Riddle et al. 2003, Risk factors for plantar fasciitis

Matched case-control study (Journal of Bone and Joint Surgery, American Volume, 85(5):872-877) of risk factors for plantar fasciitis. Three independent associations: reduced ankle dorsiflexion (the strongest; odds ratio 23.3 for ≤0° versus >10°), obesity (BMI >30 kg/m², odds ratio 5.6 versus ≤25) and spending the majority of the workday on the feet (odds ratio 3.6). Reduced ankle dorsiflexion was the most important factor. Moderate (case-control design, so association not causation; later work finds the dorsiflexion link less consistent).