A joint for a rehabilitation device (64, 80, 90, 100), the joint being defined for operation between an end of a first member (12, 82, 92, 102) and an end of a second member (14, 84, 94, 104), the joint being further defined to enable the second member (14, 84, 94, 104) to pivot at the joint with respect to the first member (12, 82, 92, 102), the joint comprising: a positioning mechanism for defining a set position from which the second member (14, 84, 94, 104) pivots, with respect to the first member (12, 82, 92, 102), the positioning mechanism comprising an intermediate component for location between the ends of the first (12, 82, 92, 102) and second members (14, 84, 94, 104), and a clamping mechanism for urging the ends of the first (12, 82, 92, 102) and second members (14, 84, 94, 104) together to secure the intermediate component therebetween to define the joint in use, the intermediate component being configured, when the clamping mechanism defines the joint, to engage with the end of the first member (12, 82, 92, 102) when the second member (14, 84, 94, 104) is pivoted from the set position, the intermediate component being further configured to interact with the second member (14, 84, 94, 104) at the set position when it is pivoted back to the set position relative to the intermediate component to prevent further pivoting beyond the set position; a restriction mechanism for restricting the degree of pivoting of the second member (14, 84, 94, 104), from the set position, with respect to the first member; and a biasing mechanism for biasing the second member (14, 84, 94, 104) such that it returns to the set position when an opposing force applied to the second member (14, 84, 94, 104) is less than the bias of the mechanism, wherein, when the clamping mechanism is released, the intermediate component is able to be disengaged from the first member (12, 82, 92, 102) and then rotated, together with a pivoting of the second member (14, 84, 94, 104) with respect to the first member (12, 82, 92, 102), to define a different set position when the clamping mechanism is reclamped, and, when the joint is in the set position, the biasing mechanism is configured such that no bias is applied to the second member (14, 84, 94, 104); characterised by a gearing mechanism connecting to the biasing mechanism such that adjustment of the gearing mechanism by rotation of the gearing mechanism in a first direction increases bias in the biasing mechanism, and adjustment of the gearing mechanism by rotation of the gearing mechanism in a second direction decreases bias in the biasing mechanism; wherein the biasing mechanism includes a spring having a first end engaging the gearing mechanism and a second end engaging the second member (14, 84, 94, 104), the spring passing through an aperture defined by the positioning mechanism. a positioning mechanism for defining a set position from which the second member (14, 84, 94, 104) pivots, with respect to the first member (12, 82, 92, 102), the positioning mechanism comprising an intermediate component for location between the ends of the first (12, 82, 92, 102) and second members (14, 84, 94, 104), and a clamping mechanism for urging the ends of the first (12, 82, 92, 102) and second members (14, 84, 94, 104) together to secure the intermediate component therebetween to define the joint in use, the intermediate component being configured, when the clamping mechanism defines the joint, to engage with the end of the first member (12, 82, 92, 102) when the second member (14, 84, 94, 104) is pivoted from the set position, the intermediate component being further configured to interact with the second member (14, 84, 94, 104) at the set position when it is pivoted back to the set position relative to the intermediate component to prevent further pivoting beyond the set position; a restriction mechanism for restricting the degree of pivoting of the second member (14, 84, 94, 104), from the set position, with respect to the first member; and a biasing mechanism for biasing the second member (14, 84, 94, 104) such that it returns to the set position when an opposing force applied to the second member (14, 84, 94, 104) is less than the bias of the mechanism, wherein, when the clamping mechanism is released, the intermediate component is able to be disengaged from the first member (12, 82, 92, 102) and then rotated, together with a pivoting of the second member (14, 84, 94, 104) with respect to the first member (12, 82, 92, 102), to define a different set position when the clamping mechanism is reclamped, and, when the joint is in the set position, the biasing mechanism is configured such that no bias is applied to the second member (14, 84, 94, 104); characterised by a gearing mechanism connecting to the biasing mechanism such that adjustment of the gearing mechanism by rotation of the gearing mechanism in a first direction increases bias in the biasing mechanism, and adjustment of the gearing mechanism by rotation of the gearing mechanism in a second direction decreases bias in the biasing mechanism; wherein the biasing mechanism includes a spring having a first end engaging the gearing mechanism and a second end engaging the second member (14, 84, 94, 104), the spring passing through an aperture defined by the positioning mechanism.