The Biomechanics of Driving

Everyday I drive to school. The starting position when I am sitting in the driver's seat is such that my hips are flexed, my knees are slightly flexed, my left ankle is slightly plantar flexed to rest my foot on the floor, while my right ankle is slightly dorsiflexed to hover my foot over the gas pedal. To accelerate, I have to plantar flex my right ankle to push down on the pedal. Flexion at the hips and knees, as well as dorsiflexion and plantarflexion at the ankle, are all motions occurring in the sagittal plane around a frontal axis. The osteokinematics of the ankle joint are dorsiflexion to plantarflexion in an open kinematic chain because the proximal trunk is fixed in the seated position while the distal part, the foot, is moving. The arthrokinematics are that in plantarflexion the convex surface of the talus rolls posteriorly and glides anteriorly on the concave surfaces of the distal tibia and fibula. The prime movers for ankle plantarflexion are the gastrocnemius, soleus, and plantaris muscles which contract concentrically to produce this motion.