The Prevalence of Patella Luxation in a Domestic Cat (Felis Silvestris Catus) Population in South Africa

Background: Patella luxation (PL) changes joint biomechanics leading to osteoarthritis. In the last two decades, few studies have been conducted on PL within a domestic cat population. There is a wide range of results with regard to PL prevalence, ranging from 0.1 to 58%. The objective of this cross-sectional descriptive study was to investigate the prevalence of PL in a nonpedigree domestic cat population within South Africa.

Materials and Methods: A total of 209 cats were recruited from shelters and private owners, of which 69 cats were eliminated. Prior to evaluation, a screening questionnaire was completed and the cats were weighed. The evaluation included palpation, passive range of motion and the patella laxity test. The Roush (1993) grading scale was used to grade the degree of laxity.

Results: A PL prevalence of 45.71% was found. The majority of cats had increased mediolateral movement (45.71%) or grade 1 PL (41.43%). Grades 2 and 3 luxations were noted in 2.41 and 0.71% of cats, respectively. Only 5.71% of cats had stable patellae. A significant association was identified between the environment and the presence of PL (p = 0.043; χ² = 4.1). There was a higher prevalence in females and in cats under 2.5 kg, although no significant correlation was found between these variables.

Conclusion: The high prevalence suggests that clinicians may need to adjust the significance placed on feline PL. Future studies should investigate PL prevalence in sedated cats and external factors that can affect PL expression. Additionally, a feline grading scale should be devised that considers their natural laxity.

Publication History

Article published online:
12 September 2025