Interest in feline orthopedic diseases has increased in recent years, highlighting the need for standardized radiographic criteria for diagnosing hip dysplasia in cats, similar to those used in dogs. This prospective study investigated associations between morphometric parameters and radiographic hip scores in 56 client-owned cats. Standard ventrodorsal pelvic radiographs were obtained, and the Norberg angle (NA) and femoral inclination angle (FIA) were measured bilaterally. Hips were scored using an adapted BVA/KC hip score scheme, with NA analyzed separately and secondary changes categorized. Group differences were analyzed with t-tests/ANOVA or Mann-Whitney U/Kruskal-Wallis as appropriate (Bonferroni where applicable); associations used Spearman"s ρ; predictors were modeled with multiple linear regression. In non-lame cats, NA values were 91.46±6.80° (right) and 92.55±6.90° (left), while FIA values were 121.71±5.57° (right) and 124.83±5.81° (left). Lame cats had significantly lower NA and higher FIA than non-lame cats, along with higher primary change and total scores. NA correlated negatively with primary and secondary change scores, secondary change categories (SCcat), and total scores, whereas FIA correlated positively. Across SCcat, NA decreased and primary change scores increased with severity. Younger cats showed higher NA values, while sex and fertility status had secondary effects. In multivariable models, NA was a negative predictor and FIA a positive predictor of total scores bilaterally. These results demonstrate that decreased NA and increased FIA are strongly associated with radiographic osteoarthritic changes, underscoring the role of hip geometry in the pathogenesis of feline hip dysplasia and osteoarthritis.
Ozturan et al. (Thu,) studied this question.