A prosthesis for a through-knee amputee comprises a proximal limb portion 102 and a distal limb portion 106. The proximal limb portion 102 comprise a socket 104 which is configured to receive the upper leg of a through-knee amputee. The prosthesis also comprises at least two hinges 108 to connect the proximal limb portion 102 to the distal limb portion 106 so that they can rotate about a single axis of rotation 110. The prosthesis also comprises a contact member 112 and an engagement element 114. One of the contact member 112 and engagement element 114 is attached to the proximal limb portion 102 and the other of the contact member 112 and engagement element 114 is attached to the distal limb portion 106. One of both of the contact member 112 and engagement element 114 are biased towards the other. The contact member 112 is adapted so that when the proximal limb portion 102 and the distal limb portion 106 undergo extension from a position of flexion, the contact member 112 contacts the engagement element 114 to displace the engagement element 114 and/or contact member 112 against the bias.
