Abstract: An apparatus in a total knee replacement and arthroplasty operation for measuring a joint gap and ligament balance between a osteotomized surface at a femoral distal end and a osteotomized surface at a tibial proximal end. The apparatus is provided with a base 10, from which an engaging plate 14 extends by way of an arm, so that the engaging plate 14 contacts with the osteotomized surface at the tibial proximal end. A moving body 18 is vertically movably connected to the base 10, from which moving body 18 an arm 20 extends, to which arm a supporting plate 22 is rotatably mounted about a central axis. The supporting plate 22 has, at its top surface, a projected portion 48. to which an auxiliary guiding piece 50 is connected under a snap like fitted manner. A femoral component 52 is mounted, at its groove portion 54, to the osteotomized surface at the femoral distal end.

Abstract: An apparatus in a total knee replacement and arthroplasty operation for measuring a joint gap and ligament balance between a osteotomized surface at a femoral distal end and a osteotomized surface at a tibial proximal end. The apparatus is provided with a base 10, from which an engaging plate 14 extends by way of an arm, so that the engaging plate 14 contacts with the osteotomized surface at the tibial proximal end. A moving body 18 is vertically movably connected to the base 10, from which moving body 18 an arm 20 extends, to which arm a supporting plate 22 is rotatably mounted about a central axis. The supporting plate 22 has, at its top surface, a projected portion 48. to which an auxiliary guiding piece 50 is connected under a snap like fitted manner. A femoral component 52 is mounted, at its groove portion 54, to the osteotomized surface at the femoral distal end.