Skull & vertebrae

Question 1

What are the 3 different cranium types seen in dogs

Answer 1

Dolicocephalic - borzoi
Mesaticephalic - german shepherd
Brachycephalic - pug

Question 2

Features seen in brachycephalic patient

Answer 2

Domed, thin calvarium
Reduced or absent frontal sinuses
Shortened nasofacial area with crowded maxillary teeth
Small and thick-walled tympanic bullae
Fontanelles or cranium sutures may stay open

Question 3

What are the views that you position skull for xrays

Answer 3

Lateral
VD
Intraoral (VD/DV)
Oblique (temporomandibular joints, bullae)
Rostrocaudal
Open mouth for bullas
Closed mouth for frontal sinuses
Caudodorsal

Question 4

Which is more preferred in skull radiographs - vd or Dv

Answer 4

DV! Easier to achieve symmetry
- Put hard palate parallel to table

Question 5

TMJ view position

Answer 5

Patient on lateral recumbency, nose lifted to 10-30 degrees

Question 6

Which position would we want to take for seeing tympanic bullae

Answer 6

Rostrocaudal, open mouth

Question 7

Subperiostal hematoma features

Answer 7

egg-shell like new thin bone formation
From repeated less-serious trauma

Question 8

Periosteal reaction

Answer 8

Indicates new bone formation in reaction to the abnormal stimulants, such as tumor

Rapid irritative processes do not allow the periosteum time to lay down and consolidate new bone to form normal cortex. The cortex may appear lamellated, amorphous, or sunburst-like.

Question 9

Lytic changes

Answer 9

Lesions that replace normal bone or with a vast proportion showing a lower density or attenuation than the normal cancellous bone.

Question 10

Sclerosis

Answer 10

a focal, multifocal, or diffuse increase in the density of the bone matrix on radiographs or computed tomography (CT) imaging.

White part in radiographs, it tells you that there is irritation

Question 11

Craniomandibular osteopathy

Answer 11

Non-neoplastic proliferative bone disease
Marked new bone formation
Self-limiting
Grows outwards, not inwards (usually)
Most of changes disappear eventually

Question 12

Secondary hyperparathyroidism

Answer 12

Nutritional Ca deficiency
- affects mostly vertebrae, bones in limbs
BONE RESORPTION
- Floating teeth, rubber jaw
Teeth look abnormally white, as they retain their calcium content - but it disappears from bones in jaws
- lower jaw is first subject of demineralisation

Question 13

What should happen normally with C2 and C1 in cervical spine

Answer 13

Dorsal arch of C2 should overlap C1

Question 14

Butterfly anomaly

Answer 14

Abnormality of ossification centers
Vertebral bodies look like butterflies? Squeezed in the middle
Seen in VD/DV

Question 15

Hemivertebra

Answer 15

Failure of formation of a part of vertebral body
Missing part of the bone ventrally or dorsally
Wedge shape

Question 16

Block vertebra

Answer 16

Fusion of two vertebrae

Question 17

How to know if two vertebrae are truly fused or if the disc has slipped or gone

Answer 17

With the presence of sclerosis

Question 18

Transitional vertebrae

Answer 18

Vertebra showing features of those of adjacent vertebral segments (can be rudimentary)
- Problematic in lumbosacral area
Like additional rib in first lumbar vertebrae

Question 19

Spina bifida

Answer 19

Failure of fusion of dorsal part of lamina (including the spinous process

• Defective closure of vertebral column

Question 20

Opposite of lordosis

Answer 20

Kyphosis

Question 21

Atlantoaxial instability

Answer 21

Axial dens is absent, hypoplastic or fractured - or ligaments are absent or torn
Distance between C1 and C2 wider than usually

Question 22

Spondylosis

Answer 22

Bony “bridges” between vertebrae (osteophytes)
Degeneratiev

Question 23

Discospondylitis

Answer 23

Discs are affected

Although the disk itself cannot be seen on an X-ray, discospondylitis causes changes in the bony vertebrae adjacent to the affected disk

Makes half moon shadows between vertebral bodies

Question 24

Osteopetrosis

Answer 24

Group of a rare disorders that cause bones to grow abnormally and become overly dense.

Question 25

Hyperparathyroidism in spine

Answer 25

Decreased contrast between bone and soft tissue

Question 26

Degenerative disc disease

Answer 26

Hansen type 1
Degeneration of disc nucleus in relatively young age
Hansen type 2
Calcification of discs
Narrowing of intervertebral space