An exoskeleton structure comprising: - a pelvis assembly comprising a belt capable of surrounding the pelvis of a user to attach the pelvis assembly to the pelvis of the user, - a first lower limb assembly capable of being fastened to a first lower limb of the user, - a first pivot link connecting the first lower limb assembly to the pelvis assembly, the first pivot link allowing rotation of the first lower limb assembly relative to the pelvis assembly during an abduction or adduction movement of the first lower limb, - a first member capable of generating a first torque tending to oppose the rotation of the first lower limb assembly relative to the pelvis assembly during an adduction movement of the first lower limb, the first member comprising a first elastic return element between the first lower limb assembly and the pelvis assembly, the first elastic return element generating a return force tending to oppose the rotation of the first lower limb assembly relative to the pelvis assembly, - a first abutment capable of being fastened on the pelvis assembly so that in a first angular range of rotation of the first lower limb assembly, the first elastic return element abuts against the first abutment and exerts, via the first abutment, on the first lower limb assembly a return force tending to oppose the adduction movement of the lower limb, and in a second angular range, the first elastic return element is no longer in abutment against the first abutment and no longer exerts a return force on the lower limb assembly, - a second lower limb assembly capable of being fastened to a second lower limb of the user, - a second pivot link connecting the second lower limb assembly to the pelvis assembly, the second pivot link allowing rotation of the second lower limb assembly relative to the pelvis assembly during an abduction or adduction movement of the second lower limb, - a back assembly comprising a harness capable of being attached to the user's chest, - a spinal column mechanism linking the back assembly to the pelvis assembly, - a third pivot link connecting the spinal column mechanism to the pelvis assembly, the third pivot link allowing rotation of the pelvis assembly relative to the back assembly, during a relative movement of lateral inclination of the user's spine relative to the user's pelvis, - a third member capable of generating a third torque tending to oppose the rotation of the pelvis assembly relative to the back assembly during the relative movement of lateral inclination of the spine relative to the pelvis, and wherein the spinal column mechanism comprises a fourth pivot link allowing rotation of the back assembly relative to the pelvis assembly, during a twisting movement of the spine. - a pelvis assembly comprising a belt capable of surrounding the pelvis of a user to attach the pelvis assembly to the pelvis of the user, - a first lower limb assembly capable of being fastened to a first lower limb of the user, - a first pivot link connecting the first lower limb assembly to the pelvis assembly, the first pivot link allowing rotation of the first lower limb assembly relative to the pelvis assembly during an abduction or adduction movement of the first lower limb, - a first member capable of generating a first torque tending to oppose the rotation of the first lower limb assembly relative to the pelvis assembly during an adduction movement of the first lower limb, the first member comprising a first elastic return element between the first lower limb assembly and the pelvis assembly, the first elastic return element generating a return force tending to oppose the rotation of the first lower limb assembly relative to the pelvis assembly, - a first abutment capable of being fastened on the pelvis assembly so that in a first angular range of rotation of the first lower limb assembly, the first elastic return element abuts against the first abutment and exerts, via the first abutment, on the first lower limb assembly a return force tending to oppose the adduction movement of the lower limb, and in a second angular range, the first elastic return element is no longer in abutment against the first abutment and no longer exerts a return force on the lower limb assembly, - a second lower limb assembly capable of being fastened to a second lower limb of the user, - a second pivot link connecting the second lower limb assembly to the pelvis assembly, the second pivot link allowing rotation of the second lower limb assembly relative to the pelvis assembly during an abduction or adduction movement of the second lower limb, - a back assembly comprising a harness capable of being attached to the user's chest, - a spinal column mechanism linking the back assembly to the pelvis assembly, - a third pivot link connecting the spinal column mechanism to the pelvis assembly, the third pivot link allowing rotation of the pelvis assembly relative to the back assembly, during a relative movement of lateral inclination of the user's spine relative to the user's pelvis, - a third member capable of generating a third torque tending to oppose the rotation of the pelvis assembly relative to the back assembly during the relative movement of lateral inclination of the spine relative to the pelvis, and