CT attenuation of the medial coronoid process is reduced in dogs with medial coronoid disease but independent of arthroscopic disease severity

Abstract

OBJECTIVE To compare the attenuation of the medial coronoid process (MCP) in dogs with and without arthroscopically confirmed evidence of medial coronoid disease (MCD). ANIMALS The database at our institution was searched for cases with thoracic limb lameness, diagnosed with MCD by arthroscopic examination that had CT as part of their investigation and compared with a control group of elbow joints from cadavers euthanized for reasons unrelated to MCD. A total of 84 elbow joints were included that met these criteria. PROCEDURES Following CT, a standardized measurement of the MCP was obtained from apex to base and the mean attenuation, SD, and total area were recorded. A comparative measurement was obtained from the proximal radial cortex at the level of the nutrient foramen. Elbow joint arthroscopy was carried out using standard portals, and the modified Outerbridge score was (MOS) used to score elbow joint cartilage. Descriptive and inferential statistics were carried out using MLwiN and R. RESULTS Attenuation of the MCP was reduced in dogs with MCD compared with those with no MCD (P < .002). No significant differences were observed in the attenuation between categories of severity (MOS). There was good inter- and intraobserver agreement between measurements (intraclass correlation coefficient = 0.89 and 0.95, respectively). CLINICAL RELEVANCE MCP attenuation is reduced in dogs with MCD compared with dogs with no evidence of MCD. This finding may be a useful tool for early detection of MCD, but there is no relationship with arthroscopic lesion severity.

Comparison of Hounsfield Units within the Humeral Trochlea and Medial Coronoid Process in a Population of Labrador X Golden Retriever Guide Dogs and Border Collies

“…Wennemuth and colleagues 21 measured the tip of the MCP and displayed decreased BMD in dogs with FMCP. Humphreys and colleagues 22 measured the apex of the MCP to the level of the The purpose of our publication was not to identify regions associated with disease, but develop an overall estimate of sclerosis of the MCP and humeral trochlea and compare if breed variations exist. The ROI were selected to provide a representation of the entire MCP and humeral trochlea and were consistent with contact regions of the canine elbow identified by Preston and colleagues 29 and Cuddy and colleagues 30 where a relative increase in sclerosis would be expected.…”

“…Wennemuth and colleagues 21 measured the tip of the MCP and displayed decreased BMD in dogs with FMCP. Humphreys and colleagues 22 measured the apex of the MCP to the level of the coronoid notch, and demonstrated decreased tissue attenuation in the MCP of dogs with MCPD. A recent publication by Gander Soares and colleagues 23 measured HU of the humeral condyle across 14 ROI and two image planes in a population of Labrador Retrievers, and revealed increased HU with apical fragmentation of the MCP, when compared with radial incisure fragmentation and those without MCPD.…”

“…Villamonte-Chevalier and colleagues 20 described the same findings with multiple regions of interest (ROI) of the ulna, radius and humerus in a sagittal and sagittal oblique plane. Phillips and colleagues, 19 Wennemuth and colleagues 21 and Humphreys and colleagues 22 found a significantly lower HU in the apex of the MCP in dogs with FMCP, measured in the transverse plane. Gander Soares and colleagues 23 demonstrated increased HU of the medial and lateral aspects of the humeral condyle in Labradors with apical FMCP, compared with dogs with radial incisure FMCP.…”

“…16 17 Consequently, assessment of HU and BMD calculations has been utilized for assessing a variety of regions across the MCP and comparing clinically normal dogs and those affected by MCPD. 18 19 20 21 22 Kunst and colleagues 18 discovered a significant increase in medullary BMD of the MCP in the transverse plane in dogs with FMCP compared with sound dogs. Villamonte-Chevalier and colleagues 20 described the same findings with multiple regions of interest (ROI) of the ulna, radius and humerus in a sagittal and sagittal oblique plane.…”

“…To date, the focus of studies investigating HU tissue attenuation or BMD has been to compare dogs with and without MCPD. 15,[18][19][20][21][22][23] A single study compared Labradors with and without MCPD to Greyhounds and noted consistently lower BMD in Greyhounds compared with both populations of Labradors. 19 A further study compared HU between a population of clinically normal and lame Labradors to numerous breeds, finding an increase in HU values in Labradors compared with Golden Retrievers.…”