Presumed concurrent medial coronoid process fracture is a frequent radiographic finding in dogs and cats with humeral condylar fractures

OBJECTIVE

To report the prevalence of presumed concurrent medial coronoid process fractures in a series of cases of humeral condylar fractures and evaluate factors influencing the presence of a suspected fracture of the medial coronoid process.

ANIMALS

48 dogs and 7 cats, with a total of 57 humeral fractures.

METHODS

Medical records of dogs and cats diagnosed with a humeral condylar fracture with radiographs were reviewed between October 2013 and March 2022. Species, sex, neutered status, age, weight, and the nature of the trauma were noted. Radiographs were assessed for the configuration of humeral condylar fracture, the presence of a suspected fractured medial coronoid process (MCP), number of MCP fragments, nature of fracture, degree of radioulnar incongruity, soft tissue swelling, and elbow luxation/subluxation.

RESULTS

A presumed fracture of the MCP was seen in 26 of 57 cases. Comminution of the condylar fracture was the only parameter that had a positive effect on the presence of a possible fractured MCP. Body weight was significantly associated with size of the suspected fractured MCP. The presence of this fracture was not associated with the type of humeral condylar fracture. The size of the presumed fractured MCP fragment was positively correlated with body weight.

CLINICAL RELEVANCE

There was a high prevalence of presumed fractured MCPs in dogs with humeral condylar fractures (almost 50%) and even more so in animals with comminuted fractures. The consequences of suspected fractured MCP associated with humeral condylar fractures and whether dogs and cats would benefit from removal of the fragment remain unknown.

Therapeutic success in fragmented coronoid process disease and other canine medial elbow compartment pathology: a systematic review with meta-analyses

Introduction

The correct treatment of elbow dysplasia is controversial in modern small animal orthopedics. The aim of this study was to compile all relevant literature of the therapy of fragmented coronoid process and other hereditary disorders of the medial elbow compartment and to statistically evaluate the therapeutic results in three meta-analyses.

Methods

The basis for the systematic literature review was a comprehensive database search of Web of Science, PubMed and Medline. Studies on living patients with above mentioned degenerative joint disease were included in the initial literature search. The data from the final studies, selected according to the PRISMA guidelines, was subsequently extracted. Finally, the success of the different therapies was compared and analyzed by three meta-analyses: success rate, mean difference and standardized mean difference.

Results

Fourteen of 494 publications covered by the systematic literature search remained. Their overall truth was: In studies where surgery outcomes was determined by clinical examination and owner questionnaires, it was found that surgical intervention had a significant positive outcome in the presence of fragmented coronoid process and medial compartment disease. Surgical outcomes were also good in three cross-over studies that investigated treatment success using computerized gait analysis. In contrast, comparative studies between surgical and conservative management yielded controversial results. The meta-analysis found no significant difference between medical and surgical therapy.

Discussion

The positive results of studies investigating owner satisfaction and veterinary clinical examination of surgical therapy for medial compartment disease were confirmed by two meta-analyses. However, their study designs were susceptible to observer biases. A third meta-analysis of standardized mean difference differentiating computerized gait analysis results of surgical and conservative management found no evidence of significant superiority of each treatment modality. It however had a limited number of subjects. More comparative studies of high evidence are needed to better understand medial compartment disease and provide the clinician with more accurate diagnostics to separate pathology that should be treated surgically from pathology that can benefit from conservative therapy similarly. Given the invasiveness a more cautious approach might be warranted regarding generally recommending surgery for pathology of the medial elbow compartment.

Evaluation of a small-bore needle arthroscope for diagnosis and treatment of medial coronoid disease in dogs: a pilot study with short-term assessment

CASE HISTORY

Dogs (n = 15) that were presented to a single veterinary teaching hospital with elbow dysplasia-associated lameness between September 2021 and May 2022, and were determined to require arthroscopy based on imaging results, were prospectively recruited into the study. The median duration of lameness was 4 (min 1, max 24) months.

CLINICAL FINDINGS

Various breeds were represented with a median body weight of 31.6 (min 15, max 46.4) kg and median age at presentation of 14 (min 8, max 83) months. Results of imaging modalities (CT) were consistent with medial coronoid disease with fissured or fragmented medial coronoid process in all dogs.

ARTHROSCOPIC FINDINGS

Feasibility of the needle arthroscopy (NA) procedure was firstly assessed in a preliminary cadaveric study in forelimbs (n = 10) collected from 10 adult dogs euthanised for reasons unrelated to the study. Elbow exploration was performed through a medial approach beginning with NA (1.9 mm 0° angle scope) followed by standard arthroscopy (SA; 2.4 mm 30° angle scope). The quality and extent of visualisation (scored through the number of anatomical structures visualised) were recorded and statistically compared. As the cadaver study indicated that NA allowed safe inspection of all structures in medial/caudal compartments, this procedure was then used in the dogs requiring treatment. In the clinical setting, elbow exploration was successful in all dogs and the treatment (removal of osteochondral fragments) was performed without requiring conversion into SA. One month after surgery, all dogs had an improvement in their lameness score (0-5) and 12/15 dogs were no longer lame. There was a reduction in Canine Orthopaedic Index scores measured a median of 99 (min 47, max 180) days after surgery (24 (IQR 19.5-31.5)) compared to the pre-operative period (49 (IQR 46.5-57); p < 0.001).

CLINICAL RELEVANCE

Needle arthroscopy-assisted removal of osteochondral fragments was performed in all dogs with satisfactory short-term clinical outcome. NA is a feasible technique for diagnosis and lesion assessment in dogs with a fissured or fragmented coronoid process. Larger clinical studies with longer follow-up are necessary to validate the NanoScope operative arthroscopy system as an alternative strategy to SA for video-assisted treatment of medial coronoid disease.

Comparison of 18F-sodium fluoride positron emission tomography and CT: An exploratory study in 12 dogs with elbow pain

18F-Sodium Fluoride (18F-NaF) positron emission tomography (PET) provides high resolution functional information about bone activity and can be fused with CT images to improve three-dimensional localization and characterization of lesions. This prospective, observational study assessed 18F-NaF PET-CT for imaging of canine elbows, compared PET with CT findings, and assessed correlation with lameness. Twelve patients with elbow pain were included. Cases included primarily young, large breed dogs. A three-level clinical lameness score was assigned to each forelimb. All dogs had bilateral elbow joints imaged with CT and PET under general anesthesia, approximately 1.5 h after intravenous injection of 3 MBq/kg of 18F-NaF. Imaging findings were independently reviewed by two radiologists using a three-level scoring scheme over nine anatomical regions in the elbow. PET imaging identified areas of bone activity where minimal change was identified on CT. PET imaging also demonstrated absence of uptake in areas where modeling was present on CT. A stronger correlation was observed between clinical grades and PET scores (r2  = 0.38, P = .001) than between clinical grades and CT scores (r2  = 0.17, P = .048). The total PET scores were significantly different for each clinical grade (P = .013) but total CT scores did not differ (P = .139). This exploratory study suggests that PET improves the ability to detect lesions and to determine the clinical significance of CT findings in dogs with elbow pain.

Utility of MRI for Characterizing Articular Cartilage Pathology in Dogs with Medial Coronoid Process Disease

OBJECTIVE

To determine whether assessment of morphological MRI sequences or delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) would have strong correlations with arthroscopic assessment of cartilage pathology in dogs with naturally occurring medial compartment pathology of the elbow.

METHODS

Dogs tentatively diagnosed with medial coronoid disease had evaluation of their affected elbows using radiography, morphological MRI sequences, and dGEMRIC MRI evaluation prior to arthroscopy. Elbow radiographs were graded 0-6 for severity of changes. Cartilage of the medial coronoid process (MCP) and humeral trochlea (HT) were scored on a 0-3 scale using anatomical MRI sequences. The T1 relaxation times for the MCP and trochlea were quantified using dGEMRIC. Cartilage pathology was graded arthroscopically using a modified Outerbridge score (MOS) by a surgeon blinded to MRI assessment. Correlations between radiography and MOS, and between MRI and MOS, were quantified.

RESULTS

Twenty-six elbows in 14 dogs were evaluated. There were statistically significant (p < 0.05) moderate correlations between radiographic scores and MOS for the MCP (r = 0.71) and HT (0.57). There was a statistically significant moderate correlation between morphological MRI scoring and MOS for the HT (r = 0.54; p < 0.05), but not for the MCP (p > 0.05). There was a weak, but significant correlation, between the dGEMRIC value and MOS of the MCP (r = 0.41; p < 0.05), but no correlation between the dGEMRIC values and MOS for the HT (p > 0.05).

CLINICAL RELEVANCE

Statistically significant correlations to MOS were identified for both radiography and MRI but neither diagnostic modality provided sufficiently strong correlations to serve as a substitute for arthroscopic evaluation of the articular cartilage.

Computed tomography and radiographic assessment of congruity between the ulnar trochlear notch and humeral trochlea in large breed dogs

OBJECTIVE

Assess the fit between the ulnar trochlear notch (UTN) and humeral trochlea (HT) in elbow radiographs and computed tomography (CT) images by measuring the curvature radii in normal joints.

METHODS

Mediolateral extended view (MLE) and CT were performed on 16 elbows from cadaveric dogs weighing over 20 kg. Curves were traced at the subchondral level from the UTN central ridge and the HT sagittal groove related to the UTN on ~132° joint extension. Curvature radii were achieved using appropriate computer software.

RESULTS

Intraclass correlation coefficient between MLE/CT measurements were statistically significant, with lower limits of a 95% confidence interval (CI) >0.75. The mean differences between MLE/CT measurements were -0.71 mm (95% CI: -0.97 to -0.45) for UTN and -1.04 mm (95% CI: -1.21 to -0.87) for HT. The UTN and HT curvature radii typology were similar, with maximum radius values at the starting point and two intermediate peaks. The UTN curvature radii were bigger than the HT radii, with the largest differences in the most proximal aspect of the joint and in the second intermediate peak.

CLINICAL SIGNIFICANCE

To the authors' knowledge, this is the first report on humeroulnar congruity through curvature radii evaluation. The software and methodology proposed enabled an adequate UTN and HT radii curvature assessment in MLE and CT images. Comparative studies in normal and dysplastic dogs of various breeds could better clarify the role of UTN and HT curvature radii in elbow incongruity and dysplasia.