]

==Joint Disease==

* [[Dislocations/Subluxations - Bovine]]
* [[Immune-mediated Joint Disease]]
* [[Joint Luxation - Small Animal]]
* [[Osteoarthritis]]
* [[Salvage Procedures]]
* [[Septic Arthritis]]
* [[Sprains - Small Animal]]

==Muscular Disease==
* [[Canine Muscular Diseases]]
* [[Equine Rhabdomyolysis Syndrome]]
* [[Feline Muscular Diseases]]
* [[Fibrotic Myopathy - Equine | Fibrotic Myopathy]]
* [[Stringhalt]]
* [[The Exhausted Horse]]

==Lameness of the Foot==

* [[Claw Capsule (Horn) Lesions]]
* [[Coffin Joint Disorders]]
* [[Hoof Disorders]]
* [[Laminae Disorders - Equine Lameness]]
* [[Navicular Syndrome]]
* [[Other Foot Lesions - Bovine]]
* [[Pedal Bone Disorders]]
* [[Skin and Interdigital Space Lesions]]
* [[Solar Soft Tissue Disorders - Equine Lameness]]
* [[Equine Laminits]]

==Lameness of the Leg==

* [[Contracted Tendons]]
* [[Nerve Paralysis - Bovine]]
* [[Patellar Locking - Equine]]
* [[Tendon Injuries - Equine]]
* [[Tendon Sheaths and Bursae Disorders - Equine]]

Laminitis - Horse

2010-06-03T15:44:36Z

Amy:

[[Category:WikiClinical_Equine]]
[[Category:Equine Lameness]]
[[Category:Equine Laminitis]]
{{horse}}
{{review}}

== Introduction ==

Laminits is a common and debilitating condition of horses cause by separation of the laminae of the hoof. It can be acute or chronic and can result in the horse being put down. To revise the anatomy of the hoof see [[Equine Phalanges - Anatomy & Physiology]]

== Etiology ==

Acute degeneration of the sensitive primary and secondary Laminae. The cause for this is unknown.

== Epidemiology==

=== Increased Risk Factors ===
* Obesity
* Access to lush pastures
* Grain overload (Ingestion of large quantities of soluble carbohydrates)
* Retained Placenta
* Colic and Diarrhoea
* Systemic Illness
* Animals having little exercise
* [[Pituitary Pars Intermedia Dysfunction / Equine Cushing's]]
* Trauma/excessive work on hard surfaces
* Increased weight bearing on one limb

== Pathogenesis ==

The separation of the sensitive laminae (originated from the third phalanx/pedal bone) from the laminae lining the inside surface of the hoof.

This allows the pedal bone to '''rotate''' within the hoof capsule and come to rest on the sole. This causes the sole to be pushed downwards and at the toe the pedal bone mat penetrate the sole.

Rotation occurs due to torque from the deep digital flexor tendon.

Also due to the weight of the animal the pedal bone can '''sink''' (displace ventrally). The bone may rotate, sink or both.

Serum accumulates in the space between the laminae and can breakdown the white line.

=== Mechanism of Separation of the Laminae ===

The mechanism is unknown but theories are:
* Ischaemia and necrosis. Ischaemia may be caused by:
** Vasoconsriction
** Arterio-venous shunts
** Interstitial Oedema
** A mixture of the above

* Inflammation and then degeneration of the sensitive laminae

* Enzymatic digestion of laminae by Matrix Metalloproteins (MMPs)

* Abnormalities in the hoof metabolism or corticosteriods (Endogenous cortisol or iatrogenic) which results in increased glucocorticoid activity.

Subsequent to separation of the laminae a '''pain-hypertension-vasoconstiction''' cycle will occur in acute cases
* Pain causes:
** Release of vasoconstictors (catecholamines, angiotensin II, vasopressin)
* Vasoconstriction causes a reduced blood flow to the foot and systemic hypertension.

== Clinical Signs ==

=== Acute Disease ===

* Develops Rapidly
* Most commonly in the front feet
* Mild or early disease can be seen as reluctance to move and frequent shifting of weight
* Characteristic gait
* If more severe the horse may be:
** Unwilling to move or pick up it's feet
** Show signs of pain (Anxiety, sweating, increased heart and respiration rate)
** Characteristic posture which looks like the horse is standing on its heels, all feet are placed forward of their normal position, the head is low and the back is arched
** Occasionally there may be serum like exudate at the coronary band and the hoof may become detached and shed. Although this indicated a very severe case with good and dedicated owners, vets and farriers who are prepared for the time and cost of treatment the horse can survive sloughing of the hoof and go back to normal work.

=== Chronic Disease ===

Separation of the laminae and sinking and/or rotation of the pedal bone have occurred. The sole has dropped. The hoof wall spreads which results in marked transverse ridges on the hoof. Also the angle of the hoof as viewed laterally decreases. Degeneration of the white line may allow for infection to enter. The pedal bone may become septic. The Animal may become lame with exercise and have repeated bouts of mild laminitis.

== Diagnosis ==

* Pain on palpation around the coronet
* Marked withdrawal in response to hoof testers
* Increased height and strength of pulse in the palmer digital artery
* If the pedal bone has sunk a concavity may be palpable at the junction of the coronet

=== Radiography ===

Radiographs should be taken of front feet or all feet if all legs are affected. A metal strip should be placed on the dorsal wall of the hoof and the sole should be maked with a similar metal strip or a pin can be used. They the angle of the pedal bone in relation to the hoof can then be analysed and the radiograph should be shown to the farrier who is working with you on the case for corrective farriery. Radiographs are essential for prognosis.
You should measure:
* Distance between the top of the hoof wall the top of the extensor process of pedal bone
* Distance between dorsal hoof wall and dorsal cortex of pedal bone

Radiographic changes:
* If mild or acute may show no changes
* May show rotation of the pedal bone as a tilting of the distal aspect towards the sole
* Serum build up may be evident as a radiolucent line between the dorsal hoof wall and the pedal bone

== Prognosis ==

The worse the rotation of the pedal bone the less chance of returning to athletic function or even to becoming pain free.

== Differential Diagnosis ==

Symptoms of the following diseases can be similar but there is no pain in the feet:
* [[Equine Rhabdomyolysis Syndrome]]
* [[Clostridium tetani|Tetanus]]
* Colic
* Spinal Ataxia

== Treatment ==

Acute laminitis is an '''emergency'''. Box rest is an important part of treatment and return to work should be very gradual.

Aims:
* Removing inciting cause
* Relieve pain and reduce inflammation
* Dilate blood vessels in the foot
* Prevent microthrombi formation
* Prevent rotation or sinking of the pedal bone
* Promote hoof growth

Analgesics, mainly [[NSAIDs]] (Phenylbutazone) are the main treatment. It may also help break the theorised pain-hypertension-vasoconstriction cycle.
Other available NSAIDs are Flunixin Meglumine, Ketoprofen and Dimethyl Sulfoxide.
Vasodilators and anticoagulants are also optional add on drugs, depending on the case.

Mechanical support is important and may provide some pain relief and help prevent rotation or sinking of the pedal bone. It can be done with polystyrene or other packing materials or keeping the animal on soft, deep bedding. Elevating the heel with a wedge or wedge shoe may be useful to take off some of the strain on the deep digital flexor tendon and help to reduce rotation. The farrier will be able to help here with the use of egg bar, heart bar and plastic shoes.

Treatment should be monitored physically and radiographically.

Laminitis - Horse

2010-04-02T18:31:16Z

Amy:

[[Category:WikiClinical_Equine]]
{{horse}}
{{review}}

== Introduction ==

Laminits is a common and debilitating condition of horses cause by separation of the laminae of the hoof. It can be acute or chronic and can result in the horse being put down. To revise the anatomy of the hoof see [[Equine Phalanges - Anatomy & Physiology]]

== Etiology ==

Acute degeneration of the sensitive primary and secondary Laminae. The cause for this is unknown.

== Epidemiology==

=== Increased Risk Factors ===
* Obesity
* Access to lush pastures
* Grain overload (Ingestion of large quantities of soluble carbohydrates)
* Retained Placenta
* Colic and Diarrhoea
* Systemic Illness
* Animals having little exercise
* [[Pituitary Pars Intermedia Dysfunction / Equine Cushing's]]
* Trauma/excessive work on hard surfaces
* Increased weight bearing on one limb

== Pathogenesis ==

The separation of the sensitive laminae (originated from the third phalanx/pedal bone) from the laminae lining the inside surface of the hoof.

This allows the pedal bone to '''rotate''' within the hoof capsule and come to rest on the sole. This causes the sole to be pushed downwards and at the toe the pedal bone mat penetrate the sole.

Rotation occurs due to torque from the deep digital flexor tendon.

Also due to the weight of the animal the pedal bone can '''sink''' (displace ventrally). The bone may rotate, sink or both.

Serum accumulates in the space between the laminae and can breakdown the white line.

=== Mechanism of Separation of the Laminae ===

The mechanism is unknown but theories are:
* Ischaemia and necrosis. Ischaemia may be caused by:
** Vasoconsriction
** Arterio-venous shunts
** Interstitial Oedema
** A mixture of the above

* Inflammation and then degeneration of the sensitive laminae

* Enzymatic digestion of laminae by Matrix Metalloproteins (MMPs)

* Abnormalities in the hoof metabolism or corticosteriods (Endogenous cortisol or iatrogenic) which results in increased glucocorticoid activity.

Subsequent to separation of the laminae a '''pain-hypertension-vasoconstiction''' cycle will occur in acute cases
* Pain causes:
** Release of vasoconstictors (catecholamines, angiotensin II, vasopressin)
* Vasoconstriction causes a reduced blood flow to the foot and systemic hypertension.

== Clinical Signs ==

=== Acute Disease ===

* Develops Rapidly
* Most commonly in the front feet
* Mild or early disease can be seen as reluctance to move and frequent shifting of weight
* Characteristic gait
* If more severe the horse may be:
** Unwilling to move or pick up it's feet
** Show signs of pain (Anxiety, sweating, increased heart and respiration rate)
** Characteristic posture which looks like the horse is standing on its heels, all feet are placed forward of their normal position, the head is low and the back is arched
** Occasionally there may be serum like exudate at the coronary band and the hoof may become detached and shed. Although this indicated a very severe case with good and dedicated owners, vets and farriers who are prepared for the time and cost of treatment the horse can survive sloughing of the hoof and go back to normal work.

=== Chronic Disease ===

Separation of the laminae and sinking and/or rotation of the pedal bone have occurred. The sole has dropped. The hoof wall spreads which results in marked transverse ridges on the hoof. Also the angle of the hoof as viewed laterally decreases. Degeneration of the white line may allow for infection to enter. The pedal bone may become septic. The Animal may become lame with exercise and have repeated bouts of mild laminitis.

== Diagnosis ==

* Pain on palpation around the coronet
* Marked withdrawal in response to hoof testers
* Increased height and strength of pulse in the palmer digital artery
* If the pedal bone has sunk a concavity may be palpable at the junction of the coronet

=== Radiography ===

Radiographs should be taken of front feet or all feet if all legs are affected. A metal strip should be placed on the dorsal wall of the hoof and the sole should be maked with a similar metal strip or a pin can be used. They the angle of the pedal bone in relation to the hoof can then be analysed and the radiograph should be shown to the farrier who is working with you on the case for corrective farriery. Radiographs are essential for prognosis.
You should measure:
* Distance between the top of the hoof wall the top of the extensor process of pedal bone
* Distance between dorsal hoof wall and dorsal cortex of pedal bone

Radiographic changes:
* If mild or acute may show no changes
* May show rotation of the pedal bone as a tilting of the distal aspect towards the sole
* Serum build up may be evident as a radiolucent line between the dorsal hoof wall and the pedal bone

== Prognosis ==

The worse the rotation of the pedal bone the less chance of returning to athletic function or even to becoming pain free.

== Differential Diagnosis ==

Symptoms of the following diseases can be similar but there is no pain in the feet:
* [[Equine Rhabdomyolysis Syndrome]]
* [[Clostridium species|Tetanus]]
* Colic
* Spinal Ataxia

== Treatment ==

Acute laminitis is an '''emergency'''. Box rest is an important part of treatment and return to work should be very gradual.

Aims:
* Removing inciting cause
* Relieve pain and reduce inflammation
* Dilate blood vessels in the foot
* Prevent microthrombi formation
* Prevent rotation or sinking of the pedal bone
* Promote hoof growth

Analgesics, mainly [[NSAIDs]] (Phenylbutazone) are the main treatment. It may also help break the theorised pain-hypertension-vasoconstriction cycle.
Other available NSAIDs are Flunixin Meglumine, Ketoprofen and Dimethyl Sulfoxide.
Vasodilators and anticoagulants are also optional add on drugs, depending on the case.

Mechanical support is important and may provide some pain relief and help prevent rotation or sinking of the pedal bone. It can be done with polystyrene or other packing materials or keeping the animal on soft, deep bedding. Elevating the heel with a wedge or wedge shoe may be useful to take off some of the strain on the deep digital flexor tendon and help to reduce rotation. The farrier will be able to help here with the use of egg bar, heart bar and plastic shoes.

Treatment should be monitored physically and radiographically.

Laminitis - Horse

2010-04-02T18:30:29Z

Amy:

[[Category:WikiClinical_Equine]]
{{horse}}
{{unfinished}}

== Introduction ==

Laminits is a common and debilitating condition of horses cause by separation of the laminae of the hoof. It can be acute or chronic and can result in the horse being put down. To revise the anatomy of the hoof see [[Equine Phalanges - Anatomy & Physiology]]

== Etiology ==

Acute degeneration of the sensitive primary and secondary Laminae. The cause for this is unknown.

== Epidemiology==

=== Increased Risk Factors ===
* Obesity
* Access to lush pastures
* Grain overload (Ingestion of large quantities of soluble carbohydrates)
* Retained Placenta
* Colic and Diarrhoea
* Systemic Illness
* Animals having little exercise
* [[Pituitary Pars Intermedia Dysfunction / Equine Cushing's]]
* Trauma/excessive work on hard surfaces
* Increased weight bearing on one limb

== Pathogenesis ==

The separation of the sensitive laminae (originated from the third phalanx/pedal bone) from the laminae lining the inside surface of the hoof.

This allows the pedal bone to '''rotate''' within the hoof capsule and come to rest on the sole. This causes the sole to be pushed downwards and at the toe the pedal bone mat penetrate the sole.

Rotation occurs due to torque from the deep digital flexor tendon.

Also due to the weight of the animal the pedal bone can '''sink''' (displace ventrally). The bone may rotate, sink or both.

Serum accumulates in the space between the laminae and can breakdown the white line.

=== Mechanism of Separation of the Laminae ===

The mechanism is unknown but theories are:
* Ischaemia and necrosis. Ischaemia may be caused by:
** Vasoconsriction
** Arterio-venous shunts
** Interstitial Oedema
** A mixture of the above

* Inflammation and then degeneration of the sensitive laminae

* Enzymatic digestion of laminae by Matrix Metalloproteins (MMPs)

* Abnormalities in the hoof metabolism or corticosteriods (Endogenous cortisol or iatrogenic) which results in increased glucocorticoid activity.

Subsequent to separation of the laminae a '''pain-hypertension-vasoconstiction''' cycle will occur in acute cases
* Pain causes:
** Release of vasoconstictors (catecholamines, angiotensin II, vasopressin)
* Vasoconstriction causes a reduced blood flow to the foot and systemic hypertension.

== Clinical Signs ==

=== Acute Disease ===

* Develops Rapidly
* Most commonly in the front feet
* Mild or early disease can be seen as reluctance to move and frequent shifting of weight
* Characteristic gait
* If more severe the horse may be:
** Unwilling to move or pick up it's feet
** Show signs of pain (Anxiety, sweating, increased heart and respiration rate)
** Characteristic posture which looks like the horse is standing on its heels, all feet are placed forward of their normal position, the head is low and the back is arched
** Occasionally there may be serum like exudate at the coronary band and the hoof may become detached and shed. Although this indicated a very severe case with good and dedicated owners, vets and farriers who are prepared for the time and cost of treatment the horse can survive sloughing of the hoof and go back to normal work.

=== Chronic Disease ===

Separation of the laminae and sinking and/or rotation of the pedal bone have occurred. The sole has dropped. The hoof wall spreads which results in marked transverse ridges on the hoof. Also the angle of the hoof as viewed laterally decreases. Degeneration of the white line may allow for infection to enter. The pedal bone may become septic. The Animal may become lame with exercise and have repeated bouts of mild laminitis.

== Diagnosis ==

* Pain on palpation around the coronet
* Marked withdrawal in response to hoof testers
* Increased height and strength of pulse in the palmer digital artery
* If the pedal bone has sunk a concavity may be palpable at the junction of the coronet

=== Radiography ===

Radiographs should be taken of front feet or all feet if all legs are affected. A metal strip should be placed on the dorsal wall of the hoof and the sole should be maked with a similar metal strip or a pin can be used. They the angle of the pedal bone in relation to the hoof can then be analysed and the radiograph should be shown to the farrier who is working with you on the case for corrective farriery. Radiographs are essential for prognosis.
You should measure:
* Distance between the top of the hoof wall the top of the extensor process of pedal bone
* Distance between dorsal hoof wall and dorsal cortex of pedal bone

Radiographic changes:
* If mild or acute may show no changes
* May show rotation of the pedal bone as a tilting of the distal aspect towards the sole
* Serum build up may be evident as a radiolucent line between the dorsal hoof wall and the pedal bone

== Prognosis ==

The worse the rotation of the pedal bone the less chance of returning to athletic function or even to becoming pain free.

== Differential Diagnosis ==

Symptoms of the following diseases can be similar but there is no pain in the feet:
* [[Equine Rhabdomyolysis Syndrome]]
* [[Clostridium species|Tetanus]]
* Colic
* Spinal Ataxia

== Treatment ==

Acute laminitis is an '''emergency'''. Box rest is an important part of treatment and return to work should be very gradual.

Aims:
* Removing inciting cause
* Relieve pain and reduce inflammation
* Dilate blood vessels in the foot
* Prevent microthrombi formation
* Prevent rotation or sinking of the pedal bone
* Promote hoof growth

Analgesics, mainly [[NSAIDs]] (Phenylbutazone) are the main treatment. It may also help break the theorised pain-hypertension-vasoconstriction cycle.
Other available NSAIDs are Flunixin Meglumine, Ketoprofen and Dimethyl Sulfoxide.
Vasodilators and anticoagulants are also optional add on drugs, depending on the case.

Mechanical support is important and may provide some pain relief and help prevent rotation or sinking of the pedal bone. It can be done with polystyrene or other packing materials or keeping the animal on soft, deep bedding. Elevating the heel with a wedge or wedge shoe may be useful to take off some of the strain on the deep digital flexor tendon and help to reduce rotation. The farrier will be able to help here with the use of egg bar, heart bar and plastic shoes.

Treatment should be monitored physically and radiographically.

Laminitis - Horse

2010-04-02T16:35:24Z

Amy:

[[Category:WikiClinical_Equine]]
{{horse}}
{{unfinished}}

== Introduction ==

Laminits is a common and debilitating condition of horses cause by separation of the laminae of the hoof. It can be acute or chronic and can result in the horse being put down. To revise the anatomy of the hoof see [[Equine Phalanges - Anatomy & Physiology]]

== Etiology ==

Acute degeneration of the sensitive primary and secondary Laminae. The cause for this is unknown.

== Epidemiology==

=== Increased Risk Factors ===
* Obesity
* Access to lush pastures
* Grain overload (Ingestion of large quantities of soluble carbohydrates)
* Retained Placenta
* Colic and Diarrhoea
* Systemic Illness
* Animals having little exercise
* [[Pituitary Pars Intermedia Dysfunction / Equine Cushing's]]
* Trauma/excessive work on hard surfaces
* Increased weight bearing on one limb

== Pathogenesis ==

The separation of the sensitive laminae (originated from the third phalanx/pedal bone) from the laminae lining the inside surface of the hoof.

This allows the pedal bone to '''rotate''' within the hoof capsule and come to rest on the sole. This causes the sole to be pushed downwards and at the toe the pedal bone mat penetrate the sole.

Rotation occurs due to torque from the deep digital flexor tendon.

Also due to the weight of the animal the pedal bone can '''sink''' (displace ventrally). The bone may rotate, sink or both.

Serum accumulates in the space between the laminae and can breakdown the white line.

=== Mechanism of Separation of the Laminae ===

The mechanism is unknown but theories are:
* Ischaemia and necrosis. Ischaemia may be caused by:
** Vasoconsriction
** Arterio-venous shunts
** Interstitial Oedema
** A mixture of the above

* Inflammation and then degeneration of the sensitive laminae

* Enzymatic digestion of laminae by Matrix Metalloproteins (MMPs)

* Abnormalities in the hoof metabolism or corticosteriods (Endogenous cortisol or iatrogenic) which results in increased glucocorticoid activity.

Subsequent to separation of the laminae a '''pain-hypertension-vasoconstiction''' cycle will occur in acute cases
* Pain causes:
** Release of vasoconstictors (catecholamines, angiotensin II, vasopressin)
* Vasoconstriction causes a reduced blood flow to the foot and systemic hypertension.

== Clinical Signs ==

=== Acute Disease ===

* Develops Rapidly
* Most commonly in the front feet
* Mild or early disease can be seen as reluctance to move and frequent shifting of weight
* Characteristic gait
* If more severe the horse may be:
** Unwilling to move or pick up it's feet
** Show signs of pain (Anxiety, sweating, increased heart and respiration rate)
** Characteristic posture which looks like the horse is standing on its heels, all feet are placed forward of their normal position, the head is low and the back is arched
** Occasionally there may be serum like exudate at the coronary band and the hoof may become detached and shed. Although this indicated a very severe case with good and dedicated owners, vets and farriers who are prepared for the time and cost of treatment the horse can survive sloughing of the hoof and go back to normal work.

=== Chronic Disease ===

Separation of the laminae and sinking and/or rotation of the pedal bone have occurred. The sole has dropped. The hoof wall spreads which results in marked transverse ridges on the hoof. Also the angle of the hoof as viewed laterally decreases. Degeneration of the white line may allow for infection to enter. The pedal bone may become septic. The Animal may become lame with exercise and have repeated bouts of mild laminitis.

== Diagnosis ==

* Pain on palpation around the coronet
* Marked withdrawal in response to hoof testers
* Increased height and strength of pulse in the palmer digital artery
* If the pedal bone has sunk a concavity may be palpable at the junction of the coronet

=== Radiography ===

Radiographs should be taken of front feet or all feet if all legs are affected. A metal strip should be placed on the dorsal wall of the hoof and the sole should be maked with a similar metal strip or a pin can be used. They the angle of the pedal bone in relation to the hoof can then be analysed and the radiograph should be shown to the farrier who is working with you on the case for corrective farriery.

* If mild or acute may show no changes
* May show rotation of the pedal bone as a tilting of the distal aspect towards the sole
* Serum build up may be evident as a radiolucent line between the dorsal hoof wall and the pedal bone

Laminitis - Horse

2010-04-02T15:41:18Z

Amy: Created page with 'Category:WikiClinical_Equine {{horse}} {{unfinished}} == Introduction == Laminits is a common and debilitating condition of horses. To revise the anatomy of the hoof see […'

[[Category:WikiClinical_Equine]]
{{horse}}
{{unfinished}}

== Introduction ==

Laminits is a common and debilitating condition of horses. To revise the anatomy of the hoof see [[Equine Phalanges - Anatomy & Physiology]]

== Etiology ==

Acute degeneration of the sensitive primary and secondary Laminae

File:Horse-logo.png

2010-04-02T15:39:16Z

Amy: Blanked the page

File:Horse-logo.png

2010-04-02T15:38:37Z

Amy:

Pharynx - Anatomy & Physiology

2010-03-27T12:13:05Z

Amy: /* Equine */

{{review}}

{{toplink
|linkpage =Cardiorespiratory System - Anatomy & Physiology
|linktext =Cardiorespiratory System
|maplink = Cardiorespiratory System (Content Map) - Anatomy & Physiology
|pagetype =Anatomy
|sublink1=Musculoskeletal System - Anatomy & Physiology
|subtext1=MUSCULOSKELETAL SYSTEM
}}
<br>

==Introduction==
[[Image:Developing Head.jpg|thumb|right|150px|Developing Head - Copyright RVC]]
The pharynx is part of both the [[Cardiorespiratory System - Anatomy & Physiology|respiratory]] and [[Alimentary - Anatomy & Physiology|digestive]] system. Both systems have entrances to the pharynx but they are separated from each other by the [[Soft Palate - Anatomy & Physiology|soft palate]].

During exercise or during respiratory distress, the mouth can be used as an additional opening of the respiratory system and then the [[Oral Cavity - Oropharynx - Anatomy & Physiology|oropharynx]] also becomes an air-way.

The pharynx can be split into different regions- the [[Oral Cavity - Oropharynx - Anatomy & Physiology|oropharynx]], [[Larynx - Anatomy & Physiology#Laryngeal Pharynx|laryngeal pharynx]] (sometimes referred to as the oesophageal pharynx) and the [[Nasopharynx - Anatomy & Physiology|nasopharynx]]
[[Image:Nasopharynx.jpg|thumb|right|150px|Nasopharynx Anatomy - Copyright RVC]]
==Structure and Function==

*Opening of the [[Larynx - Anatomy & Physiology|larynx]] is on the floor of the pharynx

*Caudal and dorsal to the laryngeal opening is the opening into the [[Oesophagus - Anatomy & Physiology|oesophagus]]

*In the dorsal region of the [[Nasopharynx - Anatomy & Physiology|nasopharynx]] there are paired openings into the Auditory (Eustacian) Tubes

*The lining of the middle ear cavity and auditory tube is continuous with that of the [[Nasopharynx - Anatomy & Physiology|nasopharynx]]

*Located between the base of the skull and the first two cervical vertebrae dorsally

*[[Larynx - Anatomy & Physiology|larynx]] ventrally

*[[Skull and Facial Muscles - Anatomy & Physiology#Mandible (mandibula)|Mandible]], pterygoid muscles and [[Hyoid Apparatus - Anatomy & Physiology|hyoid apparatus]] laterally

*Walls contain striated muscle
[[Image:Pharynx Anatomy.jpg|thumb|right|150px|Pharynx Labelled - Copyright C.Clarkson and T.F.Fletcher University of Minnesota]]
*During [[Deglutition|swallowing]] the [[Soft Palate - Anatomy & Physiology|soft palate]] is raised which divides the pharynx into dorsal and ventral sections
**Laterally, two pairs of palatopharyngeal arches are present from the [[Soft Palate - Anatomy & Physiology|soft palate]] to the [[Oesophagus - Anatomy & Physiology|oesophagus]]
**The dorsal compartment is the [[Nasopharynx - Anatomy & Physiology|nasopharynx]]
**The rostral compartment is the [[Oral Cavity - Oropharynx - Anatomy & Physiology|oropharynx]]

*The [[Larynx - Anatomy & Physiology#Laryngeal Pharynx|laryngeal pharynx]] is separated from the [[Oral Cavity - Oropharynx - Anatomy & Physiology|oropharynx]] by the [[Epiglottis|epiglottis]]

*[[Tonsils - Anatomy & Physiology|Tonsils]] are present on the lateral walls of the [[Oral Cavity - Oropharynx - Anatomy & Physiology|oropharynx]]
**Covered by flaps of mucosa
**Partially visible in the open mouth

*The pharynx plays an important role in [[Deglutition|deglutition]]
[[Image:Soft Palate Separating Pharyngeal Cavities.jpg|thumb|right|150x|Soft palate dividing the oropharynx and the nasopharynx - Copyright RVC]]

==Musculature==

===Muscles that constrict===

*Run dorsally to roof of pharynx

*Rostral constrictor muscles are the '''hyopharyngeous''', '''pterygopharyngeous''' and the '''palatopharyngeous muscles'''
**Originate from the [[Tonsils - Anatomy & Physiology#Pterygoid Bone (os pterygoideum)|pterygoid]] region of the skull and the aponeurosis of the [[Soft Palate - Anatomy & Physiology|soft palate]]
**Shorten the pharynx

*Middle constictor muscle is the '''thyopharyngeous muscle'''
**Origniates from the [[Hyoid Apparatus - Anatomy & Physiology|hyoid bone]]

*Caudal constictor muscles are the '''cricopharyngeous muscle'''
**Originates from the [[Larynx - Anatomy & Physiology#Thyroid Cartilage|thyroid cartilage]] of the [[Larynx - Anatomy & Physiology|larynx]]

===Muscles that dilate===

*Enclose pharynx laterally and dorsally

*Dilator muscle is the '''stylopharyngeous muscle'''

*Originates from the [[Hyoid Apparatus - Anatomy & Physiology|hyoid apparatus]]

*Widens the rostral pharynx

===Muscles that shorten===

*The '''pterygopharyngeal muscle''' and '''palatopharyngeal muscle''' shorten the pharynx

*Enclose pharynx laterally and dorsally

===Muscles that close the Pharyngeal Arch===

*The '''palatopharyngeous muscle''' also closes the pharyngeal arch

==Innervation==

*Pharyngeal muscles arise from arch 4

*Pharyngeal branch of the vagus nerve ([[Cranial Nerves - Anatomy & Physiology|CN X]]) from the cranial root of the accessory nerve ([[Cranial Nerves - Anatomy & Physiology|CN XI]])

*Stylopharyngeous muscle comes from arch 3 and is innervated by the accessory nerve ([[Cranial Nerves - Anatomy & Physiology|CN XI]])
*Glossopharyngeal nerve ([[Cranial Nerves - Anatomy & Physiology|CN IX]]) supplies taste to the pharynx
[[Image:Pharyngeal Tonsil.jpg|thumb|right|150px|Histology of Pharyngeal Tonsil - Copyright RVC]]
==Histology==

*Fibroelastic aponeurosis supports the mucosa

*[[Nasopharynx - Anatomy & Physiology|nasopharynx]] has pseudostratified columnar epithelium

*[[Oral Cavity - Oropharynx - Anatomy & Physiology|oropharynx]] and the [[Larynx - Anatomy & Physiology#Laryngeal Pharynx|laryngeal pharynx]] have stratified squamous epithelium

*[[Oral Cavity - Oropharynx - Anatomy & Physiology|oropharynx]] and the [[Larynx - Anatomy & Physiology#Laryngeal Pharynx|laryngeal pharynx]] have [[Oral Cavity - Salivary Glands - Anatomy & Physiology|salivary glands]] present
[[Image:Pharynx Anatomy.jpg|thumb|right|150px|Palatine Tonsil - Copyright C.Clarkson and T.F.Fletcher University of Minnesota]]
==Species Differences==

====Canine====
*Single duct connects [[Nasopharynx - Anatomy & Physiology|nasopharynx]] to the [[Nasal cavity - Anatomy & Physiology|nasal cavity]]

*[[Tonsils - Anatomy & Physiology|Tonsils]] are a compact mass which point away from the lumen of the pharynx

====Equine====
*Auditory tube opens into the [[Ear - Anatomy & Physiology#Equine Guttural Pouch|guttural pouch]]

*[[Tonsils - Anatomy & Physiology|Tonsils]] are diffuse and raised slightly

*Horses are unable to breath through the mouth as the free apex of the rostral epiglottis lies dorsal to the soft palate in a normal horse.

====Ruminants====
*[[Tonsils - Anatomy & Physiology|Tonsils]] are a compact mass which point towards the lumen of the pharynx

==Links==

[[Oral Cavity - Oropharynx - Anatomy & Physiology|Oropharynx - Anatomy & Physiology]]

[[Nasopharynx - Anatomy & Physiology]]

[[Larynx - Anatomy & Physiology#Laryngeal Pharynx|laryngeal pharynx]]

[[Pharynx - Musculoskeletal - Flashcards|Pharynx Flashcards]]

Ribs and Sternum - Anatomy & Physiology

2010-03-20T12:24:26Z

Amy: /* Thoracic Musculature */

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|linkpage =Musculoskeletal System - Anatomy & Physiology
|linktext =Musculoskeletal System
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|pagetype =Anatomy
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<br>
=Costae=
[[Image:Thorax skeleton.png|thumb|right|150px|Canine thorax showing placement of mitral valve - Wikimedia Commons 2008]]
*Arranged in pairs and articulate with two successive vertebrae
*Bony dorsal part, body of rib, and ventral costal cartilage
*Increase in length, curvature and amount of cartilage craniocaudally
*Cartilage of last rib may fail to join that of its neighbor: said to be '''floating'''
*Join ventrally on the midline at the '''Sternum''', which is comprised of three parts
**'''Manubrium''': most cranial, projects beyond the first set of ribs and can be palpated
**Body: segmented '''sternebrae''' joined by cartilage in young animals that is later replaced by bone
**'''Xiphoid Cartilage''': caudal end that projects between lower ends of costal arches, providing attachment for the '''linea alba'''
*Costal Joints:
**Costovertebral joint: head of rib articulates with vertebral column, ball and socket with very restricted mobility
**Costotransverse joint: tubercle articulates with vertebra, sliding joint
**Costosternal joints:
***Interchondral joints: asternal ribs, elastic syndesmoses
***Intersternal joints: impermanent synchondroses

=Thoracic Musculature=
[[Image: Cat diaphragm.jpg|thumb|right|150px|Cat diaphragm- Copyright Uwe Gille]]
*Primarily concerned with respiration
**Inspiratory muscles enlarge the thoracic cavity
**Expiratory muscles diminish the cavity and force air out
*The most important thoracic muscle is the '''''Diaphragm''''', which separates the thoracic and abdominal cavities
**Dome-shaped, convex on its cranial surface
**Central tendon forms the vertex
***Neutral position (between full inspiration and full expiration): 6th rib behind the '''olecranon'''
**Attaches via muscular periphery to the costal arch
[[Image: Intercostal.JPG|thumb|right|150px|Intercostal muscles with nerve and vessels- Copyright C. Clarkson and T.F. Fletcher, University of Minnesota]]
**The Diaphragm has three openings:
***'''Aortic hilus''' conveying the aorta, azygous vien, and thoracic duct
***'''Oesophageal hiatus''' conveying the oesophagus, vagal trunks and supplying vessels
***'''Caval foramen''' within central tendon conveying [[Liver - Anatomy & Physiology#Vasculature|caudal vena cava]]
**Innervated by the '''phrenic nerve''', which arises from the caudal cervical nerves (C5-C7)

*''Intercostal muscles''
**External fibers run caudoventrally and internal fibers run cranioventrally
**Each is confined to a single intercostal space
*''Transversus thoracis'' arises from and covers the dorsal sternum and inserts on sternal ribs close to the costochondral junctions
*''Rectus thoracis'' covers the ends of the first four ribs in continuation of the ''rectus abdominus''
*''Serratus dorsalis'' overlies the dorsal aspect of the ribs
*Innervation of these muscles is supplied by the '''Intercostal nerves''', which are ventral branches of the thoracic spinal nerves

=Abdominal Musculature=
*Ventrolateral Muscles: flanks and abdominal floor
**All muscles join via aponeuroses in the '''linea alba''' at midline, which runs from the [[Ribs and Sternum - Anatomy & Physiology#Costae|xiphoid process]] to the [[Pelvis - Anatomy & Physiology#Pelvic Girdle|pelvic symphysis]] via the prepubic tendon, ensheathing the ''rectus abdominus''
**The ''External abdominal oblique'' runs caudoventrally from the lateral surface of the ribs and the lumbar fascia to the linea alba. Its caudal border is thickened to form the inguinal ligament and a slit in its aponeurosis forms the superficial inguinal ring.
**The ''Internal abdominal oblique'' runs cranioventrally from the tuber coxae and the thoracolumbar fascia to the linea alba. It forms the cranial border of the inguinal canal.
**The ''Transversus abdominus'' is the deepest muscle of the flank, running dorsoventrally from the inner surface of the last ribs and the transverse processes of the lumbar vertebrae.
**The ''Rectus abdominus'' forms a broad band parallel to the linea alba, arising from the ventral costal cartilages and inserting on the prepubic tendon. It also forms the medial border of the inguinal canal.
*Sublumbar Muscles:
**''Psoas minor'': stabilizer of the vertebral column, may also rotate the pelvis at the sacroiliac joint
**''Psoas major'' and ''Iliacus'':

=Video Links=
*[http://stream2.rvc.ac.uk/Frean/Pony/abdominal_layers.wmv Abdominal Musculature, Pony Dissection, Copyright RVC 2008]
*[http://stream2.rvc.ac.uk/Frean/sheep/AbdominalWall.wmv Abdominal Wall, Sheep Dissection, Copyright RVC 2008]