  Spatial dependence of the magnetic field and the superconducting current in a
flux line pinned by a screw dislocation are computed. Interaction of a
superconducting vortex with the chiral-symmetry breaking elastic strain of a
screw dislocation results in a helical current along the axis of the
dislocation. It is argued that screw dislocations make impossible a force-free
arrangement of flux lines in the presence of a transport current.
