Fig. 1From: Inverted Rearfoot posture in subjects with coexisting patellofemoral osteoarthritis in medial knee osteoarthritis: an exploratory studyMeasurement of calcaneus inverted angle relative to the floor (θ). Calcaneus inverted angle relative to the floor was automatically calculated by the system according to the attached round black seal markers (a bottom of the calcaneal tuberosity; b enthesis of the Achilles tendon)Back to article page