Intramedullary fixation device and methods for bone fixation and stabilization

A kit for bone fixation and stabilization, comprising:

• an intramedullary fixation device, comprising:
• an arrowhead-shaped distal head comprising a distal end having a tip, the distal head having first, second, third, and fourth outwardly facing side surfaces forming a pyramidal shape, the first and third side surfaces being opposed from each other and forming a first angle, and the second and fourth side surfaces being opposed from each other and forming a second angle, the second angle being different than the first angle, each of the first and third side surfaces having a proximal edge configured to engage tissue and inhibit rotational movement and inhibit axial movement of the distal head in a proximal direction, the distal head being sized to fit within an intramedullary canal of a more-distal phalanx portion of one of a finger and a toe;
• an arrowhead-shaped proximal head comprising a proximal end having a tip, the proximal head having fifth, sixth, seventh, and eighth outwardly facing side surfaces, the fifth and seventh side surfaces being opposed from each other and forming a third angle, and the sixth and eighth side surfaces being opposed from each other and forming a fourth angle, the third angle being different than the fourth angle, each of the fifth and seventh side surfaces having a distal edge configured to engage tissue and inhibit rotational movement and inhibit axial movement of the proximal head in a distal direction, the proximal head being sized to fit within an intramedullary canal of a more-proximal phalanx portion of said one of a finger and a toe;
• and
• a rigid body extending between and connecting the distal head and the proximal head, the body having a rigidity sufficient to withstand bending loading applied by the phalanges, the rigid body comprising a main portion, a distal neck portion connecting the rigid body to the distal head, and a proximal neck portion connecting the rigid body to the proximal head, the distal and proximal neck portions having a cross-sectional area smaller than a cross-section area of the main portion such that tissue ingrowth may occur behind the distal head around the distal neck portion and behind the proximal head around the proximal neck portion;
• and
• insertion forceps configured to securably grasp the intramedullary fixation device, the insertion forceps comprising:
• a first nose piece having a first recess formed therein, the first recess being sized to receive a portion of the body of the intramedullary fixation device;
• a second nose piece having a second recess formed therein, the second recess being sized to receive a portion of the body of the intramedullary fixation device, the first and second nose pieces being cooperatively arranged to securely grip the body of the intramedullary fixation device sufficiently to prevent rotation and axial displacement under normal insertion conditions.

An intramedullary fixation device used in bone fixation and stabilization, comprising:

• an arrowhead-shaped distal head comprising a distal end, the distal head having first, second, third, and fourth outwardly facing side surfaces forming a pyramidal shape, the first and third side surfaces being opposed from each other and forming a first angle, and the second and fourth side surfaces being opposed from each other and forming a second angle, the second angle being different than the first angle, the first, second, third, and fourth side surfaces converging toward the distal end, each of the first and third side surfaces having a proximally projecting edge configured to engage tissue and inhibit rotational movement and inhibit axial movement of the distal head in a proximal direction, the distal head being sized to fit within an intramedullary canal of a more-distal phalanx portion of one of a finger and a toe;
• an arrowhead-shaped proximal head comprising a proximal end, the proximal head having fifth, sixth, seventh, and eighth outwardly facing side surfaces, the fifth and seventh side surfaces being opposed from each other and forming a third angle, and the sixth and eighth side surfaces being opposed from each other and forming a fourth angle, the third angle being different than the fourth angle, the fifth, sixth, seventh, and eighth side surfaces converging and meeting at the proximal end, each of the fifth and seventh side surfaces having a distally projecting edge configured to engage tissue and inhibit rotational movement and inhibit axial movement of the proximal head in a distal direction, the proximal head being sized to fit within an intramedullary canal of a more-proximal phalanx portion of said one of a finger and a toe;
• and
• a rigid body extending between and connecting the distal head and the proximal head, the body having a rigidity sufficient to withstand bending loading applied by the phalanges, the rigid body being sized and shaped to fit within the intramedullary canals of both the more-distal phalanx portion and the more-proximal phalanx portion, the distal head, proximal head, and rigid body being sized and shaped so that the more-distal phalanx portion may abut directly against the more-proximal phalanx portion when the distal head is in the more-distal phalanx portion and the proximal head is in the more-proximal phalanx portion.