Imaging - pathophysiology

Question 1

Carrer VS 2008

Elbows with IOHC and normal elbows compared with CT

Answer 1

IOHC = hypoattenuating defect with hyperattenuating margins

HUI seen, may be underlying factor

26% MCD

80% DJD

Question 2

Moores JSAP 2017

Observational study of 34 elbows with HIF

Answer 2

Fissure size not related to # risk (supported by Marcellin-L’s study - 40% incomplete fissure fractured, vs 8% complete fissure)

18% progressed to #, 24% required sx

Question 3

Mella VCOT 2022

Retrospective study CT feautres of sound Frenchies

Answer 3

No HIF seen (thus no increased risk for HCF), but 40% had intracondylar sclerotic band (Carrera)

22% MCD

28% DJD -> suggests subclinical disease exists

Moores VCOT 2021: sclerotic band a/w HIF in Springers, 44% MCD)

Question 4

Franklin VRU 2023

Prevalence of incidental HIF in brachys on CT

Answer 4

Frenchies 12%, Pugs 11% (cf Mella VCOT 2022 no HIF)

Question 5

Payne VCOT 2024

CT of HIFs in Springers to study pattern of propagation

Answer 5

HUI 13%

HIF starts caudal (60deg caudal to supratrochlear foramen) and extends cranial

Question 6

Etiology of HIF unclear

Answer 6

Farrell VS 2011: HIF developmental abnormality resulting from incomplete fusion of condyles (IOHC)

Butterworth JSAP 2011: BUT HIF develops in skeletally mature dogs with previously normal elbow - may be a form of stress fracture

Supporting Butterworth:
-Marcellin-Li VS 1994: fibrous osteoclastic env (not cartilaginous) similar to atrophic nonunion
-Moores VCNA 2021: fissures extended to supratrochlear foramen, beyond where cartilaginous plate extend to

Question 7

Davenport VRU 2023

CT evaluation of HIF and intracondylar sclerosis in contralateral limbs of Frenchies and Spaniels with HCF

Answer 7

Sclerosis seen at # sites in 60% of Frenchies and 95% of Spaniels

In contralateral elbows:
-Frenchies HIF 44% (potential predisposing factor to HCF), sclerosis 50%
—NO MCP, incongruity, DJD

-Spaniels HIF 60%, sclerosis 95%
—30% MCD, 4% incongruity, 20% DJD

Question 8

Strohmeier VR 2021

Case series 9 Frenchies with HCF

Answer 8

70% HIF in contralateral limb - potential predisposing factor to HCF
(50% Davenport VRU 2023)

44% (Oliva VCOT 2024)

Question 9

Schettler VCOT 2022

10y period in Kansas State uni HCFs in dogs

Answer 9

Frenchies 50x more likely to have HCFs > Cockers > Brittany

Question 10

Pierrot JAVMA 2024

48 dogs, 7 cats, with HCF
Rads reveiwed for prevalence of FMCP

Answer 10

FMCP in 46%

Comminution only factor a/w FMCP

BWT was a/w size of FMCP

Consequences of FMCP a/w HCF and removal of fragment unclear