Edge spin transport in the disordered two-dimensional topological insulator <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi>WTe</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:math>

The spin conductance of two-dimensional topological insulators (2D TIs) is not expected to be quantized in the presence perturbations that break spin-rotational symmetry. However, deviation from pristine-limit quantization has yet studied detail. In this paper, we define current operator for helical edge modes a 2D TI and introduce four-terminal setup measure conductances. Using developed formalism, consider effects disorder terms symmetry or give rise edge-to-edge coupling. We identify key role played by torque an out-of-equilibrium edge. then utilize tight-binding model monolayer ${\mathrm{WTe}}_{2}$ scattering matrix formalism numerically study transport device. particular, calculate conductances characteristic decay length magnetic disorder. addition, interedge quantum point contact geometry. find Hall surprisingly robust symmetry-breaking perturbations, as long time-reversal preserved weak.