Apparatus and methods for treatment of a bone

Abstract

Apparatus and methods for treatment of a bone. The apparatus may include an implant. The implant may include an implant tail and an implant head configured to expand, inside the bone, from a collapsed state to an expanded state. The apparatus may include an intramedullary rod defining a central longitudinal rod axis. The intramedullary rod may include a guide segment configured to guide the implant head into the bone and support the implant tail. The intramedullary rod may include an elongated extension member spaced radially apart from the central longitudinal axis. The extension member may be configured to provide clearance for the implant head as the implant head is advanced, in the collapsed state, into the bone. The extension member may be configured to provide clearance for the implant head in the expanded state.

1 . Apparatus for repairing a bone, the apparatus comprising:
 an implant comprising:   an implant tail; and   an implant head configured to expand, inside the bone, from a collapsed state into an expanded state; and   an intramedullary rod defining a central longitudinal rod axis and an outer surface, the rod comprising:
 a guide segment configured to:
 guide the implant head into the bone; and 
 support the implant tail; and 
 
 an elongated extension member spaced radially apart from the central longitudinal rod axis and configured to provide clearance with respect to the outer surface of the rod for:
 the implant head as the implant head is advanced, in the collapsed state, through the guide segment into the bone; and 
 the implant head in the expanded state. 
 
   
     
     
         2 . The apparatus of  claim 1 , the rod further comprising a ring-shaped segment that bridges between the guide segment and the elongated extension member;
 wherein the central longitudinal rod axis passes through an aperture of the ring-shaped segment.   
     
     
         3 . The apparatus of  claim 1  wherein:
 the rod defines a cylindrical volume; and 
 the guide segment is defined by a conical-shaped volume subtracted from the cylindrical volume. 
 
     
     
         4 . The apparatus of  claim 2  wherein a diameter of a base of the conical-shaped volume has a diameter that is less than a diameter of the cylindrical volume. 
     
     
         5 . The apparatus of  claim 1  wherein:
 the implant tail comprises a first anchor-receiving feature; and 
 the guide segment comprises:
 a guide surface defining a central longitudinal guide axis; and 
 a second anchor-receiving feature that defines a central longitudinal anchor axis substantially perpendicular to the central longitudinal guide axis; 
 
 wherein, in operation, the implant tail is supported by the guide surface such that the first anchor-receiving feature and the second anchor-receiving feature are aligned to receive the same anchor. 
 
     
     
         6 . The apparatus of  claim 1  wherein the rod comprises an outer surface that defines a cylindrical surface. 
     
     
         7 . The apparatus of  claim 1  wherein the rod comprises an outer surface that defines a conical surface. 
     
     
         8 . The apparatus of  claim 1  wherein the rod comprises:
 a first body segment that extends along a first length of the central longitudinal rod axis, the first body segment defining a uniform diameter along the first length; and 
 a second body segment, that extends along a second length of the central longitudinal rod axis, the second body segment defining a diameter that varies along the second length. 
 
     
     
         9 . The apparatus of  claim 1 , the guide segment comprising:
 an inner radius;   an outer radius; and   a guide surface defined by a thickness between the inner and outer radii.   
     
     
         10 . The apparatus of  claim 9  wherein the guide surface is defined by a cylindrical surface that intersects the guide segment. 
     
     
         11 . The apparatus of  claim 10  wherein the cylindrical surface is an oblique, cylindrical surface. 
     
     
         12 . The apparatus of  claim 10  wherein the cylindrical surface has a diameter greater than a maximum diameter defined by the guide segment. 
     
     
         13 . The apparatus of  claim 10  wherein the cylindrical surface has a diameter smaller than a maximum diameter defined by the guide segment. 
     
     
         14 . The apparatus of  claim 1  wherein a length of the guide segment is cannulated along the central longitudinal rod axis. 
     
     
         15 . The apparatus of  claim 1  wherein a length of the rod is cannulated along the central longitudinal rod axis. 
     
     
         16 . The apparatus of  claim 14  wherein the length is threaded. 
     
     
         17 . The apparatus of  claim 14  wherein the length is a first cannulated length, the rod comprising a second cannulated length that is spaced apart from the first length, along the central longitudinal rod axis, by a third length. 
     
     
         18 . The apparatus of  claim 17  wherein the elongated extension member extends along the third length. 
     
     
         19 . The apparatus of  claim 17  wherein the second cannulated length is threaded. 
     
     
         20 . The apparatus of  claim 5  wherein the central longitudinal rod axis intersects the central longitudinal guide axis at an angle less than 90 degrees;
 wherein the angle faces away from the elongated extension member. 
 
     
     
         21 . The apparatus of  claim 20  wherein the angle is between 45 and 15 degrees. 
     
     
         22 . The apparatus of  claim 6  wherein:
 the cylindrical surface is a first cylindrical surface; 
 the implant, in the collapsed state, defines a second cylindrical surface; and 
 a diameter of the second cylindrical surface is smaller than a diameter of the first cylindrical surface. 
 
     
     
         23 . The apparatus of  claim 1  wherein:
 the guide segment defines a cylindrical surface; and 
 the elongated extension member comprises the cylindrical surface. 
 
     
     
         24 . The apparatus of  claim 23  wherein the elongated extension member comprises an outer arc length that is less than a maximum circumference of the cylindrical surface. 
     
     
         25 . The apparatus of  claim 24  wherein the arc length is less than half of the maximum circumference. 
     
     
         26 . The apparatus of  claim 23  wherein the elongated extension member comprises a thickness that is less than a radius of the cylindrical surface. 
     
     
         27 . The apparatus of  claim 23  wherein the elongated extension member defines:
 a length along the central longitudinal rod axis; and 
 an outer surface area that is less than an outer surface area of the length of the guide segment along the central longitudinal axis. 
 
     
     
         28 . The apparatus of  claim 1 , the elongated extension member comprising a first mating feature configured to mate with a second mating feature;
 wherein mating of the first and second mating features is configured to transfer a force to the rod along the central longitudinal rod axis without deforming the rod.   
     
     
         29 . The apparatus of  claim 28  wherein, in operation, the force transferred to the rod is sufficient to drive the rod into the bone. 
     
     
         30 . The apparatus of  claim 29  comprising a tapered segment that, in operation, is configured to displace tissue inside the bone. 
     
     
         31 . The apparatus of  claim 28  wherein the first mating feature defines a depression. 
     
     
         32 . The apparatus of  claim 28  wherein the first mating feature comprises:
 a first depression; and 
 a second depression spaced apart from the first depression along the central longitudinal rod axis. 
 
     
     
         33 . The apparatus of  claim 28  wherein the first mating feature comprises:
 a depression; and 
 an edge of the elongated extension member. 
 
     
     
         34 . The apparatus of  claim 32  wherein:
 the elongated extension member comprises an anchor-receiving feature; and 
 the first depression is spaced apart from the second depression by a diameter of the anchor-receiving feature. 
 
     
     
         35 . The apparatus of  claim 34  wherein the anchor-receiving feature is threaded. 
     
     
         36 . The apparatus of  claim 34  wherein the first mating feature defines an aperture in the elongated extension member. 
     
     
         37 . The apparatus of  claim 28  wherein the first mating feature comprises a protrusion that extends from an outer surface of the rod. 
     
     
         38 . The apparatus of  claim 28 , the rod comprising a third mating feature that is configured to mate with a tool positioned outside the rod. 
     
     
         39 . The apparatus of  claim 1  wherein:
 the guide segment defines a longitudinal guide axis that is oblique to the central longitudinal rod axis; and 
 the elongated extension member defines a longitudinal extension axis that is substantially parallel to the central longitudinal rod axis. 
 
     
     
         40 . The apparatus of  claim 1  wherein the rod comprises a plurality of anchor-receiving features. 
     
     
         41 . The apparatus of  claim 40  wherein the plurality of anchor-receiving features comprises:
 a first anchor-receiving feature that defines a first longitudinal axis oblique to the central longitudinal rod axis; and 
 a second anchor-receiving feature that defines a second longitudinal axis oblique to the central longitudinal rod axis. 
 
     
     
         42 . The apparatus of  claim 41  wherein:
 the first longitudinal axis is positioned in a first plane that is substantially perpendicular to the central longitudinal rod axis; 
 the second longitudinal axis is positioned in a second plane that is:
 substantially parallel to the first plane; and 
 substantially perpendicular to the central longitudinal rod axis. 
 
 
     
     
         43 . The apparatus of  claim 42  wherein the first longitudinal axis intersects the second longitudinal axis. 
     
     
         44 . The apparatus of  claim 42 , the plurality of anchor-receiving features comprising a third anchor-receiving feature that defines a third longitudinal axis that is:
 oblique to the central longitudinal rod axis; and   transverse to the first and second planes.   
     
     
         45 . A method for repairing a fracture in a bone, the method comprising:
 positioning a first rod substantially perpendicular to a longitudinal axis of a second rod;   locking the first rod to the second rod;   inserting the first rod into an intramedullary cavity of the bone;   securing targeting tools to the second rod; and   using the targeting tools, securing the first rod to the bone.   
     
     
         46 . The method of  claim 45  further comprising using one or more apertures in the targeting tools, positioning an anchor in an anchor-receiving feature of the first rod. 
     
     
         47 . The method of  claim 46 , the positioning comprising mating a first mating feature of the first rod with a second mating feature of the second rod. 
     
     
         48 . The method of  claim 46 , the locking comprising driving an anchor, guided by a cannulated segment of the second rod, into a threaded anchor-receiving feature of the first rod. 
     
     
         49 . The method of  claim 45  further comprising:
 positioning a joint linking the first rod to the second rod inside the bone; and 
 affixing the targeting tools to the second rod outside the bone. 
 
     
     
         50 . The method of  claim 45  further comprising, using the targeting tools, guiding a drill into the bone. 
     
     
         51 . The method of  claim 50  further comprising, using a guide surface of the first rod, guiding the drill into the bone. 
     
     
         52 . The method of  claim 45  further comprising, using the targeting tools, guiding a reamer into the bone. 
     
     
         53 . The method of  claim 52  further comprising, using a guide surface of the first rod, guiding the reamer into the bone. 
     
     
         54 . The method of  claim 45  wherein the anchor-receiving feature is obscured by an outside surface of the bone. 
     
     
         55 . The method of  claim 45  further comprising:
 positioning an expandable implant inside the bone; 
 expanding the implant inside the bone; and 
 using the targeting tools, securing the expandable implant to the bone. 
 
     
     
         56 . The method of  claim 55  further comprising, using a guide surface of the first rod, positioning the implant inside the bone. 
     
     
         57 . The method of  claim 55  further comprising securing the implant to the first rod. 
     
     
         58 . The method of  claim 57  wherein the bone is a humerus, the method further comprising securing the implant to the bone such that a central longitudinal axis of the implant is positioned, relative to a central longitudinal axis of the rod, at an angle that conforms to an angle of inclination of the humerus. 
     
     
         59 . The method of  claim 58  further comprising expanding the implant within a head region of the humerus. 
     
     
         60 . The method of  claim 57  wherein the bone is a femur, the method further comprising securing the implant to the bone such that a central longitudinal axis of the implant is positioned, relative to a central longitudinal axis of the rod, at an angle that conforms to an angle of inclination of the femur. 
     
     
         61 . The method of  claim 60  further comprising expanding the implant within a head region of the femur. 
     
     
         62 . The method of  claim 45  further comprising affixing a third rod to the first rod such that a central longitudinal axis of the first rod is substantially parallel to a central longitudinal axis of the third rod. 
     
     
         63 . The method of  claim 62  further comprising securing the targeting tools to the third rod. 
     
     
         64 . The method of  claim 45  further comprising removing the second rod and the targeting tools after the first rod is secured to the bone. 
     
     
         65 . The method of  claim 55  further comprising removing the second rod and the targeting tools after the first rod and the implant are secured to the bone. 
     
     
         66 . The method of  claim 45  further comprising inserting the first rod into the bone though an articular surface-region of the bone. 
     
     
         67 . The method of  claim 45  further comprising, using a guide surface of the first rod, inserting an implant into the bone through an access hole in cortical bone. 
     
     
         68 . The method of  claim 45 , the securing comprising:
 aligning a cut-out in the targeting tools with a rib that protrudes from an outer surface of the second rod; and   positioning a set screw of the targeting tools into a cut out in the rib.   
     
     
         69 . The method of  claim 45  the inserting comprising applying a force to the second rod. 
     
     
         70 . The method of  claim 69  wherein the second rod is locked to the first rod such that the force drives the first rod into the bone without deforming the first rod. 
     
     
         71 . The method of  claim 45 , the inserting comprising driving the first rod into a femur along a femoral-shaft axis of the femur. 
     
     
         72 . The method of  claim 45 , the inserting comprising driving the first rod into a humerus along a longitudinal axis defined by the humerus. 
     
     
         73 . Apparatus for placement in an interior of a bone, the apparatus comprising an elongated member configured to be coupled to an implant including an implant tail, the elongated member comprising:
 a sleeve having a sleeve longitudinal axis;   an anchoring base fixed to, and extending away from, the sleeve; and   a threaded member fixed to the anchoring base and extending along the sleeve longitudinal axis and spaced radially apart from the sleeve to define an annular space for receiving the implant tail.   
     
     
         74 . The elongated member of  claim 73  wherein the sleeve defines, transverse to the longitudinal axis, a constant outside diameter. 
     
     
         75 . The elongated member of  claim 73  wherein the sleeve defines, transverse to the longitudinal axis, an outside diameter that varies along a length of the sleeve. 
     
     
         76 . The elongated member of  claim 73  wherein:
 the sleeve defines a first outside diameter transverse to the longitudinal axis; and 
 the anchoring base defines a second outside diameter, equal to the first outside diameter, transverse to the longitudinal axis. 
 
     
     
         77 . The elongated member of  claim 73  wherein the anchoring base includes a hollow mesh structure defining a plurality of openings. 
     
     
         78 . The elongated member of  claim 77  wherein:
 the anchoring base defines a base longitudinal axis; and 
 the mesh structure extends circumferentially about the longitudinal axis. 
 
     
     
         79 . The elongated member of  claim 77  wherein the mesh structure has:
 a first outside diameter transverse to a mesh longitudinal axis along a first portion of a length of the mesh structure; and 
 a second outside diameter, different from the first outside diameter, transverse to a mesh longitudinal axis along a second portion of the length of the mesh structure. 
 
     
     
         80 . The elongated member of  claim 77  wherein the mesh structure includes a plurality of struts and the plurality of openings are defined by the struts. 
     
     
         81 . The elongated member of  claim 77  wherein:
 the anchoring base includes a first end; 
 a second end, opposite the first end; 
 the hollow mesh structure is disposed between the first end and the second end; 
 the sleeve extends away from the first end; and 
 the second end is tapered. 
 
     
     
         82 . The elongated member of  claim 73  wherein the anchoring base defines a hole. 
     
     
         83 . The elongated member of  claim 82  wherein:
 the hole is a first hole; and 
 the anchoring base defines a second hole, the second hole being spaced apart from the first hole along a longitudinal axis of the anchoring base. 
 
     
     
         84 . The elongated member of  claim 82  wherein:
 the hole is a first hole; 
 the anchoring base defines a plurality of holes, the plurality of holes including the first hole; and 
 each hole is spaced apart from an adjacent hole along a longitudinal axis of the anchoring base. 
 
     
     
         85 . The elongated member of  claim 82  wherein a cross-section of the hole, transverse to a central axis of the hole, is circular. 
     
     
         86 . The elongated member of  claim 82  wherein the hole has a first diameter parallel to an anchoring base longitudinal axis and a second diameter extending circumferentially about the anchoring base longitudinal axis, wherein the first length is at least double the second length. 
     
     
         87 . The elongated member of  claim 82  wherein:
 the hole is a first hole; and 
 the anchoring base defines a second hole extending through the anchoring base, the second hole spaced circumferentially apart, about an anchoring base longitudinal axis, from the first hole. 
 
     
     
         88 . The elongated member of  claim 87  wherein a central axis extending through the first hole transects a central axis extending through the second hole. 
     
     
         89 . The elongated member of  claim 73  wherein the anchoring base includes:
 a first end; 
 a second end opposite the first end; and 
 a plurality of longitudinal struts, each strut coupled to, and extending between, the first and second end and spaced apart from an adjacent strut circumferentially about an anchoring base longitudinal axis. 
 
     
     
         90 . The apparatus of  claim 73  further comprising the implant, the implant including an implant head, an implant tail including an inner threaded portion and an implant base positioned between the head and the tail, wherein:
 the implant tail is sized to be seated in the annular space; and 
 the inner threaded portion is threaded to mate with the threaded member. 
 
     
     
         91 . The apparatus of  claim 73  wherein:
 an inner face of the sleeve has a circumference; and 
 an outer face of the implant tail has the circumference. 
 
     
     
         92 . The apparatus of  claim 90  wherein, in operation, the implant is coupled to the elongated member, the implant tail is seated in the annular space and the threaded member engages the inner threaded portion. 
     
     
         93 . The apparatus of  claim 90  wherein:
 the implant tail is cylindrical; and 
 in operation, the implant is coupled to the elongated member and the implant fills the annular space. 
 
     
     
         94 . The apparatus of  claim 90  wherein:
 the implant tail has a face oblique to an implant tail longitudinal axis; and 
 in operation, the implant is coupled to the elongated member and the implant fills a portion of the annular space. 
 
     
     
         95 . The apparatus of  claim 90  wherein:
 the implant tail defines a first hole and a second hole opposite the first hole across an implant tail longitudinal axis; 
 the sleeve defines a third hole and a fourth hole across the sleeve longitudinal axis; and 
 in operation, the implant is coupled to the elongated member and the first, second, third, and fourth hole are coaxial. 
 
     
     
         96 . Apparatus for placement in an interior of a bone, the apparatus comprising:
 a first intramedullary rod defining a screw hole having a central axis;   a second intramedullary rod configured to be coupled to the first rod, the second intramedullary rod having an outer face at an end of the second rod;   an implant configured to be coupled to an end of the second rod, the implant including:
 an expandable implant head that, when expanded, defines a volume; and 
 an implant base extending away from the implant head, the implant base having an inner face; 
 wherein the inner face of the implant base includes threads; 
   wherein the outer face of the end of the second rod includes threads configured to threadingly engage the threads on the inner face of the implant base; and further   wherein, in operation, the second rod is coupled to the first rod, the implant is coupled to the second rod, the implant head is in an expanded state, and the central axis points to the volume.   
     
     
         97 . The apparatus of  claim 96  wherein:
 the implant base has an outer face, the outer face of the implant base including threads; and 
 the end of the second rod defines a threaded opening configured to threadingly engage the threads on the outer face of the implant base. 
 
     
     
         98 . The apparatus of  claim 96  wherein:
 the implant is a first implant and the expandable head is a first expandable head, further comprising a second implant including a second expandable head, the second implant being configured to be coupled to the end of the second rod, and the second implant including a base extending away from the second head, the base including threads; and 
 wherein the end of the second rod is configured to threadingly engage the threads of the base of the second head. 
 
     
     
         99 . The apparatus of  claim 96  wherein:
 the implant is a first implant and the expandable head is a first expandable head; further comprising: 
 a second implant including a second expandable head, the second implant being configured to be coupled to the end of the second rod; and 
 wherein the end of the second rod comprises a first end; further comprising 
 a third implant including:
 a third expandable head configured to be coupled to a second end of the second rod; and 
 a base extending away from the third head, the base including threads; 
 
 wherein a second end of the second rod defines an opening sized to receive the base of the third head, and the second end of the second rod is configured to threadingly engage the threads of the base of the third head. 
 
     
     
         100 . Apparatus for placement in an interior of a bone, the apparatus comprising:
 a cannulated intramedullary rod having a first end and a second end opposite the first end;   an implant configured to be coupled to the first end, the implant having an expandable implant head, an implant tail, and an implant base extending between the head and the tail; and   an end cap configured to be coupled to the second end;   wherein the implant is configured to be coupled to the first end such that the implant head extends away from the first end and the implant tail is seated in an interior of the rod.   
     
     
         101 . The apparatus of  claim 100  further comprising a threaded member coupled to, and extending away from, the end cap along a central axis of the end cap, wherein:
 an inner face of the implant tail is threaded; and 
 the threaded member is threaded to mate with the implant tail; 
 wherein in operation: 
 the threaded member extends through an interior of the rod, along a longitudinal axis of the rod, and is engaged with the implant threaded surface. 
 
     
     
         102 . The apparatus of  claim 100  wherein the implant base is a portion of the implant tail. 
     
     
         103 . A method for repairing a bone having a surface and an interior, the bone having an elongated portion, a head including an articular surface, and a neck positioned between the elongated portion and the head, the method comprising:
 placing a first intramedullary rod and an implant including a mesh cage coupled to an end of the first rod in the interior such that at least a portion of the mesh cage is positioned in the head;   placing a second intramedullary rod in the interior such that the second rod extends along a length of the elongated portion, the placing including coupling the second rod to the first rod;   advancing a screw through a hole defined by the second intramedullary rod; and   anchoring a distal end of the screw in the head of the articular surface, the anchoring comprising driving the distal end into the mesh cage.   
     
     
         104 . The method of  claim 103  further comprising coupling the first rod to the implant, wherein:
 the implant includes a base extending away from the mesh cage, the base including threads; and 
 the coupling of the mesh cage to the first rod includes threadingly engaging the base with a threaded portion of the first rod. 
 
     
     
         105 . The method of  claim 103  further comprising coupling the first rod to the implant, wherein:
 the implant includes a base extending away from the mesh cage; and 
 the coupling of the first rod to the implant includes positioning the base in an opening defined by the first rod. 
 
     
     
         106 . The method of  claim 105  further comprising threadingly engaging threads on a face of the hub with threads on a face of the rod. 
     
     
         107 . The method of  claim 105  further comprising threadingly engaging threads on a face of the base with threads on a face of the rod. 
     
     
         108 . The method of  claim 103  when the mesh cage is an expandable mesh cage, the method further comprising:
 expanding the mesh cage; and 
 after the expanding, and before the placing of the first rod, coupling the mesh cage to the first rod. 
 
     
     
         109 . The method of  claim 103  when the mesh cage is an expandable mesh cage, the method further comprising, after the positioning of the first rod and the implant in the head of the bone, expanding the mesh cage, wherein:
 the first rod is cannulated; 
 the implant includes an implant tail coupled to the mesh cage; and 
 expanding the mesh cage includes advancing a threaded member along an interior of the first rod and engaging the threaded member with threads in an inner surface of the implant tail. 
 
     
     
         110 . The method of  claim 109  further comprising, after the expanding of the mesh cage, placing an end cap on a second end of the first rod, the second end being opposite the first end. 
     
     
         111 . The method of  claim 103  wherein the mesh cage is an expandable mesh cage further comprising expanding the mesh cage from a first volume to a second volume. 
     
     
         112 . The method of  claim 103  wherein the coupling of the second rod to the first rod includes positioning the first rod in an opening defined by the second rod. 
     
     
         113 . The method of  claim 103  wherein the coupling of the second rod to the first rod includes positioning the second rod in an opening defined by the first rod. 
     
     
         114 . The method of  claim 103  when the screw is a first screw, the implant is a first implant, the mesh cage is a first mesh cage, and an end of the second rod is coupled to a second implant including a second mesh cage, the method further comprising advancing a second screw through the surface and into the second cage. 
     
     
         115 . The method of  claim 114  when the end of the second rod is a first end and a second end of the second rod is coupled to a third mesh cage, the method further comprising advancing a third screw through the surface and into the third cage 
     
     
         116 . The method of  claim 103 , when the screw is a first screw and the hole is a first hole, further comprising:
 driving a second screw through a second hole defined by the second intramedullary rod; and   anchoring a distal end of the second screw in the head, the anchoring comprising driving the distal end of the second screw into the mesh cage.   
     
     
         117 . The method of  claim 116  wherein:
 the first screw is advanced through the first hole along a first axis; 
 the second screw is advanced through the second hole along a second axis; and 
 the first axis is parallel to the second axis. 
 
     
     
         118 . The method of  claim 116  wherein:
 the first screw is advanced through the first hole along a first axis; 
 the second screw is advanced through the second hole along a second axis; and 
 the first axis is oblique to the second axis. 
 
     
     
         119 . A method for repairing a bone having a surface and an interior, the bone having an elongated portion, a head including an articular surface, and a neck positioned between the elongated portion and the head, the method comprising:
 placing an intramedullary rod coupled to a mesh cage at an end of the rod in the interior such that at least a portion of a mesh cage is positioned in the head;   placing a plate on the surface, the placing including coupling the plate to the rod;   driving a screw through a hole defined by the plate; and   anchoring a distal end of the screw in the head, the anchoring comprising driving the distal end into the mesh cage.   
     
     
         120 . The method of  claim 119  further comprising, before the placing of the rod, coupling the mesh cage to the rod. 
     
     
         121 . The method of  claim 120  further comprising, before the placing of the rod and the coupling of the plate to the rod, expanding the mesh cage. 
     
     
         122 . The method of  claim 119  further comprising expanding the mesh cage in the interior. 
     
     
         123 . The method of  claim 119  wherein:
 the end of the rod is a first end; and 
 the coupling of the plate and the rod includes placing a second end of the rod inside an opening defined by the plate, the second end being opposite the first end. 
 
     
     
         124 . The method of  claim 119 , when the screw is a first screw and the hole is a first hole, further comprising:
 driving a second screw through a second hole defined by the plate; and   anchoring a distal end of the second screw in the head, the anchoring comprising driving the distal end of the second screw into the mesh cage.   
     
     
         125 . The method of  claim 124  wherein:
 the first screw is advanced through the first hole along a first axis; 
 the second screw is advanced through the second hole along a second axis; and 
 the first axis is parallel to the second axis. 
 
     
     
         126 . The method of  claim 124  wherein:
 the first screw is advanced through the first hole along a first axis; 
 the second screw is advanced through the second hole along a second axis; and 
 the first axis is oblique to the second axis. 
 
     
     
         127 . A method for repairing a bone having a surface and an interior, the method comprising:
 placing an intramedullary rod in the interior;   advancing an expandable implant through a lumen defined by an interior of the rod;   positioning a head of the implant in the interior and a tail of the implant in the lumen;   expanding the head to form a mesh cage; and   anchoring the rod to the bone, the anchoring including driving a first screw through the surface and into the mesh cage.   
     
     
         128 . The method of  claim 127  further comprising anchoring the tail implant to the rod. 
     
     
         129 . A method for implanting an expandable implant in an interior of a calcaneus bone having a bone surface, the method comprising:
 making an incision in soft tissue covering a posterior facet of the bone below a termination point, on the bone, of an Achilles tendon;   providing, through the incision, an access hole on the bone surface;   advancing the expandable implant through the access hole and into the interior;   positioning a distal end of the implant in the interior; and   expanding the implant in the interior to form a mesh cage such that a first portion of the mesh cage is adjacent a sinus tarsi space and a second portion of the mesh cage is adjacent a distal facet of the bone.   
     
     
         130 . The method of  claim 129  when the incision is a first incision further comprising:
 making a second incision in soft tissue covering a lateral side of the posterior facet of the calcaneus; and 
 visualizing a position of a sinus space relative to a talus bone through the second incision. 
 
     
     
         131 . The method of  claim 129  further comprising, after the expanding, anchoring a distal end of a screw in the interior, the anchoring comprising:
 driving the screw through the bone surface; and 
 advancing a distal tip of the screw into the mesh cage. 
 
     
     
         132 . The method of  claim 129  further comprising:
 positioning a plate on the posterior facet of the bone; and 
 after the expanding, driving a screw through a hole defined by the plate and into the mesh cage. 
 
     
     
         133 . The method of  claim 132  wherein the positioning of the plate is performed after the advancing the expandable implant into the interior. 
     
     
         134 . The method of  claim 132  wherein:
 the positioning the plate is performed before the advancing of the expandable implant into the interior; and 
 the advancing is performed through an opening in the plate. 
 
     
     
         135 . A method for implanting an expandable implant in an interior of a calcaneus bone having a bone surface, the method comprising:
 forming a split in an Achilles tendon extending along a posterior facet of the bone;   making an incision, through the split, in soft tissue covering the posterior portion facet   providing, through the incision, an access hole on the bone surface;   advancing the expandable implant through the access hole and into the interior;   positioning a distal end of the implant in the interior;   expanding the implant in the interior to form a mesh cage such that a portion of the mesh cage is adjacent a distal facet of the calcaneus.   
     
     
         136 . The method of  claim 135  when the incision is a first incision further comprising:
 making a second incision in soft tissue covering a lateral side of the posterior facet of the calcaneus; and 
 visualizing a position of a sinus tarsi space relative to a talus bone through the second incision. 
 
     
     
         137 . The method of  claim 135  further comprising, after the expanding, anchoring a distal end of a screw in the interior, the anchoring comprising:
 driving the screw through the bone surface; and 
 advancing a distal tip of the screw into the expandable implant. 
 
     
     
         138 . The method of  claim 135  further comprising:
 positioning a plate on the posterior facet; and 
 driving a screw through a hole defined by the plate and into the implant. 
 
     
     
         139 . The method of  claim 138  wherein the positioning the plate is performed after the advancing the expandable implant. 
     
     
         140 . The method of  claim 138  wherein:
 the positioning the plate is performed before the advancing the expandable implant; and 
 the advancing is performed through an opening in the plate. 
 
     
     
         141 . A method for implanting an expandable implant in an interior of a calcaneus bone having a bone surface, the method comprising:
 making an incision in soft tissue covering a distal facet of the bone;   providing, through the incision, an access hole on the bone surface;   advancing the expandable implant through the access hole and into the interior;   positioning a distal end of the implant in the interior and substantially perpendicular to a longitudinal axis extending along a length of the bone; and   expanding the implant in the interior to form a mesh cage such that a hub of the implant is adjacent the talus.   
     
     
         142 . The method of  claim 141  when the incision is a first incision further comprising:
 making a second incision in soft tissue covering a lateral side of a posterior facet of the calcaneus; and 
 visualizing a position of a sinus space relative to a talus bone through the second incision. 
 
     
     
         143 . The method of  claim 141  further comprising, after the expanding, anchoring a distal end of a screw in the interior, the anchoring comprising:
 driving the screw through the bone surface; and 
 advancing a distal tip of the screw into the expandable implant. 
 
     
     
         144 . The method of  claim 141  further comprising:
 positioning a plate on the distal facet; and 
 driving a screw through a hole defined by the plate and into the implant. 
 
     
     
         145 . Apparatus for bone repair comprising:
 a first mesh that defines a longitudinal axis and is expandable about the axis;   a second mesh that is expandable about the axis between the axis and the first mesh;   wherein:   each of the first and second mesh is configured to be longitudinally fixed to a central axis member that lies along the axis;   the first mesh has a first stress-strain modulus corresponding to compression of the first mesh along a direction not parallel to the axis; and   the second mesh has a second stress-strain modulus corresponding to compression of the second mesh along the direction.   
     
     
         146 . The apparatus of  claim 145  wherein the second modulus is greater than the first modulus. 
     
     
         147 . The apparatus of  claim 145  wherein:
 the first mesh has a first thickness; 
 the second mesh has a second thickness; and 
 the second thickness is greater than the first thickness. 
 
     
     
         148 . The apparatus of  claim 147  wherein:
 the first thickness is in the range 0.010 in. to 0.020 in.; and 
 the second thickness is in the range 0.015 in. to 0.040 in. 
 
     
     
         149 . Apparatus for bone repair, the apparatus comprising:
 an implant head that includes a mesh anchoring substrate that is expandable away from a longitudinal axis of the substrate, and a base that defines an opening for receiving along the axis an elongated support having a catch;   the support, the support configured to engage a hub at an end of the substrate that is opposite the base; and   a latch extending from the base in a direction away from the substrate and configured to engage the catch to prevent withdrawal of the elongated support from the base.   
     
     
         150 . The apparatus of  claim 149  wherein;
 the latch includes an arm and a protrusion from the arm, the latch configured to insert the protrusion into a recess in the elongated support when the protrusion is positioned at the recess; and 
 the catch defines a limit of the recess. 
 
     
     
         151 . The apparatus of  claim 150  wherein:
 the base defines a cylindrical outer surface at a first radius from the axis; 
 the arm has a length that is disposed at the first radius in a state in which the protrusion is in the recess; and 
 the length is disposed at a second radius that is greater than the first radius in a state in which the protrusion is in contact with the elongated member at a location outside the recess. 
 
     
     
         152 . The apparatus of  claim 149  wherein:
 the elongated support defines a recess; and 
 the recess includes the catch. 
 
     
     
         153 . The apparatus of  claim 149  wherein:
 the anchoring substrate is pretreated to induce contraction of the substrate along the axis to collapse the substrate; and 
 the contraction increases frictional engagement between the latch and the wall. 
 
     
     
         154 . The apparatus of  claim 149  wherein:
 the support includes a threaded member that is configured to reduce a length of the support by threaded engagement with an internally threaded cannulated member; and 
 reduction of the length expands the anchoring substrate. 
 
     
     
         155 . Apparatus for bone repair, the apparatus comprising an implant that includes:
 a mesh anchoring substrate that is expandable away from a longitudinal axis of the substrate; and   a tail at an end of the substrate, the tail configured for sliding engagement in a slot of a plate;   wherein the slot in operation fixes the implant relative to the plate axially along the axis, rotationally about the axis, and rotationally about the plate.   
     
     
         156 . The apparatus of  claim 155  further comprising the plate. 
     
     
         157 . The apparatus of  claim 156  wherein the plate is keyed to a groove in the tail. 
     
     
         158 . The apparatus of  claim 157  wherein:
 the plate defines a clearance opening having a first width, and the slot, the slot having a second width that is less than the first width; 
 the first width is greater than a diameter of the tail; 
 the second width is less than the diameter; and 
 the second width is greater than a thickness of the tail at the groove. 
 
     
     
         159 . The apparatus of  claim 158  wherein;
 the groove is of a plurality of grooves; and 
 the plurality of grooves define a sliding direction along which the plate is configured to slide for insertion of the tail in the slot. 
 
     
     
         160 . The apparatus of  claim 159  wherein in operation the sliding direction is oblique to the axis. 
     
     
         161 . Apparatus for bone repair, the apparatus comprising an implant head that includes:
 a mesh anchoring substrate that is expandable away from an elongated central support; and   a support;   wherein the support defines a transverse bore that in operation is disposed between a first end of the substrate and a second end of the substrate.   
     
     
         162 . The apparatus of  claim 161  wherein the bore is sized for clearance of a screw that is configured for penetration and engagement of the substrate. 
     
     
         163 . The apparatus of  claim 161  wherein the bore has a diameter that is 0.0005″-0.001″ smaller than a thread diameter of a screw that is configured for penetration and engagement of the substrate. 
     
     
         164 . The apparatus of  claim 163  wherein the thread diameter is a largest thread diameter on the screw. 
     
     
         165 . The apparatus of  claim 161  wherein an inner face of the bore includes threads for threadingly engaging a screw that is configured for penetration and engagement of the substrate. 
     
     
         166 . Apparatus for placement in an interior of a bone, the apparatus comprising:
 a first intramedullary rod defining a screw hole having a central axis;   a second intramedullary rod configured to be coupled to the first rod;   an implant configured to be coupled to an end of the second rod, the implant including an expandable implant head that, when expanded, defines a volume; and   an elongated member comprising a screw configured to be advanced through the screw hole and including a threaded portion configured to be anchored in the implant head when the implant head is expanded;   wherein, in operation, the second rod is coupled to the first rod, the implant is coupled to the second rod, the implant head is in an expanded state, the central axis points to the volume, the elongated member is seated in the screw hole, and the threaded portion is anchored in the implant head.   
     
     
         167 . The apparatus of  claim 166  wherein the threaded portion is positioned at a distal end of the elongated member.