Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

3. Equine 2 > Common Orthopedic Diseases > Flashcards

Common Orthopedic Diseases Flashcards

1
Q

Developmental Orthopedic Disease

A

Developmental Osteochondrosis
- Osteochondritis dissecans (“OCD”)
- Subchondral bone cysts
- Physeal dysplasia
<><>
- angular limb deformities
<><>
- flexural deformities
<><>
- cervical vertebral malformation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

developmental osteochondrosis terminology:
- Osteochondrosis
- Osteochondritis dissecans (“OCD”)
- Osteochondral fragment

A

§ Osteochondrosis = a disorder of bone and cartilage
(developmental or traumatic/degenerative).
<><>
§ Osteochondritis dissecans (“OCD”) = a flap-like lesion of abnormal articular cartilage or cartilage + bone.
<><>
§ Osteochondral fragment = a detached fragment of articular cartilage and bone (traumatic or developmental).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Developmental Osteochondrosis
Pathophysiology:

A

A failure of normal endochondral ossification.
Ø Physeal or articular-epiphyseal complex.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Review – how does bone grow?:

A
  • Primary Center of ossification = diaphysis
  • Secondary center of ossification = epiphysis (each end)
  • Inbetween = epiphyseal plate – continues to form cartilage that is replaced with bone
  • Once bone from primary & secondary center meets, only physeal scar left
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

in normal bone formation, after ossification of diaphysis and epiphyses, where does hyaline cartilage remain?

A

only in the epiphyseal plates and articular cartilages

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Developmental Osteochondrosis - pathogenesis

A
  • Abnormal chondrocyte differentiation.
  • Synthesis of defective extracellular matrix.
  • Persistence of chondrocytes in mid-to-late hypertrophic zone.
  • Failure of vascular in-growth and ossification.
  • Thickening and retention of the hypertrophic zone of the growth cartilage.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what are the ‘zones’ of development, as bone replaces hyaline cartilage in normal development?

A
  • Resting zone = normal hyaline cartilage
  • Proliferative zone = chondrocytes > rapid proliferate = cell columns
  • Zone of maturation/hypertrophy – big cells & secrete ALK Phos
  • Zone of calcification/ossification – chondrocytes die & osteoblasts invade
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Developmental Osteochondrosis
2 Basic Manifestations when articular-epiphyseal complex affected:

A
  • Osteochondritis dissecans (more common?)
  • Subchondral bone cysts
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Osteochondritis dissecans - what is this

A
  • Flaps or fragments of cartilage or cartilage & bone = OCD lesions.
  • Shear forces may favor formation of OCD lesions.
  • Gliding surfaces.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Subchondral bone cysts - what are these?

A
  • In-folding of defective cartilage = formation of SBC’s.
  • Compressive forces may favor SBC formation.
  • Central weight-bearing regions.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Developmental Osteochondrosis
Etiology:

A

Complex, multifactorial and incompletely understood.
- Growth Rate - High energy diets and rapid growth are associated with OC in some species.
- Dietary Factors - High carbohydrate load. - Low Cu++ (or high Zn++).
- Genetics - High heritability of OC indicated in some studies. - Specific genetic defect not identified.
- Trauma - Not a primary factor, but plays a role in both the pathogenesis of some lesions, and in the precipitation of clinical signs.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

OCD & Subchondral Bone Cysts
General Concepts:
- who gets them?
- clinical signs?
- Dx?
- significance?

A
  • Younger horses → Foals, weanlings, yearlings, 2-year-olds.
  • Clinical Signs → joint effusion and lameness.
    > Joints are not hot and flexion is tolerated.
    > Lameness ranges from subtle-to-moderate (rarely severe).
  • Diagnostic analgesia is rarely necessary.
  • Radiographs are the primary diagnostic modality.
  • Not all OCD & SBC lesions cause lameness or effusion.
    > Often seen as an incidental finding in older horses.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Developmental OC of the Fetlock
Lesions

A
  • OC fragments of proximal palmar/plantar P-1.
  • OCD of distal, dorsal MC-3 & MT-3 (sagihal ridge).
  • SBC’s of distal MC-3 & MT-3.
  • OC fragments of proximal, dorsal P-1.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

OC Fragments of Palmar/Plantar P-1
- 4 Types of Palmar/Plantar Fetlock Fragments:

A

1st Phalanx
- Type 1 - subchondral flattening or separate fragments abaxial to sagittal groove. (intra-articular)
- Type 2 - fragments on the abaxial aspect of the palmar/plantar process. (extra-articular)
<><>
Proximal Sesamoid
- Type 3 - fragments off the distal aspect of the sesamoid bones.
- Type 4 - fragments within the distal sesamoidean ligaments.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

OC Fragments of Palmar/Plantar P-1
- Clinical Signs
- treatment
- prognosis

A
  • Minimal joint effusion (vs. other “OCD” lesions)
  • Lameness, if present, typically only affects the horse at high speed.
    > rarely have clinical signs otherwise
    <><><><>
    Treatment:
  • arthoscopic debridement
    > Either pre-sale or prior to training.
    > When associated with lameness (otherwise dont go in, unless you know where the fragment is, perhaps…)
    <><><><>
    Prognosis
  • Good-to-excellent for most lesions.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

OCD of Distal, Dorsal MC/MT-3
- Sagittal Ridge Lesions divided into 3 Types:

A
  • Type 1 - subchondral flattening.
  • Type 2 - flattening in addition to a bony fragment.
  • Type 3 - loose osseous body within the dorsal joint.
16
Q

OCD of Distal, Dorsal MC/MT-3
- clinical signs
- treatment, based on type
- prognosis

A

Clinical Signs
- Joint effusion is typically the initial clinical sign.
- Lameness tends to be mild.
<><>
Treatment
- Arthroscopic debridement for Types 2 & 3.
- Rest is appropriate treatment for Type 1 lesions.
<><>
Prognosis
- Generally very good (if minimal associated DJD).

17
Q

Subchondral Cysts of MC/MT-3
- how common
- treatment
- prognosis

A
  • Less common than the other lesions in the fetlock joints.
    <><>
    Treatment options:
  • Arthroscopic debridement.
  • Intralesional corticosteroid injection.
  • Intra-articular medication and rest.
    <><>
    -The prognosis for hard athletic use is guarded.
18
Q

OCD of the Tarsus
- lesions – Tarsocrural Joint tibiotarsal joint).

A
  • Cranial, distal, intermediate ridge of the tibia (DIRT).
  • Medial malleolus of the tibia.
  • Lateral trochlear ridge of the talus.
  • Medial trochlear ridge of the talus.
19
Q

OCD of the Tarsus
Clinical Signs
treatment
prognosis

A

Clinical Signs
- Joint effusion is #1.
- Lameness typically does not develop
until horses are in athletic training.
<><>
Treatment
- Arthroscopic debridement.
<><>
Prognosis
- Typically good, if not excellent.
- Prognosis decreases with more extensive disease.
- Also less favorable when degenerative changes have developed.

20
Q

Osteochondrosis of the Stifle
Lesions

A
  • OCD - lateral trochlear ridge of the femur.
  • SBC - medial condyle of the femur > always has compressive forces on it
21
Q

Osteochondrosis of the Stifle
Clinical Signs for OCD lesions:
for SBC lesions:

A

OCD (lateral trochlear ridge of the femur)
- Femoropatellar effusion is a consistent sign.
- Lameness is typically minimal-to-moderate.
<><><>
SBC (medial condyle of the femur)
- Effusion less common with SBC lesions.
- Lameness ranges from mild-to-severe.

22
Q

Osteochondrosis of the Stifle
Treatment for OCD lesions:
for SBC lesions:
convelescence?

A

OCD lesions
- Arthroscopic debridement.
- (Selected cases will improve with long-term rest.)
<><>
SBC’s
- Arthroscopic debridement > only if cyst has wide opening
- Intralesional corticosteroid injection.
- Intra-articular medication and rest.
<><>
- 6 -12 months convalescence is often necessary.

23
Q

Osteochondrosis of the Stifle
Prognosis

A

Depends on severity of lesions and clinical signs.
- Guarded-to-good for OCD lesions.
- Less favourable for SBC’s, in general.

24
Q

Osteochondrosis of the Shoulder
Lesions

A
  • 25% humeral head, 25% glenoid, 50% both sites.
  • OCD lesions on the humeral head.
  • SBC’s in the glenoid.
25
Q

Osteochondrosis of the Shoulder
clinical signs

A
  • Most horses first exhibit lameness as weanlings or yearlings.
  • Lameness ranges from mild-to-severe.
26
Q

Osteochondrosis of the Shoulder
Treatment, prognosis

A
  • Arthroscopic debridement.
  • Rest, ± IA medication.
    <><>
    Prognosis
  • Guarded at best (often poor for hard athletic use).
27
Q

Physeal Dysplasia
a.k.a. “Physitis” or “Epiphysitis”
- pathogenesis, risk factors

A

Pathogenesis: some similarities with articular osteochondrosis.
- Failure of endochondral ossification → widening of the growth plate (physeal complex)
<><>
Similar risk factors:
- Nutritional/metabolic (mineral imbalances, feeds with high glycemic index).
- Genetic predisposition.
- High growth-rate.
- Trauma.

28
Q

physeal dysplasia common locations

A
  • Distal 3rd metacarpal/metatarsal physis.
  • distal radial physis
  • distal tibial physis
  • usually bilateral (or quadrilateral in MC/MT-3)

3. Equine 2 (16 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions