Ch 8 - Juvenile Flashcards
How does neutering affect physeal closure times in cats?
It causes delays; Castrated males have delayed physeal closure times when compared to entire males.
Castrated females in one study had delayed closure of the distal radial physis.
What is the primary source of vitamin D in dogs and cats?
diet
What is the most common clinical outcome of physeal disruption?
angular limb deformity, due to partial or complete premature closure of the growth plate
All physes contribute to bone growth equally - T or F?
False; certain physes contribute more, e.g. distal ulnar physis contributes 85% of total ulnar growth potential.
The distal ulnar physis contributes ___% of the growth potential of the ulna.
85
Why is the distal ulnar physis the most commonly affected location for premature closure i.e. injury, in dogs, but not in cats?
It is largely due to the conical shape of the physis in dogs, which is not the case in cats.
Describe the main findings and the cause.
Premature closure of the distal ulnar physis
Which of the following is NOT a radiographic feature of premature closure of the distal ulnar physis?
a) Shortened ulna relative to the radius
b) Carpal varus deformity
c) Craniomedial subluxation of the distal radius
d) Proximal displacement of the styloid process of the ulna
b) Carpal varus deformity
Explanation: The typical deformity observed is carpal valgus, not carpal varus.
Which of the following is a typical radiographic feature of premature closure of the distal ulnar physis?
a) Shortened radius relative to the ulna
b) Cranial bowing of the radius
c) Proximal displacement of the accessory carpal bone relative to the styloid process of the ulna
d) Narrowed humeroulnar joint space
b) Cranial bowing of the radius
What is the common result of premature closure of the distal ulnar physis in relation to the radial cortex?
a) Caudal bowing of the radius
b) Cortical thickening of the cranial radial cortex
c) Cortical thickening of the caudal radial cortex
d) Lateral displacement of the radial cortex
c) Cortical thickening of the caudal radial cortex
Which of the following is true regarding the anconeal process in cases of premature closure of the distal ulnar physis?
a) It may undergo accelerated fusion
b) It may fail to fuse, but it is difficult to determine if this is related to the physis injury
c) It never fails to fuse and is unrelated to the injury
d) It causes lateral subluxation of the radius
b) It may fail to fuse, but it is difficult to determine if this is related to the physis injury
In premature closure of the distal ulnar physis, which of the following is displaced proximally?
a) Accessory carpal bone
b) Trochlear notch of the ulna
c) Styloid process of the ulna
d) Distal radius
c) Styloid process of the ulna
Which of the following is associated with radial deformities seen in premature closure of the distal ulnar physis?
a) Distal radial subluxation
b) Medial bowing of the radius
c) Cortical thickening of the cranial radial cortex
d) Craniomedial subluxation of the distal radius
d) Craniomedial subluxation of the distal radius
Which part of the radius is most commonly affected by premature physeal closure?
a) Proximal radial physis
b) Distal radial physis
c) Mid-shaft of the radius
d) Both proximal and distal physes equally
Answer: b) Distal radial physis
What percentage of longitudinal growth of the radius is contributed by the distal radial physis?
a) 50%
b) 70%
c) 30%
d) 90%
b) 70%
Which of the following is NOT a typical radiographic feature of symmetrical premature closure of the distal radial physis?
a) Shortening of the radius relative to the ulna
b) Widened humeroradial joint space
c) Angular limb deformity with carpal valgus
d) Widened humeroulnar joint space
c) Angular limb deformity with carpal valgus
What clinical outcome is commonly associated with symmetrical premature closure of the distal radial physis in canines?
a) Carpal varus with inward rotation of the manus
b) Carpal valgus with outward rotation of the manus
c) Carpal varus with outward rotation of the manus
d) Angular limb deformity with no rotation
a) Carpal varus with inward rotation of the manus
Which species is more likely to experience carpal joint incongruity due to premature closure of the distal radial physis?
a) Canine patients
b) Feline patients
c) Both species equally
d) Neither, it’s not species-specific
b) Feline patients
Which of the following is a key radiographic feature of asymmetrical premature closure of the distal radial physis?
a) Widened humeroradial joint space
b) Sloping of the distal radial articular surface
c) Shortening of the ulna relative to the radius
d) Proximal subluxation of the radial head
b) Sloping of the distal radial articular surface
What is a common angular limb deformity resulting from asymmetrical premature closure of the distal radial physis?
a) Carpal valgus
b) Carpal varus
c) Either varus or valgus, depending on the site of closure
d) No angular deformity occurs
c) Either varus or valgus, depending on the site of closure
Premature closure of which part of the radial physis typically results in more severe clinical signs?
a) Proximal radial physis
b) Distal radial physis
c) Both result in equally severe signs
d) Proximal ulna
Answer: b) Distal radial physis
Explanation: The distal radial physis contributes 70% of radial growth, making its premature closure more severe than the proximal radial physis.
What is the most notable radiographic feature of premature closure of both the distal ulnar and radial physes?
a) Elbow joint degeneration
b) Shortening of the radius and ulna, more severe in the ulna
c) Shortening of the radius but normal ulna length
d) Lengthening of the ulna
b) Shortening of the radius and ulna, more severe in the ulna
Which of the following is NOT a radiographic feature of simultaneous ulnar and radial physeal disturbances?
a) Shortening of the length of the radius and ulna
b) Lateral bowing of the diaphyses
c) Secondary changes in the elbow joint
d) Angulation of the radiocarpal joint
c) Secondary changes in the elbow joint
Premature closure of both the distal ulnar and radial physes (together) is associated with:
a) Carpal varus
b) Carpal valgus
b) Carpal valgus