System and method for delivery conformation and removal of intramedullary bone fixation devices

A system for stabilizing a fractured bone having an intramedullary canal, the system comprising:

• a thermo-chemically activated implant shaped to be inserted into an intramedullary canal of the bone, wherein the implant comprises a support structure and a thermo-chemically activated polymer matrix, a glass transition temperature of the thermo-chemically activated polymer matrix being greater than 37 degrees Celsius, a first thermo-chemical state above the glass transition temperature where the thermo-chemically activated polymer matrix is deformable, a second thermo-chemical state below the glass transition temperature where the thermo-chemically activated polymer matrix is relatively rigid, the thermo-chemically activated polymer being responsive to heating above the glass transition temperature to transform from the second thermo-chemical state to the first thermo-chemical state and responsive to cooling below the glass transition temperature to transform from the first thermo-chemical state to the second thermo-chemical state, the thermo-chemically activated polymer permitting multiple transitions between the first thermo-chemical state and the second thermo-chemical state, the polymer matrix, while the polymer is in the first thermo-chemical state, being responsive to a deforming force to expand from a first shape to a second shape which conforms to a form of a surrounding portion of the intramedullary canal, and the polymer matrix, while the polymer is in the second thermo-chemical state, maintaining the second shape in a relatively rigid configuration to provide torsional, axial, and bending reinforcement to the fractured bone sufficient to promote healing of the fractured bone, the support structure comprising a cage and at least one stiffening rod, the cage comprising a sleeve comprising a web-like stent portion, the polymer matrix being sufficiently deformable to conform to a bone at a first thermo-chemical state and sufficiently hardened to stabilize the bone at a second thermo-chemical state;
• and
• an implant deformer removably insertable into the thermo-chemically activated implant and configured to induce expansion of the thermo-chemically activated implant within the intramedullary canal so as to transform the implant between the first shape and the second shape within the intramedullary canal with a controlled transfer of thermal energy between the implant deformer and the polymer matrix;
• wherein the implant deformer is configured to transfer thermal energy to or receive thermal energy from the thermo-chemically activated implant to help control activation of the thermo-chemically activated implant.

A method for stabilizing a fractured bone having an intramedullary canal, the method comprising:

• inserting an implant into an intramedullary canal of the bone, wherein the implant comprises a support structure and a thermo-chemically activated polymer matrix, a glass transition temperature of the thermo-chemically activated polymer matrix being greater than 37 degrees Celsius, a first thermo-chemical state above the glass transition temperature where the thermo-chemically activated polymer matrix is deformable, a second thermo-chemical state below the glass transition temperature where the thermo-chemically activated polymer matrix is relatively rigid, the thermo-chemically activated polymer being responsive to heating above the glass transition temperature to transform from the second thermo-chemical state to the first thermo-chemical state and responsive to cooling below the glass transition temperature to transform from the first thermo-chemical state to the second thermo-chemical state, the thermo-chemically activated polymer permitting multiple transitions between the first thermo-chemical state and the second thermo-chemical state, the polymer matrix, while the polymer is in the first thermo-chemical state, being responsive to a deforming force to expand from a first shape to a second shape which conforms to a form of a surrounding portion of the intramedullary canal, and the polymer matrix, while the polymer is in the second thermo-chemical state, maintaining the second shape in a relatively rigid configuration to provide torsional, axial, and bending reinforcement to the fractured bone sufficient to promote healing of the fractured bone, the support structure comprising a cage and at least one stiffening rod, the cage comprising a sleeve comprising a web-like stent portion, the polymer matrix being sufficiently deformable to conform to a bone at a first thermo-chemical state and sufficiently hardened to stabilize the bone at a second thermo-chemical state;
• inserting an implant deformer into the implant;
• expanding the implant deformer to transform the implant from the first shape to the second shape;
• and
• removing the implant deformer from the intramedullary canal;
• wherein, after removal of the implant deformer from the intramedullary canal, the implant remains at the second shape.

A method for stabilizing a fractured bone having an intramedullary canal, comprising:

• inserting a thermo-chemically activated implant into an intramedullary canal of the bone, wherein the implant comprises a support structure and a thermo-chemically activated polymer matrix, a glass transition temperature of the thermo-chemically activated polymer implant being greater than 37 degrees Celsius, a first thermo-chemical state above the glass transition temperature where the thermo-chemically activated polymer implant is deformable, a second thermo-chemical state below the glass transition temperature where the thermo-chemically activated polymer implant is relatively rigid, the thermo-chemically activated polymer being responsive to heating above the glass transition temperature to transform from the second thermo-chemical state to the first thermo-chemical state and responsive to cooling below the glass transition temperature to transform from the first thermo-chemical state to the second thermo-chemical state, the thermo-chemically activated polymer permitting multiple transitions between the first thermo-chemical state and the second thermo-chemical state, the polymer matrix, while the polymer is in the first thermo-chemical state, being responsive to a deforming force to expand from a first shape to a second shape which conforms to a form of a surrounding portion of the intramedullary canal, and the polymer matrix, while the polymer is in the second thermo-chemical state, maintaining the second shape in a relatively rigid configuration to provide torsional, axial, and bending reinforcement to the fractured bone sufficient to promote healing of the fractured bone;
• expanding an implant deformer to induce expansion of the thermo-chemically activated implant within the intramedullary canal so as to transform the implant between the first shape and the second shape within the intramedullary canal;
• and
• transferring thermal energy between the implant deformer and the thermo-chemically activated implant to transform the thermo-chemically activated implant from a first thermo-chemical state to a second thermo-chemical state to increase rigidity of the thermo-chemically activated implant within the intramedullary canal, wherein the implant comprises a support structure and a thermo-chemically activated polymer implant, the support structure comprising a cage and at least one stiffening rod, the cage comprising a sleeve comprising a web-like stent portion, the polymer matrix being sufficiently deformable to conform to a bone at said first thermo-chemical state and sufficiently hardened to stabilize the bone at said second thermo-chemical state.