Implants, surgical tools for expanding implants and for orthopaedic surgery

A method of orthopaedic surgery of a bone, such as a vertebra, of a human or non-human mammal with an expandable intra-osseous implant, the method comprising:

• positioning the implant in the bone, the implant comprising:
• a support structure defining a longitudinal axis;
• a first set of movable parts movably mounted to the support structure and in an unexpanded state of the implant circumferentially spaced around the longitudinal axis from each other;
• a second set of movable parts movably mounted to the support structure and circumferentially spaced around the longitudinal axis from each other in the unexpanded state, which second set of movable parts is offset in a longitudinal direction of the implant from the first set of movable parts;
• each movable part in the first set of movable parts and the second set of movable parts being movable relative to the support structure in a radial direction away from the longitudinal axis from a first position in the unexpanded state to a second position in an expanded state of the implant, and each movable part comprising a load resisting surface for resisting a load external to the implant;
• a transmission for actuating movement of each movable part of the first and second sets of movable parts along a predetermined path from the first position to the second position, wherein in the expanded state said movable parts are supported against the external load to maintain the respective movable part in its second position;
• and
• the method further comprising expanding the implant, the expanding comprising the transmission actuating said movement for at least one movable part of at least one set of movable parts.

A surgical tool for expanding an expandable intra-osseous implant, the implant comprising a support structure defining a longitudinal axis;

• a first set of movable parts movably mounted to the support structure and in an unexpanded state of the implant circumferentially spaced around the longitudinal axis from each other;
• a second set of movable parts movably mounted to the support structure and circumferentially spaced around the longitudinal axis from each other in the unexpanded state, which second set of movable parts is offset in a longitudinal direction of the implant from the first set of movable parts;
• each movable part in the first set of movable parts and the second set of movable parts being movable relative to the support structure in a radial direction away from the longitudinal axis from a first position in the unexpanded state to a second position in an expanded state of the implant, and each movable part comprising a load resisting surface for resisting a load external to the implant;
• a transmission for actuating movement of each movable part of the first and second sets of movable parts along a predetermined path from the first position to the second position, wherein in the expanded state said movable parts are supported against the external load to maintain the respective movable part in its second position;
• the surgical tool comprising:
• a driver engageable with the transmission of the implant to selectively move at least one movable part along the predetermined path.