The natural history of humeral intracondylar fissure: an observational study of 30 dogs

OBJECTIVES: To determine the risk of condylar fracture, or of needing to have a transcondylar screw placed, and to identify risk factors in a cohort of dogs with humeral intracondylar fissure (also known as incomplete ossification of the humeral condyle) that was initially managed non-surgically.

METHODS: A retrospective owner survey of dogs diagnosed with humeral intracondylar fissure as an incidental finding and managed non-surgically with a minimum of two years follow-up. Body weight, age, estimated fissure size, gender and contralateral fracture at the time of diagnosis were evaluated as potential risk factors for the development of a humeral condylar fracture or for having a transcondylar screw placed.

RESULTS: Data were available for 30 dogs (34 elbows). Six humeral condyles with a mean fissure size of 50% fractured at a mean of 14 months after diagnosis. A transcondylar screw was placed across two humeral condyles with fissure sizes of 60 and 100% at 11 and 17 months. No risk factors were identified for fracture/screw placement. For those cases that did not fracture or have a screw placed mean fissure size was 52% and mean follow-up time was 56 months (range 29 to 79 months).

CLINICAL SIGNIFICANCE: Eighteen percent of cases progressed to fracture and 24% in total required surgery. This information allows clinicians and owners to make an informed decision regarding surgery when faced with a dog with humeral intracondylar fissure identified as an incidental finding.