Abstract: A bone expandable device comprises two expanding members, a retractable member and a fastener. The two expanding members are joined together for forming a cavity therebetween, each the expanding member includes two flexible parts and a fixed part. The two flexible parts are connected to the fixed part separately, and each the flexible part can be bent from the fixed part. The retractable member is disposed in the cavity and includes a first part and a second part. The first part is movably sleeved on the second part, and a length of the retractable member can be adjusted by moving the first part or the second part. The fastener is for fastening the two expanding members together. When the length of the retractable member is increasing, the two opposite ends of the retractable member would push against the four flexible parts to expand the flexible parts outwardly from the cavity.

Abstract: A bone expandable device comprises two expanding members, a retractable member and a fastener. The two expanding members are joined together for forming a cavity therebetween, each the expanding member includes two flexible parts and a fixed part. The two flexible parts are connected to the fixed part separately, and each the flexible part can be bent from the fixed part. The retractable member is disposed in the cavity and includes a first part and a second part. The first part is movably sleeved on the second part, and a length of the retractable member can be adjusted by moving the first part or the second part. The fastener is for fastening the two expanding members together. When the length of the retractable member is increasing, the two opposite ends of the retractable member would push against the four flexible parts to expand the flexible parts outwardly from the cavity.

Abstract: A vertebral body expanding device includes a bolt, a first nut, a second nut, a first supporting member, a second supporting member, a third supporting member, a fourth supporting member, a first expanding member and a second expanding member. The first nut and the second nut engage the bolt by two opposite screw threads. The first and third supporting members are pivoted to upper and lower ends of the first nut respectively, and the second and fourth supporting members are pivoted to upper end and lower ends of the second nut respectively. The first and second supporting members are pivoted to a lateral surface of the first expanding member, and the third and fourth supporting members are pivoted to a lateral surface of the second expanding member. The first and second nuts move toward or away from each other to retract or expand the first and second expanding members.