The effects of positioning, reason for screening and the referring veterinarian on prevalence estimates of canine hip dysplasia

Objective The main purpose of the study was to compare reliability of measurements for the evaluation of hip joint laxity in 59 dogs. Materials and Methods Measurement of the distraction index (DI) of the PennHIP method and the Norberg angle (NA) of the Fédération Cynologique Internationale (FCI) scoring scheme as well as scoring according to the FCI scheme and the Swiss scoring scheme were performed by three observers at different level of experience. For each dog, two radiographs were acquired with each method by the same operator to evaluate intraoperator-reliability. Results Intraoperator-reliability was slightly better for the NA compared with the DI with an intraclass correlation coefficient (ICC) of 0.962 and 0.892 respectively. The ICC showed excellent results in intraobserver-reliability and interobserver-reliability for both the NA (ICC 0.975; 0.969) and the DI (ICC 0.986; 0.972). Thus, the NA as well as the DI can be considered as reliable measurements. The FCI scheme and the Swiss scoring scheme provide similar reliability. While the FCI scheme seems to be slightly more reliable in experienced observers (Kappa FCI 0.687; Kappa Swiss 0.681), the Swiss scoring scheme had a noticeable better reliability for the unexperienced observer (Kappa FCI 0.465; Kappa Swiss 0.514). Clinical Significance The Swiss scoring scheme provides a structured guideline for the interpretation of hip radiographs and can thus be recommended to unexperienced observers.

Section: Discussioncontrasting

confidence: 96%

Comparison of Reliability of Norberg Angle and Distraction Index as Measurements for Hip Laxity in Dogs

Klever¹,

Brühschwein²,

Wagner³

et al. 2020

“…However, the French data may underestimate the prevalence since most dogs were younger at the moment of phenotyping. It has been proven statistically that the prevalence of CHD and CED increases with phenotyping at an older age (7,8). In the current study as well as another study, it was found for HHOC that, the older the dog, the more affected cases seem to be found (9).…”

Section: Discussionsupporting

confidence: 68%

Combined prevalence of inherited skeletal disorders in dog breeds in Belgium

Coopman¹,

Broeckx²,

Verelst³

et al. 2014

Self Cite

Canine hip dysplasia (CHD), canine elbow dysplasia (CED), and humeral head osteochondrosis (HHOC) are inherited traits with uneven incidence in dog breeds. Knowledge of the combined prevalence of these three disorders is necessary to estimate the effect of the currently applied breeding strategies, in order to improve the genetic health of the population. Official screening results of the Belgian National Committee for Inherited Skeletal Disorders (NCSID) revealed that an average of 31.8% (CHD, CED, or both; n = 1273 dogs) and 47.2% (CHD, CED, HHOC, or a combination of these three diseases; n = 250 dogs) of dogs are mildly to severely affected by at least one skeletal disorder. According to the current breeding recommendations in some dog breeds in Belgium, these animals should be restricted (mild signs) or excluded (moderate to severe signs) from breeding. The introduction of genetic parameters, such as estimated breeding values, might create a better approach to gradually reduce the incidence of these complex inherited joint disorders, without compromising genetic population health.

“…Regarding the standard ventrodorsal projection of the hips, it is well established that a correct positioning of the pelvis highly influences the assessment and classification of the patient between the different grades of dysplasia. [15][16][17] Nevertheless, there is no clear threshold to decide with confidence whether a radiograph should be accepted or rejected, and this decision is mostly based on a subjective assessment. [15][16][17] Similarly, there is no defined threshold to help deciding whether a laxity projection is acceptable or not, but the usual criteria of symmetry are used: the pelvis has to be straight with a symmetrical size and shape of the iliac wings and obturator foramina, and both femurs have to be in a similar position, with a close degree of superimposition with each ischium.…”

Section: Discussionmentioning

confidence: 99%

Technical Repeatability and Reproducibility of the Stress Radiographs Performed with the Vezzoni-Modified Badertscher Hip Distension Device

Bertal

Rycke

Vezzoni³

et al. 2019

Objective The aim of this study was to evaluate the repeatability and reproducibility of the radiographical stress technique using the Vezzoni-modified Badertscher distension device (VMBDD). Materials and Methods Stress radiographs of 10 dogs obtained with the VMBDD were performed consecutively by two different operators and then measured twice by a third veterinarian. The technical repeatability was first assessed individually for the two operators who took the stress radiographs, followed by the technical reproducibility. The obtained variances were used to calculate the 95% limits of agreement for the measurement repeatability, the technical repeatability and the technical reproducibility. Results Both the technical repeatability and reproducibility of the VMBDD technique were good, with the 95% limits of agreement of the measurement repeatability and technical repeatability equalling ± 0.07 overall, and the 95% limits of agreement of the technical reproducibility being ± 0.09. Clinical Significance These results, in combination with the previous results for the measurement of the laxity index, support the use of the VMBDD as a reliable in-house evaluation method to assess the hip joint by trained clinicians. For screening purposes, however, we suggest to limit the number of evaluators, to limit the variability.