The bending of an arm or leg is called flexion.
bending, twisting,tilting, arm swings, leg swings
A limb is a term used for an arm or leg.
When you straighten your arm or leg (as in a pushing movement), you EXTEND the arm or leg. When you bend your arm at the elbow or your leg at the knee, you FLEX the arm at the elbow and flex the leg at the knee.
your leg
your leg
leg
arm - aim - aid - lid - led - leg
Flexion is the medical term meaning bending
Arm, (Arm rest) Leg, (Leg rest)
The Esperanto words for arm and leg are brako and kruro.
Please immobilize that patient's arm/leg/whatever.