Surgical tool

A surgical tool for checking the flexion and extension gaps located between previously resected surfaces of a proximal tibia and corresponding posterior and distal femoral condyles during knee arthroplasty, the tool comprising a central body portion from which extends a handle;

• a first paddle flange adapted for insertion into a flexion or extension gap, the first paddle flange being mounted on the central body portion;
• a second paddle flange substantially parallel to the first paddle flange and cooperating therewith in a first position to define, between an upper surface of an upper one of said first and second paddle flanges and a lower surface of a lower one of said first and second paddle flanges, a first distance corresponding to a minimum gap and movable relative to the first paddle flange to define a second distance between the said upper surface and the said lower surface corresponding to a maximum gap;
• the second paddle flange being mounted so as to be movable relative to the central body portion of the tool to vary the gap defined by the first and second paddle flanges;
• hand operable means arranged to cause movement of the second paddle flange in a gap-increasing direction to enable determination of the size of the flexion gap or the extension gap;
• and means providing to a surgeon using the tool indicia comparative of the size of the flexion or extension gap being checked with the size of a flexion or extension gap checked in a previous operation of the tool.