Force, displacement, and rate controlled shaped memory material implants

Abstract

A force, displacement, and rate controlled shape memory material implant. The rate of implant shape change as well as the force exerted on the surrounding tissue of the implant can be controlled by the surgeon and the extent of movement is controlled in circumstances where the bone element is free to move. The invention allows for the first time the fine control of force when fixating osteoporotic bone and rate of bone transport when working near the spinal cord. This heating profile of the implant provides the surgeon to control the extent of microstructure phase transformation so that the rate, force or extent of tissue movement can be controlled individually or together.

1 - 8 . (canceled) 
     
     
         9 . An implant comprising a memory material having a shape changing transition temperature range that is designed to be controlled with an energy delivery device that creates heat in the implant causing a controlled change in shape to create a shape changing force to change shape of the implant to a shape change position, wherein
 (a) the memory material comprises martensitic phase memory material,   (b) the martensitic phase memory material is operable to transition to austenitic phase memory material in the shape changing transition temperature range,   (c) the implant is operable to transition at least some of the martensitic phase memory material to the austenitic phase memory material in a plurality of pre-selected increments to create a corresponding plurality of incremental shape changing forces to change the shape of the implant to a corresponding plurality of incremental shape change positions, and   (d) the corresponding plurality of incremental shape change positions are positions of the implant that successively further change the shape of the implant.   
     
     
         10 . The implant of  claim 9 , wherein the implant is selected from the group consisting of catheters, intrauterine contraceptive devices, gastrointestinal compression clip, blood vessel filter, coronary artery stent, skin staple, bone staple, and bone plate. 
     
     
         11 . The implant of  claim 9 , wherein the implant comprises a plurality of members, wherein the plurality of members are operable to be controlled together by the energy delivery device. 
     
     
         12 . The implant of  claim 9 , wherein the implant comprises a plurality of members, wherein the plurality of members are operable to be controlled independently by the energy delivery device. 
     
     
         13 . The implant of  claim 9 , wherein the memory material has martensitic to austenitic finish transition temperatures sufficiently different so that the plurality of incremental shape change positions can be implemented so as to achieve high resolution control of a characteristic selected from the group consisting of an implant force, rate of shape change, extent of shape change. 
     
     
         14 . The implant of  claim 9 , where the change in the shape of the implant is opening or closing of the implant. 
     
     
         15 . The implant of  claim 9 , wherein the plurality of the pre-selected increments are pre-selected to control a pre-selected characteristic selected from the group consisting of (a) a corresponding plurality of incremental shape change forces, (b) a corresponding plurality of periods of time of incremental rate of shape change of the implant, (c) a corresponding plurality of extents of shape change of the implant, and (d) combinations thereof. 
     
     
         16 . The implant of  claim 15 , wherein the pre-selected characteristic comprises a combination of (a) the corresponding plurality of the incremental shape change forces, (b) the corresponding plurality of the periods of time of the incremental rate of shape change of the implant, and (c) the corresponding plurality of the extents of shape change of the implant. 
     
     
         17 . The implant of  claim 15 , wherein the pre-selected characteristic comprises the corresponding plurality of the incremental shape change forces. 
     
     
         18 . The implant of  claim 17 , wherein the corresponding plurality of the incremental shape change forces are incrementally between 10% and 20% increments of force. 
     
     
         19 . The implant of  claim 17 , wherein the corresponding plurality of the incremental shape change forces are 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, and 100% of force. 
     
     
         20 . The implant of  claim 17 , wherein the pre-selected characteristic further comprises the corresponding plurality of the periods of time of the incremental rate of shape change of the implant. 
     
     
         21 . The implant of  claim 17 , wherein the pre-selected characteristic further comprises the corresponding plurality of the extents of shape change of the implant. 
     
     
         22 . The implant of  claim 15 , wherein the pre-selected characteristic comprises the corresponding plurality of the periods of time of the incremental rate of shape change of the implant. 
     
     
         23 . The implant of  claim 22 , wherein the corresponding plurality of the periods of time of the incremental rate of shape change of the implant are incrementally one second increments. 
     
     
         24 . The implant of  claim 22 , wherein the pre-selected characteristic further comprises the corresponding plurality of the extents of shape change of the implant. 
     
     
         25 . The implant of  claim 15 , wherein the pre-selected characteristic comprises the corresponding plurality of the extents of shape change of the implant. 
     
     
         26 . The implant of  claim 25 , wherein the corresponding plurality of the extents of shape change of the implants are incrementally between 10% and 20% increments. 
     
     
         27 . The implant of  claim 25 , wherein the corresponding plurality of the extents of shape change of the implant are 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, and 100%. 
     
     
         28 . The implant of  claim 9 , wherein the implant is operable to be being controlled with the energy delivery device using a feedback control loop. 
     
     
         29 . The implant of  claim 28 , wherein the feedback control loop measures temperature of the implant.