| 摘要 |
A device for lengthening bone in a human or animal by incrementally extending the distance between discrete separated portions of the bone to permit continued bone growth between the separated portions comprising an intramedullary nail having distal and proximal portions both of which are secured within the medullar canal of the bone. A hydraulic cylinder is connected to the proximal portion and a piston is connected to the distal portion of the nail. An implantable supply of operating fluid communicates with the cylinder and ratcheting mechanism, between the piston and cylinder, limit their relative movement. A shock absorber mechanism permits limited lost motion between the piston and cylinder and ratcheting release means are employed to permit the piston and cylinder to reverse directions. Various interchangeable distal tips are disclosed to accommodate not only different bones but differently shaped medullar canals. |
