The association between running volume and knee osteoarthritis prevalence: A systematic review and meta-analysis

There is conflicting evidence regarding whether regular running is associated with knee osteoarthritis prevalence. Previous evidence reports lower knee osteoarthritis prevalence in recreational runners compared with professionals (with a higher training volume) and controls (who have a lower training volume). The aim of this systematic review and meta-analysis was to determine if weekly running volume is associated with knee osteoarthritis prevalence. Four databases (PubMed, Web of Science, Scopus and SPORTDiscus) were searched from earliest record to November 2021. Included studies must i) recruit participants who ran regularly and recorded weekly running volume; ii) include a control group (running <8 km per week); iii) record knee osteoarthritis prevalence (either by radiological imaging or self-reported diagnosis from a doctor or physiotherapist). Study bias was assessed using the Newcastle-Ottawa Scale (NOS). Pooled effects were estimated using a random effects model. Odds ratios with 95% prediction and confidence intervals are reported. Nine observational case control studies with a total of 12,273 participants (1272 runners) were included in the meta-analysis. Most of the included studies were rated as having a very high (n = 2) or high (n = 3) risk of bias on the Newcastle Ottawa Scale. There was no difference in knee osteoarthritis prevalence between runners and controls (OR = 0.97, 95% CI = 0.56 to 1.68). Runners undertaking 8-32.1 km (OR = 1.17, 95% CI = 0.77 to 1.80), 32.2-48 km (OR = 1.04, 95% CI = 0.48 to 2.31) or > 48 km per week (OR = 0.62, 95% CI = 0.35 to 1.10) did not exhibit higher knee osteoarthritis prevalence compared with controls. It is unclear whether running volume is associated with increased knee osteoarthritis prevalence, future large-scale, high quality prospective studies are required.