It is a matter of common experience that disorder will tend to increase if things are left to themselves.

The disorder tends to be unilateral and monoostotic, with only one limb typically involved.

Thus disorder will tend to increase with time if the system obeys an initial condition of high order.

This disorder tends to have three main stages.

The disorder tends to appear gradually, with the first symptoms most likely to occur between childhood and middle age.

The disorder tends to become worse with the cold weather.

"This disorder does tend to burn out, for some reason," says Cross.

The disorder can affect anyone but tends to occur most often in middle aged women.

This disorder most commonly affects children and tends to be more actively spread during the summer.

The exact cause is not clear, although the disorder tends to run in families, so a genetic factor is likely.