JP2012115356A5

JP2012115356A5 -

Info

Publication number: JP2012115356A5
Application number: JP2010265989A
Authority: JP
Filing date: 2010-11-30
Publication date: 2013-12-05

Description

ステム部Ｓと骨頭部Ｈとはともに硬質の素材により形成され、これらが嵌合により直接接触して固定されているために、骨頭部Ｈにかかる力は、ほぼすべてステム部Ｓに伝わる。このような大腿骨Ｆに埋め込まれるステム部Ｓにかかる力は、ステム部Ｓと大腿骨Ｆとの接着面において、接着の緩みや、マイクロモーションを誘発し、ステム部Ｓの磨耗や折損の一因となったり、大腿部痛や大腿骨骨折の一因となったりしていると考えられる。
逆に、ステム部Ｓにかかる力も骨頭部Ｈに減衰することなく伝達するため、これも人工股関節置換術後の患者に対する臼蓋コンポーネントの緩みの一因となったり、人工骨頭置換術後の患者に対する臼蓋軟骨の変形や変形性関節症の一因となったりしていると考えられる。
本発明は、このような観点に立ち、人工股関節の大腿骨コンポーネントにおいて、ステム部と骨頭部との間に伝わる力を緩和することを課題とする。 The stem portion S and the bone head H are both formed of a hard material, and since these are directly contacted and fixed by fitting, almost all the force applied to the bone head H is transmitted to the stem portion S. Such a force applied to the stem portion S embedded in the femur F induces loosening of the adhesion and micromotion on the adhesion surface between the stem portion S and the femur F, and the stem portion S is worn or broken. It is thought that it is a cause, and it is contributed to a thigh pain and a femur fracture.
On the contrary, since the force applied to the stem S is transmitted to the bone head H without being attenuated, this also contributes to the loosening of the acetabular component relative to the patient after the hip replacement or the patient after the hip replacement. It is considered to be or become the cause of deformation and osteoarthritis of the acetabular cartilage against.
In view of such a viewpoint, an object of the present invention is to alleviate a force transmitted between a stem portion and a bone head in a femoral component of an artificial hip joint.

上記課題を解決するために、本発明は次のような構成を有する。
請求項１に記載の発明は、嵌入孔が設けられた球状体からなる骨頭部と、先端に前記嵌入孔に嵌め入れて固定する当該嵌入孔に嵌る大きさ及び形状を有する係合ネックが形成された、大腿骨に埋め込まれるステム部と、相対する前記嵌入孔内面と前記係合ネック外面との間の少なくとも一部に狭持される薄い、粘弾性体又は前記骨頭部及びステム部より弾性変形しやすい弾性体からなり、抗生物質が添加される緩衝部材とを有する人工股関節用大腿骨コンポーネントである。
請求項２に記載の発明は、前記人工股関節用大腿骨コンポーネントにおいて、前記緩衝部材は少なくとも前記係合ネックの側周面を一周するように設けられるものである。
請求項３に記載の発明は、前記人工股関節用大腿骨コンポーネントにおいて、前記緩衝部材は少なくとも前記嵌入孔の底面に設けられるものである。
請求項４に記載の発明は、前記人工股関節用大腿骨コンポーネントと、前記骨頭部を回動可能に保持するカップを有する臼蓋コンポーネントとからなる人工股関節である。 In order to solve the above problems, the present invention has the following configuration.
According to the first aspect of the present invention, there is formed a bone head made of a spherical body provided with an insertion hole, and an engagement neck having a size and a shape that fits into the insertion hole that is fitted into the insertion hole and fixed at the tip. A thin, viscoelastic body sandwiched between at least part of the stem portion embedded in the femur and the opposed inner surface of the insertion hole and the outer surface of the engagement neck, or more elastic than the bone head and stem portion Ri Do from deformable elastic member is a femoral component for a hip prosthesis having a cushioning member which antibiotics are added.
According to a second aspect of the present invention, in the femoral component for an artificial hip joint, the buffer member is provided so as to go around the side peripheral surface of the engagement neck at least.
According to a third aspect of the present invention, in the femoral component for an artificial hip joint, the buffer member is provided at least on the bottom surface of the insertion hole.
The invention according to claim 4 is an artificial hip joint comprising the femoral component for an artificial hip joint and a acetabular component having a cup for rotatably holding the bone head.

請求項１に記載の発明は、ステム部の係合ネックと、骨頭部の嵌入孔との相対する面の少なくとも一部に粘弾性体からなる緩衝部材が狭持されるので、この接触面においては、ステム部と骨頭部間の間に伝わる力は、粘弾性体又は弾性体からなる緩衝部材が弾性変形やクリープ変形をすることにより緩和される。これにより、ステム部と大腿骨との接着の緩みやマイクロモーションが抑制され、ステム部の磨耗・折損、大腿部痛、大腿骨骨折、大腿骨の変形、臼蓋コンポーネントの緩み、臼蓋軟骨の変形等を抑制することができる。また、緩衝部材に抗生物質を添加することで、人工股関節置換術又は人工骨頭置換術をセメントレスにて施術する場合でも、周囲の組織や組織液及び血液中への抗生物質の長時間に渡る徐放が行なわれ、術後の感染症の発生を抑制することができる。
請求項２に記載の発明は、緩衝部材を係合ネックの周面を一周するように設けることで、係合ネックの側方から加わる全方位の力を緩和することができる。
請求項３に記載の発明は、緩衝部材を嵌入孔の底面に設けることで、係合ネックの中心軸方向に加わる力を緩和することができる。
請求項４に記載の発明は、人工股関節において、上記のような効果を奏することができる。

According to the first aspect of the present invention, since the buffer member made of a viscoelastic body is sandwiched between at least a part of the opposing surfaces of the engagement neck of the stem portion and the insertion hole of the bone head, The force transmitted between the stem portion and the bone head is alleviated by the elastic deformation or the creep deformation of the buffer member made of the viscoelastic body or the elastic body. As a result, loosening and micromotion of the adhesion between the stem part and the femur are suppressed, wear and tear of the stem part, thigh pain, femoral fracture, femoral deformation, acetabular component loosening, acetabular cartilage Can be suppressed. In addition, by adding antibiotics to the cushioning member, even when artificial hip joint replacement or artificial head replacement is performed without cement, the antibiotics in the surrounding tissue, tissue fluid, and blood are gradually removed over a long period of time. The postoperative infection can be suppressed.
According to the second aspect of the present invention, by providing the buffer member so as to go around the peripheral surface of the engagement neck, the force in all directions applied from the side of the engagement neck can be reduced.
The invention according to claim 3 can relieve the force applied in the central axis direction of the engagement neck by providing the buffer member on the bottom surface of the insertion hole.
The invention according to claim 4 can achieve the above-described effects in an artificial hip joint.

Claims

A bone head made of a spherical body provided with a fitting hole;
A stem portion embedded in the femur, in which an engagement neck having a size and a shape that fits into the insertion hole that is fitted into and fixed to the insertion hole at a distal end is formed;
Opposite the insertion hole inner surface and thin are held at least partly between said engagement neck outer surface, Ri Do a viscoelastic body or the bone head and elastically deformable elastic body from the stem portion, antibiotics A femoral component for an artificial hip joint having a cushioning member added thereto .

The femoral component for a hip prosthesis according to claim 1, wherein the buffer member is provided so as to go around at least a side peripheral surface of the engagement neck.

The femoral component for an artificial hip joint according to claim 1, wherein the buffer member is provided at least on a bottom surface of the insertion hole.

An artificial hip joint comprising the femoral component for an artificial hip joint according to any one of claims 1 to 3 and a acetabular component having a cup that rotatably holds the bone head.