The invention relates to a shoulder mechanism for an orthosis comprising in succession:a first element (1) that is stationary relative to the usera second element (2) that is hinged to the first element about a first hinge axis (A1)a third element (3) that is hinged to the second element about a second hinge axis (A2) andan upper arm (4) that is hinged to the third element about a third hinge axis (A3).According to the invention, the hinge axes (A1, A2, A3) extend in directions that define a frame of reference that is non-orthogonal.
