Flexible intramedullary rod

Abstract

An elongated rod for insertion into a bowed canal of a bone such as a femoral medulla of a femur bone, wherein the canal is bowed in one plane. The rod has a longitudinal axis disposed on a first plane and one or more cutouts formed in at least a portion of a length of the rod and on opposite sides of the first plane. The rod is flexible along a second plane which is co-planar with the bowed canal plane and which is disposed on the longitudinal axis and perpendicular to the first plane.

1 . A surgical instrument for insertion into a bowed canal of a bone, the canal bowed in one plane, the instrument comprising:
 an elongated rod having a longitudinal axis disposed on a first plane, and one or more cutouts formed in at least a portion of a length of the rod and on opposite sides of the first plane, wherein the rod is flexible along a second plane which is coplanar with the bowed canal plane and which is disposed on the longitudinal axis and perpendicular to the first plane.   
   
   
       2 . The surgical instrument of  claim 1 , wherein the elongated rod is generally solid. 
   
   
       3 . The surgical instrument of  claim 1 , wherein the rod is substantially rigid along the first plane. 
   
   
       4 . The surgical instrument of  claim 1 , wherein the rod is capable of resiliently flexing along the second from a radius of about 0 to degrees to 9 degrees. 
   
   
       5 . The surgical instrument of  claim 1 , wherein the cutouts include one or more grooves extending along at least a portion of the longitudinal axis and on opposite sides of the first plane. 
   
   
       6 . The surgical instrument of  claim 1 , wherein the cutouts have a generally flat shape extending along at least a portion of the longitudinal axis and on opposite sides of the first plane. 
   
   
       7 . The surgical instrument of  claim 1 , wherein the cutouts have a generally semi-circular cross-sectional shape along the second plane. 
   
   
       8 . The surgical instrument of  claim 1 , wherein the rod has a first end adapted for insertion into the canal of a bone and a second end adapted for attachment to a tool to support the rod. 
   
   
       9 . A surgical instrument kit comprising:
 an elongated rod for insertion into a bowed canal of a bone, the canal bowed in one plane, the rod having a longitudinal axis disposed on a first plane, the rod is flexible along a second plane which is co-planar with the bowed canal plane and which is disposed on the longitudinal axis and perpendicular to the first plane, and the rod has a first end adapted for insertion into the bowed canal of a bone and a second end adapted for attachment to a tool to support the rod; and   a tool having an attachment portion for attachment to the second end of the rod.   
   
   
       10 . The surgical instrument kit of  claim 9 , wherein the elongated rod is generally solid. 
   
   
       11 . The surgical instrument kit of  claim 9 , wherein the rod is substantially rigid along the first plane. 
   
   
       12 . The surgical instrument kit of  claim 9 , wherein the rod is capable of resiliently flexing along the second plane from a radius of about 0 to degrees to 9 degrees. 
   
   
       13 . The surgical instrument kit of  claim 9 , wherein the cutouts include one or more grooves extending along at least a portion of the longitudinal axis and on opposite sides of the first plane. 
   
   
       14 . The surgical instrument kit of  claim 9 , wherein the cutouts have a generally flat shape extending along at least a portion of the longitudinal axis and on opposite sides of the first plane. 
   
   
       15 . The surgical instrument kit of  claim 9 , wherein the cutouts have a generally semi-circular cross-sectional shape along the second plane. 
   
   
       16 . The surgical instrument kit of  claim 9 , wherein the tool has a handle rotatably coupled to the attachment portion for rotating the rod. 
   
   
       17 . A method of using a surgical instrument comprising:
 preparing a canal along a longitudinal axis of a bone, wherein the longitudinal axis is disposed on a first plane and a second plane, wherein the first plane and the second plane are perpendicular to each other, and wherein the canal is bowed along a plane which is co-planar with the second plane; and   inserting an elongated rod into the canal, wherein the rod is resiliently flexible along the second plane which is co-planar with the bowed canal plane and which is disposed on the longitudinal axis and perpendicular to the first plane; and   bending the rod when at least a portion of the rod is inserted into the canal, the rod bends along the second plane of the canal such that the rod substantially conforms to the curved shape of the canal along the second plane of the canal.   
   
   
       18 . The surgical method of  claim 17 , further comprising attaching the tool to one of the rod. 
   
   
       19 . The surgical method of  claim 17 , wherein the first canal of the bone is a femoral medulla of a femur bone of a human body. 
   
   
       20 . The surgical method of  claim 19 , wherein the first plane corresponds to a frontal or coronal plane that separates a human body into anterior and posterior parts and the second plane is parallel to a sagittal plane corresponding to a median plane which separates a human body into left and right side parts. 
   
   
       21 . The surgical method of  claim 19  wherein forming the canal includes drilling the canal along a longitudinal axis of the bone. 
   
   
       22 . The surgical method of  claim 19  further comprising detaching the tool from the rod and attaching a cutting block to the rod. 
   
   
       23 . The surgical method of  claim 22  further comprising making anterior, posterior, anterior-chamfer and posterior-chamfer cuts on the bone. 
   
   
       24 . The surgical method of  claim 19  wherein forming the canal includes drilling an entrance hole between condyles of the femur bone. 
   
   
       25 . The surgical method of  claim 19  further comprising using computed tomography (CT) data to determine an optimal sagittal orientation of a femoral component for attachment to the femur bone. 
   
   
       26 . The surgical method of  claim 25  further comprising attaching a femoral component to the femur bone.