Kneeling 30 minutes daily linked to synovitis in knee OA
Kneeling for 30 minutes or longer daily is significantly associated with the prevalence of grade-1 or higher Hoffa-synovitis among a population of patients with or at risk for knee osteoarthritis, with the majority presenting with grade-1 synovitis or higher, according to data published in Arthritis Care & Research.
“Epidemiological data shows that the presence of synovitis markers, for example on MRI, can be a precursor of OA disease, as well as an important determinant of joint pain and structural decline in people with established OA,” Ans Van Ginckel, PT, PhD, of Ghent University, told Healio Rheumatology. “Nevertheless, it remains unclear which factors aggravate or facilitate synovitis development. Repetitive knee bending, and/or higher occupational loading, is a widely recognized, and modifiable, risk factor of OA development.”
Van Ginckel added: “Limited evidence suggests that people with OA who were more physically active and lean had a higher risk of Hoffa-synovitis on MRI than those who were not, indirectly suggesting a role for repetitive joint loading and the prevalence of synovitis. Yet, the relationship between frequent knee bending and synovitis prevalence in people with, or at risk of knee osteoarthritis, remains unclear.”
To analyze the links between knee bending and the prevalence of synovitis, as measured by noncontrast MRI, among patients with or at risk for OA, the researchers conducted a cross-sectional study of baseline data from the Foundation for the National Institutes of Health Biomarkers Consortium project. This project studied biomarkers of knee OA progression through 4 years using data from the Osteoarthritis Initiative. Van Ginckel and colleagues focused on 594 of the project’s participants with complete data on knee bending activities.
Data on knee bending activities were collected through a standard questionnaire, while Hoffa- and effusion-synovitis severity was determined by the MRI OsteoArthritis Knee Scoring system. The researchers used logistic regression, both unadjusted and adjusted for metabolic syndrome, physical activity level and sex.
According to the researchers, the prevalence of grade 1 or higher Hoffa-synovitis was 59%, with 62% presenting with effusion-synovitis. Adjusted for confounders, kneeling for 30 minutes or more in a single day was associated with the prevalence of grade 1 or higher Hoffa-synovitis prevalence (OR = 1.65; 95% CI, 1.11-2.47). Patients who kneeled for 30 minutes or more 1 day or less per week had a greater likelihood for prevalent Hoffa-synovitis than those who did not perform the activity (OR = 1.88; 95% CI, 1.11-3.18). The researchers found no additional significant associations. A sensitivity analyses yielded similar findings, they wrote.
“Of all activities, only prolonged deep kneeling for more than 30 minutes on a single day in the past month associated with greater odds of synovitis,” Van Ginckel said. “Considering the majority of the sample had mild synovitis on MRI, prolonged kneeling may be a risk factors of synovitis prevalence.” – by Jason Laday
Disclosure: Van Ginckel reports no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.