Incomplete ossification of the humeral condyle in spaniels

Area of Science:

• Veterinary Orthopedics
• Canine Genetics
• Biomechanical Research

Background:

• Humeral condylar fractures (HCFs) are a common orthopedic issue in dogs.
• Cocker spaniels exhibit a higher incidence of HCFs compared to other breeds.
• Male Cocker spaniels face an elevated risk for these fractures.

Purpose of the Study:

• To investigate the underlying causes of HCFs in Cocker spaniels.
• To explore the potential association between breed predisposition and HCFs.
• To identify possible genetic factors contributing to HCFs.

Main Methods:

• Retrospective analysis of 157 dogs with humeral fractures.
• Detailed examination of 18 dogs with HCFs, including radiography, CT, biopsy, and genetic evaluation.
• Radiographic assessment of contralateral humeral condyles in affected dogs.

Main Results:

• Cocker spaniels showed a significantly higher prevalence of HCFs and bilateral HCFs.
• Non-fractured humeral condyles in affected dogs displayed radiolucent lines, degenerative joint disease, and abnormal medial coronoid processes.
• Biopsies revealed fibrous tissue at fracture sites, and genetic analysis indicated a potential recessive inheritance pattern in affected Cocker spaniels.

Conclusions:

• Incomplete ossification of the humeral condyle is strongly associated with HCFs in Cocker spaniels and Brittany spaniels.
• A genetic predisposition, possibly with a recessive mode of inheritance, is suggested for this condition.
• Further research into the genetic basis of humeral condyle ossification is warranted.