A theoretical model for neutral compounds in the polar latitude lower thermosphere has been developed. The results are compared with a previous middle latitude model in order to study the special polar region effects. The main difference between both models is the inclusion of horizontal winds which are very large and cannot be ignored at high latitudes. Their effects are even more important than diffusion itself. Absolute values for the atomic oxygen concentration are considerably lower, in agreement with recent measurements, and the consequences on the green line airglow are examined. The vertical winds induced by horizontal motions are much more important than those induced by direct solar heat input, so that a very different pattern with respect to middle latitudes is obtained.