Nerve fiber = multicellular, containing both an axon and surrounding myelin sheath. The axon comes from a single neuron, but the myelin sheath is made by a train of many myelinating Schwann cells. In the case of unmyelinated axons, the unmyelinated fiber shares each Schwann cell with several other unmyelinated axons.
Flat feet (pes planus) occur when a child has no arch in their foot. Because an arch does not form, the foot appears to turn to the outside. Children with out-toeing due to flatfeet will rarely experience pain symptoms will not require treatment.
What causes hammer, claw, and mallet toes? Tight shoes are the most common cause of these toe problems. Wearing tight shoes can cause the toe muscles to get out of balance. If a shoe forces a toe to stay in a bent position for too long, the muscles tighten and the tendons shorten, or contract.