To provide a circular type external fixator in which a risk of postoperative infection is reduced, and further pain is reduced by the towing of soft tissue using bone extension.SOLUTION: A circular type external fixator is characterized in that an error in the implantation direction is adjusted in a movable range of a half-size ball 32, the error in the vertical direction is adjusted in a length range of a screw part 31g, and the error in the lateral direction is adjusted in a length range of a long hole 11a so that multiple screw pins 12 can be fixed in an external fixator without difficulty while being pierced in a breakage bone, and thereby it is fastened with a fixing member 35, a spring-washer 45 and a right screw nut 46. Further, a bone extension device has a stretching adjustment unit 43a being rotated manually in order to equalize the stress received by the multiple screw pins 12 by the towing of the soft tissue, and then a right screw member 41 and a left screw member 42 are made to slide in the direction of upper and lower two rings 11, that is, in the opposite direction to be extended equally, and thereby the pain of the soft tissue can be reduced.SELECTED DRAWING: Figure 2【課題】術後感染の危険性が少なく、さらに骨延長による軟部組織の牽引で、痛みの少ないサーキュラー型創外固定器を提供する。【解決手段】複数のスクリュウピン１２は、破折骨に刺入されたままの状態で、無理なく創外固定器に固定することができるよう、刺入方向の誤差は半切ボール３２の可動範囲、上下方向の誤差はネジ部３１ｇの長さ範囲、左右方向の誤差は長穴１１ａの長さの範囲で調整して、固定部材３５、スプリングワッシャ４５、右ネジナット４６で締結する。さらに、軟部組織の牽引で、複数のスクリュウピン１２が受ける応力を均等にするため、骨延長器は伸縮調整部４３ａを手動で回転させると、右ネジ部材４１と左ネジ部材４２は、上下２つのリング１１の方向つまり、反対方向にスライドして均等に延長されることで、軟部組織の痛みを軽減できるサーキュラー型創外固定器を特徴とする。【選択図】図２
