Joint Pathology I Flashcards
What are the three different types of joints?
- Fibrous
- Cartilaginous
- Synovial
What is a fibrous joint?
Bones are united by fibrous tissue
What is syndesmoses?
Adjacent bones are united by an interosseouss ligament or membrane
What are gomphoses?
Joints between the teeth to the mandible/ maxilla
fibrous joint
What are fontanelles?
spaces between the bones of the skull where bone formation is not complete
What is synostosis?
Early fusion of two or more bones of the skull
What is a cartilaginous joint?
Union between bones by hyaline or fibrocartilage
What are the two locations of sympheses?
cartilaginous joint
- Intervertebral discs
- Pubic Sympheses
What makes up a synovial joint?
Bone ends are covered in hyaline and articular cartilage
Why do superficial lacerations not heal properly?
no haemorrhage/ inflammation means it doesn’t heal
How do full depth articular cartilage injuries heal?
- Presence of haemorrhage, inflammatory cells and mesenchymal cells
- Mesenchymal cells start having features of chondrocytes and produce matrix rich proteoglycans
- The defect fills with fibrocartilage
fibrocartilage does not perform as well under mechanical stress
What do large articular cartilage defects progress to?
They progress to degeneration
What is osteochondrosis?
- Focal failure of endochondral ossification
- failure of blood supply of growing cartilage
What are the three forms of osteochondrosis?
- latens
- manifesta
- dissecans
What is latens osteochondrosis?
ischemic cartilage necrosis of growth cartilage, but not articular
failure in vascularisation
What is manifesta osteochondrosis?
retention of necrotic cartilage- failure of endochobdral ossification
devascularised area fails to ossify
What is dissecans osteochondrosis?
cartilage necrosis forms a cleft
Name four potential causes of osteochondrosis
- Genetics
- Trauma
- Nutrition
- Growth rate/ Exercise
What is hip dysplasia?
lack of conformity between femoral head and the acetabulum
What causes hip dysplasia?
Excessive joint laxity + degenerative joint disease
What is the most common skeletal disease of large/ giant breeds of dog
Hip dysplasia
What causes cervical vertebral malformation?
Spinal compression
What are atlantoaxial subluxations?
- Failure of fusion of the odontoid process
- very common in arabian foals
What is arthrogyroposis?
Overextension/ over flexion
What causes arthrogyroposis?
- Lesions of the nervous system in-utero
- Fixations of the joints in a flexed position
What is primary osteoarthrosis?
When there is no apparant predisposing cause (usually in older animals)
What is secondary osteoarthritis?
Underlying abnormality in the joint/ the supporting strcutures
What is fibrillation?
roughening of articular cartilage in weight bearing areas
What is Eburnation?
Articular cartilage is completely absent
Bone then rubs with bone
What is spondylosis?
Formation of osteophytes at ventral and lateral margins of vertebral bodies adjacent to intervertebral bodies
What is fibrinous arthritis commonly associated with?
associated with increased permeability of blood vessels
What is purulent arthritis and what is it commonly associated with?
- Large number of neutrophils in synovial fluid
- Commonly associated with sepsis
What does caprine arthritis look like?
- Carpal hygroma
- Articular cartilage degeneration
- Lymphoplasmacytic arthritis
What is diskospondylitis?
- inflammation of intervertebral disk and adjacent vertebrae
What is articular gout?
Deposition of monosodium urate crystals in joints
therefore leading to granulomatous inflammation
What is pseudogout?
Articular and pararticular deposition of calcium pyrophosphate dihydrate
* goes on to cause granulomatous inflammation
What are the two forms of immune mediated polyarthritis?
Erosive and Non-Erosive
Name 5 developmental diseases of joints
- Osteochondrosis
- Hip Dysplasia
- Cervical vertebral malformation-malarticulation
- Luxations and subluxations
- Abnormal positioning
What is a Chondrodystrophic breed and what is the meaning?
- Higher % of collagen rather than proteoglycans in the nucleus pulposus
- Degeneration of the nucleus pulposus early in life
- also secondary degeneration of the annulus fibrosus
- Predisposes to hansen type I intervertebral disc formation
What is the nucleus pulposus?
the soft, gelatinous central portion of the intervertebral disk that moves within the disk with changes in posture
What is a non-chondrodystrophic breed?
- Degeneration of the nucleus pulposus with age
- Hansen type II herniation
What does the Maedi-Visna virus in sheep cause?
Lymphoplasmacytic synovitis
What is Bursitis?
painful condition that affects the bursae that cushion the bones, tendons and muscles
What are there high numbers of in Immune-mediated Polyarthritis?
High numbers of neutrophils in synovial fluid
What is a synovial chondromatosis associated with?
In association with degenerative joint disease
What is a synovial cyst?
Periarticular synovium-lined structure filled with synovial fluid (decreased intra-articular pressure)
Where does synovial pad proliferation occur?
Fetlock joint of racing horses
What part of the spine is wobblers syndrome most likely to affect?
The neck
In dogs and horses
Where is bursitis in horses most likely to be found?
The neck, (cranial and nuchal)
