Some small errors in the full version of PainScience.com's article about patellofemoral pain syndrome:

• Argues that running is good for your joints using a correlational study stating that 9% of marathon runners have arthritis vs 18% of non-runners. (Obvious explanation: people with arthritis are less likely to run marathons.)
• Incorrect unit conversions in pressure: e.g. 4000 psi is ~280 kg-force / cm^2, not 715.