Progressive elongation centro-medullar nail
AssigneeMedinov SARL
InventorsPaul Grammont, Jean M. Guichet
Life of this patent
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Abstract
A device including a nail for gradually lengthening long bones including outer and inner sliding tubes connected by a double ratchet mechanism, the nail being fixed by its two extremities in the bone, and the device being entirely included in the concerned bone, being lengthened post-operatively by maneuvers applied on the limb. Rotation of a distal part of the limb with respect to proximal part of the limb allows rotation of the ratchet mechanism with lengthening of the device in one direction, and keeping of the gained length in the other direction while returning to the neutral axis of the rotation of the device, thereby featuring a dynamization system, and a system, to limit the range of rotation of the device.
Claims20
An intramedullary nail for use in a medullary cavity of a patient's bone, said nail comprising:
- an elongated hollow barrel;
- an elongated tube movably mounted within said barrel, one end of said tube being disposed within a hollow portion of said barrel and an other end of said tube being outside of said barrel;
- locking means positioned within the hollow portion of said barrel, said locking means having first and second opposed ends;
- means for securing said first end of said locking means against rotation within said barrel;
- and
- position-controlling means positioned within said barrel, said position-controlling means cooperating with the hollow portion of said barrel, said one end of said tube and said second end of said locking means, wherein rotation of said tube relative to said barrel in a first direction causes said position-controlling means to operate in a first manner to move said tube out of said barrel a predetermined amount, while said locking means prevents operation of said position-controlling means to maintain the relative longitudinal positions of said barrel and said tube when said tube rotates in a direction opposite to said first direction.
Dependencies are inferred from the claim text.