Asahi Kogaku Kogyo Kabushiki Kaisha

Other

Pentax Corporation

Hoya Corporation

Hiromi Matsuzaki

Satoshi Ojima

Yoshie Tominaga

Masashi Nakamura

Yasuhiko Hirayama

Haruko Ikata

Bone replacement material to be used by being packed into a bone defective part, wherein the bone replacement material consists essentially of a calcium phosphate based compound and is formed into a pellet and satisfies both of the following conditions (I) and (II): (I) porosity is equal to or less than 75%; and (II) collapsing strength is equal to or more than 15 Mpa. The pellet has a roughly polyhedral shape and is defined by a plurality of surfaces including a pair of opposite, non-parallel surfaces and a surface adjoining to the pair of opposite, non-parallel surfaces, one of the opposite, non-parallel surfaces being inclined at a predetermined angle with respect to the other of the opposite, non-parallel surfaces. The one of the opposite, non-parallel surfaces is non-adjoined with the other of the opposite, non-parallel surfaces in the pellet. The other of the opposite, non-parallel surfaces is perpendicular to the surface adjoining to the pair of opposite, non-parallel surfaces.

Bone replacement material

A bone replacement material for use in a treatment for repairing a vertebral body compression fracture is formed into a pellet having a roughly polyhedral shape. Each pellet having the roughly polyhedral shape has a pair of opposite surfaces, in which one of the opposite surfaces is inclined with respect to the other surface for a predetermined angle. The angle is preferably in the range of 10 to 60&#xb0;. Further, the volume of each pellet of the bone replacement materialis in the range of 13 to 239 mm3. Furthermore, the bone replacement material is formed of calcium phosphate based compound having the Ca/P ratio of 1.0 to 2.0. By using such a bone replacement material, it is possible to carry out packing operation of the bone replacement material into a collapsed vertebral body smoothly, reliably and safely.

Various surgical instruments for use in the treatment of vertebral body compression fractures, used respectively for: widening a working path; reducing deformity; inserting a filler; and impacting a filler are provided. A set of surgical instruments including these instruments makes it possible to treat collapsed vertebral bodies easily and reliably are provided. The set includes a guide rod(an instrument for widening a working path), a vertical elevator(an instrument for reducing deformity), a horizontal elevator(an instrument for reducing deformity), an inserter(an instrument for inserting a filler), and an impactor(an instrument for impacting a filler). The guide rodis used for widening a pathformed in a collapsed vertebral bodyThe vertical elevatoris used for returning the upper anterior portion of the collapsed vertebral bodyto a substantially original shape. The horizontal elevatoris used for returning the upper middle portion of the collapsed vertebral bodyto a substantially original shape. The inserteris used for inserting a filler into the reduced vertebral bodyThe impactoris used for increasing the density of the filler inserted into the reduced vertebral body

Surgical instruments and a set of surgical instruments for use in treatment of vertebral bodies

An artificial vertebra spacer is embedded in and bridges a space between two adjacent vertebrae which are positioned superiorly and inferiorly of a removed intervertebral disk, respectively. The artificial vertebra spacer includes a hollow cylindrical member, and a helical screw thread disposed integrally on and extending helically around the hollow cylindrical member. A substantially rectangular flange portion is provided at one end of the hollow cylindrical member. The flange portion is provided with at least one hole through which at least one screw passes to fix the spacer.

Prosthesis for spanning a space formed upon removal of an intervertebral

An artificial vertebra spacer is embedded in and bridges a space between two adjacent vertebrae which are positioned superiorly and inferiorly of a removed intervertebral disk, respectively. The artificial vertebra spacer includes a hollow cylindrical member, and a helical screw thread disposed integrally on and extending helically around the hollow cylindrical member. An annular plate has a tubular member fitted in an axial end of the artificial vertebra spacer and a circular flange extending radially outwardly from the tubular member. The circular flange is fastened to the helical screw thread by screws when the artificial vertebra spacer is embedded in the vertebrae. Each of the artificial vertebra spacer, the annular plate, and the at least one screw is made of a titanium alloy.

A vertebral connecting plate assembly includes a vertebral connecting plate which is provided, on its opposite ends, with vertebra connecting portions to be connected to associated vertebral members or bodies. The vertebra connecting portions have threaded holes, and the set screws of the present invention have engaging screw portion, which are engaged in the associated threaded holes of the vertebral connecting plate. Thrusting screw portions of the set screws, which are thrust in the vertebral members or bodies, have a pitch (P1) larger than the pitch (P2) of the engaging screw portions.

Vertebral connecting plate

An artificial intervertebral disc comprises a pair of end bodies which are provided, on their outer surfaces, with apatite layers. The disc includes a medical synthetic polymeric intermediate which is held between the end bodies through connecting members.

Growing community of inventors

Tokyo, Japan

Hiromi Matsuzaki