What does rearfoot posting do in gait mechanics?

• A. Alters position of subtalar joint or rearfoot from heel-strike to foot-flat; must be dynamic and control (not eliminate) STJ motion
• B. Eliminates subtalar joint motion
• C. Only affects forefoot
• D. No effect on subtalar joint

Answer: (A)

Rearfoot posting changes the way the hindfoot sits and moves as the foot first contacts the ground, so it can influence how the subtalar joint behaves from heel strike through foot-flat. The idea is to provide dynamic control of subtalar motion—reducing excessive eversion or inversion—while still allowing natural movement, not to lock the joint or eliminate motion entirely. By altering rearfoot alignment, posting helps guide the entire leg through a more stable and efficient progression during early stance, and it affects the rearfoot (not only the forefoot) in the process.