DI Final- Bone Flashcards
Approximately how many days does it take for osteoid formation to mineralize?
12-15
What are the ends of a bone called?
Proximal and distal epiphyses
Which part of the bone contains marrow?
Medullary cavity
What law says that bone will respond to the stresses or strains placed (or not placed) on it?
Wolff’s Law
What do you call it when there is an radioulnar length mismatch?
(Joint) Incongruity
Hypertrophic osteodystrophy seems to be associated with this virus and infection with this bacterium.
Distemper virus
E.coli
Adolescent dogs of which breeds are susceptible to Legg-Calve-Perthes? What does it cause?
Toy and small breed dogs
Aseptic necrosis of the femoral head due to compromised blood supply
What are the most common causes of aggressive bone lesions?
Neoplasia
Infections
T/F: Osteoarthritis can cause cortex loss.
False
___ ____ is the growth center for the epiphysis, ____ is the growth center for the diaphysis.
Articular cartilage
Physis (or epiphyseal plate)
What is the secondary center for bone formation called that provides a point for muscle attachment?
Apophysis
What is the most common primary bone tumor?
Osteosarcoma
OSA is usually monostotic and metaphyseal. It is often located toward the ____ and away from the ____, except the distal _____.
Stifle
Elbow
Tibia
What 2 types of tumors can cause nail bed lesions?
Squamous cell carcinomas
Malignant melanoma
Which Salter Harris fracture is most common?
Type II
What are the 3 areas that are assessed to determine whether a bone lesion is aggressive or not?
Cortex (for destruction)
Periosteum (for a reaction, active or inactive)
Transition zone (whether it is distinct or indistinct)
Which cells responsible for remodeling and growth of the bone cortex, are also responsible for osteogenesis during fracture repair?
Osteoprogenitor cells
Which type of ossification occurs in flat bones?
Intramembrenous
T/F: Developmental lesions are frequently bilateral.
True.
What do you call a piece of necrotic cartilage that breaks free? They can attach to the synovium and become vascularized.
Joint mice (fragments)
How many views are needed to assess the cortex?
2
______ lysis is characterized by coalescing regions of ill-defined bone destruction.
Permeative.
What disorder results from the failure of endochondral ossification?
Osteochondrosis
T/F: Incongruity is very difficult to diagnose radiographically, CT and arthroscopy are much more accurate.
True
T/F: A bone lesion showing cortex destruction but no other signs of aggression is probably not aggressive.
False, only 1 sign of aggression is needed to deem a lesion aggressive.
What are 4 rule-outs for a metaphyseal monostotic aggressive lesion?
Primary bone tumor (OSA)
Mycotic osteomyelitis (rarely monostotic)
Bacterial osteomyelitis (rarely metaphyseal)
Metastatic cancer (rarely metaphyseal and monostotic)
What do you call a fracture that occurs secondary to an event that would not normally lead to a fracture?
Pathologic fracture
In a dog, what is a major predilection site for OCD?
Caudal humeral head
T/F: Most dogs with UAP have other lesions.
True (e.g. DJD, incongruency…)
Fragmenting of this process is very common, especially in medium and large breed dogs. CT is needed to diagnose this and signs can be seen as early as 4-6 months. What is it?
Medial coronoid process (FCP)
T/F: Lysis and sclerosis in a lesion can aid in determining aggression of a bone lesion.
False
A _____ is the dislocation of an anatomic part. A _____ is a partial dislocation.
Luxation
Subluxation
What type of view may you need to take to demonstrate the full extent of the instability of a dislocation?
Stress views
What disorder is characterized by an ununited anconeal process and fragmented medial coronoid process on the ulna, as well as osteochondrosis of the humeral condyle?
Elbow dysplasia
Flattening or concavity of subchondral bone with adjacent sclerosis are radiographic signs of what condition? What does the addition of a mineralized flap indicate?
Osteochondrosis
OCD
What is the main radiographic sign with a fractured medial coronoid process?
New bone formation on the proximal aspect of the anconeal process.
What is the self-limiting disease of large breed dogs characterized by shifting leg lameness? The lesion often begins at the nutrient foramen and causes increased medullary opacity.
Panosteitis
What developmental systemic disease of rapidly growing dogs that begins in the metaphysis of tubular bones, causes a “double physis”-sign and can lead to growth anomalies? There is a breed disposition, but only Weimaraner litters will have the whole litter affected.
Hypertrophic osteodystrophy
What part of the leg in a young dog is commonly misinterpreted as avulsed?
Tibial crest
In what view is a flexor enthesopathy in the canine elbow not visible?
Caudocranial
T/F: Radiographic aggressiveness predicts biologic aggressiveness.
False
T/F: No radiographic aggressiveness usually means no biologic aggressiveness
True
Which types of tumors tend to metastasize to bones?
Prostate
Mammary
Bladder
Primary bone tumors can be lytic, blastic or mixed. What do the terms lytic and blastic mean?
Lytic = destructive, radiolucent
Blastic = productive, radioopaque
What can you do to get a good rad of the toes that minimizes superimposition?
Put gauze between the toes
What technique can you consider using in a trauma patient to get more views but reduce pain?
Horizontal beam
What are 3 things often confused with fractures?
Nutrient foramen
Normal physes
Sesamoid bones
T/F: The Salter Harris system of classifying fractures applies only to skeletally mature patients.
False, immature
Describe a type I Salter Harris fracture.
“S”
Straight across
Slipped
(A fracture along the growth plate/physis)
Describe a type II Salter Harris fracture.
“A”
Above
(A fracture along the physis and up through the metaphysis)
Describe a type III Salter Harris fracture.
“L”
Lower
beLow
(A fracture along the physis and down through the epiphysis)
Describe a type IV Salter Harris fracture.
"T" Through Transverse Two (A fracture through the growth plate, metaphysis and epiphysis)
Describe a type V Salter Harris fracture.
“ER”
Erasure of physis
Crush
(A fracture that doesn’t displace the growth plate but damages it directly through compression)
A fulcrum-assisted hyperextension, traction, weight-bearing, axial-rotation and wedge are some methods by which _____ radiographs may be obtained.
stress
T/F: Deep sedation or anesthesia is required for proper spinal radiographs.
True
Which type of Salter Harris fracture has a high chance of secondary growth anomaly?
Type V
What do you do to compensate for beam-divergence when radiographing the whole spine?
Take multiple exposures
What is the most common cause of spinal pain/neuropathy you will see in your practice?
Disc disease
With secondary bone healing, early callus formation occurs in ____ days, the fracture line disappears and callus bridging occurs at ____days. After ____ months cortex and medullary cavity are re-established and the fracture line is gone.
10-20
30
3
T/F: Degenerate discs are subject to herniation.
True
Which breeds are susceptible to Hansen’s type 1 disc herniation? Is this acute or chronic?
Chondrodystrophic breeds
Acute
Material in the vertebral canal can only be seen radiographically if it is ______.
Mineralized
Which type of healing requires rigid fixation, direct bone contact and is uncommon in animals?
Primary
The most common transitional anomaly occurring at the thoracolumbar junction involves asymmetric development of the ___th rib. There are multiple variations to this anomaly, but the most clinically significant one is having a ____ rib on T13.
13
unilateral
T/F: Mineralization usually occurred prior to disc herniation in Hansen’s type I disc disease?
True
In secondary fracture healing, what stabilizes the fracture so ossification can occur?
Callus (fibrocartilage) formation
Which factors influence fracture healing?
Vascular integrity Location Extent Apposition Motion
Perfusion (increases/decreases?) as soft tissue injury (increases/decreases?)
Perfusion decreases as soft tissue injury increases
T/F: A tear in the cranial cruciate ligament can be diagnosed using radiographs.
False
Why does Hansen’s type I rarely occur between T2-T9? Where is it most common?
Intercapital ligament
At the T-L junction
Stenosis, abscesses and hemorrhage are associated with a(n) _____ lesion location, while edema and myelitis is associated with a(n)_____ lesion location. Tumors can be found in both aforementioned locations as well as _________, especially nerve root tumors.
Extradural
Intramedullary
Intradural-extramedullary
The golf-tee sign is associated with a __________ lesion
Intradural-extramedullary,caused by a lesion in the subarachnoid space.
What modality is most sensitive for detecting disc herniation?
MRI
What is a missile disc?
An Acute Non-compressive Nucleus Pulpsus Extrusion (ANNPE)
Acute herniation of a hydrated nucleus, acute neuropathy, spinal cord swelling & “bruising”
_____ ______ (location & bone) fractures in toy breeds heal slowly and have a high complication rate.
Distal antebrachium
Poor soft tissue environment, including poor blood supply, at the fracture site prevented the formation of a _____.
Callus
What is it called when bone heals in an abnormal position?
Malunion
German Shepherds are predisposed to ___-___ disc herniation.
T2-T5
What has a high signal in T2 MRI?
Water and fat
What is it called when annular protrusion caused by shifting of the central nuclear material results in spinal compression?
Type II Disc disease
Where is spondylosis clinically important?
L7-S1
Chronic instability, spondylosis, disc protrusion and stenosis of the vertebral canal at L7-S1 is known as:
Cauda Equina Syndrome
What is it called when all fracture healing has stopped and fragments have not united?
Non-union
Irregular _______ ______ is a key finding when diagnosing osteomyelitis complicating the healing of a fracture.
Periosteal reaction
What 3 things (alone or in combo) can occur when the ulna stops growing, trapping the radius between the below and carpus?
- Radius pushes on humerus as it continues to elongate, causing a HUMEROULNAR SUBLUXATION.
- BOWING of the radius occurs, without luxation.
- The radius pushes downward, causing the paw to be pushed laterally, resulting in VALGUS.
If the deformity caused by insufficient ulnar growth is severe, this device can be used to straighten the bone over time.
Ilizarov ring fixator
Type II disc disease is commonly associated with ____ degeneration.
Fibroid
T/F: Radiography is a good way of diagnosing type I or type II disc disease
False, can be done for screening but findings are non-specific
T/F: Radial closure is more common that ulnar closure and causes varus of the manus.
False, ulnar is more common. However it can cause varus of the manus.
T/F: Radial closure is more common that ulnar closure and causes varus of the manus.
False, ulnar is more common. However it can cause varus of the manus.
What very common cause of lameness is due to cartilage thinning leading to joint instability?
DJD/OA
T/F: In the PennHIP system, distraction and force have a linear relationship.
False, distraction is independent of force over a wide range of forces.
What is the most common clinical sign associated with Cauda Equine Syndrome?
Pain
What does one call an infection of the disc with adjacent vertebral osteomyelitis leading to a destruction of bone at the end plates adjacent to that disc?
Discospondylitis
In a normal hip, roughly ____% of the femoral head is covered by the dorsal rim in the acetabulum.
50
Articular cartilage transitions to bone to increase stability. What is this osseus metaplasia of articular cartilage called?
Osteophyte formation
T/F: Joint narrowing is not seen with DJD.
True
What changes can be seen on an x-ray signaling joint effusion?
Displacement of infrapatellar fat pad and the caudal facial stripe
Periosteal new bone formation at a tendon, ligament or joint capsule attachment due to pulling is called a ________
Traction osteophyte or Enthesophyte
T/F: OD at the shoulder and tarsus are common causes of OA.
True
T/F: Wear and tear does not cause OA.
False, this is a common cause of OA in the tarsus and carpus.
Which immune-mediated condition that occurs in the distal joints of small breed dogs involved the formation of subchondral cysts?
Erosive arthropathy
What species get meniscal ossicles? What are they?
Cats
Small mineralized opacities in the stifle joint
What species get meniscal ossicles? What are they?
Cats
Small mineralized opacities in the stifle joint
Which polygenic inherited condition that does not present phenotypically at birth eventually causes OA?
Hip dysplasia
What characteristic shape is a hip joint space when it is dysplastic?
Crescent
What is the earliest radiographic sign of canine hip dysplasia?
Joint laxity
What is the hallmark radiographic sign of discospondylitis?
End plate lysis
T/F: Discospondylitis is usually caused by bacteria.
True (Staph or Brucella)
What are osteophytes that form along the insertion of the joint capsule in hip dysplasia called?
Morgan lines
How many categories does the OFA system have? What is the earliest a dog can be certified hip dysplasia free?
7
24 months
In the PennHIP method, a _____ between the thighs allows lateral force application to the hip.
Fulcrum
When can a dog be certified hip dysplasia free with the PennHIP method? What is the number that depends on the position of the femoral head in distraction and compression views called?
4 months
Distraction Index
What can a dog be certified hip dysplasia free with the PennHIP method? What is the number that depends on the position of the femoral head in distraction and compression views called?
4 months
Distraction Index
A DI > ___ is associated with significant incidence of DJD.
0.3
Tip- Zero point three and DJD rhyme
What will make both the OFA and the PennHIPP systems obsolete?
Genetic testing
