Method and apparatus for shaping a proximal tibial surface

Claim 1

A method of preparing a human tibia having a superior proximal surface and a central long axis defined by the interior of a tubular shaft of hard compact bone to receive a superior proximal tibial knee prosthesis, said method comprising the steps of (A) resecting a small amount of the superior proximal surface of the tibia to form an approximately planar surface which is approximately transverse to the central long axis of the tibia, (B) determining the approximate location on the superior proximal surface of the tibia which corresponds to the central long axis of the tibia, (C) advancing a reamer/alignment guide through said superior proximal surface at said location along the interior of said tubular shaft of the tibia for a sufficient distance to enable the central long axis of said reamer/alignment guide to correspond with the central long axis of the tibia, said reamer/alignment guide comprising a rod having a first portion which is intended to enter the interior of said tubular shaft of the tibia which portion (1) is of an outside diameter approximating the narrowest portion of said interior and (2) has a plurality of cutting ridges situated about its circumference, the remaining portion of said rod acting as a guide handle which extends outwardly from said proximal surface and is concentric with the central long axis of said first portion, said handle further having a means thereon for imparting a twisting motion to said reamer/alignment guide, (D) attaching a plateau planer to said guide handle, said planer comprising a planar abrading surface, a handle and a shaft connecting said planar abrading surface to said handle, said planer having a passage therethrough adapted to cooperatively engage said guide handle and to allow the planar abrading surface to be transversely rotated about the central long axis of said guide handle while it is in contact with the proximal surface of said tibia to flatten said proximal surface transversely with respect to the central long axis of the guide handle, said planar abrading surface containing a plurality of space cutting ridges which are planar and are situated transverse to the central long axis of said guide handle and further having a recessed area thereon to avoid trauma to anatomical members found about the intercondylar fossa of the proximal surface of the tibia, (E) modifying said proximal surface of the tibia through the use of said planer until said surface is smooth, planar and transverse to the central long axis of said guide handle, (F) trimming any remaining bone from the proximal surface of the tibia to present a smooth, flat surface on which a proximal tibial prosthesis can be affixed, and (G) removing the reamer/alignment guide.

Claim 2

A method of preparing a human tibia having a superior proximal surface and a central long axis defined by the interior of a tubular shaft of hard compact bone to receive a superior proximal tibial knee prosthesis, said method comprising the steps of (A) resecting a small amount of the superior proximal surface of the tibia to form an approximately planar surface which is approximately transverse to the central long axis of the tibia, (B) determining the approximate location on the superior proximal surface of the tibia which corresponds to the central long axis of the tibia, (C) advancing a reamer/alignment guide through said superior proximal surface at said location along the interior of said tubular shaft of the tibia for a sufficient distance to enable the central long axis of said reamer/alignment guide to correspond with the central long axis of the tibia, said reamer/alignment guide comprising a rod having a first portion which is intended to enter the interior of said tubular shaft of the tibia which portion (1) is of an outside diameter approximating the narrowest portion of said interior and (2) has a plurality of cutting ridges situated about its circumference, the remaining portion of said rod acting as a guide handle which extends outwardly from said proximal surface and is concentric with the central long axis of said first portion, said handle further having a means thereon for imparting a twisting motion to said reamer/alignment guide, (D) attaching a plateau planer to said guide handle, said planer comprising a planar abrading surface, a handle and a shaft connecting said planar abrading surface to said handle, said planer having a passage therethrough adapted to cooperatively engage said guide handle and to allow the planar abrading surface to be transversely rotated about the central long axis of said guide handle while it is in contact with the proximal surface of said tibia to flatten said proximal surface transversely with respect to the central long axis of the guide handle, said planar abrading surface containing a plurality of space cutting ridges which are planar and are situated transverse to the central long axis of said guide handle and further having a recessed area thereon to avoid trauma to anatomical members found about the intercondylar fossa of the proximal surface of the tibia, (E) modifying said proximal surface of the tibia through the use of said planer until said surface is smooth, planar and transverse to the central long axis of said guide handle, (F) trimming any remaining bone from the proximal surface of the tibia to present a smooth, flat surface on which a proximal tibial prosthesis can be affixed, and (G) removing the reamer/alignment guide.